SubTitle22a-133k-1_22a-133k-3. Remediation Standards, Title22a Environmental Protection, Regulations of Connecticut State Agencies

Regulations of Connecticut State Agencies (Last Updated: June 14,2023)

Title22a Environmental Protection

SubTitle22a-133k-1_22a-133k-3. Remediation Standards

Sec. 22a-133k-1. General Provisions

Latest version.

(a) Definitions

For the purposes of the RSRs, the following terms have the following meanings:

(1) “Application of pesticides” means the spraying, spreading, injection, placement, or other use of pesticides at a parcel for the pesticide’s intended purpose, but does not include other releases of pesticides such as those from the handling, mixing, storing, spilling, leaking or disposing of pesticides, or releases of pesticides from equipment cleaning or repair.

(2) “Aquifer protection area” has the same meaning as provided in section 22a-354h of the Connecticut General Statutes.

(3) “Area of influence” has the same meaning as provided in section 22a-354b-1(a) of the Regulations of Connecticut State Agencies.

(4) “Areal extent of a groundwater plume” means the surface area beneath which groundwater is polluted by a release and in which one or more substances from such release or mobilized by such release is present at a concentration above the laboratory reporting limit.

(5) “Background concentration” means the concentration of a substance in soil or groundwater that, based on a validated conceptual site model, is:

(A) In the general geographic vicinity of a release; and

(B) Either:

(i) Naturally occurring; or

(ii) Minimally affected by human influences at concentrations equal to or less than criteria specified in the RSRs.

(6) “Carcinogenic substance” means a substance defined as a “carcinogen” by federal or state agencies and for which a quantitative health risk extrapolation is available.

(7) “CFR” means the Code of Federal Regulations.

(8) “Commissioner” means the Commissioner of Energy and Environmental Protection or the commissioner’s designee.

(9) “Conceptual site model” means a representation in three dimensions of environmental conditions at a release area that is developed through a multi-phased investigative approach which validates such representation with information about, including, but not limited to, a substance’s release, fate and transport, and pathway to human and environmental receptors.

(10) “Demarcation layer” means a brightly-colored, tear-resistant, environmentally-stable marker layer installed at an appropriate depth, suitable to indicate the presence of polluted soil beneath such layer.

(11) “Department” means the Department of Energy and Environmental Protection.

(12) “Dilution factor” means the ratio by which the concentration of a substance dissolving into soil water is reduced by dilution with groundwater or surface water, as applicable.

(13) “Dilution and attenuation factor” or “Dilution attenuation factor” means the ratio by which the concentration of a substance dissolving into soil water is reduced by dilution with groundwater and by sorption to unsaturated or saturated soil, or by degradation, transformation or stabilization of the substance.

(14) “Diminishing state groundwater plume” means a groundwater plume that has been characterized seasonally and in three dimensions, provided that the characterization of such plume:

(A) Is consistent with a validated conceptual site model; and

(B) Demonstrates that such plume:

(i) Is not migrating, or has very limited potential to migrate, in any direction; and

(ii) Is comprised only of substances whose concentrations have decreased and will continue to decrease over time, except for the concentrations of related breakdown components, provided it is demonstrated that concentrations of such breakdown components are not a known risk to human health and the environment. For purposes of this clause, “breakdown components” means constituent compounds that result from the alteration of an original compound in the environment.

(15) “Direct exposure criteria” or “DEC” means the criteria identified in Appendix A of the RSRs, alternative direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(d) of the RSRs, or direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(b)(7) of the RSRs.

(16) “Downgradient” means in the direction of the maximum rate of decrease of hydraulic head.

(17) “Downgradient area” with respect to a release of a substance means the area bounded by:

(A) The width of the release area of such substance perpendicular to the direction of groundwater flow;

(B) Two side boundary lines parallel to the downgradient direction of groundwater flow extending from the two endpoints of said width to the downgradient parcel boundary; and

(C) The downgradient parcel boundary extending between the two side boundary lines, excluding any portion of such downgradient area that is either affected by any other release of such substance or beneath an existing permanent structure.

(18) “Engineered control” means any physical barrier, system, technology or method that prevents exposure to polluted soil, or minimizes migration of liquids or vapor through such soil, and complies with the other requirements specified in section 22a-133k-2(f)(2) of the RSRs.

(19) “Environmental land use restriction” or “ELUR” has the same meaning as provided in section 22a-133q-1 of the Regulations of Connecticut State Agencies.

(20) “Environmentally isolated soil” means polluted soil which is above the seasonal high water table and is not subject to infiltration in accordance with section 22a-133k-2(c)(5)(A) of the RSRs, thereby preventing the leaching of pollutants from such soil into groundwater.

(21) “EPA” means the United States Environmental Protection Agency.

(22) “ETPH” means extractable total petroleum hydrocarbons.

(23) “Environmental use restriction” or “EUR” has the same meaning as provided in section 22a- 133q-1 of the Regulations of Connecticut State Agencies.

(24) “EUR regulations” has the same meaning as provided in section 22a-133q-1 of the Regulations of Connecticut State Agencies.

(25) “Excess lifetime cancer risk” means the estimated probability that an individual’s exposure to a substance could result in cancer.

(26) “GA area” means an area where the groundwater classification is GA, GAA, or GAAs.

(27) “GB area” means an area where the groundwater classification is GB.

(28) “Groundwater” means that portion of “waters” as defined in section 22a-423 of the Connecticut General Statutes at or below the water table.

(29) “Groundwater classification” means the groundwater classification established in the Water Quality Standards.

(30) “Groundwater criteria” means surface water protection criteria, water quality criteria, volatilization criteria, groundwater protection criteria, and background concentration, as applicable.

(31) “ Groundwater divide” means a line on the water table from which the water table slopes downward in both directions away from such line.

(32) “Groundwater plume” means groundwater that has been polluted by a release and is emanating from a release area and in which one or more substances from such release is present at a concentration above the laboratory reporting limit.

(33) “Groundwater protection criteria” or “GWPC” means the criteria identified in Appendix C of the RSRs, alternative groundwater protection criteria calculated by an LEP or approved by the commissioner pursuant to section 22a-133k-3(d)(2) of the RSRs, or groundwater protection criteria approved by the commissioner pursuant to section 22a-133k-3(i)(1) of the RSRs.

(34) “Hardscape” means man-made features that are incorporated into landscaped areas, including walkways constructed with asphalt, concrete, or pavers; gravel parking areas and driveways; paved or gravel storm water features; placement of natural rock; rip-rap; and non-vegetated retaining walls.

(35) “Hazard index” means the calculation of the potential for non-cancer health effects as a result of exposure to one or more substances with the same or similar modes of toxic action or toxic endpoints.

(36) “Hydraulic gradient” means the change in hydraulic head per unit distance.

(37) “Hydraulic head” means the elevation to which water rises in a piezometer or a well.

(38) “Immobilization” or “Immobilize” means the act of binding a substance to create a solid that is resistant to leaching and eliminates or virtually eliminates the mobility of a substance from such solid, including, but not limited to, solidification to physically bind or enclose a substance within a stabilized mass, stabilization through chemical reactions between a stabilizing agent and a substance, or encapsulation by coating a substance.

(39) “Inaccessible soil” means soil that meets at least one of the following conditions:

(A) Is more than four feet below the ground surface;

(B) Is more than two feet below a paved ground surface comprised of bituminous concrete that, at a minimum, is three inches thick or reinforced concrete that, at a minimum, is four inches thick;

(D) Is polluted fill:

(i) Beneath a paved ground surface comprised of bituminous concrete that, at a minimum, is three inches thick or reinforced concrete that, at a minimum, is four inches thick; and

(ii) That exceeds the applicable direct exposure criteria solely due to:

(I) Semi-volatile organic substances or petroleum hydrocarbons that are normal constituents of bituminous concrete; or

(II) Metals at concentrations that are equal to or less than two times the applicable direct exposure criteria.

(40) “Industrial/commercial activity” means any activity related to the commercial production, distribution, manufacture or sale of goods, services, or any other activity which is not a residential activity .

(41) “Industrial/commercial direct exposure criteria” means the criteria identified as industrial/commercial direct exposure criteria in Appendix A of the RSRs, alternative direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(d) of the RSRs, or direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(b)(7) of the RSRs.

(42) “Industrial/commercial volatilization criteria” means the criteria identified as industrial/commercial volatilization criteria in Appendix E and Appendix F of the RSRs, alternative volatilization criteria approved by the commissioner pursuant to section 22a- 133k-3(c)(4) of the RSRs, or volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(i)(3) of the RSRs.

(43) “Intermittent watercourse” is a type of watercourse, as the term is defined in section 22a-38 of the Connecticut General Statutes, delineated in accordance with section 22a-38 of the Connecticut General Statutes.

(44) “Laboratory reporting limit” means the lowest concentration at which an analyte can be detected in a sample of environmental media by a laboratory certified by the Department of Public Health pursuant to section 19a-29a of the Connecticut General Statutes and which concentration can be reported with a reasonable degree of accuracy and precision pursuant to section 22a-133k-1(h) of the RSRs.

(45) “Licensed environmental professional” or “LEP” means an environmental professional who has a current valid license issued by the commissioner pursuant to section 22a-133v of the Connecticut General Statutes.

(46) “Matrix interference” means either a positive or negative effect when measuring the concentration of a substance in a sample that creates erroneous results for an analyte.

(47) “Maximum extent practicable” means the greatest degree of remediation that can be achieved using sound engineering and hydrogeologic practices without taking cost into consideration.

(48) “Maximum extent prudent” means the greatest degree of remediation that can be achieved using sound engineering and hydrogeologic practices that the commissioner deems reasonable, taking into consideration cost in proportion to social and environmental benefits, provided that a mere showing of expense will not necessarily render an alternative unreasonable.

(49) “Monitored natural attenuation” means representative groundwater monitoring of the natural attenuation of each substance in a groundwater plume to a concentration equal to or less than groundwater criteria, provided such monitoring demonstrates that:

(A) Such attenuation is occurring, and will continue to occur, as evidenced by changes in chemical concentrations, alterations of chemical components, and hydrogeologic conditions within the aquifer after completing the remediation of a release area in a manner that will achieve compliance with the RSRs; and

(B) The only remaining groundwater plume from a release is a diminishing state groundwater plume.

(50) “Natural attenuation” means a decrease in concentration of a substance in groundwater through operation of natural physical or chemical processes, including, but not limited to, adsorption, absorption, dilution, phase transfer, oxidation, organic complexation, biodegradation, dispersion and diffusion.

(51) “Naturally occurring” means present in the environment in forms that have not been influenced by human activity.

(52) “Ninety-five (95) percent upper confidence level of the arithmetic mean” means a value that, when repeatedly calculated for randomly drawn subsets of size n from a population, equals or exceeds the population arithmetic mean ninety-five (95) percent of the time.

(53) “Non-aqueous phase liquid” or “NAPL” means a liquid that is not dissolved in water.

(54) “Notice of Activity and Use Limitation” or “NAUL” has the same meaning provided in section 22a-133q-1 of the Regulations of Connecticut State Agencies.

(55) “Organoleptic” means the capability to produce a detectable sensory stimulus such as odor or taste.

(56) “Parcel” means a piece, tract, or lot of land, together with the buildings and other improvements situated thereon, a legal description of which piece, tract, or lot is contained in a deed or other instrument of conveyance.

(57) “PCBs” means polychlorinated biphenyls.

(58) “PPB” means parts per billion.

(59) “PPM” means parts per million.

(60) “Person” has the same meaning as provided in section 22a-2(b) of the Connecticut General Statutes.

(61) “Pesticide” has the same meaning as provided in section 22a-47(w) of the Connecticut General Statutes.

(62) “Pollutant mobility criteria” or “PMC” means the criteria identified in Appendix B of the RSRs, alternative pollutant mobility criteria calculated by an LEP or approved by the commissioner pursuant to section 22a-133k-2(d) of the RSRs, or pollutant mobility criteria approved by the commissioner pursuant to section 22a-133k-2(c)(6) of the RSRs.

(63) “Polluted fill” means soil which contained polluting substances at the time such soil was deposited as fill material.

(64) “Polluted material” means soil that has been historically intermixed with coal ash, wood ash, coal fragments, coal slag, coal clinkers, asphalt paving fragments, or any combination thereof.

(65) “Polluted soil” means soil affected by a release of a substance at a concentration above the laboratory reporting limit for such substance.

(66) “Pollution” has the same meaning as provided in section 22a-423 of the Connecticut General Statutes.

(67) “Potential public water supply resource” means any “potential well fields” as defined in section 22a-354a of the Connecticut General Statutes, or any area mapped by the commissioner pursuant to section 22a-354c(b) of the Connecticut General Statutes.

(68) “Public roadway” means any portion of a federal, state, town, or other public highway, including, but not limited to, road, street, parkway, limited access highway, boulevard, or avenue paved with bituminous concrete or concrete, under the control of the federal government, the state or any political subdivision of the state, any quasi-governmental entity or municipal economic development agency or entity created or operating under the Connecticut General Statutes, that is dedicated, appropriated, or open to the movement of vehicles or pedestrians, including appurtenant sidewalks, medians, and shoulders, but excluding landscaped or grassy areas beyond the outer edge of the travel way.

(69) “Public water supply distribution system” means any combination of pipes, tanks, pumps, etc. which deliver water from the source or treatment facility to the consumer from any water company, as defined in section 25-32a of the Connecticut General Statutes, supplying water to two (2) or more consumers, or twenty-five (25) or more persons daily, at least sixty (60) days of the year.

(70) “Q99” means the daily stream flow that is predicted to be equaled or exceeded on ninety-nine (99) percent of days in a year, and is calculated using methods developed by the U.S. Geological Survey (StreamStats).

(71) “Release” means any discharge, spillage, uncontrolled loss, seepage, filtration, leakage, injection, escape, dumping, pumping, pouring, emitting, emptying, or disposal of a substance.

(72) “Release area” means the land area at and beneath which polluted soil is located as a result of a release.

(73) “Remediation” means the containment, removal, mitigation, or abatement of pollution, or a substance which poses a risk to human health or the environment, and includes, but is not limited to, the reduction of pollution by natural attenuation.

(74) “Reasonable confidence protocols” or “RCPs” means any reasonable confidence protocols, quality assurance requirements, or quality control requirements, posted by the commissioner on the department’s internet website, regarding the laboratory measurements of the concentration of a substance in a sample.

(75) “Remediation Standard Regulations” or “RSRs” means sections 22a-133k-1 to 22a-133k-3, inclusive, of the Regulations of Connecticut State Agencies, including Appendix A to Appendix I, inclusive, of said regulations and when identified by a specific reference, “RSRs” also means any individual section or specific provision of sections 22a-133k-1 to 22a-133k-3, inclusive, of the Regulations of Connecticut State Agencies, including Appendix A to Appendix I, of said regulations.

(76) “Residential activity” means any activity at:

(A) A place intended for people to live, including, but not limited to, a residence, dwelling, house, apartment, condominium, nursing home, or dormitory;

(B) A pre-school, primary school, secondary school, day care center, playground, or outdoor recreational area; or

(77) “Residential direct exposure criteria” means the criteria identified as residential direct exposure criteria in Appendix A of the RSRs, alternative direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(d) of the RSRs, or direct exposure criteria approved by the commissioner pursuant to section 22a-133k-2(b)(7) of the RSRs.

(78) “Residential volatilization criteria” means the criteria identified as residential volatilization criteria in Appendix E and Appendix F of the RSRs, alternative volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(c)(4) of the RSRs, or volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(i)(3) of the RSRs.

(79) “Seasonal high water table” means, on an annual basis, the highest plane in the ground at which all pore spaces are filled with water at atmospheric pressure.

(80) “Seasonal low water table” means, on an annual basis, the lowest plane in the ground at which all pore spaces are filled with water at atmospheric pressure.

(81) “Sediment” means unconsolidated material occurring in a watercourse, as that term is defined in section 22a-38 of the Connecticut General Statutes, and in estuarine water or marine water.

(82) “Semi-volatile organic substance” means an organic substance that has a higher molecular weight and higher boiling point than a volatile organic substance.

(83) “Soil” means unconsolidated geologic material overlying bedrock, including, but not limited to, sediment that has been removed from any surface water body and placed on dry land.

(84) “Soil water” means that portion of “waters” as defined in section 22a-423 of the Connecticut General Statutes, which is above the water table.

(85) “Soil vapor” means gaseous substances in the space between particles of soil.

(86) “SPLP” means Synthetic Precipitation Leaching Procedure EPA Method 1312 as set forth in “Test Methods for Evaluating Solid Waste: Physical/Chemical Methods”, SW-846, U.S. Environmental Protection Agency, Office of Solid Waste, Washington D.C. 20460.

(87) “Substance” means an element, compound or material which, when added to air, water, soil or sediment, may alter the physical, chemical, biological or other characteristic of such air, water, soil or sediment.

(88) “Subject area” means an area where the RSRs require an EUR to be placed and maintained as part of the selected remedial approach. “Subject area” includes the area subject to the restrictions and requirements of an EUR after such EUR has been recorded. There can be multiple subject areas on a parcel, or an entire parcel may comprise a single subject area.

(89) “Surface-water protection criteria” or “SWPC” means the criteria identified in Appendix D of the RSRs, alternative surface water protection criteria calculated by an LEP or approved by the commissioner pursuant to section 22a-133k-3(b) of the Regulations of Connecticut State Agencies, or surface water protection criteria approved by the commissioner pursuant to section 22a-133k-3(i)(2) of the RSRs.

(90) “TCLP” means Toxicity Characteristic Leaching Procedure EPA Method 1311 as set forth in “Test Methods for Evaluating Solid Waste: Physical/Chemical Methods”, SW-846, U.S. Environmental Protection Agency, Office of Solid Waste, Washington D.C. 20460.

(91) “Technically impracticable” means a determination by the commissioner that further reduction of the concentration of a substance in soil or groundwater cannot be achieved using sound engineering and hydrogeologic remediation practices.

(92) “TI Zone” means the areal extent of a substance that is technically impracticable to remediate to the applicable groundwater criteria.

(93) “Upgradient” means in the direction of maximum rate of increase of hydraulic head.

(94) “Upgradient area” with respect to a release area of a substance means the area bounded by:

(A) The width of the release area of such substance perpendicular to the direction of groundwater flow;

(B) Two side boundary lines parallel to the upgradient direction of groundwater flow extending from the two endpoints of said width to the upgradient parcel boundary; and

(C) The upgradient parcel boundary extending between the two side boundary lines, excluding any portion of such upgradient area that is affected by any other release of such substance, or beneath an existing permanent structure.

(95) “Volatilization criteria” means the criteria identified in Appendix E and Appendix F of the RSRs, alternative volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(c)(4) of the RSRs, or volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(i)(3) of the RSRs.

(96) “Volatilization criteria for groundwater” means the criteria identified in Appendix E of the RSRs, alternative volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(c)(4) of the RSRs, or volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(i)(3) of the RSRs.

(97) “Volatilization criteria for soil vapor” means the criteria identified in Appendix F of the RSRs, alternative volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(c)(4) of the RSRs, or volatilization criteria approved by the commissioner pursuant to section 22a-133k-3(i)(3) of the RSRs.

(98) “Volatile organic substance” means an organic substance that has a high vapor pressure and low boiling point at room temperature.

(99) “Volatile petroleum substance” means a volatile organic substance found in gasoline, diesel fuel, fuel oil, heating oil, kerosene, jet fuel, or similar fuels, along with volatile organic substances that may have been used as fuel additives.

(100) “Water table” means the plane in the ground at which all pore spaces are filled with water at atmospheric pressure.

(101) “Water quality criteria” means the lower of the human health or aquatic life criteria contained in Table 3 of the Water Quality Standards.

(102) “Water quality standards” means the Connecticut Water Quality Standards in sections 22a-426-1 to 22a-426-9, inclusive, of the Regulations of Connecticut State Agencies and the Classification Maps adopted pursuant to section 22a-426 of the Connecticut General Statues.

(103) “Wetland” has the same meaning as “wetlands” as provided in section 22a-38(15) of the Connecticut General Statutes or “wetland” as provided in section 22a-29(2) of the Connecticut General Statutes.

(b) Applicability

(1) General Applicability

(A) The RSRs apply to any action taken to remediate polluted soil, surface water or groundwater at or emanating from a release area which action is required pursuant to Chapter 445, Chapter 446k, or section 22a-208a(c)(2) of the Connecticut General Statutes, including, but not limited to, any such action required to be taken or verified by a licensed environmental professional.

(B) The RSRs do not apply to:

(i) Naturally occurring substances found in the environment in the absence of a release; or

(ii) Pollution within the zone of influence of a groundwater discharge permitted by the commissioner in accordance with section 22a-430 of the Connecticut General Statutes.

(2) Characterization

All investigation and remediation undertaken to comply with the RSRs shall be based on a representative characterization of a release, using a conceptual site model developed in accordance with prevailing standards and guidelines, such as the department’s “Site Characterization Guidance Document” as amended.

(3) Other Requirements

All remediation undertaken to satisfy the RSRs shall be conducted in accordance with all federal, state, and local requirements, including, but not limited to, 40 CFR Part 761, all permits, and other required authorizations. Nothing in this subsection shall be construed as requiring any further remediation of any release which has been remediated and which remediation has been approved in writing by the commissioner, unless the commissioner takes action to require such remediation pursuant to any section of Chapter 446k of the Connecticut General Statutes.

(4) Construction of Regulations

In the construction of the RSRs, terms or words in the singular may be construed and applied to more than one thing and terms or words in the plural may be construed and applied to the singular or just one thing.

The commissioner shall make best efforts within available resources to process in a timely manner any variance or alternative criteria request pursuant to the RSRs. The commissioner shall, upon request, provide estimated time frames for any such review. In establishing estimated time frames pursuant to this subsection, the commissioner shall take into account available resources, the complexity of the request, and the environmental and economic significance of the remediation.

(d) Public Participation

(1) Public Notice of Remediation

The public participation requirements of this subsection shall apply after a release has been investigated and a remedial action plan has been prepared but shall not apply to actions undertaken during an emergency or during other unplanned time-critical remedial actions.

(A) Providing Public Notice

The public notice prescribed in subparagraph (B) of this subdivision shall be provided through all of the following means:

(i) Submission of copies of such notice to the commissioner in accordance with subsection (g) of this section, and to the chief elected municipal official and the Director of Health of the municipality in which remediation will occur;

(ii) Publishing such notice in a newspaper having a general circulation in the municipality in which the remediation will occur; and

(iii) By either:

(I) Mailing a copy of such notice to each owner of record of each parcel that abuts the parcel to be remediated, at the address for such parcel on the last-completed grand list of the municipality in which the parcel is located; or

(II) Erecting and maintaining for at least thirty (30) days, a sign on the parcel to be remediated.

Such sign shall be not less than six (6) feet by four (4) feet, shall be clearly visible from the public roadway, and shall include the words “ENVIRONMENTAL CLEAN UP IN PROGRESS. FOR FURTHER INFORMATION CONTACT:” and include a telephone number and an electronic mail address from which any interested party may obtain additional information about the proposed remediation.

(B) Contents of Public Notice

Except for a sign erected in accordance with subparagraph (A)(iii)(II) of this subdivision, public notice of remediation required pursuant to subparagraph (A) of this subdivision shall include, at a minimum:

(i) The name and address of the owner of the parcel on which remediation will be undertaken and the person responsible for such remediation;

(ii) The address of the parcel or, if no address is available, a description of the location of the parcel relative to the nearest intersection of named streets;

(iii) The remediation identification number assigned by the department;

(iv) A brief description of the nature of the release and the substances being remediated;

(v) An electronic mail and postal mailing address, telephone number, and a point of contact to whom comments regarding the remediation can be submitted and from whom any interested person may obtain additional information about the proposed remediation;

(vi) A statement that public comments may be submitted, via electronic mail or in writing, for thirty (30) days after the date of publication of such notice; and

(vii) A brief description of the proposed remediation or a website where such information may be obtained. This description shall include, but need not be limited to:

(I) Use of any variance, engineered control, or EUR under the RSRs; and

(II) The approximate schedule to initiate and complete remediation, including any milestones or interim steps.

(2) Response to Public Comment

(A) There shall be a public comment period on the proposed remediation for thirty (30) days after publication of the newspaper notice required by subdivision (1)(A)(ii) of this subdivision.

(B) If no comments on the proposed remediation are received during the public comment period, the person responsible for remediation may commence with the proposed remediation.

(C) If comments on the proposed remediation are received during the public comment period, no later than thirty (30) days after close of the public comment period, the person responsible for remediation shall submit to the commissioner a written summary of all such comments and a proposed response to each such comment.

(D) Based on the summary of comments and proposed responses, the commissioner may:

(i) Direct the person responsible for remediation to send the written summary and response document to each person who submitted comments within thirty (30) days after the direction is given by the commissioner. If an electronic mail address is known, the summary and response document may be sent to a commenter using electronic mail;

(ii) Revise the written summary and response document and direct the person responsible for remediation to send the written summary and response document, as revised by the commissioner, to each person who submitted comments within thirty (30) days after the direction is given by the commissioner. If an electronic mail address is known, the summary and response document as revised by the commissioner may be sent to a commenter using electronic mail;

(iii) Determine that there is substantial public interest in the proposed remediation and direct the person responsible for the remediation to hold a public meeting regarding the proposed remediation. Notice of any such meeting shall be published in a newspaper of substantial circulation in the area of the proposed remediation at least thirty (30) days prior to such meeting. At such meeting all interested persons shall have reasonable opportunity to submit data, views, or arguments orally or in writing. Any such meeting shall not be conducted as, nor be considered to be, a contested case as that term is defined in section 4-166 of the Connecticut General Statutes. After the public meeting, the person responsible for remediation shall comply with subparagraph (C) of this subdivision and, except for this clause, the commissioner may then take actions specified under this subparagraph; or

(iv) Determine that the proposed remediation is premature, inadequate or deficient and indicate additional measures to be taken, including, but not limited to, additional investigation or different remediation.

(E) Within thirty (30) days after a public meeting held in accordance with subparagraph (D)(iii) of this subdivision, the person responsible for remediation shall provide to the commissioner a written summary of and response to any comments received during the public meeting and the commissioner may then take any of the actions in subclauses (i), (ii), or (iv) of subparagraph (D) of this subdivision.

(3) Requirements for Additional Public Notice

(A) If after commencing remediation there is a substantial change to the remedial actions for which notice of remediation has already been provided, the requirements of subdivision (1) and (2) of this subsection shall apply to and be complied with prior to undertaking any such change. For purposes of this subparagraph, a substantial change shall include, but not be limited to, use of any variance for environmentally isolated soil, inaccessible soil, engineered controls, or technical impracticability, for which public notice was not previously provided.

(B) After providing public notice of remediation in accordance with this subsection, if the remediation for which public notice was provided is not substantially initiated within three years of publication of such notice, notwithstanding the previous compliance with this subsection, the requirements of subdivision (1) and (2) of this subsection shall be undertaken again before remediation can commence.

(4) For the purposes of this subsection, “the person responsible for remediation” means the person legally required to investigate and remediate a parcel, or for voluntary remediation, the owner or person undertaking the investigation and remediation.

(e) Environmental Use Restrictions

(1) Whenever an EUR is required under the RSRs:

(A) An ELUR may always be used; and

(B) A NAUL may only be used:

(i) Pursuant to section 22a-133k-2(b)(2) of the RSRs, provided the subject area is zoned for industrial/commercial use and no holder of an interest in such area, other than the owner of such area, has a right of residential activity or use;

(ii) Pursuant to section 22a-133k-2(b)(3)(B) of the RSRs, provided the concentrations of substances in such inaccessible soil do not exceed ten (10) times the applicable direct exposure criteria;

(iii) Pursuant to section 22a-133k-2(b)(6) of the RSRs;

(iv) Pursuant to section 22a-133k-2(c)(5)(A) of the RSRs, provided that:

(I) The concentrations of substances in such soil do not exceed ten (10) times the applicable pollutant mobility criteria; or

(II) The total volume of soil that is environmentally isolated that exceeds ten (10) times the applicable pollutant mobility criteria is equal to or less than ten (10) cubic yards;

(v) Pursuant to section 22a-133k-2(d)(2)(A) of the RSRs;

(vi) Pursuant to section 22a-133k-2(f)(1) of the RSRs;

(vii) Pursuant to section 22a-133k-2(f)(2)(B) or section 22a-133k-2(f)(2)(C) of the RSRs, provided that the concentrations of the substances in polluted soil at the subject area are equal to or less than ten (10) times the applicable direct exposure criteria;

(viii) Pursuant to section 22a-133k-3(c)(1) or section 22a-133k-3(c)(2)(A) of the RSRs, provided the subject area is zoned for industrial/commercial use and no holder of an interest in such area, other than the owner of such area, has a right of residential activity or use;

(ix) Pursuant to section 22a-133k-3(c)(2)(B) of the RSRs;

(x) Pursuant to sections 22a-133k-3(c)(3), 22a-133k-3(c)(4), and 22a-133k-3(c)(5) of the RSRs; or

(xi) When an ELUR is required and the parcel on which it is to be recorded is owned by the state of Connecticut or the state of Connecticut purchases a property subject to an existing ELUR, the NAUL shall be approved by the commissioner.

(2) Each EUR under the RSRs shall be subject to and comply with all applicable requirements in section 22a-133o of the Connecticut General Statutes, the EUR Regulations and the RSRs.

(3) If the RSRs require an EUR:

(A) Such EUR shall be in effect prior to:

(i) An LEP’s verification, including an LEP’s interim verification, as those terms are defined in sections 22a-134 (19) and (28) of the Connecticut General Statutes; or

(ii) When required by the commissioner, the review and approval of the remediation by the commissioner; or

(B) When voluntary remediation is conducted pursuant to section 22a-133y of the Connecticut General Statutes, the documents required to be prepared by sections 22a-133q-2(b) or 22a-133q-3(b) of the EUR regulations, as applicable, shall be submitted as part of the final remedial action report at the time such report is submitted to the commissioner. Upon approval of such report by the commissioner, the EUR shall be executed within thirty-six (36) days of such approval and be put into effect in accordance with the EUR regulations.

(4) An EUR shall only be deemed to be in effect when such EUR is recorded on the land records in compliance with the EUR regulations.

(5) When a remedy is selected under the RSRs for which an EUR is required to be in effect for different subject areas on a parcel, a request shall be submitted to the commissioner to extend any deadline specified in the RSRs to prepare the materials required to obtain and request such EUR. The commissioner may approve or deny in writing such extension request. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that significant progress has been made to complete the remediation of the parcel and strict adherence to the stated deadline would create an extraordinary hardship.

(f) Financial Assurance

(1) A financial assurance shall be required to support an engineered control variance or a technical impracticability variance. Such assurance shall be:

(A) Established and maintained for the duration of the period that the engineered control or technical impracticability variance will be used to achieve compliance with the RSRs;

(B) Directly available to the commissioner to cover the costs of complying with the variance, including, but not limited to, operation, maintenance, inspection, monitoring, reporting, and other reasonably anticipated repairs and contingencies, in the event that the commissioner determines that such measures have not been performed as required by the RSRs; and

(C) Established in an amount equal to the cost of twenty (20) percent of thirty (30) years of operation, maintenance, inspection, monitoring, reporting, and other reasonably anticipated repairs and contingencies, which amount shall be maintained in effect for as long as the variance is used to achieve compliance with the RSRs, except this amount may be adjusted in accordance with subdivision (4) of this subsection.

(2) One or more of the following instruments, and no others, shall be used to satisfy the financial assurance requirements of this subsection:

(A) Trust Agreement or Trust Fund;

(B) Irrevocable Standby Letter of Credit;

(D) Certificate of Insurance.

(3) The wording of any instrument used to satisfy the requirements of this subsection shall be identical to the language prescribed by the commissioner, which language shall be posted on the department’s internet website. In addition, only an entity that satisfies the following requirements, as applicable, may issue an instrument used to satisfy the requirements of this subsection:

(A) Any trustee shall be an entity with authorization to act as a trustee and whose trust operations are regulated and examined by a federal or state agency;

(B) Any surety issuing a bond shall be among those listed as acceptable sureties on federal bonds in Circular 570 of the U.S. Department of Treasury;

(C) Any institution issuing a letter of credit shall be an entity that has the authority to issue letters of credit and whose letter of credit operations are regulated and examined by a federal or state agency; and

(D) Any insurer shall be licensed to transact the business of insurance, or eligible to provide insurance as an excess or surplus lines insurer, in one or more states.

(4) The amount of the financial assurance established pursuant to this subsection:

(A) Shall be adjusted for inflation at each five (5) year interval from the anniversary date of the establishment of the financial instrument. The adjustment shall be made by using an inflation factor derived from the most recent Implicit Price Deflator for Gross National Product published by the U.S. Department of Commerce in its “Survey of Current Business” and by multiplying the latest adjusted surety estimate for the site by that five-year inflation factor; and

(B) May be adjusted, subject to the discretion and written approval of the commissioner, to reflect any recalculation of the costs of operation, maintenance, inspection, monitoring, reporting, and other reasonably anticipated repairs and contingencies, in current dollars. Any request for an adjustment pursuant to this subparagraph shall be submitted to the commissioner in accordance with subsection (g) of this section.

(5) The requirements of this subsection shall not apply when:

(A) The entity responsible for remediation is a municipality, an agency or a political or administrative subdivision of the state or federal government; or

(B) The amount established under subparagraph (C) of subdivision (1) of this subsection is less than $10,000, unless the commissioner requires compliance with this subsection as a condition of approving the engineered control or technical impracticability variance.

(g) Use of Form Prescribed by the Commissioner

(1) Any submittal to the commissioner under the RSRs, including, but not limited to, a request for a variance, approval, notice, financial assurance, or EUR shall be submitted in writing on a form prescribed by the commissioner. Such form may require the following information:

(A) A description of the subject release;

(B) A description of the distribution and concentration of substances in soil and groundwater resulting from the subject release;

(D) A map showing the extent of all release areas on a parcel and the subject release area, including all sample locations;

(E) A map showing the extent of the subject groundwater plume and the concentration of substances in such plume;

(F) The tabulated analytical results of all laboratory analyses of soil and groundwater at the subject release area;

(G) A detailed justification for any variance or approval requested;

(H) Any information specifically required by the RSRs;

(I) A signed certification by the person submitting the form and, if provided on the form, certification by an LEP; and

(J) Any other information deemed necessary by the commissioner.

(2) If an electronic system is available for any submission identified in subdivision (1) of this subsection, such submittal shall be made pursuant to the instructions prescribed by the commissioner for the use of such electronic system.

(h) General Requirements for Analytical Data

(1) Analytical Data Quality and Usability

(A) With respect to analytical data, the following shall apply:

(i) All analytical data used to comply with the RSRs shall be scientifically valid and defensible, with a level of precision, accuracy, and sensitivity commensurate with its intended use. All analytical data submitted shall include an analytical data quality assessment and data usability evaluation prepared by individuals qualified to make such assessment or evaluation; and

(ii) If the commissioner determines that analytical data is not scientifically valid and defensible, or not of a sufficient level of precision, accuracy, and sensitivity to support the intended use of the data, the commissioner shall identify in writing the reasons for such conclusions and such data shall not be relied upon to demonstrate compliance with the RSRs.

(B) The commissioner may specify, by posting on the department’s internet website, methods or protocols to ensure that analytical data is of known and documented quality, including, but not limited to:

(i) RCPs for laboratory quality assurance and quality control measures or analytical methods for the evaluation of soil, sediment, groundwater, air, or soil vapor;

(ii) RCPs to be followed when establishing laboratory reporting limits; and

(iii) Methods and protocols for assessing data quality and evaluating data usability which can be used to determine whether data is scientifically valid and defensible, with a level of precision, accuracy, and sensitivity commensurate with its intended use.

(C) If an analytical data quality assessment or usability evaluation is conducted using a method or protocol other than the methods and protocols prescribed by the commissioner pursuant to this subdivision, such methods and protocols shall be documented and submitted for the commissioner’s review and evaluation. If the commissioner determines that such method or protocol is not scientifically valid and defensible, or not of a sufficient level of precision, accuracy, and sensitivity to support the intended use of the data, the commissioner shall identify in writing the reasons for such conclusions and such data shall not be relied upon to demonstrate compliance with the RSRs.

(2) Laboratory Reporting Limit Requirements

The laboratory reporting limit for the analysis of all samples used to comply with the RSRs shall:

(A) Be established at a concentration which is less than the applicable criteria, unless matrix interference or instrument limitations cannot be overcome by taking the additional actions listed in subdivisions (3) and (4) of this subsection;

(B) Not be artificially raised or lowered; and

(C) (i) Be equivalent to the concentration of the lowest standard used to calibrate the instrument actually analyzing a sample, provided such instrument has been calibrated in accordance with a method specified in an RCP or otherwise approved by the commissioner after consultation with the Commissioner of Public Health; or

(ii) Be equivalent to the concentration of a low-level reporting standard, as specified in an RCP or otherwise approved by the commissioner after consultation with the Commissioner of Public Health.

(3) Matrix Interference

(A) When analyzing a sample, if due to matrix interference the laboratory reporting limit for a substance is greater than the applicable RSR criteria for such substance, additional procedures, including, but not limited to, sample preparation procedures or alternative analytical methods shall be evaluated to determine whether the use of such procedures or methods will enable a laboratory reporting limit equal to or less than the applicable RSR criteria for such substance to be consistently and accurately achieved.

(B) In the circumstances described in subparagraph (A) of this subdivision, at a minimum, the following procedures or methods shall be evaluated in determining whether a laboratory reporting limit less than or equal to the applicable RSR criteria can be achieved:

(i) “Test Methods for Evaluating Solid Waste: Physical/Chemical Methods.” SW-846, U.S. Environmental Protection Agency, Office of Solid Waste, Washington D.C. 20460; or

(ii) Other analytical methods or procedures either approved in writing by EPA or, after consultation with the Commissioner of Public Health, approved in writing by the commissioner.

(C) (i) If pursuant to subparagraph (B) of this subdivision, a procedure or method is identified that will consistently and accurately achieve a laboratory reporting limit equal to or less than the applicable RSR criteria, the sample shall be re-analyzed for the subject substance using such procedure or method.

(ii) If after re-analysis the matrix interference is overcome and the lowest laboratory reporting limit for a substance that can be consistently and accurately achieved is now equal to or less than the applicable RSR criteria, the analytical results from such re-analysis can be used for the purpose of determining compliance with the RSRs.

(D) (i) If despite taking the actions to overcome matrix interference specified in subparagraphs (B) and (C) of this subdivision, a laboratory reporting limit less than or equal to the applicable RSR criteria cannot be consistently and accurately achieved, a report detailing the measures taken to overcome such matrix interference shall be submitted in writing to the commissioner. This report shall include, at a minimum, a description of the measures taken under subparagraphs (B) and (C) of this subdivision as well as the lowest achievable laboratory reporting limit consistently and accurately achievable under subparagraph (C)(i) of this subdivision.

(ii) The commissioner shall use the report submitted pursuant to clause (i) of this subparagraph to determine the lowest laboratory reporting limit for such substance that can be consistently and accurately achieved. If the commissioner determines that such laboratory reporting limit is still greater than the applicable RSR criteria, the commissioner may determine that compliance with the RSRs will be achieved when such laboratory substance has been remediated to such reporting limit. Any such determination by the commissioner shall be in writing and shall include the reasons for such determination.

(4) Instrument Limitations

(A) When analyzing a sample, if due to instrument limitations the laboratory reporting limit for a substance is greater than the applicable RSR criteria for such substance, alternative analytical methods or alternative instrumentation shall be evaluated to determine whether the use of such procedures or methods will enable a laboratory reporting limit equal to or less than the applicable RSR criteria for such substance to be consistently and accurately achieved.

(i) “Test Methods for Evaluating Solid Waste: Physical/Chemical Methods.” SW-846, U.S. Environmental Protection Agency, Office of Solid Waste, Washington D.C. 20460; or

(ii) Other analytical methods or instruments either approved in writing by EPA or, after consultation with the Commissioner of Public Health, approved in writing by the commissioner.

(C) (i) If pursuant to subparagraph (B) of this subdivision, a method or instrument is identified that will consistently and accurately achieve a laboratory reporting limit equal to or less than the applicable RSR criteria, the sample shall be re-analyzed for the subject substance using such method or instrument.

(ii) If after re-analysis the instrument limitation is overcome and the lowest laboratory reporting limit for a substance that can be consistently and accurately achieved is now equal to or less than the applicable RSR criteria, the analytical results from such re-analysis can be used for the purpose of determining compliance with the RSRs.

(D) (i) If despite taking the actions to overcome instrument limitations specified in subparagraphs (B) and (C) of this subdivision, a laboratory reporting limit less than or equal to the applicable RSR criteria cannot be consistently and accurately achieved, a report detailing the measures taken to overcome such instrument limitations shall be submitted in writing to the commissioner. This report shall include, at a minimum, a description of the measures taken under subparagraphs (B) and (C) of this subdivision as well as the lowest achievable laboratory reporting limit consistently and accurately achievable under subparagraph (C)(i) of this subdivision.

(ii) The commissioner shall use the report submitted pursuant to clause (i) of this subparagraph to determine the lowest laboratory reporting limit for such substance that can be consistently and accurately achieved. If the commissioner determines that such laboratory reporting limit is still greater than the applicable RSR criteria, the commissioner may determine that compliance with the RSRs will be achieved when such substance has been remediated to such laboratory reporting limit. Any such determination by the commissioner shall be in writing and shall include the reasons for such determination.

(i) Applicability of Remediation to Volatilization Criteria

(1) Provided the requirements of subdivision (2) of this subsection are satisfied, notwithstanding sections 22a-133k-3(a) and 22a-133-3(c) of the RSRs, volatile organic substances in groundwater may be remediated to:

(A) No more than fifteen (15) feet from the ground surface and no more than fifteen (15) feet from the lowest portion of a building under which groundwater is polluted with such substances; and

(B) The applicable groundwater volatilization criteria listed in the following table.

Volatile Substance	Residential Volatilization Criteria for Groundwater in µg/L (ppb)	Industrial/Commercial Volatilization Criteria for Groundwater in µg/L (ppb)
Acetone	50,000	50,000
Benzene	215	530
Bromoform	920	3,800
2-Butanone (MEK)	50,000	50,000
Carbon Tetrachloride	16	40
Chlorobenzene	1,800	6,150
Chloroform	287	710
1,2-Dichlorobenzene	30,500	50,000
1,3-Dichlorobenzene	24,200	50,000
1,4-Dichlorobenzene	50,000	50,000
1,1-Dichloroethane	34,600	50,000
1,2-Dichloroethane	21	90
1,1-Dichloroethylene	1	6
1,2-Dichloropropane	14	60
1,3-Dichloropropene	6	25
Ethyl benzene	50,000	50,000
Ethylene dibromide (EDB)	4	16
Methyl-tert-butyl-ether	50,000	50,000
Methyl isobutyl ketone	50,000	50,000
Methylene chloride	50,000	50,000
Styrene	580	2,065
1,1,1,2-Tetrachloroethane	12	50
1,1,2,2-Tetrachloroethane	23	100
Tetrachloroethylene	1,500	3,820
Toluene	23,500	50,000
1,1,1-Trichloroethane	20,400	50,000
1,1,2-Trichloroethane	8,000	19,600
Trichloroethylene	219	540
Vinyl chloride	2	2
Xylenes	21,300	50,000

(2) Compliance with subparagraphs (A) to (D) of this subdivision is required in order to be eligible to use the remediation standards set forth in subdivision (1) of this subsection.

(A) Prior to February 16, 2021:

(i) Remediation of such volatile organic substances shall have already been initiated or an LEP shall have documented in a Remedial Action Plan submitted to the commissioner such LEP’s determination that no remediation of such substances is required; and

(ii) If required, public notice of such remediation shall have been published, pursuant to subsection (d) of this section or any provision of the Connecticut General Statutes;

(B) On or before February 16, 2023, remediation of such volatile organic substances shall have been completed and approved by the commissioner, or completed sufficient to support an LEP’s verification, as that term is defined in section 22a-133v-1(dd) of the Regulations of Connecticut State Agencies;

(C) Compliance with all other requirements in the RSRs regarding volatile organic substances in groundwater shall have been achieved; and

(D) Documentation demonstrating compliance with this subsection is submitted to the commissioner by the earliest of the following dates:

(i) The applicable deadline set forth in section 22a-134a(g)(1)(B) or section 22a- 134a(g)(1)(C) of the Connecticut General Statutes;

(ii) The deadline set forth in any order issued by the commissioner;

(iii) The deadline set forth in any judgment issued by a court; or

(iv) February 16, 2026.

(3) In the event the requirements of subdivision (2) of this subsection are not complied with, volatile organic substances in groundwater shall be remediated to the standards set forth in section 22a-133k-3 of the RSRs, and not those in subdivision (1) of this subsection.

(Effective January 30, 1996; Amended June 27, 2013; Amended February 16, 2021)

Sec. 22a-133k-2. Remediation Standards for Soil

Latest version.

(a) Soil Criteria

Unless otherwise specified in the RSRs, polluted soil at a release area shall be remediated so that the concentration of a substance in such soil is equal to or less than:

(1) The direct exposure criteria and the pollutant mobility criteria; or

(2) The background concentration for soil.

(b) Direct Exposure Criteria

(1) Residential Direct Exposure Criteria

Except as otherwise specified in the RSRs, polluted soil at a release area shall be remediated so that the concentrations of substances in such soil are equal to or less than the residential direct exposure criteria.

(2) Use of Industrial/Commercial Direct Exposure Criteria

(A) Except for soil polluted with PCBs, polluted soil at a release area may be remediated so that the concentrations of substances in such soil are equal to or less than the industrial/commercial direct exposure criteria provided that:

(i) The subject area is not currently used for any residential activity;

(ii) Access to the parcel containing such release area is limited to individuals working at or temporarily visiting the subject parcel for industrial/commercial activity; and

(iii) An EUR is in effect for the subject area, which restriction shall:

(I) Prohibit residential activity; and

(II) Require compliance with clause (ii) of this subparagraph.

(B) Soil polluted with PCBs at a release area may be remediated so that the concentration of PCBs in such soil is equal to or less than the industrial/commercial direct exposure criteria for PCBs, provided that:

(i) The subject area is not currently used for any residential activity;

(ii) The parcel on which PCBs are present is used in accordance with title 40 CFR Part 761, including, but not limited to, those provisions of 40 CFR Part 761 regarding the requirement for high-occupancy areas;

(iii) The parcel upon which such release area is located is an outdoor electrical substation as defined in 40 CFR 761.123, or an other restricted access non-substation location, as defined in 40 CFR 761.123; and

(iv) An ELUR is in effect for the subject area, which restriction shall:

(I) Prohibit residential activity; and

(II) Require compliance with clauses (ii) and (iii) of this subparagraph.

(3) Conditional Exemptions for Inaccessible Soil

The provisions of this subdivision do not apply to soil polluted with PCBs.

(A) Soil at a release area that is fifteen feet or more below the ground surface is not required to be remediated to the direct exposure criteria.

(B) Inaccessible soil at a release area is not required to be remediated to the direct exposure criteria, provided that an EUR is in effect for the subject area, which restriction shall:

(i) Prohibit exposure to inaccessible soil, including, but not limited to, as a result of excavation, demolition, other intrusive activities, or natural occurrences;

(ii) Require that if soil is used to render polluted soil inaccessible, such soil is maintained and immediately replaced, as needed, to maintain the four (4) feet of soil cover and topography of the ground surface; and

(iii) Require, as applicable, that:

(I) Bituminous or reinforced concrete that renders the soil inaccessible is maintained in good condition, and free of gaps or cracks that could expose such soil;

(II) A building that is used to render soil inaccessible shall consist of a roof, exterior walls, and a concrete floor, maintained in good condition and free of gaps or cracks that could expose such soil and such building shall not be removed; or

(III) Provided that written notice is submitted to the commissioner, a permanent structure that renders the soil inaccessible, shall be maintained in good condition to the extent required to prevent exposure of such soil and shall not be removed.

(4) Conditional Exemption for Inaccessible Soil Polluted with PCBs

(A) Unless alternative criteria have been approved in accordance with subsection (d)(2) of this section, inaccessible soil polluted with PCBs may be remediated to the concentrations specified in subparagraph (B) of this subdivision, provided that an ELUR is in effect for the subject area, which restriction shall:

(i) Prohibit exposure to such inaccessible soil, including, but not limited to, as a result of excavation, demolition, other intrusive activities, or natural occurrences;

(ii) Prohibit residential activity;

(iii) Require that if soil is used to render polluted soil inaccessible, that such soil used to render polluted soil inaccessible is maintained and immediately replaced, as needed, to maintain the elevation and topography of the ground surface; and

(iv) Require, as applicable, that:

(I) Bituminous or reinforced concrete that renders the soil inaccessible is maintained in good condition and free of gaps or cracks that could expose such soil;

(III) Provided that written notice is submitted to the commissioner, a permanent structure approved in writing by the commissioner that renders the soil inaccessible shall be maintained in good condition to the extent required to prevent exposure of such soil and shall not be removed.

(B) Provided the requirements of subparagraph (A) of this subdivision are met, inaccessible soil at a release area polluted with PCBs may be remediated so that the concentrations of PCBs in such soil are equal to or less than:

(i) Ten (10) ppm PCBs by dry weight; and

(ii) Twenty-five (25) ppm PCBs by dry weight if such inaccessible soil is located on an “other restricted access (nonsubstation) location” or an “outdoor electrical substation” as those terms are defined in 40 CFR 761.123, provided that PCBs may be remediated to fifty (50) ppm by dry weight at an outdoor electric substation if a label or notice is visibly placed in the area in accordance with 40 CFR 761.125(c)(2).

(5) Conditional Exemption for Incidental Sources

Soil at a release area polluted with metals, petroleum hydrocarbons, or semi-volatile organic substances is not required to be remediated to the direct exposure criteria for those substances, provided such pollution is the result of:

(A) An incidental release due to the normal operation of motor vehicles, not including refueling, repair or maintenance of a motor vehicle; or

(B) Normal paving and maintenance of a consolidated bituminous concrete surface, provided such bituminous concrete surface has been maintained for its intended purpose.

(6) Conditional Exemption for Soil Polluted with Pesticides

Soil polluted with pesticides at a release area as a result of the application of pesticides is not required to be remediated to the direct exposure criteria for such pesticides, provided that a determination has been made that such pesticides are present solely as a result of the application of pesticides and:

(A) If the release area is used for residential activity:

(i) Protective measures are developed, implemented, and maintained to prevent human exposure to soil polluted with pesticides that exceeds residential direct exposure criteria. At a minimum, such measures shall consist of:

(I) Blending existing soil so that the concentration of substances for such pesticides in the top one (1) foot of soil are equal to or less than the direct exposure criteria, except for the area around existing mature trees;

(II) Covering soil with pavement, hardscape, buildings, or permanent structures; or

(III) Growing dense or vexatious vegetation on steep slopes to minimize the potential for direct exposure and erosion; and

(ii) An EUR is in effect for the subject area, which restriction shall:

(I) Identify the nature and extent of soil polluted with pesticides above residential direct exposure criteria and serve as notice of such polluted soil; and

(II) Require compliance with clause (i) of this subparagraph.

(B) If the release area is used for industrial/commercial activity:

(i) A soil management plan shall be developed, implemented, and maintained which plan shall include protective measures and ensure, at a minimum that any soil that exceeds the industrial/commercial direct exposure criteria is not exposed, including, but not limited to, as a result of excavation, demolition, or other activities and that any such soil is managed, restored, or disposed in a manner that is protective of human health and the environment and prevents human exposure to such soil, except that such soil management plan need not apply to any portion of a release area that is currently used for raising crops where pesticides are used; and

(ii) An EUR is in effect for the subject area, which restriction shall:

(I) Prohibit residential activity; and

(II) Require compliance with clause (i) of this subparagraph.

(7) Direct Exposure Criteria for Additional Polluting Substances

(A) Substances at a particular release area, for which direct exposure criteria are not specified in Appendix A of the RSRs shall be remediated to background concentration or to criteria obtained pursuant to this subdivision. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A proposed risk-based direct exposure criterion calculated in accordance with Appendix G of the RSRs, for each substance in such request;

(ii) The laboratory reporting limit for each substance; and

(iii) Any information about the health effects each substance may cause due to exposure pathways not accounted for in the risk-based direct exposure criterion proposed under clause (i) of this subparagraph.

(B) The commissioner may approve or deny in writing a request made under subparagraph (A) of this subdivision. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the requirements of this subdivision have been satisfied and that the proposed direct exposure criteria will be protective of human health and the environment.

(C) Unless prohibited in writing by the commissioner, criteria approved by the commissioner pursuant to subparagraph (A) of this subdivision, may be the subject of a request for alternative criteria under subsection (d)(2)(A) of this subsection.

(1) Pollutant Mobility Criteria

(A) Except as otherwise specified in the RSRs, polluted soil at a release area located in a GA area shall be remediated to the seasonal low water table; whereas polluted soil at a release area located in a GB area shall be remediated to the seasonal high water table. All such polluted soil shall be remediated so that the concentrations of substances in such soil are equal to or less than the applicable pollutant mobility criteria, as determined using:

(i) Analytical results reported on a per mass basis in mg/kg analysis for such substances, other than inorganic substances and PCBs; and

(ii) TCLP or SPLP analysis expressed in mg/L, or mass analysis in mg/kg divided by twenty, for inorganic substances and PCBs.

(B) In GA areas, if it is determined that remediation to the seasonal low water table is technically impracticable or would not result in the permanent elimination of a source of pollution, this subsection shall apply to polluted soil above the seasonal high water table.

(2) Optional Criteria for Polluted Soil in a GA Area

(A) Polluted Soil in any GA Area

Substances in polluted soil in a GA area may be remediated to a concentration equal to or less than the groundwater protection criteria for such substance based upon the analytical laboratory results of a TCLP or SPLP analysis.

(B) Polluted Soil, Except for PCBs or ETPH, in Certain GA Areas

(i) Substances, except for either PCBs or ETPH, in polluted soil in a GA area, may be remediated to a concentration at which the analytical laboratory results of:

(I) TCLP or SPLP analysis for such substance in soil is equal to or less than ten (10) times the groundwater protection criteria;

(II) TCLP or SPLP analysis for such substance in soil is equal to or less than the groundwater protection criteria multiplied by an alternative dilution or dilution and attenuation factor, approved in writing by the commissioner in accordance with subsection (d)(3)(B) of this section;

(III) Mass analysis for such substance in soil, is equal to or less than ten (10) times the applicable pollutant mobility criteria in Appendix B of the RSRs or approved in writing by the commissioner in accordance with subsection (c)(6) of this section; or

(IV) Mass analysis for such substance in soil is equal to or less than the applicable pollutant mobility criteria multiplied by an alternative dilution or dilution and attenuation factor approved in writing by the commissioner in accordance with subsection (d)(3)(B) of this section.

(ii) The remediation standards specified in clause (i) of this subparagraph may be used only if conditions at a release area satisfy the requirements of subparagraphs (C) and (D) of this subdivision and the notice requirements of subparagraph (E) of this subdivision are satisfied.

(i) NAPL is not present as determined in accordance with subdivision (4) of this subsection;

(ii) The water table is at least fifteen (15) feet above the surface of the bedrock; and

(iii) The downward vertical flow velocity of groundwater is equal to or less than the horizontal flow velocity.

(D) Conditions at the release area shall satisfy clause (i) or (ii) of this subparagraph.

(i) (I) A public water supply distribution system is available within two hundred (200) feet of the parcel on which the release area is located, within two hundred (200) feet of all adjacent parcels, and within two hundred (200) feet of any parcel within the areal extent of the groundwater plume from the subject release area;

(II) The groundwater within the areal extent of the groundwater plume from the subject release area is not used for drinking water;

(III) No public or private water supply wells exist within five hundred (500) feet of the subject release area; and

(IV) The groundwater affected by the subject release area is not a potential public water supply resource or in an aquifer protection area; or

(ii) The groundwater plume resulting from the subject release is a diminishing state groundwater plume and either:

(I) The concentration of any substance in the groundwater plume from the subject release area and within seventy-five (75) feet of the nearest downgradient parcel boundary is equal to or less than the groundwater protection criteria; or

(II) The concentration of any substance within the groundwater plume from the subject release area is equal to or less than the groundwater protection criteria for such substance at a location downgradient of the subject release area, on the subject parcel, and within twenty-five (25) feet of such release area .

(E) Written notice of the use of optional criteria calculated by an LEP under subparagraph (B) of this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs.

(3) Optional Criteria for Polluted Soil in a GB Area

(A) Polluted Soil in a GB Area

Provided that NAPL is not present in the release area above the seasonal high water table, as determined in accordance with subdivision (4) of this subsection, substances in soil in a GB area may be remediated to a concentration at which the results of a TCLP or SPLP analysis of each substance is equal to or less than the groundwater protection criteria:

(i) Multiplied by ten (10);

(ii) Multiplied by the ratio of the summation of the downgradient area and upgradient area compared to the release area, provided that such ratio is equal to or less than five hundred (500); or

(iii) Multiplied by an alternative dilution or dilution and attenuation factor approved in writing by the commissioner in accordance with subsection (d)(3) of this section.

(B) Optional Criteria Based Upon Release-Specific Dilution in a GB Area

(i) The criteria in this clause may only be used if the requirements in clauses (ii) and (iii) of this subparagraph are satisfied. Except for soil polluted with PCBs, substances in soil in a GB area may be remediated to a concentration at which the results of either:

(I) Mass analysis for each substance is equal to or less than the pollutant mobility criteria applicable to such substance in a GA area multiplied by a release-specific dilution factor calculated in accordance with clause (iv) of this subparagraph; or

(II) TCLP or SPLP analysis for each substance is equal to or less than the groundwater protection criterion for such substance multiplied by a release-specific dilution factor calculated in accordance with clause (iv) of this subparagraph.

(ii) Conditions at the subject release area comply with the following requirements:

(I) NAPL is not present above the seasonal high water table as determined in accordance with subdivision (4) of this subsection;

(II) The water table is at least fifteen (15) feet above the surface of the bedrock;

(III) The downward vertical flow velocity of groundwater is equal to or less than the horizontal flow velocity; and

(IV) For each substance in groundwater, the background concentration is equal to or less than the groundwater protection criteria.

(iii) Written notice of the use of optional criteria calculated by an LEP under this subparagraph shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and shall also include the calculation in clause (iv) of this subparagraph, value and basis of terms, and the till infiltration rate and dilution factor from the following table, based on the geologic material and infiltration rate.

Geologic Material	Infiltration Rate (feet/year)
Stratified Drift	2.0
Till	0.5 - 1.0
Lacustrine Deposits	0.4

(iv) The release-specific dilution factor referred to in clause (i) of this subparagraph, shall be calculated using the following formula, and the value of terms referred to in clause (i) of this subparagraph shall be calculated using the following formula:

Terms	Description	Value	Units
DF	Release-specific dilution factor	substance-specific	unitless
K	Hydraulic conductivity of the unconsolidated aquifer underlying the release area	calculated	ft/year
i	Horizontal hydraulic gradient	calculated	ft/ft
d	Aquifer mixing zone default value of 3 feet or a release-specific value calculated using: >	3, or as otherwise calculated	ft
d_α	Aquifer thickness	as determined from boring logs	ft
I	Infiltration rate, as identified in section 22a-133k-2(c)(3)(B)(iii)(IV) of the RSRs	calculated	ft/year
L	Length of the release area parallel to the direction of groundwater flow	as measured	ft
F_adj	Background concentration for groundwater divided by the groundwater protection criteria for the subject substance or, where the background concentration for groundwater cannot be quantified, one half the laboratory reporting limit for the subject substance divided by the groundwater protection criteria for the subject substance	calculated	unitless

(4) Determining the Presence of NAPL in Soil

For the purpose of this subsection, the presence of NAPL in soil shall be determined using either:

(A) The following equation where the variables in the equation are assigned the values in the Table following this equation:

Terms	Description	Units	Value
C_NAP	Concentration of an organic substance at which or above which such substance may be present in a non-aqueous phase	mg/kg	calculated
S	Effective solubility	mg/L	substance-specific
ρ_b	Dry soil bulk density	kg/L	1.5 or the lowest value measured at the subject release area
K_d	Soil-water partition coefficient, which is calculated using K_d = K_OC*f_OC	L/kg	calculated
K_OC	Soil organic carbon-water partition coefficient	L/kg	substance-specific
f_OC	Fraction organic carbon of soil	g/g	0.006 or the lowest value measured at the subject release area
θ_w	Water-filled soil porosity L_water/L_soil	L_water/L_soil	0.15 for unsaturated soil or 0.43 for saturated soil
θ_a	Air-filled soil porosity L_air/L_soil	L_air/L_soil	0.28 for unsaturated soil or 0.0 for saturated soil
H’	Henry’s law constant (dimensionless)	unitless	H x 41 where 41 is a conversion factor
H	Henry’s law constant	atm-m³/mol	substance-specific

(B) The commissioner may approve or deny in writing a request for an alternative to the equation in subparagraph (A) of this subdivision to determine the presence of NAPL in soil. Such proposed alternative methods may be based upon emerging technologies and approaches for which guidance, a standard, or an industrial code has been published by a regulatory agency, governmental advisory group, or other recognized professional organization. A request under this subdivision shall be submitted to the commissioner on a form prescribed by the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include any other information that the commissioner deems necessary to evaluate such request. Any approval by the commissioner may specify conditions necessary to protect human health and the environment.

(5) Conditional Exemptions to Pollutant Mobility Criteria

(A) Environmentally Isolated Soil

Polluted soil at a release area above the seasonal high water table is not required to be remediated to the pollutant mobility criteria, provided that:

(i) Such soil does not contain substances that are a continuing source of pollution;

(ii) Regardless of groundwater classification, if such soil contains volatile organic substances in excess of GA area pollutant mobility criteria, the concentrations of such substances have been reduced or immobilized to the maximum extent prudent;

(iii) An EUR is in effect for the subject area, which restriction shall:

(I) Prohibit infiltration of liquid into such soil; and

(II) Require compliance with clause (i) and, if applicable, clause (ii) of this subparagraph; and

(iv) The EUR specified in clause (iii) of this subparagraph shall also:

(I) Require that any building that renders soil environmentally isolated consists of a roof and structural walls that prevent infiltration of liquid into the soil beneath the building footprint, and prohibit removal of such building; or

(II) Require that the use of a permanent structure that renders soil environmentally isolated and prevents infiltration of liquid into the soil beneath the structure’s footprint has been approved in writing by the commissioner and prohibit the removal of such structure.

(B) Polluted Material

(i) Polluted material at a release area is not required to be remediated to the pollutant mobility criteria, provided that:

(I) The pollutant mobility criteria in such polluted material is exceeded solely as a result of the presence of coal ash, wood ash, coal fragments, coal slag, coal clinkers, asphalt paving fragments, or any combination thereof;

(II) Such polluted material is not polluted with any volatile organic substances that exceed the applicable pollutant mobility criteria,

(III) Such polluted material does not exceed the applicable soil vapor volatilization criteria, or if it does, all such polluted material is under a building in accordance with section 22a-133k-3(c)(3) of the RSRs, a permanent structure approved in writing by the commissioner, or an engineered control in compliance with subsection (f)(2)(B) of this section;

(IV) Such polluted material has achieved compliance with the direct exposure criteria in subsection (b) of this section;

(V) Such polluted material is not affecting and will not affect the quality of an existing use of groundwater, including, but not limited to, a potential public water supply resource or an aquifer protection area;

(VI) A public water supply distribution system is available within two hundred (200) feet of the parcel on which polluted material is located and within two hundred (200) feet of all parcels adjacent thereto; and

(VII) The placement of the polluted material used as fill was not prohibited by law at the time of placement.

(ii) This subparagraph shall apply only to polluted materials identified in clause (i) of this subparagraph and releases from such materials. It shall not apply to releases that are not from polluted materials, even if such releases are in the same location as the polluted materials identified in clause (i) of this subparagraph.

Polluted soil at a release area polluted with substances, other than volatile organic substances, that exceed DEC or PMC is not required to be remediated to the pollutant mobility criteria, provided that at such release area:

(i) Eighty (80) percent or more of the mass of the substances remaining at the release area has been subject to infiltration;

(ii) Infiltration was not obstructed by anthropogenic features, for at least five (5) years;

(iii) Groundwater monitoring complies with the requirements of section 22a-133k-3(h)(1) of the RSRs; and

(iv) The laboratory analytical results for all groundwater sample events collected as specified in section 22a-133k-3(h)(3) of the RSRs are equal to or less than the following:

(I) For a GA area, an aquifer protection area, or groundwater area used as a source for either a private or public drinking water supply located in a GB area, the groundwater protection criteria and the surface water protection criteria or, if applicable, the water quality criteria; or

(II) For a GB area, other than a GB area specified in subclause (I) of this clause, the surface water protection criteria or, if applicable, the water quality criteria.

(D) Conditional Exemption for Incidental Sources

Soil at a release area polluted with metals, petroleum hydrocarbons, or semi-volatile organic substances is not required to be remediated to the pollutant mobility criteria, provided such pollution is the result of:

(i) An incidental release due to the normal operation of motor vehicles, not including refueling, repair or maintenance of a motor vehicle; or

(ii) Normal paving and maintenance of a consolidated bituminous concrete surface provided such bituminous concrete surface has been maintained for its intended purpose.

(E) Conditional Exemption for Soil Polluted with Pesticides

Soil polluted with pesticides at a release area as a result of the application of pesticides at such release area is not required to be remediated to the pollutant mobility criteria, provided that a determination has been made that such pesticides are present solely as a result of the application of pesticides and:

(i) Compliance with the direct exposure criteria or the requirements in subsection (b)(6) of this section has been achieved; and

(ii) Compliance with the groundwater standards specified in section 22a-133k-3(a) of the RSRs or the requirements of section 22a-133k-3(g) of the RSRs has been achieved.

(6) Pollutant Mobility Criteria for Additional Polluting Substances

(A) Substances at a release area for which pollutant mobility criteria are not specified in Appendix B of the RSRs shall be remediated to background concentration or to criteria obtained pursuant to this subdivision. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A proposed risk-based pollutant mobility criteria for each substance calculated in accordance with Appendix G of the RSRs, as applicable to the groundwater classification of the release area;

(ii) A method for determining compliance with each criteria;

(iii) The laboratory reporting limit for each substance; and

(iv) Any information demonstrating whether a proposed criteria will ensure that soil water at such release area does not exceed:

(I) In a GA area, the groundwater protection criteria; or

(II) In a GB area, the groundwater protection criteria multiplied by a dilution factor of ten (10).

(B) The commissioner may approve or deny in writing a request made under subparagraph (A) of this subdivision. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the requirements of this subdivision have been satisfied and that the proposed pollutant mobility criteria will be protective of human health and the environment.

(d) Alternative Soil Criteria and Alternative Dilution or Dilution Attenuation Factor

(1) Information Required in a Request for Approval of Alternative Soil Criteria

A request for approval of the alternative direct exposure criteria or alternative pollutant mobility criteria at a particular release area may be submitted to the commissioner under this subsection. Any such request shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, including any additional information specified in subdivisions (2) or (3) of this subsection, as applicable, and shall also include:

(A) A detailed description of any other release area located on the same parcel as the subject release area and whether such other release area is affected or potentially affected by the subject release area, or is affecting or may potentially affect the subject release area; and

(B) When an EUR is required under this subsection, the acknowledgement and consent of the owner of the subject area to such alternative direct exposure criteria.

(2) Commissioner Approval of Alternative Release-Specific Direct Exposure Criteria

With respect to a substance, except PCBs, for which direct exposure criteria are specified in Appendix A of the RSRs or approved in writing by the commissioner pursuant to subsection (b)(7) of this section, the commissioner may approve or deny in writing a request for an alternative release-specific direct exposure criteria or an alternative method for determining compliance with such criteria.

(A) For substances in soil at a release area, no request shall be approved unless it is demonstrated to the commissioner’s satisfaction that:

(i) The application of such alternative direct exposure criteria or method of compliance will protect human health and the environment from the risks associated with direct exposure to polluted soil;

(ii) The concentration of each carcinogenic substance in such soil is equal to or less than a 1 X 10^-6 excess lifetime cancer risk level and the concentration of each non-carcinogenic substance in such soil does not exceed a hazard index of 1;

(iii) For a release area polluted with ten (10) or more carcinogenic substances, the cumulative excess lifetime cancer risk for all carcinogenic substances in such soil with the same target organ is equal to or less than 1 X 10^-5; and

(iv) For a release area polluted with ten (10) or more non-carcinogenic substances, the cumulative hazard index is equal to or less than 1 for non-carcinogenic substances in such soil with the same target organ.

(B) A request for approval of direct exposure criteria or method of compliance shall include a risk assessment prepared in accordance with the most recent EPA Risk Assessment Guidance for Superfund, or other risk assessment method approved by the commissioner.

(C) Any approval of the commissioner under this subdivision may require that an EUR is or will be in effect for the subject area, which restriction shall require compliance with any conditions specified by the commissioner when issuing such approval.

(3) Commissioner Approval of Alternative Release-Specific Pollutant Mobility Criteria

(A) Alternative Release-Specific Pollutant Mobility Criteria

With respect to substances for which pollutant mobility criteria are specified in Appendix B of the RSRs or approved by the commissioner pursuant to subsection (c)(6) of this section, the commissioner may approve or deny in writing a request for an alternative release-specific pollutant mobility criteria or an alternative method for determining compliance with such criteria. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the application of such alternatives:

(i) For a substance in soil located in a GA area, will ensure that soil water at such release area is equal to or less than the groundwater protection criteria for such substance; or

(ii) For a substance in soil located in a GB area, will ensure that the groundwater plume, after dilution resulting from infiltration on the parcel, is equal to or less than the groundwater protection criteria for such substance.

(B) Alternative Release-Specific Dilution or Dilution Attenuation Factor

With respect to substances for which pollutant mobility criteria are specified in Appendix B of the RSRs or approved by the commissioner pursuant to subsection (c)(6) of this section, the commissioner may approve or deny in writing a request for an alternative release-specific dilution or dilution attenuation factor. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the application of such dilution attenuation factor:

(i) For a substance in soil located in a GA area, will ensure that the release area will not degrade groundwater quality and thereby prevent the achievement of the groundwater criteria or background concentration, in accordance with section 22a-133k-3 of the RSRs; or

(ii) For a substance in soil located in a GB area, will ensure that the soil water at the release area will not cause the groundwater at the nearest downgradient parcel boundary to exceed the groundwater protection criteria for each substance.

For any request for approval of alternative pollutant mobility criteria or alternative dilution or dilution attenuation factor specified in this subdivision, alternative groundwater criteria shall not be used for the same substance for which alternative soil criteria is requested.

(4) LEP Calculation and Use of Alternative Release–Specific Pollutant Mobility Criteria

With respect to substances for which pollutant mobility criteria are specified in Appendix B of the RSRs, alternative release–specific pollutant mobility criteria for a particular release area may be calculated by an LEP in accordance with Appendix H of the RSRs and used at a release area, provided that:

(A) The calculated alternative pollutant mobility criteria shall not exceed one thousand (1,000) mg/kg in a GA area or ten thousand (10,000) mg/kg in a GB area;

(B) All representative laboratory analytical results of groundwater samples used to determine compliance with any such alternative criteria shall be conducted in accordance with section 22a-133k-3(h) of the RSRs. Alternative criteria under this subdivision shall not be used if any groundwater sample results are equal to or greater than:

(i) The groundwater protection criteria in Appendix C of the RSRs, if the subject release area is in a GA area, an aquifer protection area, or an area where groundwater is used as a source of either private or public drinking water supply;

(ii) Either the surface water protection criteria in Appendix D of the RSRs or, if required under section 22a-133k-3(a)(3) of the RSRs, the water quality criteria; and

(iii) The volatilization criteria in Appendix E of the RSRs; and

(C) Notice of the use and derivation of the calculated criteria is submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs.

(e) Determining Compliance with the Soil Criteria

(1) Direct Exposure Criteria

Unless an alternative method for determining compliance with direct exposure criteria has been approved in writing by the commissioner pursuant to subsection (d)(2) of this section, compliance with direct exposure criteria for each substance is achieved when either:

(A) All laboratory analytical results of soil samples from a release area are equal to or less than the applicable direct exposure criteria; or

(B) Except for PCBs, the ninety-five (95) percent upper confidence level of the arithmetic mean of a statistically representative sampling data set of all laboratory analytical results for such substance from a release area, consisting of ten (10) or more soil samples, is equal to or less than the applicable direct exposure criteria.

(2) Pollutant Mobility Criteria

Unless an alternative method for determining compliance with pollutant mobility criteria has been approved in writing by the commissioner pursuant to subsection (d)(3) of this section, compliance with pollutant mobility criteria for each substance is achieved when either:

(A) All laboratory analytical results of soil samples from a release area are equal to or less than the applicable pollutant mobility criteria; or

(B) Except for PCBs, the ninety-five (95) percent upper confidence level of the arithmetic mean of a statistically representative sampling data set of all laboratory analytical results for such substance from a release area, consisting of ten (10) or more soil samples that are located above the water table, is equal to or less than the applicable pollutant mobility criteria.

(3) Background Concentration

Compliance when remediating to the background concentration for a given substance in soil is achieved when:

(A) A representative sampling program is used to characterize the background concentration for soil that is:

(i) Of similar texture and composition;

(ii) Collected from the nearest location practicable outside the subject release area, as demonstrated to the satisfaction of the commissioner; and

(iii) Not affected by another discrete release of the same substance, or having an effect on the concentrations of the same substance for which a background concentration is determined; and either

(B) All laboratory analytical results of soil samples from the subject release area are equal to or less than the background concentration for soil; or

(C) A statistical comparison of the background concentrations in soil to the concentrations of substances in soil from the subject release area, results in a statistically significant similarity.

(f) Soil Criteria Variances

(1) Widespread Polluted Fill Variance

(A) Eligibility

Geographically-extensive polluted fill present at a parcel may be eligible for a variance from compliance with the pollutant mobility criteria in accordance with subparagraph (B) or (C) of this subdivision, provided that:

(i) The fill for which a variance is sought does not contain volatile organic substances in excess of pollutant mobility criteria;

(ii) Such fill is not affecting and will not affect the quality of an existing or potential public water supply resource or an existing private drinking water supply;

(iii) For each substance in such fill, compliance with the direct exposure criteria in subsection (b) of this section has been achieved;

(iv) Any substances released into such fill subsequent to the placement of such fill that exceed the pollutant mobility criteria shall be remediated to concentrations equal to or less than the concentrations of those substances already within such fill;

(v) The placement of such fill was not prohibited by law at the time of placement;

(vi) Such fill shall remain on the parcel within the area for which such variance has been certified by an LEP in accordance with subparagraph (B) of this subdivision or approved in writing by the commissioner in accordance with subparagraph (C) of this subdivision; and

(vii) The owner of the parcel for which a variance is sought acknowledges and consents to such variance and the EUR required by subparagraph (D) of this subdivision.

(B) LEP Certification of a Widespread Polluted Fill Variance

A variance for widespread polluted fill in accordance with this subdivision may be certified in writing by an LEP, provided such LEP determines that a parcel complies with the eligibility requirements in subparagraph (A) of this subdivision and the LEP demonstrates that the following requirements have been satisfied:

(i) Such fill extends over an area larger than ten (10) acres;

(ii) Such fill is located within the coastal boundary, as defined in section 22a-94(b) of the Connecticut General Statutes;

(iii) Such fill is located within a GB area;

(iv) Such fill is not located within the drainage basin of a Class A stream, as identified in the Water Quality Standards;

(v) Compliance with the groundwater standards in section 22a-133k-3 of the RSRs has been achieved for each substance in groundwater;

(vi) Such fill is not hazardous waste, as defined in section 22a-448 of the Connecticut General Statutes;

(vii) Except in the case of a municipality or state or federal agency, the person requesting the variance or the owner of the parcel subject to the variance did not place the fill on the subject parcel and is not affiliated with any person responsible for such placement through any direct or indirect familial relationship or any contractual, corporate, or financial relationship other than that by which such person’s or such owner’s interest in such parcel was conveyed or financed; and

(viii) Notice of the use of such variance shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs.

(i) Information demonstrating that a public water supply distribution system is available to all areas between the groundwater plume and the downgradient surface water discharge area;

(ii) The comparable cost of achieving compliance with pollutant mobility criteria without such variance;

(iii) The degree to which such fill exceeds pollutant mobility criteria;

(iv) The extent of such fill on the subject parcel that extends below the water table;

(v) The three-dimensional extent of such fill and the percentage of such fill occurring on the subject parcel; and

(vi) Information demonstrating that the person requesting the variance or the owner of the parcel subject to the variance did not place such fill on the subject parcel or is not affiliated with any person responsible for the placement of such fill through any direct or indirect familial relationship or any contractual, corporate or financial relationship other than that by which such person’s or such owner’s interest in such parcel is to be conveyed or financed.

(D) Actions Required for Maintaining a Widespread Polluted Fill Variance

(i) No later than one hundred and eighty (180) days after an LEP certifies a widespread polluted fill variance under subdivision (1)(B) of this subsection, an EUR that complies with the requirements of this subsection and the EUR regulations shall be in effect for the subject area, which restriction shall prohibit any movement or reuse of such fill in a manner that does not comply with the RSRs; or

(ii) No later than one hundred and eighty (180) days after a widespread polluted fill variance has been certified by an LEP or approved by the commissioner, a request for an ELUR or NAUL that complies with the requirements of this subsection and the EUR regulations shall be submitted to the commissioner. The EUR in effect for the subject area, shall:

(iii) Prohibit any movement or reuse of such fill in a manner that does not comply with the RSRs; and

(iv) Require compliance with any condition imposed by the commissioner when approving a variance under this section.

(2) Engineered Control Variance

(A) Eligibility

A release area may be eligible for a variance from compliance with the direct exposure criteria, the pollutant mobility criteria, or both, under this subdivision through the use of an engineered control, provided that:

(i) The commissioner authorized the disposal of solid waste or polluted soil at the subject release area;

(ii) The soil at such release area is polluted with a substance for which remediation is technically impracticable;

(iii) The commissioner has determined that the removal of such substance or substances from such release area would create an unacceptable risk to human health;

(iv) An LEP, pursuant to subparagraph (B) of this subdivision, has determined that the cost of remediating the polluted soil at the subject release area is significantly greater than the cost of installing and maintaining an engineered control for such soil and conducting groundwater monitoring that complies with section 22a-133k-3(h) of the RSRs at the subject release area; or

(v) The commissioner, pursuant to subparagraph (C) of this subdivision, has determined that the cost of remediating the polluted soil at the subject release area significantly outweighs the risk to the environment and human health if the engineered control fails, causing the mobilization of a substance in the soil or human exposure to such substance, and the cost of remediating the polluted soil at the subject release area is significantly greater than the cost of installing and maintaining an engineered control for such soil and conducting groundwater monitoring that complies with section 22a-133k-3(h) of the RSRs at the subject release area.

(B) LEP Certification of an Engineered Control Variance

A variance from compliance with the direct exposure criteria may be available when an engineered control is used at a release area, provided an LEP certifies to the commissioner, in accordance with section 22a-133k-1(g) of the RSRs, that the eligibility requirements of subparagraph (A) of this subdivision and the following requirements have been satisfied:

(i) The engineered control is designed and constructed and will be maintained to meet the following specifications, as applicable:

(I) For non-paved surfaces consisting of shallow-rooted vegetation, mulch, or gravel, there shall be a minimum of one (1) foot of material as measured from the ground surface, provided that the concentrations of any substances in such material are equal to or less than the applicable direct exposure criteria. Such material shall be underlain by a demarcation layer, unless there is a pre-existing mature lawn for a minimum of three (3) years;

(II) For non-paved surfaces consisting of shrubbery, such shrubbery shall be underlain by a minimum of eighteen (18) inches of material as measured from the ground surface, provided that the concentrations of any substances in such material are equal to or less than the applicable direct exposure criteria. Such material shall be underlain by a demarcation layer, unless there is pre-existing mature shrubbery;

(III) For non-paved surfaces consisting of trees, such trees shall be underlain by a minimum eighteen (18) inches of material, provided that the concentrations of any substances in such material are equal to or less than the applicable direct exposure criteria, measured vertically from the ground surface and extending horizontally to a radius equivalent to the full extent of the tree crown when mature. Such material shall be underlain by a demarcation layer, unless there are pre-existing trees;

(IV) For non-paved surfaces consisting of hardscape, a professional engineer shall sign and seal a plan and specifications indicating that the hardscape is appropriately designed to work for its intended use, with minimal maintenance and repair for fifteen (15) years, and is or shall be constructed with a minimum of nine (9) inches of a combined thickness of hardscape and sub-base. Such material shall be underlain by a demarcation layer, unless such hardscape is pre-existing;

(V) For paved surfaces, a professional engineer shall sign and seal a plan and specifications indicating that the engineered control is appropriately designed for such paved surface’s intended use, with minimal maintenance and repair for fifteen (15) years, and shall be constructed with a minimum of two and one-half (2.5) inches of bituminous concrete with a minimum of six (6) inches of sub-base or a minimum of four (4) inches of reinforced concrete. In addition any bituminous concrete or reinforced concrete less than five (5) feet wide or less than five hundred (500) square feet, the surface shall be underlain by a demarcation layer, unless such paved surface is pre-existing; or

(VI) For a ground-mounted solar array anchored by a concrete ballast, the concrete ballast for the solar array shall be underlain with a minimum of one (1) foot of material and all remaining infrastructure associated with the solar array installation shall consist of a minimum of two (2) feet of material, provided that any substances in such are equal to or less than the applicable direct exposure criteria and all such material is underlain by a demarcation layer;

(ii) PCBs are not present in the soil in excess of the residential direct exposure criteria;

(iii) Consolidation of polluted soil under an engineered control is such that the soil does not exceed four (4) feet above the pre-consolidation elevation;

(iv) Measures are in place to ensure that the structural integrity, function, and effectiveness of the engineered control will be maintained. Such measures shall include, without limitation:

(I) Measures to prevent storm run-on or run-off from damaging the engineered control;

(II) Inspection of the engineered control conducted semi-annually. Such inspections may be done in conjunction with and satisfy the inspection requirements in the EUR Regulations; and

(III) Repairs to correct the effects of settling, subsidence, erosion, or other damaging events or conditions no later than sixty (60) days following identification of damage to the engineered control, provided if weather prevents repairs from being made within sixty (60) days of the identification of damage, as long as temporary repairs or measures have been taken, repairs can be made as soon as the weather permits;

(v) The owner of the subject area on which such engineered control will be placed acknowledges and consents to such engineered control;

(vi) An EUR is or will be in effect for the subject area, which restriction shall:

(I) Prohibit the disturbance of the engineered control and the polluted soil; and

(II) Require compliance with the requirements of this subparagraph, except for clauses (vii) and (viii);

(vii) A copy of the required public notice that was posted in accordance with section 22a-133k-1(d) of the RSRs; and

(viii) Calculation of the required financial assurance in accordance with section 22a-133k-1(f) of the RSRs.

The commissioner may approve or deny in writing a request for a variance under this subsection. No request shall be approved unless such request demonstrates to the commissioner’s satisfaction that the eligibility requirements in subparagraph (A) of this subdivision and the requirements of this subparagraph have been met. A request for the commissioner’s approval of an engineered control variance shall be submitted in accordance with section 22a-133k-1(g) of the RSRs. Any such request shall include a demonstration of compliance with the eligibility requirements of subparagraph (A) of this subdivision and include a detailed written report and plan which demonstrate that:

(i) Such engineered control is supported by specifications that are signed and sealed by a professional engineer and indicate that such engineered control will function with minimum maintenance, will promote drainage and minimize erosion of or other damage to such control, and will accommodate settling and subsidence of the underlying soil so as to maintain the control’s functional integrity;

(ii) Measures are in place to ensure that the structural integrity, function, and effectiveness of the engineered control will be maintained. Such measures shall include, without limitation:

(I) Measures that ensure the continued effectiveness of the engineered control;

(II) Measures to prevent storm run-on or run-off from damaging the engineered control;

(III) Inspections, on a schedule approved by the commissioner. Such inspections may be done in conjunction with and satisfy the inspection requirements in the EUR Regulations; and

(IV) Repairs to correct the effects of any settling, subsidence, erosion or other damaging events or conditions no later than sixty (60) days following identification of damage to the engineered control, provided if weather prevents repairs from being made within sixty (60) days of the identification of damage, as long as temporary repairs or measures have been taken, repairs can be made as soon as the weather permits;

(iii) An EUR is or will be in effect for the subject area, which restriction shall:

(I) Prohibit any activity that could disturb either the engineered control or the polluted soil; and

(II) Except for clauses (iv) and (v) of this subparagraph, require compliance with the requirements of this subparagraph and with all conditions imposed by the commissioner when approving such variance under this subdivision;

(iv) A copy of the required public notice that was posted in accordance with section 22a-133k-1(d) of the RSRs;

(v) Calculation of the required financial assurance in accordance with section 22a-133k-1(f) of the RSRs;

(vi) The owner of the subject area on which such engineered control will be placed acknowledges and consents to such engineered control; and

(vii) In addition to clauses (i) to (vi), inclusive of this subparagraph:

(I) For a variance from direct exposure criteria, such engineered control shall be designed, constructed, and will be maintained, to physically isolate polluted soil from human contact with such soil;

(II) For a variance from pollutant mobility criteria, such engineered control shall be designed, constructed, and will be maintained, to minimize migration of liquids through polluted soil and reduce the permeability of such soil to a permeability of less than 10^-6 cm/sec and groundwater monitoring at the release area shall be adequate to ensure that any substance migrating from the release area will be detected. In addition, if a variance under this subclause includes volatile organic substances, such engineered control shall be designed, constructed, and will be maintained, to ensure that any soil vapor migrating from the subject release area complies with all applicable volatilization criteria in accordance with section 22a-133k-3(c)(3) of the RSRs;

(III) For an engineered control that includes immobilization, including, but not limited to, the immobilization of NAPL, such engineered control shall be designed, constructed, and will be maintained, to reduce the migration of contaminants from the subject area, achieve compliance with groundwater criteria, and reduce the permeability of such soil to a permeability of less than 10^-6 cm/sec or if permeability is reduced by immobilization that such permeability of impacted soil is approved in writing by the commissioner and at a minimum is adequate to immobilize contaminants in the soil to achieve compliance with applicable groundwater criteria; and

(IV) For an engineered control using paved surfaces or hardscape, the engineered control is based on specifications which demonstrate that the surface and sub-base materials are suitable for the intended use and are able to function with minimal maintenance and repair for fifteen (15) years and which specifications are signed and sealed by a professional engineer.

(D) Actions Required for Maintaining an Engineered Control Variance

After an engineered control has been certified by an LEP or approved by the commissioner pursuant to this subdivision, the following actions shall be taken within the timeframes prescribed:

(i) A Final Engineered Control Completion Statement shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, within one hundred and twenty (120) days from completion of construction of the engineered control. Such statement shall be accompanied by as-built drawings, signed and sealed by a professional engineer, and certified by an LEP to demonstrate that the engineered control complies with the requirements of this subdivision;

(ii) A financial assurance mechanism shall be established within one hundred and twenty (120) days of completion of construction of the engineered control. Such financial assurance shall comply with the requirements of section 22a-133k-1(f) of the RSRs; and

(iii) A request for an EUR that complies with the requirements of this subsection and the EUR regulations shall be certified by an LEP or submitted to the commissioner, as applicable within one hundred and eighty (180) days of completion of construction of the engineered control.

(E) If the commissioner approves a request for an engineered control variance, under this subdivision, any such approval may include any additional measures which the commissioner deems appropriate to protect human health and the environment. Nothing in this subdivision shall preclude the commissioner from taking any action the commissioner deems necessary to protect human health or the environment if an approved engineered control fails.

(3) Public Roadways Variance

(A) The commissioner may grant a variance from compliance with the direct exposure criteria, the pollutant mobility criteria, or both, for polluted soil at a release area beneath an existing public roadway. Such variance, if approved, shall apply only so long as such polluted soil is beneath the public roadway. A request for such a variance shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. Any such request shall also include a statement, in writing, from the entity that owns the public roadway, in which such entity acknowledges:

(i) Such entity’s understanding of and consent to the variance requested under this subdivision;

(ii) That the polluted soil under and within the public roadway remains subject to the RSRs, including, but not limited to, any conditions imposed by the commissioner when approving a variance under this subdivision; and

(iii) That if, at some future time, such public roadway is proposed to be removed, at least ninety (90) days before such public roadway is removed, notice of such removal shall be provided to the commissioner along with a proposed plan for the commissioner’s review and approval of the investigation and remediation of all polluted soil for which a variance was obtained under this subdivision.

(B) Polluted soil at a release area is not eligible for a variance under this subdivision unless such soil is beneath an existing roadway.

(C) The commissioner may approve or deny in writing a request for a variance under this subdivision. No request shall be approved unless such request demonstrates to the commissioner’s satisfaction that:

(i) The requirements of subparagraph (A) of this subdivision have been satisfied;

(ii) Removal of the polluted soil is neither feasible nor prudent; and

(iii) The granting of the variance will not endanger public health or the environment.

(D) The approval or any variance by the commissioner under this subdivision may include any conditions that the commissioner deems necessary to protect human health and the environment.

(g) Non-aqueous Phase Liquids

(1) NAPL shall be removed to the maximum extent practicable.

(2) The commissioner may approve or deny in writing a request for a variance from the requirement to remove NAPL to the maximum extent practicable in accordance with this subsection. No request shall be approved unless such request demonstrates to the commissioner’s satisfaction that the requirements of subdivision (3) of this subsection have been satisfied. A request for the approval under this subsection shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and shall include the acknowledgement and consent of all owners of the release area containing NAPL.

(3) A release area containing NAPL is eligible for a variance under this subsection only if:

(A) All NAPL for which a variance is sought has been contained or removed to the maximum extent prudent such that:

(i) There is no migration of such NAPL;

(ii) In the circumstance where NAPL contains PCBs, such PCBs shall be remediated in compliance with 40 CFR Part 761;

(iii) Compliance with applicable groundwater criteria for groundwater impacted by such NAPL has been achieved;

(iv) Where the NAPL contains volatile organic substances located at or above the seasonal low water table and is beneath a building without mitigation in accordance with section 22a-133k-3(c)(3) of the RSRs, compliance with volatilization criteria for soil vapor in accordance with section 22a-133k-3(c)(2) of the RSRs has been achieved; and

(B) An ELUR is or will be in effect for the subject area, which restriction shall:

(i) Except for ongoing remediation, prohibit the disturbance and exposure of NAPL;

(ii) Prohibit the construction of a building over such NAPL if there is NAPL containing volatile organic substances located at or above the seasonal low water table; and

(iii) Require compliance with subparagraph (A) of this subdivision.

(4) The requirements of this subsection shall not apply to NAPL subject to regulation under section 22a-449(d)-101 et seq. of the Regulations of Connecticut State Agencies. Any such NAPL shall remain subject to regulation under section 22a-449(d)-101 et seq. of the Regulations of Connecticut State Agencies.

(h) Use of Polluted Soil and Reuse of Treated Soil

Any soil excavated from or treated at a release area during remediation shall be managed as follows:

(1) Hazardous Waste

Treatment, storage, disposal and transportation of soil which is hazardous waste, as defined pursuant to section 22a-448 of the Connecticut General Statutes, shall be carried out in conformance with the provisions of sections 22a-449(c)-101 to 119, inclusive, of the Regulations of Connecticut State Agencies, and any other applicable law;

(2) Special Waste

In accordance with section 22a-209-8 of the Regulations of Connecticut State Agencies, the commissioner may authorize polluted soil, which is not hazardous waste, as defined in section 22a-448 of the Connecticut General Statutes, to be disposed of as special wastes, as defined in section 22a-209-1 of the Regulations of Connecticut State Agencies.

(3) Polluted Soil

To be reused in any manner, polluted soil shall comply with all requirements of the RSRs, shall not be placed below the water table, shall not be placed in an area subject to erosion, and shall comply with the requirements in subparagraph (A), (B) or (C) of this subdivision. Prior to the reuse of such soil, a notice or request for the reuse of such soil pursuant to subparagraph (A), (B) or (C) of this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. Any such notice or request shall also include a map showing the proposed location and depth of the placement of such soil, and shall also demonstrate compliance with subparagraph (A), (B), or (C) of this subdivision. The commissioner may approve or deny in writing any request submitted pursuant to subparagraph (B) or (C) of this subdivision. No request shall be approved unless such request demonstrates to the commissioner’s satisfaction, compliance with the requirements of subparagraph (B) or (C) of this subdivision, as applicable, and that the proposed reuse of soil is protective of human health and the environment.

(A) Polluted soil from a release area may be reused on the same parcel from which it was excavated by providing notice to the commissioner only if the following requirements are met:

(i) (I) If the soil to be reused is polluted with substances at concentrations that are all equal to or less than the applicable direct exposure criteria in Appendix A of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (b)(7) of this section and the applicable pollutant mobility criteria in Appendix B of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (c)(6) of this section, such soil may be reused at any location on such parcel; or

(II) If the concentration of any substance in such soil exceeds the GA area pollutant mobility criteria in Appendix B of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (c)(6) of this section, such soil may be reused only in a GB area and placed over soil and groundwater that has already been affected by a release; and

(ii) Any soil to be reused is not placed under a building, if the polluted soil contains volatile organic substances, other than volatile petroleum substances; and

(iii) Any soil to be reused does not contain PCBs.

(B) Polluted soil from a release area may be reused on the same parcel from which it was excavated, on a different parcel affected by the same release, or on an abutting parcel affected by a release of similar substances, only in the following circumstances:

(i) (I) If the polluted soil exceeds the direct exposure criteria or the pollutant mobility criteria applicable to the location on the parcel where the polluted soil will be reused or relocated, such polluted soil shall be rendered inaccessible pursuant to subsection (b)(3) of this section, environmentally isolated pursuant to subsection (c)(5)(A) of this section, or is subject to an engineered control pursuant to subsection (f)(2) of this section;

(II) If the polluted soil contains volatile organic substances, other than volatile petroleum substances, that are greater than the GA area pollutant mobility criteria in Appendix B of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (c)(6) of this section, or if such polluted soil is placed under a building that overlies a release area that has already been affected by a release of volatile organic substances, the requirements of section 22a-133k-3(c)(3) of the RSRs shall apply; or

(III) If the polluted soil contains PCBs, the commissioner has issued a written approval in accordance with section 22a-467 of the Connecticut General Statutes and subsection (f)(2) of this section; and

(ii) Prior to any reuse on an abutting parcel affected by the same release, or on a different parcel affected by a release of similar substances, written approval from the commissioner is required.

(C) Polluted soil from a release area may be reused on a parcel other than the parcel for which the polluted soil was excavated, only if prior to any reuse, the commissioner approves such reuse in writing and such soil to be reused:

(i) Is polluted with substances at concentrations equal to or less than the applicable direct exposure criteria in Appendix A of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (b)(7) of this section and the applicable pollutant mobility criteria in Appendix B of the RSRs or criteria otherwise approved by the commissioner pursuant to subsection (c)(6) of this section for the location on the parcel where the polluted soil will be relocated;

(ii) Is placed over soil and groundwater which has already been affected by a release of similar substances; and

(iii) Either:

(I) The cumulative depth of all reused polluted soil from all other parcels does not exceed four (4) feet above the pre-remedial grade; or

(II) The cumulative depth of all reused polluted soil from all other parcels does not exceed ten (10) feet, provided that a demonstration has been made to the commissioner’s satisfaction that the depth greater than four (4) feet is required for redevelopment purposes and all slopes are designed, created, and will be maintained to prevent erosion.

(4) Natural Soil

Polluted soil may be used at any parcel of land if:

(A) Any substance is present therein in concentrations not exceeding naturally-occurring conditions in soil at the release area from which such soil is removed; and

(B) No other substance is detectable in such soil at a concentration greater than its laboratory reporting limit.

(5) Polluted Soil Containing Pesticides

Notwithstanding the provisions of subdivision (3) of this subsection, the commissioner may approve or deny in writing a request for agricultural reuse of soil containing pesticides excavated on one parcel for reuse on another parcel. Any request regarding the reuse of soil under this subdivision shall be made to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and, if soil is being reused on a parcel different from the parcel from which it was excavated, shall include the acknowledgement and consent of the owner of the parcel receiving such soil. No reuse shall be approved under this subdivision unless the request for reuse demonstrates to the commissioner’s satisfaction that:

(A) The concentration of substances in soil to be reused is equal to or less than the direct exposure criteria and the pollutant mobility criteria for all substances, other than pesticides;

(B) Such soil to be reused is excavated only from the soil horizon at or near the surface in which an accumulation of humified organic matter is mixed with the mineral matter from which plants receive the most nutrients;

(D) The pesticides in the soil to be reused are the result of the application of pesticides in accordance with accepted practices at the time of application; and

(E) Such reuse is protective of human health and the environment.

(i) Additional Remediation of Polluted Soil

Nothing in the RSRs shall preclude the commissioner from taking any action necessary to prevent or abate pollution or to prevent or abate any threat to human health or the environment, including without limitation:

(1) Ecological Risk Assessment and Remediation

At any location at which, despite remediation in accordance with the RSRs, the commissioner determines that there is a potential ecological risk, the commissioner may require that an ecological risk assessment be conducted and that additional remediation be conducted to mitigate any risks identified in such assessment;

(2) Aquatic Life Assessment and Remediation

At any location at which polluted soil has eroded into a surface water body, the commissioner may require that the effect of such polluted soil on aquatic life be assessed and that remediation to protect or restore aquatic life and surface water quality from the effects of such polluted soil be undertaken; or

(3) Multiple Polluting Substances

At any location at which there is polluted soil containing multiple polluting substances, the commissioner may require additional remediation to ensure that the risk posed by such substances does not exceed:

(A) A cumulative excess lifetime cancer risk of 10 ^-5 for ten (10) or more carcinogenic substances with the same target organ; and

(B) A cumulative hazard index of 1 for non-carcinogenic substances with the same target organ.

(Effective January 30, 1996; Amended June 27, 2013; Amended February 16, 2021)

Sec. 22a-133k-3. Remediation Standards for Groundwater

Latest version.

(a) Groundwater Criteria

Unless otherwise specified in the RSRs, all substances in groundwater from a release shall be remediated to comply with the following, as applicable:

(1) Groundwater in a GA Area

Remediation of substances in groundwater in a GA area, including the portion of a groundwater plume migrating from a GB area into a GA area, shall result in the reduction of each substance to a concentration equal to or less than:

(A) The background concentration, except as provided in subsection (d) of this section, concerning groundwater protection criteria;

(B) Surface water protection criteria or background concentration; and

(2) Groundwater in a GB Area

Except for any portion of a groundwater plume migrating from a GB area into a GA area that is subject to the requirements of subdivision (1) of this subsection, remediation of substances in groundwater in a GB area shall result in the reduction of each substance to a concentration equal to or less than:

(A) (i) The surface water protection criteria and volatilization criteria; or

(ii) The background concentration; and

(B) The groundwater protection criteria, where the existing use of groundwater is for drinking or other purposes, until the use of such groundwater for drinking or other purposes is permanently discontinued.

(3) Groundwater Plume Discharging to a Low-Dilution Surface Water Body

(A) Remediation of substances in groundwater shall result in the reduction of each substance to a concentration equal to or less than the criteria set forth in subparagraph (B) of this subdivision where such plume discharges to:

(i) A wetland;

(ii) A tidal flat;

(iii) An intermittent watercourse; or

(iv) A location where the areal extent of such groundwater plume occupies more than one half of one percent, or other percentage approved in writing by the commissioner, of the upstream drainage basin of the surface water body to which such plume discharges. The percentage of the upstream drainage basin shall be measured from the intersection of the surface water body with such groundwater plume.

(B) Each substance in groundwater specified in subparagraph (A) of this subsection shall be remediated to a concentration that is either:

(i) Equal to or less than the applicable water quality criteria or, if there are no such criteria, to criteria approved by the commissioner in accordance with subsection (i)(2) of this section; or

(ii) Equal to or less than the alternative surface water protection criteria calculated by an LEP in accordance with subsection (b)(2) of this section or approved by the commissioner in accordance with subsection (b)(3) of this section.

(b) Alternative Surface Water Protection Criteria

With respect to substances in groundwater for which surface water protection criteria are specified in Appendix D of the RSRs or approved by the commissioner pursuant to subsection (i)(2) of this section, alternative surface water protection criteria may be calculated by an LEP or approved in writing by the commissioner, pursuant to this subsection. For each substance, only one subdivision of this subsection may be used to calculate or to request commissioner approval of alternative surface water protection criteria. In addition, the commissioner may approve an alternative method of demonstrating compliance with surface water protection criteria under this subsection.

(1) Groundwater Plume Discharge to a Watercourse

(A) For a substance in a groundwater plume that discharges to an inland surface watercourse classified as AA, A, or B in the Water Quality Standards, alternative surface water protection criteria may be calculated. Any such calculation shall be performed by multiplying the applicable water quality criteria or, if there are no such water quality criteria, the criteria approved by the commissioner pursuant to subsection (i)(2) of this section, by a dilution factor derived from the following equation:

Terms	Description	Value	Units
DF	Release-specific dilution factor	substance-specific	unitless
Q99	Daily stream flow equal to or exceeded on 99 percent of days in a year	waterbody-specific	ft³/sec
Q_plume	Average daily discharge of the subject groundwater plume: Q_plume = KiA	calculated	ft³/sec
K	Hydraulic conductivity	as measured	ft/sec
i	Hydraulic gradient	as measured	ft/ft
A	Area of discharge: A = h * w	as measured	ft²
h	Thickness of groundwater plume at watercourse discharge area	as measured	ft
w	Width of groundwater plume at watercourse discharge area	as measured	ft

(B) For a substance in a groundwater plume that discharges to a coastal surface watercourse classified as SA or SB in the Water Quality Standards, alternative surface water protection criteria may be calculated. Any such calculation shall be performed by multiplying the applicable water quality criteria, or if there are no such water quality criteria, the criteria approved by the commissioner pursuant to subsection (i)(2) of this section, by a dilution factor derived from the following equation:

Terms	Description	Value	Units
D	Mean depth of the watercourse at mean low tide where the groundwater plume discharges	calculated	ft
DF	Release-specific dilution factor	substance-specific	unitless
L	Distance along which the groundwater plume intersects the watercourse discharge area	calculated	ft
W	Cross-sectional distance from one shoreline to the other for the tidally influenced watercourse under low tide conditions (0.25*watercourse width) where the maximum value for W is 100 feet	calculated	ft
T	Daily discharge duration	0.5	day
Q_plume	Average daily discharge of the subject groundwater plume: Q_plume = KiA	calculated	ft³/sec
K	Hydraulic conductivity	as measured	ft/day
i	Hydraulic gradient	as measured	ft/ft
A	Area of discharge: A = h * w	as measured	ft²
h	Thickness of groundwater plume at watercourse discharge area	as measured	ft
w	Width of groundwater plume at watercourse discharge area	as measured	ft

(C) For purposes of this subdivision, no alternative surface water protection criteria shall exceed the maximum allowable alternative surface water protection criteria specified in the table below, which is the water quality criteria multiplied by a dilution factor calculated pursuant to subparagraph (A) or (B) of this subdivision.

Distance from compliance point to nearest downgradient surface water	Maximum Allowable Alternative SWPC
Less than or equal to 100 feet	100 times WQC
Greater than 100 feet to 200 feet	200 times WQC
Greater than 200 feet to 300 feet	300 times WQC
Greater than 300 feet to 400 feet	400 times WQC
Greater than 400 feet to 500 feet	500 times WQC
Greater than 500 feet to 600 feet	600 times WQC
Greater than 600 feet to 700 feet	700 times WQC
Greater than 700 feet to 800 feet	800 times WQC
Greater than 800 feet to 900 feet	900 times WQC
Greater than 900 feet	1,000 times WQC

(D) Written notice of the use of alternative surface water protection calculated by an LEP under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and shall also include the calculation, value and basis of terms, and dilution factor used.

(2) Aquifer Dilution

(A) Alternative surface water protection criteria may be calculated in accordance with subparagraph (B) of this subdivision, provided that:

(i) The portion of the groundwater plume for which such alternative criteria are calculated is at least five hundred feet from the nearest downgradient surface water; and

(ii) A dilution ratio for such groundwater plume is calculated pursuant to the following equation, and such ratio is equal to or greater than five:

DR = RC/DC

Terms	Description	Value	Units
DR	Release-specific dilution ratio	calculated	unitless
RC	Groundwater concentration of a substance within the release area	as measured	µg/L
DC	Groundwater concentration no more than fifty feet downgradient from the location where the RC was collected	as measured	µg/L

(B) For substances in a groundwater plume that comply with subparagraph (A) of this subdivision, alternative surface water protection criteria shall be calculated by multiplying the surface water protection criteria, or if applicable the water quality criteria, by the dilution factor identified in the following table:

Distance to nearest downgradient surface water	Dilution factor
Greater than 500 feet to 600 feet	5
Greater than 600 feet to 700 feet	6
Greater than 700 feet to 800 feet	7
Greater than 800 feet to 900 feet	8
Greater than 900 feet to 1000 feet	9
Greater than 1000 feet	10

(C) Written notice of the use of alternative surface water protection criteria calculated by an LEP under this subparagraph shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and shall also include the calculation, value and basis of terms, and dilution factor used.

(3) Commissioner Approval

The commissioner may approve or deny in writing a request for a release-specific alternative surface water protection criteria or an alternative method of demonstrating compliance with surface water protection criteria. No request under this subdivision shall be approved until it is demonstrated to the commissioner’s satisfaction that such alternative criteria or alternative method for demonstrating compliance will protect all existing and proposed uses of surface water and is protective of human health and the environment. A request for such approval shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. Upon receipt of such request the commissioner shall specify which of the following shall be provided to the commissioner:

(A) The Q99 stream flow rate of the surface water body into which the subject groundwater plume discharges;

(B) The identification of other surface water or groundwater discharges to the surface water body within one-half mile of the areal extent of the subject groundwater plume;

(C) A report on the instream water quality into which the subject groundwater plume discharges, including assessment and use attainment information in the most current integrated water quality report and any applicable total maximum daily loads; and

(D) The flow rate of the subject groundwater plume that discharges to the surface water body and the extent and degree of mixing of such discharge in such surface water.

(1) Volatilization Criteria for Groundwater

(A) Residential Volatilization Criteria

Unless otherwise specified in this subsection, each volatile organic substance in groundwater shall be remediated to a concentration that is equal to or less than the residential volatilization criteria for groundwater.

(B) Industrial/Commercial Volatilization Criteria

Each volatile organic substance in groundwater may be remediated to a concentration that is equal to or less than the industrial/commercial volatilization criteria for groundwater, provided that the subject area above the groundwater polluted with volatile organic substances:

(i) Is not used for residential activity;

(ii) Has limited access only to those individuals working at or temporarily visiting for industrial/commercial activity; and

(iii) An EUR is in effect for the subject area or the entire parcel, which restriction shall:

(I) Prohibit residential activity; and

(II) Require compliance with clause (ii) of this subparagraph.

Subdivision (1) of this subsection shall apply to:

(i) Volatile organic substances, other than volatile petroleum substances, within thirty (30) feet or less of the ground surface and within thirty (30) feet or less of the lowest portion of a building under which groundwater is polluted with such substances; and

(ii) Volatile petroleum substances, within ten (10) feet or less of the ground surface and within ten (10) feet or less of the lowest portion of a building under which groundwater is polluted with such substances.

(2) Alternative Demonstration of Compliance with Volatilization Criteria for Groundwater

(A) Soil Vapor Below a Building

For volatile organic substances in groundwater, remediation to the volatilization criteria specified in subdivision (1) of this subsection may not be required if the concentration of such substances in soil vapors below a building is equal to or less than:

(i) The residential volatilization criteria for soil vapor; or

(ii) The industrial/commercial volatilization criteria for soil vapor, provided that to use such criteria, the requirements of subdivision (1)(B) of this subsection are satisfied.

(B) Concentrations at the Water Table

For volatile organic substances in groundwater, remediation to the volatilization criteria specified in subdivision (1) of this subsection may not be required if the substances in groundwater exceeding volatilization criteria are not at the water table and all of the laboratory analytical results from sampling the concentration of such substances at the water table, as seasonally demonstrated by groundwater monitoring representative of the uppermost portion of the water column are equal to or less than:

(i) The residential volatilization criteria for groundwater; or

(ii) The industrial/commercial volatilization criteria for groundwater, provided that to use such criteria, the requirements of subdivision (1)(B) of this subsection are satisfied.

(3) Exemption from Volatilization Criteria for Groundwater through Vapor Mitigation

For volatile organic substances in groundwater beneath an existing building, remediation to the volatilization criteria for groundwater specified in subdivision (1) of this subsection may not be required, provided that:

(A) Measures to prevent the migration of volatile organic substances into any overlying building have been implemented and submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. The submittal shall also include:

(i) A brief description of the measures implemented to control the migration of such volatile organic substances into any overlying building;

(ii) A demonstration of the effectiveness of such control measures;

(iii) The plan for monitoring the effectiveness of such control measures over time and maintaining such control measures in good condition; and

(iv) A map showing all existing buildings, the areal extent of the groundwater plume, and the location of such control measures;

(B) The commissioner deems the measure proposed under subparagraph (A) of this subdivision acceptable and such measures have been and continue to be implemented and monitored; and

(C) An EUR, or other permanent control measures approved in writing by the commissioner, is or will be in effect for the subject area, which restriction or control measure shall:

(i) Prohibit removal of any building above such volatile organic substances in groundwater; and

(ii) Require compliance with:

(I) Control measures deemed acceptable by the commissioner under subparagraphs (A) and (B) of this subdivision; and

(II) Any condition specified by the commissioner in the approval of such permanent control measures under this subparagraph.

(4) Alternative Release-Specific Volatilization Criteria and Alternative Method of Demonstrating Compliance with Volatilization Criteria

With respect to volatile organic substances in groundwater or soil vapor for which volatilization criteria are specified in Appendix E or Appendix F of the RSRs or approved by the commissioner pursuant to subsection (i)(3) of this section, the commissioner may approve or deny in writing a request for a release-specific alternative volatilization criteria. In addition, the commissioner may approve or deny in writing an alternative method of determining compliance with such criteria.

(A) A request for approval of alternative volatilization criteria or for an alternative method of demonstrating compliance with volatilization criteria shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A description of the distribution and concentration of volatile organic substances in groundwater or soil vapor beneath any overlying building;

(ii) A description of any site-specific conditions, including, but not limited to, the value of all terms used and the source of any release-specific values.

(B) No request under subparagraph (A) of this subdivision shall be approved unless such request demonstrates to the commissioner’s satisfaction that such criteria or alternative method of determining compliance is protective of human health and will ensure that volatile organic substances in groundwater or soil vapor do not accumulate in the air of any building at a concentration which:

(i) For any carcinogenic substance, creates a risk to human health in excess of a 10^-6 excess lifetime cancer risk level, and for any non-carcinogenic substance, is equal to or less than a hazard index of one (1); and

(ii) For a groundwater plume or soil vapor polluted with ten (10) or more volatile organic substances, does not exceed a cumulative excess cancer risk level of 10^-5 for carcinogenic substances, and for non-carcinogenic substances with the same target organ, the cumulative hazard index does not exceed one (1).

(C) Any approval of the commissioner under this subdivision, may require that an EUR is or will be in effect for the subject area, which restriction shall require compliance with any conditions specified by the commissioner when issuing such approval.

(5) Exemption from Volatilization Criteria for Groundwater Through a No Build Restriction

For volatile organic substances in groundwater, remediation to the applicable volatilization criteria specified in subdivision (1) of this subsection may not be required if the following conditions are satisfied:

(A) The water table is less than thirty (30) feet below the ground surface;

(B) No building exists over the groundwater polluted with such substances at a concentration above applicable volatilization criteria;

(i) An EUR is in effect for the subject area, which restriction shall;

(I) Prohibit construction of a building at the subject area; and

(II) Require compliance with subparagraph (B) of this subdivision;

(ii) The commissioner has approved in writing a request demonstrating that no building can reasonably be expected to be constructed over the subject groundwater; or

(iii) The commissioner has approved in writing a request demonstrating that natural attenuation or other methods of remediation will, within five (5) years, reduce the concentration of volatile organic substances in such groundwater to a concentration equal to or less than:

(I) Residential volatilization criteria; or

(II) The industrial/commercial volatilization criteria, in which case subdivision (1)(A)(ii) of this subsection shall apply; and

(D) For any volatile organic substances, other than volatile petroleum substances, that exceed the applicable volatilization criteria within thirty (30) feet of any part of a building, the potential for a vapor intrusion pathway into such building shall be thoroughly evaluated. If such evaluation identifies a vapor intrusion pathway into such building, compliance with subdivision (3) of this subsection shall be required.

(6) Exemption from Volatilization Criteria Through Indoor Air Monitoring

For volatile organic substances in groundwater, remediation to the applicable volatilization criteria specified in subdivision (1) of this subsection may not be required for groundwater underlying an existing building. No request under subparagraph (A) of this subdivision shall be approved unless such request demonstrates to the commissioner’s satisfaction that the conditions in the building overlying volatile organic substances in groundwater are protective of human health and the environment.

(A) A request in accordance with this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) The acknowledgement and consent of the owner of the building for which approval of the air monitoring program is sought; and

(ii) An indoor air monitoring program and measures to control the level of any such volatile organic substances in the air of the subject building, including, but not limited to:

(I) A description of the distribution and concentration of volatile organic substances beneath the building;

(II) Any measures to be taken;

(III) The location of proposed monitoring points;

(IV) The proposed frequency of monitoring;

(V) The parameters to be monitored; and

(VI) The actions to be taken in the event such monitoring indicates that selected parameters are exceeded.

(B) The commissioner may approve or deny in writing a request submitted under this subdivision. Approval of any indoor air monitoring program pursuant to this subdivision shall require that an ELUR is or will be in effect for the subject area, which restriction shall require compliance with the indoor air monitoring program approved by the commissioner in writing, including any conditions imposed by the commissioner when approving such program.

(7) For the purpose of this subsection, “building” means any structure enclosed by a roof and walls that is capable of accumulating vapors from the subsurface.

(d) Groundwater Protection Criteria

(1) Exemption from Attaining Background Concentration in a GA Area

For substances in groundwater in a GA area, remediation to the background concentration may not be required if the concentration of each substance in a groundwater plume is equal to or less than the groundwater protection criteria and one of the following conditions exist:

(A) (i) A public water supply distribution system is available within two hundred (200) feet of the parcel on which the release area is located, within two hundred (200) feet of all adjacent parcels, and within two hundred (200) feet of any parcel within the areal extent of the groundwater plume;

(ii) Such groundwater plume is not located in an aquifer protection area; and

(iii) Such groundwater plume is not located within the area of influence of any public water supply well;

(B) Prior to any soil or groundwater remediation, the groundwater plume is a diminishing state groundwater plume; or

(C) Each substance in groundwater is remediated to a concentration equal to or less than the groundwater protection criteria, and further reduction of the concentrations of such substances to the background concentration cannot be achieved using sound engineering and hydrogeologic remediation practices.

(2) Alternative Groundwater Protection Criteria

With respect to substances in groundwater for which groundwater water protection criteria are specified in Appendix C of the RSRs, or approved by the commissioner pursuant to subsection (i)(1) of this section, alternative groundwater protection criteria may be calculated by an LEP pursuant to subdivision (3) of this subsection or approved in writing by the commissioner pursuant to subdivision (4) or (5) of this subsection.

(3) LEP Calculation of Alternative Groundwater Protection Criteria

(A) For a substance in groundwater located in an area designated on the department’s “Potential Alternative Groundwater Protection Criteria Map” in Appendix I of the RSRs, alternative groundwater protection criteria may be calculated by an LEP, in accordance with subparagraph (B) or (C) of this subdivision, as applicable, provided that:

(i) Written notice of the use of alternative groundwater protection criteria is submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and any such notice includes:

(I) The alternative groundwater protection criteria calculation in accordance with subparagraph (B) or (C) of this subdivision; and

(II) Documentation demonstrating compliance with the requirements of this subdivision, including, but not limited to, a water supply well receptor survey;

(ii) Any alternative groundwater protection criteria shall not exceed:

(I) One hundred (100) times the groundwater protection criteria specified in Appendix C of the RSRs or approved by the commissioner in accordance with subsection (i)(1) of this section; and

(II) The residential volatilization criteria for groundwater specified in Appendix E of the RSRs or approved by the commissioner in accordance with subsection (i)(3) of this section;

(iii) No public or private drinking water supply well is present on any subject parcel within or adjacent to the areal extent of the portion of the subject groundwater plume in which a substance exceeds the background concentration;

(iv) A public water supply distribution system is available within five hundred (500) feet downgradient and two hundred (200) feet in any direction of the subject groundwater plume;

(v) All releases to soil that constitute a source of pollution resulting in the subject groundwater plume have been remediated so there is no longer an on-going source in soil impacting groundwater;

(vi) No alternative pollutant mobility criteria is used for the same substance for which an alternative groundwater protection criteria is used;

(vii) The subject groundwater plume is a diminishing state groundwater plume; and

(viii) The alternative groundwater protection criteria being calculated is not used for any portion of the subject groundwater plume located in bedrock unless approved by the commissioner in accordance with subdivision (5) of this subsection.

(B) For volatile organic substances, the following equation shall be used to calculate alternative groundwater protection criteria in accordance with this subdivision:

Terms	Description	Value	Units
Alternative GWPC	Criteria in groundwater as alternative to groundwater protection criteria	calculated	µg/L
TAC	Target Indoor Air Concentration as approved by the commissioner in accordance with Appendix G of the RSRs	substance-specific	µg/m³
f	Fraction of substance concentration volatilized	0.5	unitless
HV	House Volume	1,000	m³
ER	Air exchange rate per day, as a time weighted average	134	times per day
MC	Mixing coefficient	0.33	none
WFR	Water Flow Rate	3,183	L/day

(C) For semi-volatile organic substances, inorganic substances and pesticides, the following equation shall be used to calculate alternative groundwater protection criteria in accordance with this subdivision:

Terms	Description	Value	Units
Alternative GWPC	Criteria in groundwater as alternative to groundwater protection criteria	calculated	µg/L
WSF	Water to soil concentration factor, based upon accumulation of arsenic in soil	0.02	(mg/L)/ (mg/kg)
RSC	Relative source contribution to account for other background contributions to semi-volatile organic substances in soil	0.2	unitless
DEC	Residential direct exposure criteria in Appendix A of the RSRs or criteria approved by the commissioner pursuant to section 22a-133k-2(b)(7) of the RSRs	substance-specific	mg/kg
UCF	Unit Conversion Factor	1,000	µg/mg

(4) Commissioner Approval of Alternative Groundwater Protection Criteria Not In Mapped Areas

For a substance in groundwater that is not located in an area designated on the department’s “Potential Alternative Groundwater Protection Criteria Map” in Appendix I of the RSRs, the commissioner may approve or deny in writing a request for an alternative groundwater protection criteria pursuant to this subparagraph. A request for such alternative groundwater protection criteria shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. No request shall be approved unless such request demonstrates to the commissioner’s satisfaction:

(A) Compliance with the requirements of clauses (i) to (viii), inclusive, of subdivision (3)(A) of this subsection;

(B) Calculation of proposed alternative groundwater protection criteria in accordance with subparagraphs (B) and (C) of subdivision (3) of this subsection, as applicable; and

(i) Documentation from a public or private water company subject to regulation by the Department of Public Health demonstrating that public drinking water is available in the area where the subject groundwater plume is located, including a public water service area map on file with the Department of Public Health indicating that public water is available. This clause can be used only if:

(I) A public water supply distribution system has become available to any parcel within or adjacent to the areal extent of the portion of the groundwater plume not previously included on the department’s “Potential Alternative Groundwater Protection Criteria Map” in Appendix I of the RSRs; and

(II) The subject groundwater plume is not located in an aquifer protection area or in an aquifer suitable for development of a public water supply.

(ii) As a result of stratified drift aquifer conditions where the subject groundwater plume is located:

(I) The aquifer is not suitable for development of a public water supply due to the hydrogeology, depth, saturated thickness of the surficial materials or other hydrogeologic factors;

(II) There is less than twenty (20) feet of saturated sand or sand and gravel in such aquifer or pumping more than fifteen (15) gallons per minute from such aquifer is not sustainable for public water use; and

(III) A cross-sectional map is provided showing the nature and distribution of surficial materials in such aquifer.

(5) Commissioner Approval of Alternative Groundwater Protection Criteria Where Any Portion of a Plume Is In Bedrock

For a substance in groundwater that is located in an area designated on the department’s “Potential Alternative Groundwater Protection Criteria Map” in Appendix I of the RSRs, and where the portion of the groundwater plume is located in bedrock. A request for such alternative groundwater protection criteria shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs. No request shall be approved unless such request includes a map showing the horizontal and vertical extent of the bedrock groundwater plume that exceeds or could be expected to exceed the groundwater protection criteria and demonstrates to the commissioner’s satisfaction:

(A) Compliance with the requirements of clauses (i) to (vii), inclusive, of subdivision (3)(A) of this subsection; and

(B) That the groundwater plume that exceeds the groundwater protection criteria will not pose a risk to human health and the environment.

(e) Technical Impracticability Variance

Groundwater may be eligible for a variance from compliance with the surface water protection criteria or the groundwater protection criteria if the commissioner determines that compliance with such criteria is technically impracticable. No request for a variance shall be approved unless such request demonstrates to the commissioner’s satisfaction that the requirements of this subsection have been satisfied.

(1) Request for Technical Impracticability Variance

(A) A request for a technical impracticability variance shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) The substance and its concentration in the groundwater plume for which a variance is sought;

(ii) A map showing the horizontal and vertical extent of the groundwater plume that exceeds or could be expected to exceed surface water protection criteria or groundwater protection criteria;

(iii) A demonstration of compliance with the soil standards in section 22a-133k-2 of the RSRs, and unless it is demonstrated that remediation of soil is technically impracticable, that polluted soil is not contributing to the groundwater plume;

(iv) Laboratory analytical results of all representative sampling before, during, and after the implementation of such actions and a description of all actions to remediate the groundwater plume;

(v) A feasibility study for achieving compliance with the criteria for which a variance is sought that evaluates remediation methods and demonstrates that achieving compliance with such criteria in a reasonable timeframe is technically impracticable;

(vi) A demonstration that the subject groundwater plume is in a steady-state or is a diminishing state groundwater plume, or that the subject groundwater plume is hydraulically controlled;

(vii) A map and description of the proposed TI zone, including the identification of existing groundwater withdrawals and potential for future withdrawal of groundwater on parcels within and adjacent to the proposed TI zone, and a demonstration that such withdrawals will not induce movement of the subject groundwater plume into uncontaminated areas or adversely affect the protectiveness of the proposed variance;

(viii) A study to determine the risks posed by the polluted groundwater that would remain if a variance was granted. If such study shows a risk or a potential risk to human health or the environment, a contingency plan to eliminate or minimize such risk shall be included;

(ix) Measures for long-term monitoring, operation, maintenance, and reporting, to ensure that the selected remedy remains effective in its protectiveness. Such measures shall:

(I) Demonstrate through groundwater monitoring that the groundwater plume is not increasing in size or concentration, or otherwise migrating in a manner that would alter the risk assumptions of clause (viii) of this subparagraph;

(II) Confirm that unacceptable risks to human health and the environment do not occur and if such risks do occur, contingency actions will be taken to abate such risks, including, but not limited to, changes in land use; and

(III) Demonstrate through monitoring that any proposed operation and maintenance controls are working properly and remain effective; and

(x) The type and estimated amount of financial assurance to be posted in accordance with the requirements of section 22a-133k-1(f) of the RSRs.

(B) Based upon the information submitted in accordance with subparagraph (A) of this subdivision, the commissioner shall indicate, in writing, either that a groundwater plume does not qualify for a variance under this subsection, or alternatively, that the information specified in subdivision (2) of this subsection shall be submitted and may include conditions the commissioner deems appropriate to protect public health and the environment.

(2) Additional Information to be Submitted Upon Request

After submission of the information required in this subdivision, the commissioner may approve or deny in writing a request for a technical impracticability variance. Unless otherwise specified by the commissioner, the following information shall be submitted within one hundred and twenty (120) days of a request for such information by the commissioner. The information shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(A) A demonstration that public notice has been provided in accordance with section 22a-133k-1(d) of the RSRs;

(B) A certification that written notice of the extent and degree of such pollution allowed to remain in place has been provided to each owner of record of each parcel within the TI zone, at the address for such owner on the last-completed grand list of the municipality where the parcel is located, and to the Director of Health of the municipality or municipalities in which the TI zone is located;

(C) If the commissioner has specified that an ELUR is required, the acknowledgement and consent from the owner of each parcel in the TI zone to such variance;

(D) A demonstration that financial assurance has been obtained in accordance with section 22a-133k-1(f) of the RSRs; and

(E) A demonstration, as specified by the commissioner in the written request for information under this subdivision, that either an ELUR is in effect on each parcel in the TI zone or other permanent control measure is in place. Any ELUR or other permanent control measure shall:

(i) Require compliance with the plan and measures specified in clauses (viii) and (ix) of subdivision (1)(A) of this subsection;

(ii) Include conditions the commissioner deems appropriate to protect public health and the environment;

(iii) In addition to any requirement in the EUR Regulations, require the preparation of a report every five (5) years, which reviews the implementation and effectiveness of the variance approved by the commissioner, including, but not limited to, the impact of the use of groundwater on parcels adjacent to the TI zone. Such reports shall be maintained by the parcel owner who is requesting such variance until the technical impracticability variance is no longer required under this subsection and shall be provided to the commissioner upon request; and

(iv) In addition, for a variance from compliance with the groundwater protection criteria:

(I) Prohibit the use of groundwater for drinking or other purposes; and

(II) Prohibit the withdrawal of groundwater, unless a withdrawal has been approved in writing by the commissioner.

(f) Conditional Exemption for Incidental Sources

Compliance with the groundwater criteria specified in subsection (a) of this section is not required for the following substances in groundwater under the circumstances described in this subsection:

(1) Trihalomethanes or any other substance within drinking water released from a public water supply distribution system; or

(2) Metals, petroleum hydrocarbons, or semi-volatile organic substances, provided such substances are the result of:

(A) An incidental release due to the normal operation of motor vehicles, not including refueling, repair or maintenance of a motor vehicle; or

(B) Normal paving and maintenance of a consolidated bituminous concrete surface provided such bituminous concrete surface has been maintained for its intended purpose.

(g) Conditional Exemption for Groundwater Polluted with Pesticides

Compliance with the groundwater criteria specified in subsection (a) of this section is not required for pesticides in groundwater resulting from the application of pesticides at the release area, provided that:

(1) A determination has been made that such pesticides are present solely as a result of the application of pesticides;

(2) Compliance with the soil standards in section 22a-133k-2 of the RSRs has been achieved for any release of pesticides;

(3) The nature and approximate extent of pesticides in the groundwater has been evaluated;

(4) Potable water supply wells on the parcel where pesticides are in groundwater have been sampled and any exposure pathway to drinking water in such wells is eliminated or mitigated to the extent necessary to protect human health;

(5) A potable water supply well receptor survey identifying surrounding drinking water uses has been conducted;

(6) With respect to the parcel for which a demonstration of compliance with the RSRs is being made, if pesticides in the groundwater on such parcel exceed the groundwater criteria a notice is recorded on the municipal land records identifying such exceedance;

(7) If pesticides applied at a parcel, for which a demonstration of compliance with the RSRs is being made, are present in groundwater on other parcels at concentrations exceeding the groundwater criteria, best efforts have been made to ensure that an EUR has been placed providing notice that pesticides in groundwater on such affected parcels exceeds the groundwater criteria. A certification stating such best efforts have been made shall be submitted with the notice required under subdivision (8) of this section; and

(8) Notice of compliance with the requirements of this subsection, including all documents demonstrating such compliance, is submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and is also submitted to the Director of Health of the municipality in which such pesticides in groundwater are located.

(h) Applying the Groundwater Criteria

Compliance with the standards for groundwater in this section, or standards specified in section 22a-133k-2 of the RSRs that refer to or require groundwater monitoring, shall be based upon groundwater monitoring conducted in compliance with this subsection.

(1) Groundwater monitoring shall be capable of determining:

(A) The conceptual site model for the release is valid;

(B) The background concentration at the nearest location upgradient of and unaffected by the release;

(C) The effectiveness of any soil remediation to prevent the pollution of groundwater by substances from the release area;

(D) The effectiveness of any measures to render soil environmentally isolated;

(E) The effectiveness of any remediation to eliminate or minimize any risks to human health and the environment associated with each release being remediated, including, but not limited to, any risks identified during remediation or identified in any risk assessment conducted in accordance with subsection (e)(2) of this section;

(F) Whether the concentration of a substance in groundwater is equal to or less than the applicable groundwater criteria for such substance;

(G) Whether a ground-water groundwater plume in a GB area interferes with any existing use of groundwater, including, but not limited to, a drinking water supply or an industrial, agricultural, or commercial use of groundwater; and

(H) The effectiveness of monitored natural attenuation to achieve compliance with groundwater criteria within a reasonable timeframe.

(2) Pre-requisites for Determining Compliance with Groundwater Criteria

The groundwater samples that will be used in determining compliance with an applicable criteria for a substance shall be collected after:

(A) All remedial actions conducted to achieve compliance with pollutant mobility criteria and the applicable groundwater criteria for such substance have been concluded, other than natural attenuation of a groundwater plume or the recording of an EUR;

(B) The aquifer is no longer subject to the transient effects on hydraulic head attributable to withdrawal from or injection to groundwater for the purpose of remediation, or other effects due to site redevelopment or remediation;

(C) Any changes to the geochemistry induced by remedial actions or monitoring well construction methods that might influence the concentration of such substance have stabilized and equilibrium geochemical conditions are established; and

(D) The groundwater plume is a diminishing state groundwater plume.

(3) Determining Compliance with Groundwater Criteria

With the exception of monitoring conducted in accordance with subparagraph (B)(ii) or (C)(ii) of this subdivision, when determining compliance with applicable groundwater criteria for substances, a minimum of four (4) sampling events shall be performed which reflect seasonal variability on a quarterly basis, provided that all sampling events used to demonstrate compliance are performed within two (2) years prior to the most current sampling event used to determine compliance, and shall comply with this subdivision.

(A) Determining Compliance with Groundwater Protection Criteria or the Background Concentration

Compliance with the groundwater protection criteria or the background concentration for each substance in groundwater is achieved when sampling locations used for compliance are representative of the subject groundwater plume, and either:

(i) All laboratory analytical results for such substance at all sampling locations are equal to or less than the groundwater protection criteria or the background concentration, whichever is applicable; or

(ii) The ninety-five percent upper confidence level of the arithmetic mean of a statistically representative sampling data set consisting of all laboratory analytical results for such substance for no less than twelve consecutive monthly samples, calculated individually for each sampling location, is equal to or less than the groundwater protection criteria or the background concentration, whichever is applicable.

(B) Determining Compliance with Surface Water Protection Criteria or Water Quality Criteria

Compliance with the surface water protection criteria for each substance in groundwater is achieved when sampling locations are representative of the subject groundwater plume, and either

(i) For sample locations in that portion of such groundwater plume which is upgradient of the area at which such groundwater discharges to the receiving surface water body:

(I) All laboratory analytical results for such substance are less than or equal to the surface water protection criteria or, if applicable, the water quality criteria; or

(II) The ninety-five (95) percent upper confidence level of the arithmetic mean of a statistically representative sampling data set consisting of all laboratory analytical results for such substance for no less than twelve (12) consecutive monthly samples, calculated individually for each sampling location, is equal to or less than the surface water protection criteria or, if applicable, the water quality criteria; or

(ii) The ninety-five (95) percent upper confidence level of the arithmetic mean of a statistically representative sampling data set consisting of all laboratory analytical results for such substance in the entire groundwater plume, collected to reflect seasonal variability on a quarterly basis, is equal to or less than the surface water protection criteria or, if applicable, the water quality criteria.

(i) Compliance with volatilization criteria for each substance in groundwater is achieved when the sampling is representative of the subject groundwater plume and all laboratory analytical results for such substance are equal to or less than the applicable volatilization criteria for groundwater.

(ii) Compliance with volatilization criteria for each substance in soil vapor is achieved when the sampling is representative of the subject soil vapor, including during the heating and cooling seasons, and the results of all laboratory analytical results for such substance are equal to or less than the applicable volatilization criteria for soil vapor.

(D) Alternative Methods to Determine Compliance with the Groundwater Criteria

The commissioner may approve or deny in writing a request for an alternative to the methods prescribed in this subdivision to determine compliance with an applicable groundwater criteria. Such proposed alternative methods may be based upon emerging technologies and approaches for which guidance, a standard, or an industrial code has been published by a regulatory agency, governmental advisory group, or other recognized professional organization. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include any other information that the commissioner deems necessary to evaluate such request. Any approval by the commissioner may specify conditions necessary to protect human health and the environment.

(4) Upgradient Groundwater Plume

(A) In the circumstance where it is demonstrated that substances in a groundwater plume from an upgradient parcel are migrating onto the subject downgradient parcel, the concentrations of such substances in the groundwater plume at the downgradient parcel may be equal to or less than the concentrations of such substances found in the groundwater plume at the boundary between such parcels, provided that:

(i) Soil on the downgradient parcel has been remediated and compliance with the standards for soil in section 22a-133k-2 of the RSRs has been achieved;

(ii) At the downgradient parcel, all exposure pathways to drinking water supply wells and from volatilization of volatile organic substances into buildings have been eliminated or mitigated to the extent necessary to protect human health; and

(iii) Such substances are not already present in a groundwater plume at the downgradient parcel.

(B) In the circumstance where it is demonstrated that substances in a groundwater plume from an upgradient parcel are migrating onto a downgradient parcel and such substances have co-mingled with the same substances found in a groundwater plume at the downgradient parcel, in addition to the requirements in subparagraph (A) of this subdivision:

(i) The co-mingled groundwater plume on the downgradient parcel may be equal to or less than the concentrations of such substances found in the groundwater plume at the boundary between such parcels; and

(ii) All exposure pathways to drinking water supply wells and from volatilization of volatile organic substances into buildings at all parcels impacted by the groundwater plume emanating from the downgradient parcel have been eliminated or mitigated to the extent necessary to protect human health.

(C) Notice of the use of this provision as part of remediation shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs and shall demonstrate compliance with this subdivision.

(D) This section does not apply to substances in a groundwater plume on a downgradient parcel where such substances are not migrating onto such parcel from an upgradient parcel or such substances are different than those migrating onto such parcel.

(i) Additional Polluting Substances

(1) Groundwater Protection Criteria for Additional Polluting Substances

(A) Any substance in groundwater for which a groundwater protection criterion is not specified in Appendix C of the RSRs, shall be remediated to the background concentration or to criteria obtained pursuant to this subdivision. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A proposed risk-based groundwater protection criteria for each substance calculated in accordance with Appendix G of the RSRs;

(ii) The laboratory reporting limit for each substance;

(iii) A description of the organoleptic properties of each substance; and

(iv) Any information about the health effects such substance may cause due to exposure not accounted for in the proposed risk-based groundwater protection criteria.

(B) The commissioner may approve or deny in writing a request made under subparagraph (A) of this subdivision. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the requirements of this subdivision have been satisfied and that the proposed groundwater protection criteria will be protective of human health and the environment.

(C) Unless prohibited in writing by the commissioner, criteria approved by the commissioner pursuant to subparagraph (B) of this subdivision, may be the subject of a request for alternative criteria under subsection (d)(2) of this section.

(2) Surface Water Protection Criteria for Additional Polluting Substances

(A) Any substance in groundwater for which a surface water protection criterion is not specified in Appendix D of the RSRs or for which there are no water quality criteria, shall be remediated to the background concentration or to criteria obtained pursuant to this subdivision. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A proposed risk-based surface water protection criteria for each substance calculated in accordance with Appendix G of the RSRs;

(ii) The laboratory reporting limit for each substance;

(iii) A description of the bioaccumulative properties of each substance; and

(iv) Any information about the ecological effects each substance may cause due to exposure not accounted for in the proposed risk-based surface water protection criteria.

(B) The commissioner may approve or deny in writing a request made under subparagraph (A) of this subdivision. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the requirements of this subdivision have been satisfied and that the proposed surface water protection criteria will be protective of human health and the environment.

(3) Volatilization Criteria for Additional Polluting Substances

(A) Any substance in groundwater for which a volatilization criterion is not specified in Appendix E or Appendix F of the RSRs, shall be remediated to the background concentration or to criteria obtained pursuant to this subdivision. Such request may include target indoor air concentrations and volatilization criteria to apply to such substances in groundwater or soil vapor. A request under this subdivision shall be submitted to the commissioner in accordance with section 22a-133k-1(g) of the RSRs, and shall also include:

(i) A risk-based target indoor air concentration or volatilization criteria for each substance calculated in accordance with Appendix G of the RSRs;

(ii) The laboratory reporting limit for each substance;

(iii) A description of the odor threshold of each substance; and

(iv) Any information about the health effects each substance may cause due to exposure not accounted for in the proposed risk-based volatilization criteria.

(B) Such volatilization criteria shall ensure that such target indoor air concentrations will not be exceeded above the polluted groundwater.

(C) The commissioner may approve or deny in writing a request made under subparagraph (A) of this subdivision. No request shall be approved unless it is demonstrated to the commissioner’s satisfaction that the requirements of this subdivision have been satisfied and that the proposed volatilization criteria will be protective of human health and the environment.

(D) Unless prohibited in writing by the commissioner, criteria approved by the commissioner pursuant to subparagraph (C) of this subdivision, may be the subject of a request for alternative criteria under subsection (c)(4) of this section.

(j) Additional Remediation of Groundwater

Nothing in the RSRs shall preclude the commissioner from taking any action necessary to prevent or abate pollution, or to prevent or abate any threat to human health or the environment. If the presence of any substance impairs the aesthetic quality of any groundwater which is or can reasonably be expected to be a source of water for drinking or other uses, additional remediation shall be conducted in order to reduce the concentration of such substance to a concentration appropriate for such use.

Appendix A to the RSRs

Direct Exposure Criteria for Soil

Substance	Residential DEC in mg/kg(ppm)	Industrial/Commercial DEC in mg/kg(ppm)
Volatile Organic Substances
Acetone	500	1,000
Acrylonitrile	1.1	11
Benzene	21	200
Bromoform	78	720
2-Butanone (MEK)	500	1,000
Carbon tetrachloride	4.7	44
Chlorobenzene	500	1,000
Chloroform	100	940
Dibromochloromethane	7.3	68
1,2-Dichlorobenzene	500	1,000
1,3-Dichlorobenzene	500	1,000
1,4-Dichlorobenzene	26	240
1,1-Dichloroethane	500	1,000
1,2-Dichloroethane	6.7	63
1,1-Dichloroethylene	1	9.5
cis-1,2-Dichloroethylene	500	1,000
trans-1,2-Dichloroethylene	500	1,000
1,2-Dichloropropane	9	84
1,3-Dichloropropene	3.4	32
Ethylbenzene	500	1,000
Ethylene dibromide (EDB)	0.007	0.067
Methyl-tert-butyl-ether	500	1,000
Methyl isobutyl ketone	500	1,000
Methylene chloride	82	760
Styrene	500	1,000
1,1,1,2-Tetrachloroethane	24	220
1,1,2,2-Tetrachloroethane	3.1	29
Tetrachloroethylene	12	110
Toluene	500	1,000
1,1,1-Trichloroethane	500	1,000
1,1,2-Trichloroethane	11	100
Trichloroethylene	56	520
Vinyl chloride	0.32	3
Xylenes	500	1,000
Semi-volatile Organic Substances
Acenaphthylene	1,000	2,500
Anthracene	1,000	2,500
Benzo(a)anthracene	1	7.8
Benzo(b)fluoranthene	1	7.8
Benzo(k)fluoranthene	8.4	78
Benzo(a)pyrene	1	1
Bis(2-chloroethyl)ether	1	5.2
Bis(2-chloroisopropyl) ether	8.8	82
Bis(2-ethyl hexyl) phthalate	44	410
Butyl benzl phthalate	1,000	2,500
2-chlorophenol	340	2,500
Di-n-butyl phthalate	1,000	2,500
Di-n-octyl phthalate	1,000	2,500
2,4-Dichlorophenol	200	2,500
Fluoranthene	1,000	2,500
Fluorene	1,000	2,500
Hexachloroethane	44	410
Hexachlorobenzene	1	3.6
Naphthalene	1,000	2,500
Pentachlorophenol	5.1	48
Phenanthrene	1,000	2,500
Phenol	1,000	2,500
Pyrene	1,000	2,500
Inorganic Substances
Antimony	27	8,200
Arsenic	10	10
Barium	4,700	140,000
Beryllium	2	2
Cadmium	34	1,000
Chromium, trivalent	3,900	51,000
Chromium, hexavalent	100	100
Copper	2,500	76,000
Cyanide	1,400	41,000
Lead	400	1,000
Mercury	20	610
Nickel	1,400	7,500
Selenium	340	10,000
Silver	340	10,000
Thallium	5.4	160
Vanadium	470	14,000
Zinc	20,000	610,000
Pesticides, PCBs and Extractable Total Petroleum Hydrocarbons
Alachlor	7.7	72
Aldicarb	14	410
Atrazine	2.8	26
Chlordane	0.49	2.2
Dieldrin	0.038	0.36
Endrin	20	610
2-4 D	680	20,000
Heptachlor epoxide	0.067	0.63
Heptachlor	0.14	1.3
Lindane	20	610
Methoxychlor	340	10,000
Toxaphene	0.56	5.2
PCBs (The use of the Industrial/Commercial DEC requires the parcel to be used pursuant to section 22a-133k-2(b)(4), and in accordance with title 40 CFR Part 761)	1	10
TPH- Total Petroleum Hydrocarbons by EPA Method 418.1 (This method shall not be used for the analysis of samples collected after June 30, 2009)	500	2,500
Extractable Total Petroleum Hydrocarbons by ETPH Analysis	500	2,500

Appendix B to the RSRs

Pollutant Mobility Criteria for Soil

Substance	GA Area PMC in mg/kg (ppm)	GB Area PMC in mg/kg (ppm)
Volatile Organic Substances
Acetone	14	140
Acrylonitrile	0.01	0.1
Benzene	0.02	0.2
Bromoform	0.08	0.8
2-Butanone (MEK)	8	80
Carbon tetrachloride	0.1	1
Chlorobenzene	2	20
Chloroform	0.12	1.2
Dibromochloromethane	0.01	0.1
1,2-Dichlorobenzene	3.1	3.1
1,3-Dichlorobenzene	12	120
1,4-Dichlorobenzene	1.5	15
1,1-Dichloroethane	1.4	14
1,2-Dichloroethane	0.02	0.2
1,1-Dichloroethylene	0.14	1.4
cis-1,2-Dichloroethylene	1.4	14
trans-1,2-Dichloroethylene	2	20
1,2-Dichloropropane	0.1	1.0
1,3-Dichloropropene	0.01	0.1
Ethyl benzene	10.1	10.1
Ethylene dibromide (EDB)	0.01	0.1
Methyl-tert-butyl-ether	2	20
Methyl isobutyl ketone	7	14
Methylene chloride	0.1	1.0
Styrene	2	20
1,1,1,2-Tetrachloroethane	0.02	0.2
1,1,2,2-Tetrachloroethane	0.01	0.1
Tetrachloroethylene	0.1	1
Toluene	20	67
1,1,1-Trichloroethane	4	40
1,1,2-Trichloroethane	0.1	1
Trichloroethylene	0.1	1.0
Vinyl chloride	0.04	0.40
Xylenes	19.5	19.5
Semi-volatile Organic Substances
Acenaphthylene	8.4	84
Anthracene	40	400
Benzo(a)anthracene	1	1
Benzo(b)fluoranthene	1	1
Benzo(k)fluoranthene	1	1
Benzo(a)pyrene	1	1
Bis(2-chloroethyl)ether	1	2.4
Bis(2-chloroisopropyl)ether	1	2.4
Bis(2-ethyl hexyl)phthalate	1	11
Butyl benzl phthalate	20	200
2-chlorophenol	1	7.2
Di-n-butyl phthalate	14	140
Di-n-octyl phthalate	2	20
2,4-Dichlorophenol	1	4
Fluoranthene	5.6	56
Fluorene	5.6	56
Hexachloroethane	1	1
Hexachlorobenzene	1	1
Naphthalene	5.6	56
Pentachlorophenol	1	1
Phenanthrene	4	40
Phenol	80	800
Pyrene	4	40
Pesticides and Extractable Total Petroleum Hydrocarbons
Alachlor	0.230	0.4
Aldicarb	1	1
Atrazine	0.2	0.2
Chlordane	0.066	0.066
Dieldrin	0.007	0.007
2-4 D	1.4	14
Heptachlor epoxide	0.02	0.02
Heptachlor	0.013	0.013
Lindane	0.02	0.04
Methoxychlor	0.8	8
Simazine	0.8	8
Toxaphene	0.33	0.6
Total Petroleum Hydrocarbon by EPA Method 418.1 (This method shall not be used for the analysis of samples collected after June 30, 2009)	500	2,500
Extractable Total Petroleum Hydrocarbons by ETPH Analysis	500	2,500

Substances	GA Area PMC by TCLP or by SPLP in mg/L (ppm)	GB Area PMC by TCLP or by SPLP in mg/L (ppm)
Inorganic Substances and PCBs
Antimony	0.006	0.06
Arsenic	0.05	0.5
Barium	1	10.0
Beryllium	0.004	0.04
Cadmium	0.005	0.05
Chromium, total	0.05	0.5
Copper	1.3	13
Cyanide (by SPLP only)	0.2	2
Lead	0.015	0.15
Mercury	0.002	0.02
Nickel	0.1	1.0
Selenium	0.05	0.5
Silver	0.036	0.36
Thallium	0.005	0.05
Vanadium	0.05	0.50
Zinc	5	50
PCBs	0.0005	0.005

Appendix C to the RSRs

Groundwater Protection Criteria

Substance	GWPC in µg/L (ppb)
Volatile Organic Substances
Acetone	700
Acrylonitrile	0.5
Benzene	1
Bromoform	4
2-Butanone (MEK)	400
Carbon tetrachloride	5
Chlorobenzene	100
Chloroform	6
Dibromochloromethane	0.5
1,2-Dichlorobenzene	600
1,3-Dichlorobenzene	600
1,4-Dichlorobenzene	75
1,1-Dichloroethane	70
1,2-Dichloroethane	1
1,1-Dichloroethylene	7
cis-1,2-Dichloroethylene	70
trans-1,2-Dichloroethylene	100
1,2-Dichloropropane	5
1,3-Dichloropropene	0.5
Ethyl benzene	700
Ethylene dibromide (EDB)	0.05
Methyl-tert-butyl-ether	100
Methyl isobutyl ketone	350
Methylene chloride	5
Styrene	100
1,1,1,2-Tetrachloroethane	1
1,1,2,2-Tetrachloroethane	0.5
Tetrachloroethylene	5
Toluene	1,000
1,1,1-Trichloroethane	200
1,1,2-Trichloroethane	5
Trichloroethylene	5
Vinyl chloride	2
Xylenes	530
Semi-volatile Organic Substances
Acenaphthylene	420
Anthracene	2,000
Benzo(a)anthracene	0.06
Benzo(b)fluoranthene	0.08
Benzo(k)fluoranthene	0.5
Benzo(a)pyrene	0.2
Bis(2-chloroethyl)ether	12
Bis(2-chloroisopropyl)ether	12
Bis(2-ethyl hexyl)phthalate	2
Butyl benzl phthalate	1,000
2-chlorophenol	36
Di-n-butyl phthalate	700
Di-n-octyl phthalate	100
2,4-Dichlorophenol	20
Fluoranthene	280
Fluorene	280
Hexachloroethane	3
Hexachlorobenzene	1
Naphthalene	280
Pentachlorophenol	1
Phenanthrene	200
Phenol	4,000
Pyrene	200
Inorganic Substances
Antimony	6
Arsenic	50
Asbestos (in mfl)	7
Barium	1,000
Beryllium	4
Cadmium	5
Chromium (total)	50
Copper	1,300
Cyanide	200
Lead	15
Mercury	2
Nickel	100
Selenium	50
Silver	36
Thallium	5
Vanadium	50
Zinc	5,000
Pesticides, PCBs and Extractable Total Petroleum Hydrocarbons
Alachlor	2
Aldicarb	3
Atrazine	3
Chlordane	0.3
Dieldrin	0.002
2-4 D	70
Heptachlor epoxide	0.2
Heptachlor	0.4
Lindane	0.2
Methoxychlor	40
Simazine	4
Toxaphene	3
PCB’s	0.5
Total Petroleum Hydrocarbon by EPA Method 418.1 (This method shall not be used for the analysis of samples collected after June 30, 2009)	500
Extractable Total Petroleum Hydrocarbons by ETPH Analysis	250

Appendix D to the RSRs

Surface Water Protection Criteria for Substances in Groundwater

Substance	SWPC in µg/L(ppb)
Volatile Organic Substances
Acrylonitrile	20
Benzene	710
Bromoform	10,800
Carbon tetrachloride	132
Chlorobenzene	420,000
Chloroform	14,100
Dibromochloromethane	1,020
1,2-Dichlorobenzene	170,000
1,3-Dichlorobenzene	26,000
1,4-Dichlorobenzene	26,000
1,2-Dichloroethane	2,970
1,1-Dichloroethylene	96
1,3-Dichloropropene	34,000
Ethylbenzene	580,000
Methylene chloride	48,000
1,1,2,2-Tetrachloroethane	110
Tetrachloroethylene	88
Toluene	4,000,000
1,1,1-Trichloroethane	62,000
1,1,2-Trichloroethane	1,260
Trichloroethylene	2,340
Vinyl chloride	15,750
Semi-volatile Organic Substances
Acenaphthylene	0.3
Anthracene	1,100,000
Benzo(a)anthracene	0.3
Benzo(b)fluoranthene	0.3
Benzo(k)fluoranthene	0.3
Benzo(a)pyrene	0.3
Bis(2-chloroethyl) ether	42
Bis(2-chloroisopropyl) ether	3,400,000
Bis(2-ethyl hexyl)phthalate	59
Di-n-butyl phthalate	120,000
2,4-Dichlorophenol	15,800
Fluoranthene	3,700
Fluorene	140,000
Hexachloroethane	89
Hexachlorobenzene	0.077
Phenanthrene	14
Phenol	9,200,0000
Pyrene	110,000
Inorganic Substances
Antimony	86,000
Arsenic	4
Asbestos (in mfl)	7
Beryllium	4
Cadmium	6
Chromium, trivalent	1,200
Chromium, hexavalent	110
Copper	48
Cyanide	52
Lead	13
Mercury	0.4
Nickel	880
Selenium	50
Silver	12
Thallium	63
Zinc	123
Pesticides and PCBs
Chlordane	0.3
Dieldrin	0.1
Endrin	0.1
Heptachlor epoxide	0.05
Heptachlor	0.05
Toxaphene	1
PCBs	0.5

Appendix E to the RSRs

Volatilization Criteria for Groundwater

Volatile Substance	Residential Volatilization Criteria for Groundwater in µg/L (ppb)	Industrial/Commercial Volatilization Criteria for Groundwater in µg/L (ppb)
Acetone	50,000	50,000
Benzene	215	530
Bromoform	75	2,300
2-Butanone (MEK)	50,000	50,000
Carbon Tetrachloride	5.3	14
Chlorobenzene	1,800	23,000
Chloroform	26	62
1,2-Dichlorobenzene	5,100	50,000
1,3-Dichlorobenzene	4,300	50,000
1,4-Dichlorobenzene	1,400	3,400
1,1-Dichloroethane	3,000	41,000
1,2-Dichloroethane	6.5	68
1,1-Dichloroethylene	190	920
1,2-Dichloropropane	7.4	58
1,3-Dichloropropene	11	360
Ethyl benzene	50,000	50,000
Ethylene dibromide (EDB)	0.30	11
Methyl-tert-butyl-ether	50,000	50,000
Methyl isobutyl ketone	13,000	50,000
Methylene chloride	160	2,200
Styrene	3,100	42,000
1,1,1,2-Tetrachloroethane	2	64
1,1,2,2-Tetrachloroethane	1.8	54
Tetrachloroethylene	340	810
Toluene	23,500	50,000
1,1,1-Trichloroethane	650	16,000
1,1,2-Trichloroethane	220	2,900
Trichloroethylene	27	67
Vinyl chloride	1.6	52
Xylenes	21,300	50,000

Appendix F to the RSRs

Volatilization Criteria for Soil Vapor

Volatile Substance	Residential Volatilization Criteria for Soil Vapor in parts per million by volume (ppmv)	Residential Volatilization Criteria for Soil Vapor in milligrams per cubic meter (mg/m³)	Industrial/ Commercial Volatilization Criteria for Soil Vapor in parts per million by volume (ppmv)	Industrial/ Commercial Volatilization Criteria for Soil Vapor in milligrams per cubic meter (mg/m³)
Acetone	57	140	290	690
Benzene	0.78	2.5	1.4	4.6
Bromoform	0.04	0.42	0.98	10
2-Butanone (MEK)	130	376	230	690
Carbon Tetrachloride	0.06	0.38	0.12	0.75
Chlorobenzene	6.1	28	60	280
Chloroform	0.078	0.38	0.14	0.69
1,2-Dichlorobenzene	9.2	55	95	570
1,3-Dichlorobenzene	9.2	55	95	570
1,4-Dichlorobenzene	3	18	5.5	33
1,1-Dichloroethane	14	58	150	600
1,2-Dichloroethane	0.013	0.053	0.11	0.43
1,1-Dichloroethylene	1.9	7.6	7	28
1,2-Dichloropropane	0.021	0.098	0.13	0.58
1,3-Dichloropropene	0.035	0.16	0.89	4.0
Ethyl benzene	9.3	40	93	400
Ethylene dibromide (EDB)	0.0005	0.0056	0.007	0.053
Methyl-tert-butyl- ether	34	120	73	260
Methyl isobutyl ketone	6.8	28	68	280
Methylene chloride	0.65	2.3	6.8	24
Styrene	9.3	39	95	400
1,1,1,2-Tetrachloroethane	0.009	0.062	0.22	1.5
1,1,2,2-Tetrachloroethane	0.0012	0.0083	0.028	0.19
Tetrachloroethylene	0.56	3.8	1	6.9
Toluene	42	160	180	690
1,1,1-Trichloroethane	70	380	130	690
1,1,2-Trichloroethane	0.31	1.7	3.1	17
Trichloroethylene	0.14	0.76	0.26	1.4
Vinyl chloride	0.041	0.11	1	2.6
Xylenes	38	170	160	690

Appendix G to the RSRs

Equations, Terms, and Values for Calculating Release-Specific Direct Exposure Criteria, Pollutant Mobility Criteria, Groundwater Protection Criteria, Surface Water Protection Criteria, and Volatilization Criteria, for Additional Polluting Substances and Alternative Volatilization Criteria.

(1) Direct Exposure Criteria for Additional Polluting Substances

(A) Residential Direct Exposure Criteria shall be calculated using the following equations:

(i) For carcinogenic substances:

(ii) For non-carcinogenic substances:

(iii) The abbreviations in clauses (i) and (ii) of this subparagraph shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AT_c	Averaging Time – carcinogens	25,550	days
AT_adult	Averaging Time – adult non-carcinogen	8,760	days
AT_child	Averaging Time – child non-carcinogen	2,190	days
BW_adult	Body Weight – adult	70	kg
BW_child	Body Weight – child	15	kg
CF	Conversion Factor	0.000001	kg/mg
CSF	Cancer Slope Factor	Substance-specific	(mg/kg-day)^-1
RDEC_RB	Residential Risk-based Direct Exposure Criterion	calculated	mg/kg
ED_adult	Exposure Duration – adult non-carcinogen	24	years
ED_child	Exposure Duration – child non-carcinogen	6	years
EF	Exposure Frequency	365	days/year
HI	Hazard Index	1.0	unitless
IR_adult	Ingestion Rate – adult	100	mg/day
IR_child	Ingestion Rate – child	200	mg/day
RfD	Reference Dose	Substance-specific	mg/kg-day
RL	Target Cancer Risk Level	1.0E-06	unitless

(iv) If the residential Direct Exposure Criteria calculated pursuant to this subparagraph exceeds the following ceiling values, the ceiling value shall be used in lieu of the calculated value:

Volatile Organic Substances	Semi-volatile Organic Substances	Pesticides, PCBs and ETPH	Inorganic Substances	Units
500	1,000	500	50,000	mg/kg

(v) The residential direct exposure criteria may be adjusted up to the laboratory reporting limit if the commissioner determines that the calculated residential risk-based direct exposure criteria is less than the laboratory reporting limit for such substance.

(B) Industrial/commercial Direct Exposure Criteria shall be calculated using the following equations:

(i) For carcinogenic substances:

(ii) For non-carcinogenic substances:

(iii) The abbreviations in clauses (i) and (ii) of this subparagraph shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AT_c	Averaging Time – carcinogens	25,550	days
AT	Averaging Time – non-carcinogen	9,125	days
BW	Body Weight – adult	70	kg
CF	Conversion Factor	0.000001	kg/mg
CSF	Cancer Slope Factor	substance-specific	(mg/kg-day)^-1
I/CDEC_RB	Industrial/Commercial Risk-based Direct Exposure Criterion	calculated	mg/kg
ED	Exposure Duration	25	years
EF	Exposure Frequency	250	days/year
HI	Hazard Index	1.0	unitless
IR	Ingestion Rate	50	mg/day
RfD	Reference Dose	substance-specific	mg/kg-day
RL	Target Cancer Risk Level	1.0E-06	unitless

(iv) If the industrial/commercial direct exposure criteria calculated pursuant to this subparagraph exceeds the following ceiling values, the ceiling value shall be used in lieu of the calculated value:

Volatile Organic Substances	Semi-volatile Organic Substances	Pesticides, PCBs and ETPH	Inorganic Substances	Units
1,000	2,500	1,000	50,000	mg/kg

(v) The industrial/commercial direct exposure criteria may be adjusted up to the laboratory reporting limit if the commissioner determines that the calculated industrial/commercial risk-based direct exposure criteria is less than the laboratory reporting limit for such substance.

(2) Pollutant Mobility Criteria for Additional Polluting Substances

(A) Pollutant Mobility Criteria for inorganic substances shall be calculated using the following equations:

(i) For GA area groundwater classification:

(ii) For GB area groundwater classification:

(B) Pollutant Mobility Criteria for organic substances shall be calculated using the following equations:

(i) For GA area groundwater classification:

(ii) For GB area groundwater classification:

(C) The abbreviations in subparagraphs (A) and (B) of this subdivision shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AAF	Analytical Adjustment Factors	20	unitless
CF	Conversion Factor	0.001	mg/µg
DF	Dilution Factor	10	unitless
GWPC	Groundwater Protection Criteria	substance-specific	µg/L
PMC	Pollutant Mobility Criteria	calculated	mg/kg or mg/L

(3) Groundwater Protection Criteria for Additional Polluting Substances

(A) Groundwater Protection Criteria shall be calculated for carcinogenic substances using the following equation:

(B) Groundwater Protection Criteria shall be calculated for non-carcinogenic substances using the following equation:

(C) The abbreviations in subparagraphs (A) and (B) of this subdivision shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AT	Averaging Time	25,550	days
BW	Body Weight	70	kg
CSF	Cancer Slope Factor	substance-specific	(mg/kg-day)^-1
CF	Conversion Factor	0.001	mg/µg
ED	Exposure Duration	70	years
EF	Exposure Frequency	365	days/year
GWPC	Risk-based Groundwater Protection Criterion	calculated	µg/L
HI	Hazard Index	1.0	unitless
IR	Ingestion Rate	2	L/day
RfD	Reference Dose	substance-specific	mg/kg-day
RL	Target Cancer Risk Level	1.0E-06	unitless
SA	Source Allocation	0.2	unitless

(D) If the Groundwater Protection Criteria calculated pursuant to subparagraph (A) or (B) of this subdivision exceeds the following ceiling values, the ceiling value shall be used in lieu of the calculated value:

Volatile Organic Substances	Semi-volatile Organic Substances	Pesticides, PCBs, and ETPH	Inorganic Substances	Units
1,000	1,000	1,000	1,000	µg/L

(E) The groundwater protection criteria may be adjusted up to the laboratory reporting limit if the commissioner determines that the calculated risk-based groundwater protection criteria is less than the laboratory reporting limit for such substance.

(F) The groundwater protection criteria may be adjusted down to the organoleptic threshold if the commissioner determines that the calculated risk-based groundwater protection criteria is higher than the organoleptic threshold for such substance.

(4) Surface Water Protection Criteria for Additional Polluting Substances

(A) Determining Water Quality Criteria

For substances that have no water quality criteria in the water quality standards, such criteria shall be determined using EPA’s national recommended water quality criteria and, if no such criteria are available, then by using the following:

(i) Determining the Water Quality Criteria for Chronic Aquatic Life

(I) In accordance with title 40 CFR 132 Appendix A (Great Lakes Water Quality Initiative Methodologies for Development of Aquatic Life Criteria and Values);

(II) Using the Tier 1 protocols for calculating a Criterion Continuous Concentration; or

(III) If insufficient information is available to use the Tier 1 Criterion Continuous Concentration procedure, using the Tier 2 protocols for calculating a Secondary Continuous Concentration.

(ii) Calculating the Water Quality Criteria for Human Health for Fish Consumption:

(I) For carcinogenic substances:

(II) For non-carcinogenic substances:

(III) The abbreviations in subclauses (I) and (II) of this clause shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
BAF	Bioaccumulation Factor	substance-specific	unitless
BW	Body Weight	70	kg
CF	Conversion Factor	1,000	µg/mg
CSF	Cancer Slope Factor	substance-specific	(mg/kg-day)^-1
FC	Fish Consumption Rate	0.0175	kg/d
RfD	Reference Dose	substance-specific	mg/kg-day
RL	Risk Level	1.00E-06	unitless
WQC	Water Quality Criteria	substance-specific	µg/L
RSC	Relative Source Contribution	0.2	unitless

(B) Calculating the Surface Water Protection Criteria

The risk-based surface water protection criteria shall be calculated, for the lower of aquatic life or human health water quality criteria:

(i) Water quality criteria for freshwater chronic aquatic life protection as determined using subparagraph (A) of this subdivision, multiplied by ten (10); or

(ii) Water quality criteria for human health for fish consumption calculated using subparagraph (A) of this subdivision, multiplied by the applicable flow factor multiplied by ten (10), using the following values:

Flow Factor	Substance Risk Level
1	For known human carcinogens or substances which may bioaccumulate BCF> 100
2	For non-carcinogenic substances
3	For carcinogenic substances

(C) If the Surface Water Protection Criteria calculated pursuant to subparagraph (B) of this subdivision exceeds the following ceiling values, the ceiling value shall be used in lieu of the calculated value:

Volatile Substances	Semi-volatile Organic Substances	Pesticides, PCBs and ETPH	Inorganic Substances	Units
10,000	10,000	10,000	10,000	µg/L

(D) The surface water protection criteria may be adjusted up to the laboratory reporting limit if the commissioner determines that the calculated risk-based surface water protection criteria is less than the laboratory reporting limit for such substance.

(5) Volatilization Criteria for Additional Polluting Substances

(A) Residential Target Indoor Air Concentrations shall be calculated using the following equations:

(i) For carcinogenic substances:

(ii) For non-carcinogenic substances:

(iii) The abbreviations in this subparagraph shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AT	Averaging Time – non-carcinogen	10,950	days
AT_c	Averaging Time – carcinogen	25,550	days
BW	Body Weight	70	kg
CexpF	Children’s Exposure Factor	2	unitless
CF	Conversion Factor	1,000	µg/mg
CsensF	Children’s Sensitivity Factor CsensF = 1 for non-carcinogens and non-mutagenic carcinogens. CsensF = 2 for mutagenic carcinogens	substance-specific	unitless
CSF_i	Cancer Slope Factor – Inhalation	substance-specific	(mg/kg-day)^-1
ED	Exposure Duration	30	years
EF	Exposure Frequency	350	days/year
HQ	Hazard Quotient	1	unitless
IR_air	Inhalation Rate – air	20	m³/day
RfD_i	Reference Dose – inhalation	substance-specific	mg/m³
RL	Risk Level	1.00E-06	unitless
TAC	Target Indoor Air Concentration	substance-specific	µg/m³

(iv) If the residential Target Indoor Air Concentration calculated pursuant to clause (i) or (ii) of this subparagraph exceeds a ceiling value of 500 µg/m³, the ceiling value shall be used in lieu of the calculated value.

(B) Industrial/Commercial Target Indoor Air Concentrations shall be calculated using the following equations:

(i) For carcinogenic substances:

(ii) For non-carcinogenic substances:

(iii) The abbreviations used in this subparagraph shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
AT	Averaging Time – non-carcinogen	9,125	days
AT_c	Averaging Time – carcinogen	25,550	days
BW	Body Weight	70	kg
CF	Conversion Factor	1,000	µg/mg
CSF_i	Cancer Slope Factor – inhalation	substance-specific	(mg/kg-day)^-1
ED	Exposure Duration	25	years
EF	Exposure Frequency	250	days/year
HQ	Hazard Quotient	1	unitless
IR_air	Inhalation Rate – air	10	m³/day
RfD_i	Reference Dose – inhalation	substance-specific	mg/m³
RL	Risk Level	1.00E-06	unitless
TAC	Target Indoor Air Concentration	substance-specific	µg/m³

(iv) If the industrial/commercial Target Indoor Air Concentration calculated pursuant to clause (i) or (ii) of this subparagraph exceeds a ceiling value of five hundred (500) µg/m³, the ceiling value shall be used in lieu of the calculated value.

(i) For Volatilization Criteria for Groundwater:

(ii) If the groundwater volatilization criteria calculated pursuant to clause (i) of this subparagraph exceeds a ceiling value of fifty thousand (50,000) µg/L, the ceiling value shall be used in lieu of the calculated value.

(iii) For Volatilization Criteria for Soil Vapor:

(iv) The attenuation factor for diffusion and advection (α) shall be calculated using the following equations:

(v) The abbreviations used in this subparagraph shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
α	Attenuation Factor for Diffusion and Advection	calculated	unitless
A_B	Surface Area of the Enclosed Space in Contact with Soil	site-specific	m²
CF	Conversion Factor	1,000	L/m³ or µg/mg
D^air	Molecular Diffusion Coefficient in Air	substance-specific	m²/d
D^eff_T	Total Effective Diffusion	calculated	cm²/s
D^eff_crack	Effective Diffusion Through Foundation Cracks	calculated	cm²/s
D^eff_cap	Effective Diffusion Through Capillary Fringe	calculated	cm²/s
D^eff_vadose	Effective Diffusion Through Vadose Zone	calculated	cm²/s
D^water	Molecular Diffusion Coefficient in Water	substance-specific	m²/d
D^water/D^air	Ratio of Molecular Diffusion in Water to Air = D^water/D^air	calculated	unitless
E_B	Enclosed Space Air Exchange Rate	site-specific	1/day
GWVC	Groundwater Volatilization Criteria	calculated	µg/L
H	Henry’s Law Constant	substance-specific	unitless
k	Soil Vapor Permeability	site-specific	cm²
L_T	Depth from foundation to source	site-specific	m
L_cap	Thickness of Capillary Fringe	site-specific	m
L_crack	Foundation Thickness	site-specific	m
L_vadose	Thickness of Vadose Zone = L_T - L_cap	calculated	m
MV	Molar Volume (at standard conditions)	24.45	L
MW	Molecular Weight	substance-specific	g/mol
η	Fraction of Enclosed Space Area Open for Vapor Intrusion	site-specific	m²/d
θ_m-cap	Volumetric Moisture Content in Cracks in Capillary Fringe	site-specific	unitless
θ_T-cap	Total Porosity in Capillary Fringe	site-specific	unitless
θ_V-cap	Volumetric Vapor Constant in Capillary Fringe = θ_T-cap -^θ_m-cap	calculated	unitless
θ_m-crack	Volumetric Moisture Content in Cracks	site-specific	unitless
θ_T-crack	Total Porosity in Crack	site-specific	unitless
θ_V-crack	Volumetric Vapor Content in Cracks = θ_T-crack - θ_m-crack	calculated	unitless
θ_m-vadose	Volumetric Moisture Content in Vadose Zone	site-specific	unitless
θ_T-vadose	Total Porosity in Vadose Zone	site-specific	unitless
θ_V-vadose	Volumetric Vapor Content in Vadose Zone = θ_T-vadose-^θ_m-vadose	calculated	unitless
ΔP	Indoor-Outdoor Air Pressure Difference	site-specific	g/ms²
Q_B	Enclosed Space Volumetric Air Flow Rate = V_BE_B	calculated	m³/d
Q_soil	Pressure Driven Soil Gas Flow Rate from the subsurface into the enclosed space = (2πkΔPX_crack)/[µln(2Z_crack/R_crack)]	calculated	m³/d
Q_soil/Q_B	Ratio of Soil Gas Intrusion Rate to Building Ventilation Rate = Q_soil/Q_B	calculated	unitless
R_crack	Effective Crack Radius or Width = ηA_B/X_crack	calculated	m
SVVC	Soil Vapor Volatilization Criteria	calculated	mg/m³
TAC	Target Indoor Air Concentration calculated using subparagraph (A) or (B), as applicable	substance-specific	µg/m³
µ	Viscosity of Air	substance-specific	g/ms
VB	Enclosed Space Volume	site-specific	m³
V_B/V_A	Ratio of Enclosed Space Volume to Exposed Surface Area = V_B/V_A	calculated	m
X_crack	Total Length of Cracks through which Soil Gas Vapors are Flowing	site-specific	m
Z_crack	Crack Opening Depth Below Grade	site-specific	m

Appendix H to the RSRs

Equations, Terms, and Values for Calculating Release-Specific Alternative Pollutant Mobility Criteria

(1) Release-Specific Pollutant Mobility Criteria shall be calculated using the following equation:

(2) The abbreviations in subdivision (1) of Appendix H of the RSRs, shall be interpreted in accordance with the following table and shall be assigned the values specified therein:

Terms	Description	Value	Units
Alt PMC	Alternative Pollutant Mobility Criteria	calculated	mg/kg
GWC	Groundwater Criteria Goal	substance-specific (lowest of groundwater criteria applicable to release area)	mg/L
DF	Dilution Factor	20 or calculated in accordance with section 22a-133k-2(c)(2)(E)(ii) of the RSRs with F_adj = 0	unitless
K_d	Distribution Coefficient for Organic Contaminants may be approximated by: K_oc*f_oc	substance-specific (see table below for inorganic substances)	L/kg
K_oc	Soil Organic Carbon-water Partition Coefficient	substance-specific (see table below for organic substances)	L/kg
f_oc	Soil Fraction of Organic Carbon	0.001 or tested for site-specific value (max value = 0.006)	kg/kg
θ_w	Water-filled Soil Porosity	0.28	L_water/L_soil
θ_a	Air-filled Soil Porosity	0.15	L_air/L_soil
H’	Henry’s Law Constant	substance-specific (see tables below)	unitless
ρ_b	Dry Soil Bulk Density	1.5	kg/L

Soil Organic Carbon-Water Partition Coefficient (K_oc) and Henry’s Law Constant (H’) Values for Organic Substances

Substance	K_oc (L/kg)	H’ (Dimensionless)
Acenaphthylene	6,800	4.51E-03
Acetone	0.575	1.75E-03
Acrylonitrile	2	4.10E-03
Alachlor	310	4.30E-07
Aldicarb	24.6	5.89E-08
Anthracene	23,500	2.67E-03
Atrazine	360	1.21E-07
Benzene	62	2.26E-01
Benzo(a)anthracene	358,000	1.37E-04
Benzo(a)pyrene	969,000	4.63E-05
Benzo(b)fluoranthene	1,230,000	4.55E-03
Benzo(k)fluoranthene	1,230,000	3.40E-05
Bis(2-chloroethyl)ether	76	7.38E-04
Bis(2-chloroisopropyl)ether	360	3.03E-03
Bis(2-ethylhexyl)phthalate	111,000	4.18E-06
Bromoform	126	2.18E-02
2-Butanone (MEK)	10	1.12E-03
Butyl benzyl phthalate	13,700	5.17E-05
Carbon tetrachloride	152	1.20E+00
Chlordane	51,300	1.99E-03
Chlorobenzene	224	1.61E-01
Chloroform	53	1.39E-01
2-Chlorophenol	398	1.60E-02
Dibromochloromethane (Chlorodibromomethane)	63.1	3.21E-02
1,2-Dichlorobenzene (o)	379	7.95E-02
1,3-Dichlorobenzene (m)	700	1.08E-01
1,4-Dichlorobenzene (p)	616	1.12E-01
1,1-Dichloroethane	53	2.23E-01
1,2-Dichloroethane	38	4.51E-02
1,1-Dichloroethylene	65	6.11E-01
cis-1,2-Dichloroethylene	35.5	1.70E-01
trans-1,2-Dichloroethylene	38	3.80E-01
2,4-Dichlorophenol	159	1.30E-04
2,4-Dichlorophenoxyacetic acid (2,4-D)	29.6	1.45E-06
1,2-Dichloropropane	47	1.16E-01
1,3-Dichloropropene	27	1.44E-01
Dieldrin	25,500	6.19E-04
Di-n-butyl phthalate	1,570	3.85E-08
Di-n-octyl phthalate	140,000	2.74E-03
Ethylbenzene	204	1.41E-01
Ethylene dibromide (EDB)	66	2.76E-02
Fluoranthene	49,100	6.60E-04
Fluorene	7,710	2.61E-03
Heptachlor	9,530	4.47E-02
Heptachlor epoxide	83,200	3.90E-04
Hexachlorobenzene	80,000	5.41E-02
g-HCH (Lindane)	1,350	5.74E-04
Hexachloroethane	1,780	1.59E-01
Methoxychlor	80,000	6.48E-04
Methyl isobutyl ketone	65	5.33E-03
Methyl-tert-butyl-ether (MTBE)	34	2.42E-02
Methylene chloride	10	1.31E-01
Naphthalene	1,190	1.98E-02
Pentachlorobenzene	32,100	2.87E-02
Pentachlorophenol	7,960	1.00E-06
Phenanthrene	21,200	9.43E-04
Phenol	28.8	1.63E-05
Pyrene	68,000	4.51E-04
Simazine	147	3.85E-08
Styrene	912	1.07E-01
1,1,1,2-Tetrachloroethane	86	4.51E-01
1,1,2,2-Tetrachloroethane	79	1.56E-02
Tetrachloroethylene	265	8.36E-02
Toluene	140	2.74E-01
Toxaphene	95,800	2.46E-04
1,1,1-Trichloroethane	135	9.47E-01
1,1,2-Trichloroethane	75	3.73E-02
Trichloroethylene	94	3.74E-01
Vinyl chloride	18.6	1.14E+00
Xylenes	1,700	2.16E-01

Distribution Coefficient (K_d) and Henry’s Law Constant (H’) Values for Inorganic Substances

Substance	K_d (L/kg)	H’ (Dimensionless)
Antimony	45	-
Arsenic	25	-
Barium	12	-
Beryllium	26	-
Cadmium	17	-
Chromium (hexavalent or total)	31	-
Chromium (trivalent only)	1,900	-
Copper	35	-
Cyanide	9.9	-
Lead	900	-
Mercury	0.06	4.67E-01
Nickel	18	-
Silver	0.13	-
Selenium	17	-
Thallium	45	-
Vanadium	1,000	-
Zinc	18	-

Appendix I of the RSRs

Potential Alternative Groundwater Protection Map, dated December 22, 2020

The map in this Appendix is for use in accordance with section 22a-133k-3(d)(2) of the RSRs. The department shall make this map, titled “Potential Alternative Groundwater Protection Criteria Map” dated December 22, 2020, as provided in this Appendix, available on the department’s Internet website and shall also make such map available during regular business hours at the Department of Energy and Environmental Protection, Division of Water Protection and Land Reuse, 79 Elm Street, 2nd floor, Hartford, Connecticut.

If a reader is viewing said map in hard copy or on the DEEP website, any such area shaded in the color or using a similar designation is an area where a potential alternative groundwater protection area has been identified. If a reader is viewing such map on the eregs system, any area shaded in a cross-hatched pattern is an area where a potential alternative groundwater protection area has been identified.

(Effective January 30, 1996; Amended June 27, 2013; Amended February 16, 2021)