N.J. Admin. Code § 7:9C-1.7 - Ground water quality criteria

(a) Ground water quality criteria for Class I-A areas are the natural quality for each constituent. Class I-A is a non-degradation classification where natural quality is to be maintained or restored. The Department shall not approve any discharge to ground water or approve any human activity which results in a degradation of natural quality within a Class I-A classification area.

(b) Ground water quality criteria for Class I-PL are as follows:

1. Within Class I-PL (Preservation Area), ground water quality criteria shall be the natural quality for each constituent. Class I-PL (Preservation Area) is a nondegradation classification in which natural quality shall be maintained or restored. The Department shall not approve any discharge or any other activity which would result in the degradation of natural quality within a Class I-PL (Preservation Area) classification area. However, the provisions of this paragraph (b)1 shall not apply to activities that are in conformance with N.J.A.C. 7:50-6 et seq.

2. Ground water quality criteria for Class I-PL (Protection Area) shall be the background water quality. The Department shall not approve any discharge or any other activity which would result in the degradation of background water quality in the Class I-PL (Protection Area) classification area. However, the provisions of this paragraph (b)2 shall not apply to activities that are in conformance with N.J.A.C. 7:50-6 et seq.

3. The Department shall not approve any discharge to ground water within the Class I-PL classification area which results in a violation of the Surface Water Quality Standards applicable to the Pinelands National Reserve, as established in N.J.A.C. 7:9B or successor rules.

(c) Ground water quality criteria for Class II-A areas are established as follows:

1. Specific criteria for ground water quality in Class II-A areas are listed in Appendix Table l.

2. The Department may establish an interim specific criterion, pursuant to (c)3 below, for a constituent not listed in Appendix Table 1.

i. The Department shall maintain and make available to the public on its website and by request a listing of all interim specific criteria and the supplemental information used in their derivation.

ii. Interim specific criteria shall be replaced with specific criteria as soon as reasonably possible by rule.

3. The Department shall establish ground water quality criteria as follows:

i. If the Department promulgates in the Safe Drinking Water Act rules at N.J.A.C. 7:10 a maximum contaminant level (MCL) for a constituent, the health-based level used to establish the MCL shall be the specific ground water quality criterion for the constituent.

ii. For all other constituents, the Department shall develop ground water quality criteria for Class II-A ground water based upon the weight of evidence available regarding each constituent's carcinogenicity, toxicity, public welfare or organoleptic effects, as appropriate for the protection of potable water, pursuant to (c)4 below.

4. Except as provided at (c)4iv and v below, the Department shall use the equations, data sources, and conventions at (c)4i through iii below to derive specific and interim specific ground water quality criteria:

i. For constituents categorized as carcinogens, the criteria shall be derived using the following equation:

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ii. For constituents classified as non-carcinogens and for constituents classified as carcinogens for which no carcinogenic slope factor is applicable, the criterion shall be derived using the following equation:

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iii. The criteria derived by the equations in this paragraph shall be rounded to one significant figure.

iv. If the Department determines, based on constituent-specific factors and/or data, as well as applicable USEPA guidance, generally accepted scientific evidence and methodologies, and/or peer-reviewed sources of information, that use of an alternative value(s) is more suitable than a default value in the equation at (c)4i or ii above for the derivation of a particular specific or interim specific criterion, the Department shall derive the criterion using the alternative value(s). The Department will explain the basis for using any alternative value in, as applicable, the supplemental information accompanying an interim specific criterion made available to the public on the Department's website in accordance with (c)2i above, or in the Summary statement of the rulemaking for a specific criterion.

v. If the Department determines, based on constituent-specific factors and/or data, as well as applicable USEPA guidance, generally accepted scientific evidence and methodologies, and/or peer-reviewed sources of information, that use of a modified equation is more suitable than the equation at (c)4i or ii above for the derivation of a particular specific or interim specific criterion, the Department shall derive the criterion using the modified equation. The Department will explain the basis for using a modified equation in, as applicable, the supplemental information accompanying an interim specific criterion made available to the public on the Department's website in accordance with (c)2i above, or in the Summary statement of the rulemaking for a specific criterion.

5. The Department shall publish in the New Jersey Register a notice of administrative change subsequent to November 7, 2005:

i. To modify or add a new specific criterion to Appendix Table 1 when the Department promulgates in the Safe Drinking Water Act rules at N.J.A.C. 7:10 a new or revised maximum contaminant level (MCL) for a ground water constituent; or

ii. To modify a specific criterion in Appendix Table 1 where the USEPA revises the carcinogenic slope factor or reference dose data contained in the Integrated Risk Information System (IRIS) database on which a specific ground water quality criterion in Appendix Table I is based.

iii. The notice of administrative change shall identify the constituent, the basis for the administrative change and the revised criterion to be listed in Appendix Table 1.

6. For a Synthetic Organic Chemical not listed in Appendix Table 1, the applicable interim generic criterion in Appendix Table 2 shall apply until an interim specific criterion is developed or a specific criterion is promulgated in accordance with this subsection.

(d) The ground water quality criteria for Class II-B ground waters shall be the Class II-A criteria.

(e) The ground water quality criteria for Class III-A areas shall be the criteria of the most stringent classification for vertically or horizontally adjacent ground waters that are not Class III-A, unless the Department concludes (in the context of an applicable regulatory program) that there is no significant potential for the migration of ground water pollutants to that classification area. If there is significant potential for pollutant migration, the criteria shall be those of the classification area determined to be downgradient of the Class III-A area. If there is no significant potential for pollutant migration, criteria shall be determined for such Class III-A areas on a case by case basis in the context of applicable regulatory programs. In each case where there is no significant potential for pollutant migration, the criteria shall be no more stringent than necessary to ensure that there will be no:

1. Impairment of existing uses of the ground water;

2. Resulting violation of Surface Water Quality Standards;

3. Release of pollutants to the ground surface, structures or air in concentrations that pose a threat to human health;

4. Reasonable potential for a change in hydraulic gradient that could cause pollutants to migrate from the Class III-A area to any classification area other than Class III.

(f) The ground water quality criteria for Class III-B areas shall be determined on an area by area basis in response to case by case needs, in the context of applicable regulatory programs. In each case, the criteria shall be no more stringent than necessary to ensure that there will be no:

1. Impairment of existing uses of ground water;

2. Resulting violation of Surface Water Quality Standards;

3. Release of pollutants to the ground surface, structures or air in concentrations that pose a threat to human health;

4. Violation of constituent standards for downgradient classification areas to which there is a significant potential for migration of ground water pollutants.

(g) Where ground water that receives pollutants from a discharge(s) subsequently flows to surface waters, the Department shall regulate such discharges as necessary so as not to exceed the Surface Water Quality Standards applicable to that body of surface water. The discharger may request application of only the ground water quality standards by showing, to the satisfaction of the Department, and in the context of the applicable regulatory procedure, that the flow of ground water pollutants into the surface water will not cause a violation of the Surface Water Quality Standards.

(h) For constituents for which specific or interim specific criteria have been derived, the Department may evaluate potential toxicological interactions between or among constituents in ground water by the sum of the risk levels of constituents with health-based criteria that are based on carcinogenic risk, and by utilizing the hazard index approach described in the USEPA Guidelines for the Health Risk Assessment of Chemical Mixtures (51 FR 34014 (1986), and any subsequent revisions) for non-carcinogens. Additional actions and more stringent criteria may be required when either of the following conditions exists:

1. The total risk level for all carcinogens present in ground water exceeds 1 x 10[-4]; or

2. There is a Hazard Index of greater than one for noncarcinogenic effects.

(i) The Department shall regulate discharges for compliance with each specific, interim specific and generic criterion applicable to the discharge pursuant to this section.

Notes

N.J. Admin. Code § 7:9C-1.7

Amended by 50 N.J.R. 334(a), effective 1/16/2018