N.M. Admin. Code § 20.6.3.10

Current through Register Vol. 35, No. 23, December 10, 2024

Section 20.6.3.10 - PERFORMANCE STANDARD AND ASSOCIATED REQUIREMENTS

A. Activities performed pursuant to the Act shall be designed to collect, develop, and evaluate sufficient information to support proposed conclusions regarding:

(1) the source, nature and extent, migration pathways, and environmental fate and transport of contaminants in all environmental media present at the site (i.e., soil, ground water, surface water, sediment, and/or air);

(2) the risk of harm posed by the site to human health, safety, and the environment;

(3) the need to conduct remedial actions at the site to safeguard against such risks; and

(4) the remedial action selection and design, if appropriate.

B. If applicable standards are prescribed by law or regulation, voluntary remediation activities shall achieve applicable standards. Where applicable standards are not prescribed by law or regulation,voluntary remediation activities shall be performed in order to achieve a final site condition such that no contaminant will present a significant risk of harm to human health,safety, or the environment during any foreseeable period of time. Such level of cleanup shall be attained by reducing the risk from exposure to individual carcinogens or suspected carcinogens to an individual lifetime cancer risk of less than one cancer incident in 100,000 exposed persons (1 X 10 E-5); and by reducing the risk from exposure to individual noncarcinogenic contaminants to a hazard quotient of less than 1. In order to achieve this performance standard, the applicant may evaluate the risk of harm posed by the site to human health, safety, or the environment by employing one of three general methods:

(1) Method 1: Comparison of site concentrations to site-specific background concentrations; or

(2) Method 2: Comparison of site concentrations to applicable water quality standards and soil guidelines approved by the Department, including but not limited to:

(a) risk-based soil remediation guidelines developed by the department;

(b) standards for water, as listed in the most recent version of the New Mexico Water Quality Control Commission (WQCC) Regulations, 20 NMAC 6.1 [20.6.1 NMAC] and 20 NMAC 6.2 [20.6.2 NMAC], or other more stringent applicable standards, as appropriate; and

(c) other applicable standards. Where more than one applicable standard exists, the most stringent applicable standard will be applied; or

(3) Method 3: Performance of a detailed, site-specific human health and, if applicable, environmental risk assessment. Such a Method 3 evaluation will be required to employ a cumulative exposure approach. In no case shall a Method 3 evaluation propose voluntary remediation activities that are not designed to meet all applicable standards.

C. Any risk assessment conducted under this Section shall be based on reasonable and conservative assumptions about exposures and pathways, shall take into consideration exposure of sensitive subgroups to contaminants and the possibility of future changes in land use, and shall incorporate an adequate margin of safety.

D. The selection of voluntary remediation activities that will achieve a permanent solution shall be required, unless the participant demonstrates and the secretary concurs that implementation of voluntary remediation activities to achieve a permanent solution would be infeasible or impracticable.

E. An environmental risk assessment shall be required only when ecological receptors are present at or in the near vicinity of a site. Such an environmental risk assessment shall be a Method 3 site-specific assessment, and may be combined with a Method 1, 2, or 3 evaluation of human health risks.

F. The department may approve voluntary remediation activities that do not achieve residential health-based levels in all environmental media of concern only if the participant provides an affirmation of future non-residential land use, or an easement or other legal document binding on successors in interest to the site, in a form satisfactory to the department.

G. The department, in its discretion, may require an easement or other legal document binding on successors in interest to the site where voluntary remediation activities include post-completion monitoring, maintenance of engineering controls, remediation systems, or post-closure care.

N.M. Admin. Code § 20.6.3.10

7/15/99; 20.6.3.10 - Rn, 20 NMAC 6.3.I.110, Recompiled 11/27/01