455H.204 Site-specific cleanup standards.
1. Procedures to establish site-specific cleanup standards shall be adopted by the commission after consideration of the joint recommendations of the department and the technical advisory committee. Site-specific cleanup standards must provide for the protection of the public health and safety and the environment.
2. Site-specific cleanup standards and appropriate response actions shall take into account all of the following provided, however, that an affected area shall not be required to be cleaned up to levels below or more restrictive than background levels, and in groundwater which is not a protected groundwater source, to a concentration level which presents an increased cancer risk of less than one in ten thousand:
a. The most appropriate exposure scenarios based on current or probable future residential, commercial, industrial, or other industry-accepted scenarios.
b. Exposure pathway characterizations including contaminant sources, transport mechanisms, and exposure pathways.
c. Affected human or environmental receptors and exposure scenarios based on current or probable projected use scenarios.
d. Risk-based corrective action assessment principles which identify risks presented to the public health and safety or the environment by each released hazardous substance in a manner that will protect the public health and safety or the environment using a tiered procedure consistent with the ASTM (American society for testing and materials) international standards applied to nonpetroleum and petroleum hazardous substances.
e. Other relevant site-specific risk-related factors such as the feasibility of available technologies, existing background levels, current and planned future uses, ecological, aesthetic, and other relevant criteria, and the applicability and availability of technological and institutional controls.
f. Cleanup shall not be required in an affected area that does not present any of the following:
(1) An increased cancer risk from a single contaminant at the point of exposure of five in one million for residential areas or one in ten thousand for nonresidential areas.
(2) An increased cancer risk from multiple contaminants or multiple routes of exposure greater than one in ten thousand.
(3) An increased noncancer health risk from a single contaminant at the point of exposure of greater than one, or greater than one-tenth for possible carcinogens.
(4) An increased noncancer risk to the same target human organ from multiple contaminants or multiple routes of exposure greater than one.
3. The concentration of a hazardous substance in an environmental medium of concern at an affected area where the site-specific standard has been selected shall not be required to meet the site-specific standard if the site-specific standard is numerically less than the background level. In such cases, the background level shall apply.
4. Any participant electing to comply with site-specific standards established by this section shall submit, as appropriate, all of the following reports and evaluations for review and approval by the department:
a. (1) A site-specific risk assessment report and a cleanup plan. The site-specific risk assessment report must include, as appropriate, all of the following:
(a) Documentation and descriptions of procedures and conclusions from the site investigation to characterize the nature, extent, direction, rate of movement, volume, and composition of hazardous substances.
(b) The concentration of hazardous substances in environmental media of concern, including summaries of sampling methodology and analytical results.
(c) A fate and transport analysis to demonstrate that no exposure pathways exist.
(2) If no exposure pathways exist, a risk assessment report and a cleanup plan are not required and no remedy is required to be proposed or completed.
b. A final report demonstrating compliance with site-specific cleanup standards has been completed in accordance with the cleanup plan.
c. This section does not preclude a participant from submitting a site-specific risk assessment report and cleanup plan at one time to the department for review.
5. Upon submission of either a site-specific risk assessment report or a cleanup plan to the department, the department shall notify the participant of any deficiencies in the report or plan in a timely manner.
6. Owners and operators of underground storage tanks other than petroleum underground storage tanks, aboveground storage tanks, and pipelines which contain or have contained petroleum shall comply with the corrective action rules issued pursuant to chapter 455B, division IV, part 8, to satisfy the requirements of this section.
97 Acts, ch 127, §11; 2002 Acts, ch 1091, §2; 2004 Acts, ch 1086, §76; 2011 Acts, ch 25, §143
Referred to in §455H.201