R 299.6 Generic cleanup criteria; toxicological and chemical-physical properties; use of generic cleanup criteria as risk based screening levels; procedure for developing additional generic criteria.

Rule 6. (1) Except as provided in subrules (9), (10) and (11) of this rule, generic groundwater cleanup criteria for the residential and nonresidential categories shall be the values shown in table 1 of R 299.44. If a generic groundwater cleanup criterion is higher than the flammability and explosivity screening level shown in table 1 of R 299.44, then the person proposing or implementing response activity shall document whether additional response activity is required to protect against the acute hazard. (2) Except as provided in subrules (9), (10), and (11) of this rule, generic soil cleanup criteria for the residential category shall be the values shown in table 2 of R 299.46. If soil concentrations are greater than Csat, then the person proposing or implementing response activity shall evaluate whether additional response activity is required to control free-phase liquids or to protect against risks associated with free-phase liquids that are not accounted for in development of the generic criteria. (3) Except as provided in subrules (9), (10), and (11) of this rule, generic soil cleanup criteria for the nonresidential category shall be the values shown in table 3 of R 299.48. (4) The generic cleanup criteria shown in R 299.44, R 299.46, and R 299.48 and identified under subrule (12) of this rule may be used and known as risk-based screening levels for corrective actions required under part 213 of the act. (5) Generic cleanup criteria under R 299.44, R 299.46, and R 299.48 are based on the target detection limit or background concentration in the following cases: (a) If a calculated cleanup criterion is less than the target detection limit for that hazardous substance in a given medium, then the target detection limit is the cleanup criterion. Criteria to which this subdivision applies are designated with a footnote in the criteria tables. (b) A background concentration may be substituted for a generic cleanup criterion when the background concentration is higher than a criterion shown in R 299.44, R 299.46, or R 299.48. (6) If a hazardous substance imparts adverse aesthetic characteristics to groundwater at a concentration less than the health-based criterion for that hazardous substance, then the aesthetic-based criterion derived under R 299.9 is shown as the drinking water criterion in the table of generic cleanup criteria in R 299.44 and designated with a footnote. (7) Except as provided in section 20120a(9) of the act, R 299.49(1)(l), and R 299.49(1)(o), the toxicological and physical-chemical input values used by the department to derive generic cleanup criteria with the equations and default assumptions provided in R 299.10, R 299.14, R 299.20, R 299.22, R 299.24, and R 299.26 are shown in table 4 of R 299.50. (8) Toxicological and chemical-physical data in table 4 of R 299.50, if available, shall be used in conjunction with the equations and default assumptions that appear in these rules for the development of generic cleanup criteria under subrules (9) or (10) of this rule, except as provided in section 20120a(9) of the act, R 299.49(1)(l), and R 299.49(1)(o). (9) For a substance that is not listed in the cleanup criteria tables in R 299.44, R 299.46, or R 299.48, the department may determine if the substance is a hazardous substance using best available information about the toxicological and physical-chemical properties of that substance and use that information to develop a generic or site-specific cleanup criterion. (10) For a substance that is listed in the cleanup criteria tables in R 299.44, R 299.46, or R 299.48, if the department obtains sufficient information to support calculation of a cleanup criterion which is designated in the cleanup criteria tables or table 4 of R 299.50 with a footnote “ID” or “NA,” the department shall use best available information to calculate a cleanup criterion for the hazardous substance. (11) If a new state drinking water standard is established or a state drinking water standard is changed after the effective date of this rule, the drinking water standard in effect under section 5 of 1976 PA 399, MCL 325.1005, shall become the generic residential cleanup criterion under R 299.44, as provided in section 20120a(5) of the act. (12) If a generic cleanup criterion is developed under subrule (9) or (10) of this rule, or modified under subrule (11) of this rule, the department shall make the new toxicological and physical-chemical data and criterion available by announcing it on the department’s internet web site, and by publishing notice of the change in the department calendar, or by such other means that effectively notifies interested persons. The new criterion shall take effect when published and announced by the department as required in this rule. The new data and resulting cleanup criterion shall remain effective and be used as required under these rules until the department promulgates revised data and criteria pursuant to administrative procedures act, 1969 PA 306, MCL 24.201 to 24.328.