R 299.5706a 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 706a. 

          (1)  Except as provided in R 299.5532(9)  and subrules (10), (11)  and (12)  of this rule, generic groundwater cleanup criteria for the residential, commercial and industrial categories shall be the values shown in table 1 of R 299.5744.  If a generic groundwater cleanup criterion is higher than the flammability and explosivity screening level or the acute inhalation screening level shown in table 1 of R 299.5744, then the person proposing or implementing response activity shall document whether additional response activity is required to protect against those acute hazards.

          (2)  Except as provided in R 299.5532(9)  and subrules (10), (11), and (12)  of this rule, generic soil cleanup criteria for the residential and commercial i categories shall be the values shown in table 2 of R 299.5746.

          (a)  If a generic soil cleanup criterion is greater than C_sat, then  the person proposing or implementing response activity shall document whether additional response activity is required to control free-phase liquids or to protect against hazards associated with free-phase liquids that are not accounted for in development of the generic criteria.  

          (3)  Except as provided in R 299.5532(9)  and subrules (10), (11), and (12)  of this rule, generic soil cleanup criteria for the commercial II, III, IV, and industrial categories shall be the values shown in table 3 of R 299.5748.

          (4)  The generic cleanup criteria shown in R 299.5744, R 299.5746, and R 299.5748 and identified under subrule (14)  of this rule may be used and known as risk-based screening levels for corrective actions required under the part 213 of the act.

          (5)  Generic cleanup criteria under R 299.5744, R 299.5746, and R 299.5748 are based on R 299.5707 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 299.5744, R 299.5746, or R 299.5748. 

          (6)  If a hazardous substance imparts adverse aesthetic characteristics to groundwater at a concentration less than the health-based criterion for that hazardous substance, the aesthetic-based criterion derived under R 299.5709 is shown as the drinking water criterion in the table of generic cleanup criteria in R 299.5744 and designated with a footnote.

          (7)  Except as provided in section 20120a(10)  of the act and R 299.5750(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 299.5710, R 299.5712, R 299.5714, R 299.5720, R 299.5722, R 299.5724, and R 299.5726 are shown in table 4 of R 299.5752.

          (8)  Toxicological and chemical-physical data in table 4 of R 299.5752, 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 subrule (10)  or (11)  of this rule, except as provided in section 20120a(10)  of the act and R 299.5750(1)(o). 

          (9)  Except as provided in subdivision (a)  of this subrule, site-specific cleanup criteria developed under section 20120a(2)  of the act shall use the toxicological and chemical-physical data in table 4 of R 299.5752, or shall be based on the procedures allowed for under subrules (10)  and (11)  of this rule.  Site-specific assumptions may be substituted for the default assumptions specified in R 299.5710, R 299.5712, R 299.5714, R 299.5720, R 299.5722, R 299.5724, and R 299.5726, if appropriate; however, the equations presented in the pertinent rule shall be used to calculate site-specific criteria.  Non-human health based toxicological values may be modified through the development of site-specific cleanup criteria under section 20120a(2)  of the act and R 299.5716(11).

                    (a)  The following chemical-physical properties may be modified as part of a site-specific cleanup criterion developed under section 20120a(2)  of the act, if documented by the person proposing the site-specific criterion to be more appropriate for a specific facility than the generic parameter listed in table 4 of R 299.5752:

                              (i)  Relative source contribution factor for drinking water.

                              (ii)  Ingestion absorption efficiency.

                              (iii)  Dermal absorption efficiency.

                              (iv)  Relative source contribution factor for soil.

                              (v)  Soil k_oc for ionizing organic compounds.

                              (vi)  Soil-water distribution coefficients for inorganic compounds.

          (10)  For a substance that is not listed in the cleanup criteria tables in R 299.5744, R 299.5746, or R 299.5748, 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.

          (11)  For a substance that is listed in the cleanup criteria tables in R 299.5744, R 299.5746, or R 299.5748, 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 299.5752 with a footnote "ID" or "NA," the department shall use best available information to calculate a cleanup criterion for the hazardous substance. 

          (12)  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 et seq. shall become the generic residential cleanup criterion under R 299.5744, as provided in section 20120a(5)  of the act.

          (13)  If a generic cleanup criterion is developed under subrule (10)  or (11)  of this rule, or modified under subrule (12)  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 called for 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 1969 PA 306, MCL 24.201 et seq.