Ill. Admin. Code tit. 35, § 302.563 - Determining the Tier II Lake Michigan Basin Acute Aquatic Life Toxicity Value (LMAATV)

If all eight minimum data requirements for calculating a FAV using Tier I procedures are not met, a Tier II LMAATV must be calculated for a substance as follows:

a) The lowest GMAV in the database is divided by the Secondary Acute Factor (SAF) corresponding to the number of satisfied minimum data requirements listed in the Tier I methodology (Section 302.553). To calculate a Tier II LMAATV, the database must contain, at a minimum, a GMAV for one of the following three genera in the family Daphnidae - Ceriodaphnia sp., Daphnia sp., or Simocephalus sp. The Secondary Acute Factors are:

Number of Minimum data requirements satisfied (required taxa)	Secondary Acute Factor
1	43.8
2	26.0
3	16.0
4	14.0
5	12.2
6	10.4
7	8.6

b) If dependent on a water quality characteristic, the Tier II LMAATV must be calculated according to Section 302.560.

Notes

Ill. Admin. Code tit. 35, § 302.563

Amended at 23 Ill. Reg. 11249, effective August 26, 1999

Amended at 47 Ill. Reg. 4437, effective 3/23/2023