TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE C: WATER POLLUTION
CHAPTER I: POLLUTION CONTROL BOARD
PART 302 WATER QUALITY STANDARDS
SECTION 302.563 DETERMINING THE TIER II LAKE MICHIGAN BASIN ACUTE AQUATIC LIFE TOXICITY VALUE (LMAATV)


 

Section 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.

 

(Source:  Amended at 47 Ill. Reg. 4437, effective March 23, 2023)