Toxicity tests must be conducted by an experienced laboratory approved by the Department. The laboratory must follow the procedures described in the following USEPA methods manuals, except as modified by the Department on a case by case basis or as described in this section for the Salmonid Survival and Growth Test.
U.S. Environmental Protection Agency. 2002. Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, 5 th ed. EPA 821-R-02-012. U.S. Environmental Protection Agency, Office of Water, Washington, D.C., October 2002 (the acute method manual)
U.S. Environmental Protection Agency. 2002. Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, 4 th ed. EPA 821-R -02-013. U.S. Environmental Protection Agency, Office of Water, Washington, D.C., October 2002 (the freshwater chronic method manual)
U.S. Environmental Protection Agency. 2002. Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, 3 rd ed. EPA 821-R-02-014. U.S. Environmental Protection Agency, Office of Water, Washington, D.C., October 2002 (the marine chronic method manual)
Species - Brook Trout, Salvelinus fontinalis, or other salmonid approved by the Department.
Age - Less than six months old for the first test each year and less than twelve months for subsequent tests.
Size - The largest fish must not be greater than 150% of the smallest.
Loading Rate - < 0.5 g/l/day
Feeding rate - 5% of body weight 3 times daily (15%/day)
Temperature - 12[DEGREE] +- 1[DEGREE]C
Dissolved Oxygen - 6.5 mg/l ,aeration if needed with large bubbles (> 1 mm diameter) at a rate of <100/min
Dilution Water - Receiving water upstream of discharge (or other ambient water approved by the Department)
Dilution Series - A minimum of 5 effluent concentrations (including the instream waste concentrations bracketing acute and chronic dilutions calculated pursuant to Section D); a receiving water control; and control of known suitable water quality
Duration - Acute = 48 hours
- Chronic = 10 days minimum
Test acceptability - Acute = minimum of 90% survival in 2 days
- Chronic = minimum of 80% survival in 10 days; minimum growth of 20 mg/gm/d dry weight in controls, (individual fish weighed, dried at 100[DEGREE]C to constant weight and weighed to 3 significant figures)
06- 096 C.M.R. ch. 530, § 5