3. In general, whole
effluent toxicity testing will be required in the permit for discharges where
data are insufficient to demonstrate that any discharge does not or will not
contribute to ambient toxicity.
a. Tests will
be routinely run for the life of the permit on an established schedule
dependent upon on the variability of the discharge and on whether effluent
toxicity is suspected or unknown.
b. Both acute toxicity and chronic toxicity
tests may be required. Test methods found in the following sources or their
updated versions should be followed: "Methods for Measuring the Acute Toxicity
of Effluents and Receiving Waters to Freshwater and Marine Organisms," 4th
Edition, EPA/600/4-90/027F, EPA, 1993; "Short-Term Methods for Estimating the
Chronic Toxicity of Effluents And Receiving Waters To Freshwater Organisms,"
3rd Edition, EPA/600/4-91/002, EPA, 1994; and "Short-Term Methods for
Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and
Estuarine Organisms," 2nd Edition, EPA/600/4-91/003, EPA.
i. Acute toxicity tests will be considered
for "end-of-pipe" effluent. Dilution water will be receiving water collected at
a point upstream of or adequately removed from the discharge
point(s).
ii. For chronic toxicity
tests of effluent, dilution water will also be receiving stream water collected
at a point upstream of or adequately removed from the discharge point(s). In
flowing water bodies, one dilution in the series required to calculate the
no-observed-effect level (NOEL) will reflect the 7Q10 flow dilution. In some
water bodies the 7Q10 flow may not be considered adequate, and a more
appropriate low flow will be used for dilution calculations.
iii. Multiple toxicity tests using more than
one species of test organisms will normally be required. The following tests
and species are considered applicable to and representative of Louisiana
waters. Other applicable tests and test species may also be used after approval
by the department. In general, some combination of the following tests and
species will be required:
(a). for receiving
water bodies with salinities less than 2 0 (2 ppt or 2,000 ppm):
(i). 48-hour Ceriodaphnia or Daphnia pulex
acute survival;
(ii). 48- and
96-hour fathead minnow (Pimephales promelas) static renewal acute
survival;
(iii). 7-day Ceriodaphnia
chronic reproduction and survival;
(iv). 7-day fathead minnow chronic survival
and teratogenicity;
(v). 7-day
fathead minnow chronic growth and survival; and
(vi). 4-day Selenastrum chronic growth
test;
(b). for receiving
water bodies with salinities equal to or greater than 2 0 (2 ppt or 2,000 ppm):
(i). 48-hour mysid shrimp acute
survival;
(ii). 48- and 96-hour
sheepshead minnow (Cyprinodon variegatus) static renewal acute
survival;
(iii). 48-hour inland
silverside (Menidia beryllina) static renewal acute survival;
(iv). 7-day mysid shrimp survival, growth,
and fecundity;
(v). 7-day
sheepshead minnow larval survival and growth; and
(vi). 7-day inland silverside larval survival
and growth; and
(c). i f
a control test reveals upstream ambient water to be toxic, the discharger will
redo the toxicity tests using EPA- and department-approved reconstituted water
with hardness, alkalinity, pH, and conductivity comparable to the ambient
stream for dilution. The department will evaluate the toxicity data if upstream
toxicity is indicated.