NC0004308_Whole effluent toxicity test results_20180327

Division of Water Resources
March 27, 2018
MEMORANDUM
To: Corey Basinger
Water Quality Regional Operations, MRO
Through: Cindy A. Moore
Supervisor, Aquatic Toxicology Branch (ATB)
4 From: Carol Hollenkamp t
Quality Assurance Officer, Aquatic Toxicology Branch (ATB)
Subject: Whole effluent toxicity test results
Alcoa Badin Business Park Outfall 005
NPDES Permit # NC0004308/005
Stanly County
The aquatic toxicity test using composite samples of effluent discharged from the Alcoa Badin
Business Park Outfall 005 has been completed. Alcoa Badin Business Park Outfall 005 has a
permitted effluent discharge entering an unnamed tributary to Little Mountain Creek (7Q10 of
0.0 CFS). Whole effluent samples were collected on March 13 and March 15 by Roberto Scheller
for use in a chronic Ceriodaphnia dubia pass -fail toxicity test. The test passed. Toxicity test
information follows.
Test Type
Test Result
Test Concentrations
Control Survival
Control Mean Reproduction
Test Treatment Survival
Treatment Mean Reproduction
First Sample pH
First Sample Conductivity
First Sample Total Residual Chlorine
Second Sample pH
Second Sample Conductivity
Second Sample Total Residual Chlorine
3 -Brood Ceriodaphnia dubia chronic pass -fail
Pass
90%
83%
19.6 neonates
92%
25.8 neonates
7.30 SU
189.7 micromhos/cm
<0.1 mg/L
7.31 SU
245 micromhos/cm
<0.1 mg/L
Test results for the above samples indicate that the effluent would not be predicted to have
water quality impacts. These samples were split and tested by ETS, Inc. The chronic
Ceriodaphnia dubia pass/fail test run by ETS, Inc. resulted in a pass.
This facility was issued a new permit in the fall of 2017. The toxicity test requirement at Outfall
005 was changed from a chronic Ceriodaphnia dubia pass/fail test at 90% to an acute Fathead
minnow pass/fail test at 90%. Future tests should use the new permit testing requirements.
Please contact us if you have any questions or if further effluent toxicity monitoring is desired.
We may be reached at [phone].
Basin: Yadkin -Pee Dee
cc: Roberto Scheller (MRO)