HomeMy WebLinkAboutNC0056561_Whole Effluent Toxicity Test Results_20210811Division of Water Resources
August 11, 2021
MEMORANDUM
To: Landon Davidson
Water Quality Regional Operations, ARO
Through: Cindy A. Moore
Supervisor, Aquatic Toxicology Branch (ATB)
From: Lorimar S. Henning
Environmental Specialist II, Aquatic Toxicology Branch (ATB)
Subject: Whole effluent toxicity test results
Maggie Valley WWTP
NPDES Permit # NC0056561/001
Haywood County
The aquatic toxicity test using flow-proportional composite samples of effluent discharged from
the Maggie Valley WWTP has been completed. Maggie Valley WWTP has a permitted effluent
discharge of 1.0 million gallons per day (MGD) entering Jonathans Creek (7Q10 of 23.0 CFS).
Whole effluent samples were collected on July 20 and July 22 by Lauren Armeni and facility
representatives, Mike Mehaffey (ORC) and Seth Boyd, for use in a chronic Ceriodaphnia dubia
pass-fail toxicity test. The test passed. Toxicity test information follows.
Test Type 3-Brood Ceriodaphnia dubia chronic pass-fail
Test Result Pass
Test Concentrations 6%
Control Survival 100%
Control Mean Reproduction 27.7 neonates
Test Treatment Survival 100%
Treatment Mean Reproduction 28.3 neonates
First Sample pH 6.98 SU
First Sample Conductivity 343 micromhos/cm
First Sample Total Residual Chlorine <0.2 mg/L
Second Sample pH 6.78 SU
Second Sample Conductivity 3.26 micromhos/cm
Second Sample Total Residual Chlorine <0.2 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 Environmental Testing Solutions,
Inc. (ETS). The chronic Ceriodaphnia dubia pass/fail test run by ETS resulted in a pass. Please
contact us if you have any questions or if further effluent toxicity monitoring is desired. We may
be reached at cindy.a.moore@ncdenr.gov or lorimar.henning@ncdenr.gov.
Basin: French Broad
cc: Lauren Armeni (ARO)
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