NC0047384_Toxicity Test Results_20200813

ROY COOPER
Governor
MICHAEL S.REGAN
Secretary
S.DANIEL SMITH NORTH CAROLINA
Director Environmental Quality I
I
August 13, 2020
Mr. Mike Borchers, Director
Water Resources Department
City of Greensboro
P.O. Box 3136
Greensboro,NC 27402-3136 k
Subject: Toxicity Test Results
City of Greensboro -T.Z.Osbome POTW
NPDES Permit No. NCO047384
Guilford County
Dear Mr. Borchers:
Please find attached a copy of the toxicity test results for samples obtained from the T.Z. Osborne
effluent. Aliquots from Greensboro's composite samples were collected on July 7 and 9, 2020 by
Mike Mickey and Jordan Burbage of this office for use in a chronic Ceriodaphnia dubia pass/fail
toxicity test conducted by the Division's Aquatic Toxicology Branch laboratory. The T.Z. Osbome
POTW effluent passed this test at an effluent concentration of 90%. The sample was split with
Meritech Environmental Laboratories for Greensboro's quarterly testing requirement. Meritech's
test result was also a pass.
Should you have any questions concerning this report, please do not hesitate to contact Mr. Mike
Mickey at(336) 776-9692 or at [e-mail]. Our office appreciates the assistance of
the W WTP staff in collecting the samples.
Sincerely,
Lon T. Snider, Regional Supervisor
Water Quality Regional Operations Section
Division of Water Resources,NCDEQ
Enclosure: Toxicity Test Results
i
cc: Marti Groome ([e-mail])
WSRO
QZ North Carolina Department of Environmental Quality I Division of Water Resources III
`6T Winston-Salem Regional Office 1 450 West Hanes Mill Road,Suite 3001 Winston-Salem,North Carolina 27105
vnamnemma,.ve„m�eiwenq 336,776.9800

Division of Water Resources
July 27, 2020
MEMORANDUM
To: Lon Snider
Water Quality Regional Operations,WSRO
Through: Cindy A. Moore v�
Supervisor,Aquatic Toxicology Branch(ATB)
From: Lorimar S. Henning 6*1('
Environmental Specialist II,Aquatic Toxicology Branch(ATB)
Subject: Whole effluent toxicity test results
Greensboro Osborne WWTP
NPDES Permit#N00047384/001
Guilford County
I
i
The aquatic toxicity test using flow-proportional composite samples of effluent discharged from
the Greensboro Osborne WWTP has been completed. Greensboro Osborne WWTP has a
permitted effluent discharge of 40 million gallons per day(MGD)entering S. Buffalo Creek(7Q10
of 2.1 CFS). Whole effluent samples were collected on July 7 and July 9 by Mike Mickey and
facility representative Alicia Goots 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 90%
Control Survival 91.7%
Control Mean Reproduction 23.3 neonates
Test Treatment Survival 91.7%
Treatment Mean Reproduction 24.7 neonates
First Sample pH 7.71 SU
First Sample Conductivity 799 micromhos/cm
First Sample Total Residual Chlorine 0.02 mg/L
Second Sample pH 7.85 SU
Second Sample Conductivity 832 micromhos/cm
Second Sample Total Residual Chlorine 0.02 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 Meritech, Inc. The chronic
Ceriodaphnia dubia pass/fail test run by Meritech 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 f
[phone].
Basin: Cape Fear
cc: Mike Mickey(WSRO)