ML030910207

Total Residual Oxidant Release from ERCW Pumping Station, Outfall 117, SQN Ndpes Permit No.TN0026450

ML030910207
Person / Time
Site:	Sequoyah
Issue date:	03/17/2003
From:	Beavers M Tennessee Valley Authority
To:	Davis P Office of Nuclear Reactor Regulation, State of TN, Dept of Environment & Conservation, Div of Radiological Health
References
TN0026450
Download: ML030910207 (3)

Text

Tennessee Valley Authority, Post Office Box 2000, Soddy-Daisy, Tennessee 37384-2000 March 17, 2003 State of Tennessee Department of Environment and Conservation Division of Water Pollution Control Enforcement & Compliance Section 6 th Floor, L&C Annex 401 Church Street Nashville, Tennessee 37243-1534 Attention: Mr. Paul E. Davis, Director

Dear Mr. Davis:

TENNESSEE VALLEY AUTHORITY - TOTAL RESIDUAL OXIDANT RELEASE FROM ERCW PUMPING STATION, OUTFALL 117, SQN NDPES PERMIT NO. TN0026450 Please find enclosed a copy of the incident report regarding the Total Residual Oxidant release from ERCW Pumping Station, Outfall 117, SQN NDPES Permit No. TN0026450.

I certify under penalty of law that this document and all attachments were prepared under the direction of supervision in accordance with a system designed to assure that qualifiedpersonnelproperlygatherand evaluate the infonmation submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine or imprisonment for knowing violations.

Please contact me at (423) 843-6700 or by E-mail at mgbeavers@tva.gov with any questions regarding this matter.

Sincerely, Michael G. Beavers Acting Environmental Supervisor Signatory Authority for Richard T. Purcell Vice President Sequoyah Nuclear Plant Enclosure cc: See page 2 Pnted on recycled papw

Mr. Paul E. Davis Page 2 March 17,2003 cc (Enclosure):

Chip Hannah State of Tennessee Department of Environment and Conservation Division of Water Pollution Control Enforcement & Compliance Section 6th Floor, L&C Annex 401 Church Street Nashville, Tennessee 37243-1534 Chattanooga Environmental Assistance Center Division of Water Pollution Control State Office Building, Suite 550 540 McCallie Avenue Chattanooga, Tennessee 37402-2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555

TOTAL RESIDUAL OXIDANT RELEASE FROM ERCW PUMPING STATION, OUTFALL 117, SQN NDPES PERMIT NO. TN0026450 INCIDENT:

On 3/10/2003 there was an incident in which a backwash of ERCW strainer B1 B-B was performed concurrently with injection of raw water treatment chemical (Towerbrom 960). This incident may have released treated water via Outfall 117 which is a noncompliance of SQN NPDES Permit No. TN0026450.

BACKGROUND:

3110/2003 ERCW strainer B2B-B was tagged, with tagging being completed at 0407 on 3/10/2003 under clearance 0-67-155 WAW. The process of tagging this strainer includes placing the ERCW strainer B1 B-B in continuous backwash. The water from the strainer continuous backwash exits the SQN site through Outfall 117. If ERCW Towerbrom 960 treatment is being performed in the B-train ERCW pump wells during B-train strainer backwash, then treated water may be released via an outfall not allowed for treated water discharge in the SQN NPDES Permit No. TN0026450. B-train ERCW was treated with Towerbrom 960 at a concentration of approximately 0.4 mg/L TRO on 3/10/2003 from 0830-1210 with a strainer backwash flow rate of 500-600 gpm.

Therefore, there is a potential that effluent containing this TRO was released from Outfall 117. The continuous backwash was not identified during the period of Towerbrom 960 treatment and therefore no samples of Outfall 117 discharge were taken.

3/12/2003 This condition was discovered by Ondeo/Nalco Vendor on 3/12/2003 at approximately 0900 after communications with ERCW System Engineer about the need to perform an ERCW traveling screen backwash.

Corrective Actions:

1. Problem Evaluation Report (PER) 03-002479-000 was written on 3/12/2003.

2. Environmental Technicians performed a downstream inspection of the river for any indication of aquatic distress. This inspection did not indicate any signs of aquatic distress.