ML20134C348
| ML20134C348 | |
| Person / Time | |
|---|---|
| Site: | Paducah Gaseous Diffusion Plant |
| Issue date: | 01/24/1997 |
| From: | Wooley R UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | Pierson R NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| GDP-97-0007, GDP-97-7, NUDOCS 9702030016 | |
| Download: ML20134C348 (2) | |
Text
/T'/
United States Enrichment Corporation 2 Democracy Center 6903 Rockledge Drive Bethesda. MD 20817 Tel. (301) 564-3200 Fax: (301) 564-3201 United Rates Enrichinent Corporation January 24,1997 Mr. Robert C. Pierson SERIAL: GDP 97-0007 Chief, Special Projects Branch Division of Fuel Cycle Safety and Safeguards, NMSS United States Nuclear Regulatory Commission Washington, D.C. 20555-0001 Paducah Gaseous Diffusion Plant (PGDP)
Docket No. 70-7001 Technical Safety Requirements Surveillance Criteria for Cascade Cell Trip Function
Dear Mr. Pierson:
As discussed with Mr. Dan Martin of your staff on January 24,1997, the purpose of this letter is to infonn you of an issue associated with a Technical Safety Requirement (TSR) Surveillance which was identified during our preparation for transition to the Enrichment Cascade at the Paducah Gaseous Diffusion Plant and to identify how USEC rcsolved this issue. This topic has also been discussed with Mr. Ken O'Brien.
The Enrichment Cascade Facility transitioned to the TSRs associated with these facilities on January 17,1997 at 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br />. As part of this facility transition, USEC implemented TSR 2.4.4.12, Cascade Cell Trip Function. Surveillance Requirement (SR) 2.4.4.12-8 requires the following:
Utilize the ACR " motor stop" button for planned "00" and "000" cell shutdowns and the motor breaker pistol grip at the local cell panel for planned C-310 cell shutdowns Approximately 90 percent of the cells at PGDP were in operation at the time of cascade facility O
transition. The remainder of cells were shutdown for various reasons. Most of the shutdown cells were not shutdown using the ACR motor stop button. As such, SR 2.4.4.12 could not be satisfied for gg these cells.
Nty /
In addition, the cells in operation at the time of facility transition also may not have been shutdown using the ACR motor stop button at the time of their last cell shutdown since utilization of the ACR motor stop button was not a requirement in the Operational Safety Requirements. Therefore, for those cells operating at the time of transition, the applicability of this SR was also qitestioned.
USEC utilizes Technical Safety Requirement Clarifications (TSRC) to clarify TSRs which may be ambiguous or unclear. The TSRC process is a procedu-alized process which is 'ntended to provide 9702030016 970124 PDR ADOCK 07007001 C
PDR intucky Portsmouth. Ohio Washington. DC
Mr. Robert C. Pierson January 24,1997 GDP97-0007 Page 2 additional guidance on, but not change, the TSRs. USEC performed a TSRC to clarify the applicability of this SR to shutdown and operating cells at the time of cascade transition. The results of this clarification are summarized below.
For the cells shutdown at the time of facility transition, the "00" and "000" cell restart procedures were revised to require testing of the ACR motor stop buttons prior to restart of shutdown cells. For j
the "00" cells shutdown at the time of facility transition, this testing consists of actuating the ACR l
push buttons to open the motor breakers thus verifying the ACR trip circuit functions properly. For the "000" cells shutdown at the time of facility operation, the testing consists of actuating the ACR motor stop button to open the 15kV Air Circuit Breaker to verify the cell trip function.
Those celis that were in operation at the time of the cascade facility transition remain in operation.
At the next planned cell shutdown, the requirements of SR 2.4.4.12-8 will apply and the ACR motor stop button will be utilized to effect cell shutdown.
Should you have any questions or require additional information, please contact me at (301) 564-3413 or Mark Smith at (301) 564-3244.
l Since.tely, u
i Robert L. Woolley Nuclear Regulatory Assurance and Policy Manager cc:
NRC Region III Office NRC Resident inspector - PGDP NRC Resident Inspector - PORTS DOE Regulatory Oversight Manager
.