ML053390078
| ML053390078 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/29/2005 |
| From: | Joseph E Pollock Constellation Energy Group, Constellation Generation Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-04-002 | |
| Download: ML053390078 (2) | |
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11 Calvert Cliffs Nuclear Power Plant Constellation Generation Group, LLC 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 Constellation Energy November 29, 2005 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
SUBJECT:
Document Control Desk Calvert Cliffs Nuclear Power Plant Unit Nos. I & 2; Docket Nos. 50-317 & 50-318 Supplemental Response to NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation during Design Basis Accidents at Pressurized-Water Reactors"
REFERENCES:
(a) Letter from Mr. G. Vanderheyden (CCNPP) to Document Control Desk (NRC), dated August 30, 2005, Response to NRC Generic Letter 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation during Design Basis Accidents at Pressurized-Water Reactors" (b) NEI-04-07, Pressurized-Water Reactor (PWR)
Sump Performance Methodology, dated May 28, 2004 The primary purpose of this letter is to supplement our August 30, 2005, response to Generic Letter 2004-02 (Reference a) to address issues raised by the Nuclear Regulatory Commission (NRC) at a public meeting on September 30, 2005. Specifically, we address the impact of the recently completed chemical effects testing on our justification for continued operation contained in Attachment (2) of our August 30, 2005, response.
As part of the efforts to resolve Generic Safety Issue-191, the NRC has conducted tests at Argonne National Labs to determine the magnitude of the impact of chemical precipitation which might occur in the containment sump pool during post-loss-of-coolant accident (LOCA) recirculation. One of the tests examined the interaction of calcium-silicate insulation with a Trisodium Phosphate (TSP) sump pool buffer agent. The results showed that a chemical precipitant did form and the impact on strainer headloss was significant. Those plants containing both calcium-silicate insulation and TSP buffering agent were identified by the NRC/ Nuclear Energy Institute (NEI) as needing to address the impact of this result on plant operability including the need to implement additional compensatory measures.
Calvert Cliffs Units I and 2 were among the plants identified as having calcium-silicate insulation and TSP buffering agent. However, Calvert Cliffs has no calcium-silicate insulation in the zone of influence of the LOCA break; therefore, per NEI 04-07 (Reference b) no calcium-silicate insulation will be destroyed during the LOCA, and thus none will transport to the containment sump pool. Since there is no calcium-silicate insulation in our containment sump pool the results of the Argonne National Labs chemical effects testing has no impact on plant operability.
Document Control Desk November 29, 2005 Page 2 Additionally, we would like to inform you that due to uncertainties in the chemical effects testing, our design process is not as far along as we had anticipated.
As a result, the schedule we stated in Reference (a) for submitting a license amendment request for the additional Technical Specification Surveillance Requirement has changed from December 31, 2005 to July 1, 2006. This change does not impact the completion schedule for corrective actions reported in Reference (a).
Should you have questions regarding this matter, please contact Mr. L. S. Larragoite at (410) 495-4922.
Very truly yours, STATE OF MARYLAND COUNTY OF CALVERT
- TO WIT:
I, J. E. Pollock, being duly sworn, state that I am Plant General Manager - Calvert Cliffs Nuclear Power Plant, Inc. (CCNPP), and that I am duly authorized to execute and file this response on behalf of CCNPP.
To the best of my knowledge and belief, the statements contained in this document are true and correct.
To the extent that these statements are not based on my personal knowledge, they are based upon information provided by other CCNPP employees and/or consultants.
Such information has been reviewed in accordance with company practice and I believe it to be reliable.
Subscribed and sworn before me, a Notary Public in and for the State of Maryland and County of C6JvtVT
,this 6aI day of Aov8mE£R
,2005.
IItiS y Hnd and Notarial Seal:
My Commission Expires:
IOlA Y PUBLIC Calvert County, Maryland My Commission Expires 01/01/06 Date JEP/GT/bjd cc:
P. D. Milano, NRC S. J. Collins, NRC Resident Inspector, NRC R. I. McLean, DNR