ML20006B700
| ML20006B700 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 01/26/1990 |
| From: | William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-89-13, TXX-90031, NUDOCS 9002050268 | |
| Download: ML20006B700 (9) | |
Text
{{#Wiki_filter:_ _ _ M -M Log # TXX 90031 File # 10119 (({ }(( Ref. # Generic Letter 89-13 NELECTRIC January 26, 1990 WMase J. Cahm, Jr. Esecutive Vke hesiderst U. S. Nuclear Regulatory Commission Attn:. Document Control Desk Washington, D. C. 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES) DOCKET NOS. 50 445 AND 50-446-NRC GENERIC LETTER 89-13 SERVICE. WATER SYSTEM PROBLEMS AFFECTING SAFETY RELATED EQUIPMENT Gentlemen: The following information is provided in response to the NRC Generic Letter 89-13 " Service Water System Problems Affecting Safety Related Equipment" (GL 89 13). (1) CPSES RESPONSE TO GL 89-13. ACTION (1): For open-cycle Service Water Systems. CPSES meets the following provisions of the program recommended in Enclosure 1 of GL 8913: (a), item A: The intake structure should be visually inspected, once per refueling cycle, for macroscopic biological fouling organisms (for example, blue mussels at marine plants, American oysters at estuarine plants, and Asiatic class at freshwater plants), sediment, and corrosion. Inspections should be performed either by scuba divers or by dewatering the intake structure or by other comparable methods. Any fouling accumulations should be' removed. CPSES Response to Enclosure 1. Item A: CPSES has implemented preventative maintenance activity which calls for inspection of the Service Water intake structure by u SCUBA diver which will be performed at-least once per fuel cycle. Any. significant accumulation of silt and debris (such as clams) encountered will be removed. (b) Enclosure'1, Item B: The Service Water System should be continuously (for example,[during' spawning); chlorinated (or equally effectively. treated with another biocide' whenever the potential for a macroscopic biologica1' fouling 9002050268 900126 S PDR ADOCK 05000445 A PDC .j g P. O. Boa 1002 Glen Rose, Texas %oO 1002 Fr V /[ /; j.
TXX 90031 January 26, 1990 Page 2 of 5 species exists (for example, blue mussels at marine plants. American oysters at estuerine plants, and Asiatic clams at freshwater j plants)._ Chlorination or equally effective treatment is included i for freshwater plants without clams because it can help prevent I microbiological 1y influenced corrosion. However, the chlorination (or equally effective) treatment need not be as stringent for plants j where the potential for macroscopfc biological #ouling species does not exist compared to those plants where it does. Precautions should be taken to obey Federal, State and local environmental l regulations regarding the use of biocides. l 1 CPSES Response to Enclosure 1. Item B: l CPSES will use a biocide injection system to control adverse. I biological growth in_the Service Water System. CPSES presently uses biocide injection and a bromine based chemistry (rather than l chierine). Indications to date are that the treatment is effective. The chemicals used in the Service Water System have_been evaluated and determined to be in compliance with applicable envionmentai regulations, i (c) Item C: i i Redundant and infrequently used cooling loops should be flushed and l flow tested periodically at the maximum design flow to ensure that they are not fouled or clogged. Other components in the Service-Water System should be tested on a regular schedule to ensure that they are not fouled or clogged. Service water cooling loops should i be filled with chlorinated or equivalently treat d water'before l layup. Systems that use raw service water as A ';ource, such as some fire protection systems, should also be chlorinn ed or equally i effectively treated before layup to help prevent microbiological 1y influenced corrosion. Precautions should be'taken to obey Federal, State, and local environmental regulations regarding the use of biocides. l CPSES Response to Enclosure 1. Item C: L Loops supplied by the Service Water System at CPSES. with the l l exception of the Auxiliary feedwater connection,-see continuous flow in order to maintain a good mix of corrosion inhibition chemicals i and biocides. and to prevent stagnant conditions,which are conducive to microbiological attack and fouling. The plant operating i procedure provides for chemical treatment of the system prior _to 1ayup. The chemicals used in the Service Water System have been ~ i evaluated and determined to be in compliance with applicable. environmental regulations. The connection to Auxiliary Feedwater cannot be flow tested due to l the potential for transporting ' raw' water to the steam generators. Instead TV Electric will perform visual examination when the check j valves in these areas are disassembled for their inservice testing (IST) inspections. 1 ? i (
t TXX 90031 'I January 26, 1990 ) Page 3 of 5 i (d), Item D: l 9 Samples of water and substrate should be collected annually to determine if Asiatic clams have populated the water source. -Water j and substrate sampling is only necessary'at freshwater plants that i have not previously detected the presence of Asiatic clams in their source water bodies. If Asiatic clams are detected, utilities may. discontinue this sampling activity if desired, and-the chlorination-(or equally effective) treatment program should be modified to be in i agreement with paragraph B, above, i t CPSES Response to Enclosure 1. Item 0: In response to IE Bulletin 81-03, TV Electric committed -(via letter logged TXX-3352 and TXX-3649) to semi-annual monitoring tf the Squaw i Creek Reservoir (SCR) and the Safe Shutdown Impoundment (SSI) for. Corbicula. The TV Electric response further stated that upon' detection of Corbicula in significant. numbers, the monitoring T program might be discontinued and that appropriate treatment methods-t would be implemented, i The monitoring program was initiated in May 1981, and discontinued subsequent to initial detection of Corbicula in 1984. TV Electric has implemented a biocide, treatment program as mentioned in the response to Item B above, j (2) CPSES RESPONSE TO GL 8913. ACTION (II): ? l The safety related heat exchangers supplied by Service Water System' f l include the Component Cooling Water (CCW) heat exchangers, the Diesel Generator Jacket Water (DGJW) heat exchangers, the Safety Injection (SI) lube oil coolers, the Centrifugal Charging Pump (CCP) lube oil. coolers,= l and the Containment Spray (CT) pump. lube oil coolers, j The CCW and DGJW heat exchangers will'be tested in accordance with " Heat Exchanger Performance Monitoring Guidelines for Service-Water Systems" (EPRI Interim Report, July 1989), The CCP, CT and SI pump' lube oil oolers will not be testad. However, lube oil temperature will be recorded during monthly surveillance runs of the associated pumps and the trends will be analyzed _ quarterly. In. j addition, these heat exchangers will be visually inspected at least once' L every three years. Service water flowrates to these. components will be-P monitored on a weekly basis to~ verify that the flow rates meet design requirements. l <t i i I n
i TXX 90031 j - January 26, 1990 Page 4 of 5 (3) CPSES RESPONSE TO GL 89 13. ACTION (Ill)* The " Corrosion Monitoring Program, Service Water Subsection" has been i developed to provide a means by which samples of Service Water System piping wall thickness will be' periodically measured and trended, to identify and correct any detrimental thinning. In addition, periodic preventative maintenance activities are in place to clean the various strainers in the system. Any type of significant foreign debris introduced into the system will be detected during the strainer work. A preventative maintenance activity also exists in which the channel heads on the CCW heat exchangers-are opened. Any accumulation of debris would be detected and removed during this activity, i (4) CPSES RESPONSE TO GL 89-13. ACTION (lyh. l The functional requirements of the Service Water System are' established in l the project design basis document and have been reviewed in detail.within t the last two years. The review confirmed that the Service Water Syt, tem > will perfrom its intended function in accordance with the licensing basis for the plant, i Each CPSES unit has an independent Servi.ce Water System in accordance with 10 CFR 50, Appendix A. GDC 5. Each Service Water System consists of two separate and independent full capacity safety related trains. Each-train provides cooling water to and removes rejected heat from, separate CCW heat exchangers, Safety Injection and Centrifugal Charging Pump lube oil i coolers Diesel Generator Jacket Water coolers and Containment Spray pump lube oil coolers. Each train also provides water to its associated Service Water pump in order to' lubricate its bearings. In addition, each train provides an emergency source of cooling water to-the Auxiliary Feedwater System. The Service Water System provides sufficient cooling to - t these heat exchangers for emergency and normal operation of the plant, j The redundant trains and components are provided to meet the requirements that a single failure will not interrupt cooling water to' equipment required for safe shutdown. In case of failure of Unit 1 train 'A' and. 'B' Pumps, Unit 2 pumps are available, t The functional requirements described above are implemented:in. the design. of the Service Water System as depicted in the system flow diagrams. A i l set of piping isometric drawings that correspond'to the flow diagrams show the physical layout of the system. There have 31so been a number of reviews performed to assure that the as-built configuration of the Service Water System is consistent with the design basis for example, in order to satisfy the requirements of IE: Bulletin 79-14, the as-bidit information has been generated within the.. past 2 years for the piping'and in-line components that are shown on the i isometric drawings. This system walkdown data is documented in' stress analysis problem boundary packages, and retained in plant permanent records. l - ~
'TXX-90031 i January 26, 1990 Page 5 of 5 i (5) CPSES RESPONSE TO Gt 89-13. ACTION (V): [ i A CPSES administrative procedures require that quality related procedures t (which include procedures affecting maintenance, operation and emergency i procedures, and training that involve the Service Water System) be reviewed by an individual knowledgeable in the area affected by the l procedure to determine it. any changes or updates are required. Presently. l this review is required no less frequently than every two years. 'In 1 addition, the CPSES operator requalification program provides for. retraining of operators to ensure that they are cognizant of any system modifications or procedure changes affecting the Service' Water System. 811 action items from this response to Generic Letter 8913 mill be completed by May 15, 1990 for Unit 1 and oy Unit 2 fuel load for Unit 2. . TV Electric will provide the written notification required by Generic Letter 89 13 to NRC l within 30 days af ter completion of all action items for each Unit. Supporting documentation for the GL 69 13 will be available at the CPSES site for NRC + review after completion of all action items for each Unit. Sincerely, { Williem J. Cahill, Jr. MCP/smp Attachment l c - Mr. R. D. Martin, Region IV Resident Inspectors, CPSES (3) i ~. I I l l \\ i 1l i l t t L i 4 a f -. - 1
I l l l Attachment I to TXX-90031 l January 26, 1990 j Page 1 of 1 j [ UNITED STATES OF AMERICA NUCLEAR REGULATORY. COMMISSION ~ i in the Matter of l Texas Utilities Electric Company Docket Nos. 50 445 50-446 (Comanche Peak Steam Electric i Station, Units 1 & 2) j AFFIDAVIT William J. Cahill, Jr. being duly sworn, hereby deposes and says that he is 7 Executive Vice Presidtnt, Nuclear of TU Electric, the leaa Applicant herein; that ha is duly authorized to sign and file with the Nuclear Regulatory Commission this response to NRC Generic Letter 89-13; that he is familiar with the content thereof; and that the matters l set-forth therein are true and j correct to the best of his knowledge,. information and belief. i .l , ). AM a // . William J. CahfIl, Jr."'.7f ' '. Executive Vic6 President,' Nuclear .j -{ i E STATE OF TEXAS COUNTY OF S&ERval Subscribed and sworn to before me, a Notary Public, on this 25TH day of 1990. cranmrv .Ct -~ ~ Notary Public g j w ccer.aou EpmEt, March 16,1993 l' &w_. 1 2,..-. ~ .. -}}