TXX-3997, Advises That Environ Qualification Program for safety- Related Electrical Equipment Will Be Completed Prior to Fuel Load.Util in Compliance w/10CFR50.49 & Committed to Remain So Even Though Design Grandfathered
| ML20024B068 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 06/28/1983 |
| From: | Schmidt H TEXAS UTILITIES SERVICES, INC. |
| To: | Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0588, RTR-NUREG-588 TXX-3997, NUDOCS 8307050064 | |
| Download: ML20024B068 (3) | |
Text
TEXAS UTILITIES SERVICES INC.
log # TXX-3997 amouww nmu mu.amw n2w-Fi1
- 903.11 June 28, 1983 Director of Nuclear Reactor Regulation Attention: Mr. B. J. Youngblood, Chief Licensing Branch No. 1 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION DOCKET NOS. 50-445 AND 50-446 ENVIRONMENTAL QUALIFICATION 10 CFR PART 50.49 REF:
(1) " Guidelines for Evaluating Environmental Qualification of Class IE Electrical Equipment in Operating Reactors" November 1979 (00R Guidelines)
(2) NUREG-0588 (For Comment version), " Interim Staff Position on Environmental Qualification of Safety-Related Electrical Equipment"
Dear Sir:
On Jcnuar/ 21, 1983, the new rule on environmental qualification (10 CFR Part 50.49, see Federal Register /Vol. 48, No.15/2729) was published and became effective on February 22, 1983. Paragraph (i) in this new rule requires that operating license applicants who expect to receive their license after February 22, 1983, and before November 30, 1985, must perform and submit an analysis to demonstrate that the plant can be safety operated until the applicable requirements of this rule are met.
Texas Utilities as the operating license applicant for Comanche laak Steam Electric Station (CPSES) is in this category.
The applicable requirements of the rule for CPSES are provided in paragraph (k) of the rule. Paragraph (k) allows that equipment does not need to be requalified in accordance with the new rule if the qualification of that equipment had been previously encompassed by the scope of references (1) or (2).
The qualification effort at CPSES is encompassed by the scope of reference (2).
The status of the CPSES environmental qualification program is described in the CPSES Final Safty Analysis Report (FSAR), Appendix 3A.
8307050064 830628 AO PDR ADOCK 05000445 A
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It is the intent of Texas Utilities to complete this qualification program prior to fuel load. Any equipment whose qualification is not complete prior to fuel load will be identified and an analysis will be performed and submitted to demonstrate that the plant can be safely oper ated until the qualification for these items is completed.
This analysis will be subpitted for consideration prior to the CPSES fuel load.
Even though the CPSES environmental qualification program has been
" grandfathered" by 10 CFR Part 50.49(k), as described above, some discussion is appropriate on the scope of the new rule as it relates to CPSES.
Paragraph (b) of the new rule describes the scope as that equipment which is "important to safety" including safety-related (Class IE) equipment, nonsafety-related equipment (whose failure during harsh environmental conditions could adversely affect safety) and some accident monitoring instrumentation. This same scope of equipment has been considered in evaluating the safety of CPSES.
The CPSES definition of safety-related is consistent with the definition given in 10 CFR 50.49(b)(1).
Safety-related equipment and systems have been subjected to a very rigorous and thorough program.
Many design, perfomance, handling, quality asssurance and operational aspects have been considered, including environmental qualification.
For safety-related electrical equipment, a rigorous environmental qualification program was established and is being implemented.
For safety-related mechanical equipment, the procurement process specifically addresses environmental concerns. The maintenance and surveillance programs include actions that will help assure that all safety-related equipment can perform their required functions.
The potential that nonsafety-related equipment could adversely affect safety was a basic consideration in the design of CPSES.
The failure of nonsafety-related equipment, from whatever cause, has been considered.
For example, separation criteria has been established to ensure that the failure of nonsafety-related equipment will not affect safety-related power supplies and safety-related electrical distribution systems. Safety-related electrical power systems and instrumentation and control systems are designed in accordance with Institute of Electrical and Electronics Engineers (IEEE) std. 308-1974 and IEEE std. 279-1971 respective as discussed in the CPSES FSAR.
Physical inspections have been conducted to ensure that missiles will not be generated and that the mechanical failure of nonsafety equipment (e.g., falling during a seismic event) will not adversely affect safety-related systems and equipment. Nonsafety-related control systems were examined in light of postulated adverse environments to ensure that the controls do not react in a manner that may be adverse
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to safety. This analysis was performed in response to NRC question 032.107 in the CPSES FSAR which was based on Office of Inspection and Enforcement (IE) Infomation Notice 79-22. The results of this analysis have been found acceptable by the NRC Staff (See CPSES SSER 2, Section 7.7.2).
These specific studies all contribute to the basic design philosophy of independence and separation between safety-related and nonsafety-related systems and equipment. The CPSES separation criteria are discussed in Section 8.3.1.2.1 of the CPSES FSAR and have been found acceptable by the NRC Staff (See CPSES SER Section 8.4.5).
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o Accident monitoring equipment has been addressed by CPSES in Section 7.5 of the CPSES FSAR. Using the basic guidance provided by U. S.
Nuclear Regulatory Guide 1.97, Revision 2, the accident monitoring equipment for CPSES was selected.
It was judged proper to environmentally qualify some of this equipment, even though the equipment may be nonsafety-related, either to increase their availability or to ensure that the function of safety-related systems was not adversely affected.
Such accident monitoring equipment was included in the scope of our equipment qualification program as soon as they were identified.
In conclusion, CPSES is in compliance with 10 CFR Part 50.49 and is committed to remain so even though the present design of CPSES has been
" grandfathered" from the technical requirements in this new environmental qualification rule. The scope defined in the new rule does not exceed the efforts previously expended for CPSES. The analyses required to justify safe plant operation, if the qualification of any equipment is not complete, will be provided for consideration before CPSES fuel load.
espectfully, H. C. Schmidt DRW: tis cc:
S. B. Burwell Hukam Garg a