ML20113D429
| ML20113D429 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 04/09/1985 |
| From: | Dixon O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20113D431 | List: |
| References | |
| NUDOCS 8504150288 | |
| Download: ML20113D429 (2) | |
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SOUTH CAROLINA ELECTRIC & GAS COMPANY POST OFPlCE 764 COLUMeiA SOUTH CAROUNA 29218 O. W. DIXON, JR.
April 9, 1985 v.Ci pR..o.m NUCLEAR OPERATIONS Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regu latory Commission (NRC)
Washington, D.C.
20555
Subject:
Virgil C. Summer Nuclear Station Docket No. 50/395 Operating License No. NPF-12 Removal of the Boron Injection Tank
Dear Mr. Denton:
South Carolina Electric and Gas Company hereby requests an amendment to the Virgil C. Summer Nuclear Station Technical Specifications.
This proposed change deletes specification 3/4.5.4, " Boron Injection System," modifies bases section B3/4.5.5, " Refueling Water Storage Tank," and incorporates the necessary changes to the Index as shown in Attachment A.
This proposed change will allow for the removal of the Boron Injection Tank (BIT) and other piping and components related to BIT operation.
Historically the BIT, which is required to maintain a mininum volume of highly borated water, has been a source of operations and maintenance problems at the Virgil C. Summer Nuclear Station. The heat tracing elements have been difficult to maintain operable, and frequent solidification of the acid in the sampling lines requires additional effort be expended to obtain required samples.
Two positive aspects surrounding removal of the BIT are the deletion of some heat tracing equipment and of the BIT safety relief valve.
Removal of the equipment used for heat tracing eliminates a potential fire hazard and thus reduces the possibility of a fire. Removal of the BIT safety relief valve eliminates one potential material release path and therefore reduces the possibility of an accidental hazardous material release.
To justify the proposed modification, the main steam line break analysis was reevaluated for the Virgil C. Summer Nuclear Station assuming the BIT was removed. A core analysis evaluation demonstrated that the departure from nucleate boiling ratio (DNBR) remained above 1.3 for this steam line break accident and that assumed f ailed fuel quantities remained the same. The evaluation demonstrated that the refueling water l
storage tank can supply sufficient negative reactivity to the core to f
counteract any positive increase in reactivity resulting from a cooldown in the reactor coolant system.
f l
$0 PDR ADOCK 05000395
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1 Mr. Harold R. Denton Page Two Apri1 9, 1985 Mass and energy release data was developed and utilized to evaluate containment environmental conditions resulting from the steamline break. Analysis of this information indicated that the containment is still bounded by original pressure and temperature limits upon removal of the BIT. New pipe rupture analysis also demonstrated that surrounding equipment important to safely shutdown the plant is not compromised.
Please find enclosed as Attachment B a no significant hazards determination.
This change has been reviewed and approved by both the Plant Safety Review Committee and the Nuclear Safety Review Committee.
Enclosed is the application fee of one hundred fif ty dollars ($150.00) required by Title 10 of the Code of Federal Regulations, Part 170.
If you have any questions, please contact us at your convenience.
y trfl[yours,
- 0. W AMM:0WD/tdh Attachment cc:
V. C. Summer T. C. Nichols, Jr./0. W. Dixon, Jr.
E. H. Crews, Jr.
E. C. Roberts W. A. Williams, Jr.
D. A. Nauman J. N. Grace Group Managers
- 0. S. Bradham C. A. Price C. L. Ligon (NSRC)
K. E. Nodland R. A. Stough G. Percival C. W. Hehl J. B. Knotts, Jr.
H. G. Shealy NPCF File l
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