ML19340A952
| ML19340A952 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 08/09/1976 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19340A949 | List: |
| References | |
| NUDOCS 8009100797 | |
| Download: ML19340A952 (3) | |
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[puog*g UNITED STATES O"
't NUCLEAR RECULATORY COMMISSION WASHINGTON, D. C. 20555
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 17 TO FACILITY LICENSE NO. DPR-2 C0hMONWEALTH EDISON COMPANY DRESDEN NUCLEAR POWER STATION UNIT 1 DOCKET NO. 50-10 INTRODUCTION By letter dated March 11, 1976, the Commonwealth Edison Company (CECO) requested an amendment to Facility License No. DPR-2 for the Dresden Nuclear Power Station Unit No. 1 facilicy.
This request involves changes to the Technical Specifications with regard to the requirements for primary containment integrity.
DISCUSSION The existing Technical Specification 3.7.A requires primary cont.inment integrity "at all times except when all the following occur simultaneously:
a.
All control rods inserted.
b.
No work is being done on the primary system.
c.
No work ir, being done in the canal over the reactor vessel.
d.
No fuel is being transferred within or out of primary containment."
The bases to Specification 3.7.A state that:
..., containment integrity is specified whenever the potential for violation of the primary reactor system integrity exists.
Concern about such a violation exists whenever the reactor is critical and above atmospheric pressure.
In addition, even during periods when the reactor is shutdown, primary containment integrity is required to ensure that fission products would be contained in the. event of a refueling accident or large spill of radioactive water from the primary system".
By letter dated January 8,1976, the NRC staff (the " staff") requested that CECO add:
"e.
The reactor water temperature is less than 212 0F."
to the listed conditions, a to d above.
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l In responding to our request, CECO requested other changes to the specifications in addition to our requested item e.
The requested changes have been modified by the staff to meet our requirements.
These modifications have been discussed with the licensee and they have agreed with our changes.
EVALUATION The proposed Specification 3.7.A, as modified, would revise the existing conditions a to d discussed above and would add the staff requested condition e7 Three of the listed conditions (a, e and d) would not be applicable when fuel is removed from the reactor Fessel or containment.
The proposed item a would specify that containment integrity be maintained whenever one or more control rods is withdrawn from the inserted position.
This assures that containment is available whenever the reactor could be critical. The proposed item a_ would accomplish the same purpose as the existing item a_ and is acceptable.
The proposed item b would specify that containment integrity be maintained whenever work whicE has the " potential of draining the reactor vessel" is in progress on the primary system.
This condition would assure that containment is available when work 12 in progress which could uncover the reactor fuel or dump the reactor vessel water into the containment.
We conclude that the proposed item b, satisfies the safety concerns stated in the bases (described above) and is acceptable.
The proposed item c,would specify that containment integrity be maintained when work is in progress over the reactor vessel and, the vessel head is removed. This provision would protect the reactor fuel (if present) from damage which could be incurred if a heavy object is dropped over the reactor vessel. With the vessel head in place the fuel vould be protected, thus work over the vessel could not damage the reactor fuel and would not_ require that containment integrity be maintained.
Based on these considerations, we find the proposed item c, acceptable.
The proposed item d, would specify that containment integrity be maintained whenever fuel is transferred within containment.
This would assure that containment is available during the time when a fuel handling accident is most likely.
The proposed item d accomplishes the same purpose as the existing item d,and is acceptable.
The proposed item e,would specify that containment integrity be maintained whenever the reactor water temperature is equal to or greater than 212 oF.
This condition assures that containment is available when a primary system leak could cause primary water to flash to steam within
T containment. This release could lead to uncovering the reactor fuel (if present) and ' emptying of the reactor vessel.
Based on the above considerations, we find the proposed item e acceptable.
The proposed Specification 3.7.A'would allow the licensee to omit three of the above discussed conditions for containment integrity when no fuel is present in the reactor vessel or containment.
The proposed item a assures that the reactor is maintained subcritical by having all control rods inserted.
With no fuel in the reactor vessel, the reacter cannot be made critical therefore the control rods need not be inserted.
The proposed item c involves the potential for fuel damage when work is being performed ove; an open reactor vessel. With no fuel in the vessel this provision wo Id be unnecessary. The proposed item d is obviously not required with no fuel inside containment.
Based on these considerations, we conclude that the proposed items a, e and d would not be required with all fuel removed from the reactor vessel or containment.
Based on the above considerations, we have concluded that the proposed Specification 3.7.A, as modified, is acceptable.
We have determined that the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and wirl not result in any significant environmental impact.
Having made this determination, we have further concluded that the mnendment involves an action uh' h is insignificant from the standpoint of environmental impact and pursuant to 10 CFR 551.5(d)(4) that an environmental statement, negative declaration, or environmental impact appraisal need not be prepared in connection with the issuance of this amendment.
CONCLUSION We have concluded, based on the considerations discussed above, that:
(1) because the changes do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a significant decreas: in a safety margin, the changes do not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be ' endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the common defense-and security or to the health and safety of the public.
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Date:
August 9, 1976
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