ML20058J076
| ML20058J076 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 11/24/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20058J068 | List: |
| References | |
| NUDOCS 9312130367 | |
| Download: ML20058J076 (4) | |
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,k UNITED STATES j
.j NUCLEAR REGULATORY COMMISSION
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WASHINGTON, D.C. 205564XC1
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATIM RELATED TO AMENDMENT NOS. 170 AND 153 TO FACILITY OPERATING LICENSE NOS. DPR-51 AND NPF-6 ENTERGY OPERATIONS. INC.
i ARKANSAS NVCLEAR ONE. UNIT NOS. 1 AND 2 i
DOCKET NOS. 50-313 AND 50-368 f
1.0 INTRODUCTION
By [[letter::0CAN079302, Application for Amends to Licenses DPR-51 & NPF-6,revising ANO Unit 1,limiting Conditions for Operation,Surveillance Requirements,Bases for ECP & ANO Unit 2 Surveillance Requirements & Bases for ECP|letter dated July 28, 1993]], Entergy Operations, Inc. (the licensee) submitted a request for changes to the Arkansas Nuclear One, Unit Nos. I and 2 (ANO-l&2), Technical Specifications (TSs). The requested changes would revise the AND-l&2 TSs for the Emergancy Cooling Pond (ECP) to achieve consistency between the ANO-1 and ANO-2 TSs and clarify the point at which the water temperature is verified for the ECP. The applicable Bases would also be revised to reflect the changes and clarify the TSs.
l 2.0 EVALUATION 2.1 Chances to ANO-1 TSs i
The mode of applicability has been revised to require ECP operability whenever containment integrity is established. The existing ANO-1 TSs require the service water system to be operable whenever the reactor coolant is at 300 psig or greater, 200 degrees F or greater, and nuclear fuel is in the core.
However, the existing TSs do not require the ECP to be operable until the reactor is critical (this is well beyond the heat-up point discussed in the previous sentence). Requiring the ECP portion of the ultimate heat sink to be operable whenever containment integrity is required will ensure that the back-up water source to the Dardanelle Reservoir, the ECP, is available whenever the service water system is required. This change results in a more stringent i
requirement for ECP operability than the existing TSs, is consistent with the
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AND-2 TSs, and is, therefore, acceptable.
The existing required minimum average water depth of the ECP (3 feet) has been revised to a minimum contained water volume of 70 acre-feet (equivalent to an indicated water level of 5 feet), and the existing maximum average water temperature of 105 degrees F has been revised to 100 degrees F.
The existing i
ANO-1 TSs considered only the ANO-1 Design Basis Accident heat load (AND-2 was in the operating license review stage the last time this TS was revised).
l Analyses performed in support of the ANO-2 operating license determined that the design basis of the ECP was bounded by a simultaneous normal shutdown of AND-1 and emergency shutdown of ANO-2 following a loss-of-Coolant Accident in ij ANO-2.
This resulted in the current AND-2 TS requirements for a minimum 9312130367 931124 PDR ADOCK 05000313 P
PDR I
. contained water volume of 70 acre-feet (equivalent to an indicated water level of 5 feet) and a maximum average water temperature of 100 degrees F.
This change results in more stringent requirements for ECP operability than the existing TSs, is consistent with the AND-2 TSs, snd is, therefore, acceptable.
The existing surveillance which requires verification, every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, of an average water depth of at least 3 feet has been revised to an indicated water level of at least 5 feet. The change to 5 feet was discussed above. The change from " average water depth" to " indicated water level" clarifies the TSs. Acceptable average water depth is verified if the indicated level on the level measuring device is greater than 5 feet. This is acceptable since the level measuring device is calibrated to the value obtained in the annual soundings. Also, use of the term " average" could be interpreted as requiring-two or more level measurements in order to arrive at an average value. Since the average depth and total contained water volume is verified annually by sounding, and since the level measuring device is calibrated to the sounded average depth, there is no change in intent of the specification. Therefore, this change corrects a possible source of confusion, is consistent with the ANO-2 TSs, and is, therefore, acceptable.
The existing surveillance to verify that the average water temperature is no greater than 105 degrees F at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> during the period from June I to September 30, has been revised to verify that the average water temperature is within its limit at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> during the period from June I through September 30. The new temperature limit value of 100 degrees F has already been added to the ANO-1 TSs as discussed above, so its removal here just eliminates redundancy. Replacing "to" with "through" removes a possible point of confusion in that one could deterene that June 1 and September 30 are not included in the period requiring verification of the ECP's average temperature. Therefore, this change corrects a possible source of confusion, is consistent with the ANO-2 TSs, and is, therefore, acceptable.
The existing surveillance to make annual soundings of the ECP to ensus that the required volume' of water is available, has been revised to make annual soundings of the ECP and verify an average depth of 5 feet and a contained water volume within its limit. This change additionally requires that an average depth of 5 feet be verified, is consistent with the ANO-2 TSs, and is, therefore, acceptable.
An additional surveillance has been added to visually inspect the loose stone (riprap) placed on the banks of the pond and of the concrete slab spillway, and to verify that the earth portions of the stone covered embankments and the spillway have (1) not been eroded or undercut by wave action, and (2) do not show apparent changes in visual appearance or other abnormal degradation from their as-built condition. This change results in an additional limit in the ANO-1 TSs, is consistent with the AND-2 TSs, and is, therefore, acceptable.
The AND-1 ECP TS Bases have been revised to reflect the changes discussed above.
The staff finds that the proposed bases changes clarify the intent of the TSs and are, therefore, acceptable.
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. 1 2.2 Chanaes to ANO-2 TSs The surveillance that verifies the ECP's average water temperature, at least i
once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, during the period of June I through September 30, has been L
more precisely defined to specify the point at which the average water temperature is taken. The average water temperature is now specified to be i
taken at the discharge from the ECP.
In the July 28, 1993, application, the licensee states that the ECP analysis assumes the ECP is initially in a stagnant condition in which the solar gain, wind speed, and thermal current effects throughout the ECP are essentially at equilibrium, and, therefore, the average temperature at the point of discharge from the pond is representative of the thermal conditions assumed to exist in the ECP analysis. During a phone call with the licensee on November 3,1993, the staff requested the licensee to clarify the point that the average temperature at the point of discharge is representative of the thermal conditions assumed in the ECP analysis. The licensee provided the following clarification.
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Following a change in meteorological conditions, the bulk of the ECP requires approximately 3 days to reach equilibrium. The edges and surface of the ECP respond first, with the bulk of the ECP responding at a slower rate. As the ECP temperature is mearured by detectors mounted in the discharge from the ECP (suction of the service water system), which is located near the edge of the ECP, a change in meteorological conditions resulting in an increase in ECP temperature would be conservatively noted by the temperature detectors prior to the bulk of the ECP reaching equilibrium temperature. ANO conservatively assumes that the bulk temperature of the ECP is equal to the temperature i
detected near the edge of the ECP at the point of discharge from the ECP.
Therefore, assurance is given that on an ECP temperature increase caused by meteorological conditions, the required TS actions would be taken prior.to the bulk temperature of the ECP reaching the TS temperature value, preserving the analysis assumptions.
Based on the above, the staff finds that the proposed change is.an appropriate I
and conservative reflection of applicable analysis, is consistent with the ANO-1 TSs, and is, therefore, acceptable.
The ANO-2 ECP Bases have been revised to reflect the change discussed above and provide additional clarification. The staff finds that the proposed bases changes clarify the intent of the TSs and are, therefore, acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Arkansas State official was notified of the proposed issuance of the amendment. The State official i
had no comment.
4.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to installation or use of a facility omponent located within the restricted area as defined in 10 CFR Part 20 and change surveillance requirements. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no a
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> significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a pro-posed finding that the amendments involve no significant hazards consideration and there has been no public comment on such finding (58 FR 46228).
Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
T. Alexion, PD IV-1 Date: November 24, 1993 4
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