ML20044E057

Safety Evaluation Supporting Amend 107 to License NPF-29

ML20044E057
Person / Time
Site:	Grand Gulf
Issue date:	05/17/1993
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20044E048	List: ML20044E047 ML20044E057
References
NUDOCS 9305210228
Download: ML20044E057 (5)

Text

. _ _. ~. _ _ _.

pR Rf Cg, i

O k

UNITED STATES i

NUCLEAR REGULATORY COMMISSION

[ g.D M j

• g g

WASHINGTON. D.C. 20666-D001 gv

/

1 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR-REACTOR REGULATION j

RELATED TO AMENDMENT NO.107 TO FACILITY OPERATING LICENSE NO. NPF-29 i

l i

j ENTE'IGY OPERATIONS. INC.. ET AL.

j GRAND GULF NUCLEAR STATION. UNIT I

]

DOCKET NO. 50-416 i

i

1.0 INTRODUCTION

By letter dated February 26, 1993, Entergy Operations, Inc., (the licensee).

submitted a request for revision of the Grand Gulf Nuclear Station Unit 1 i

(Grand Gulf) Technical Specifications (TS). The revision would revise TS j

j 3/4.4.3, Leak Detection Systems, Surveillance Requirements 4.4.3.2.1 and the i

bases for each. The amendment would modify the TS consistent with the i

Improved Standard Technical. Specifications as presented in NUREG-1434, Rev. 0 l

in that the NUREG-1434 requirements are incorporated consistent with the existing TS format and conventions.

Specifically, the amendment provides

)

additional action statements consistent with the current design of the leakage detection systems and supports increased operational flexib..ity while l

preserving adequate monitoring of the reactor coolant pressure boundary.

2.0 BACKGROUND

i Currently, Specification 3.4.3.1. requires that the following Reactor Coolant-i j

System (RCS) leakage detection systems be operable:

i a.

The drywell atmosphere particulate radioactivity monitoring system.

l b.

The drywell floor and equipment drain sump level and flo.t monitor.w l

systems, and l

c.

Either the drywel'. air coolers condensate flow rate monitoring i

j system or the drywell Atmosphere gaseous radioactivity monitoring l

l system.

i The action statement for this limiting condition for operation-(LCO) states, in part, that with only two of the three RCS leakage detection systems j

operable, operation may continue for up to 30 days provided grab samples of the drywell atmosphere are taken and analyzed at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when 4

the required gaseous and/or particulate radiation monitoring system is 3

inoperable; otherwise, be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and. in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

l The proposed amendment to the TS requests changes to TS 3/4.4.3.1, the.

i surveillance and the TS bases for each. The proposed specification conforms l

to NUREG-1434 and provides for a 30-day period of continued operation with I

9305210228 930517

{DR ADOCK 05000416 PDR-i

O

• two of the three required RCS leakage detection systems inoperable provided that the Drywell Floor Drain Sump Monitoring System is operable.

I l

3.0 EVALUATION The Nuclear Regulatory Commission (NRC) staff review of the proposed amendment included assessments of the LCO for TS 3.4.3.1, Leak Detection Systems, Surveillance Requirements 4.4.3.2.1 and their bases.

j i

3.1 LCO for TS 3.4.3.1 The licensee proposes that the required leakage detection systems of this LCO be rearranged to provide for a 30-day out of service period to restore from a condition involving inoperability of both the drywell atmospheric monitor and i

the drywell condensate flow monitoring system. The arrangement and restate-l ment of the LC0 would provide consistency with the Improved Standard Technical Specifications as presented in NUREG-1434, Rev. O.

-l 1

The rearrangement would group the drywell atmospheric monitoring systems since f

they perform the similar function of providing continual monitoring of the 8

drywell atmosphere for radioactivity indicative of an RCS leak. Currently, TS 3.4.3.1 and 4.4.3.1.b require that both the drywell floor and equipment drain sump level and flow monitoring systems be operable. The licensee is proposing l

l to eliminate the requirement to include the equipment drain monitoring system.

The equipment drain monitoring system monitors identified leakage from j

specifically identified leakage sources within the drywell and is subject to its own LCO of 30 gpm in T.S. 3/4.4.3.2.

)

i The remaining system in the proposed TS, the drywell floor drain sump monitoring system, is used to quantify and/or recognize unidentified leakage in the drywell.

The revised TS will not result in a reduction in the margin of safety and the staff finds the changes acceptable.

3.2 Action Statements for TS 3.4.3.1 l

l The licensee proposes additional action statements consistent with the design l

l of the current leakage detection system and support increased operational l

flexibility while preserving adequate monitoring of the reactor coolant l

pressure boundary.

f Action A The drywell floor drain sump monitoring system is used to quantify i

unidentified leakage in conjunction with Specification 3/4.4.3.2. With the system inoperable, RCS unidentified and total leakage are determined every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> per TS 4.4.3.2.1 to ensure adequate monitoring of the reactor coolant pressure boundary. This meets the requirements of Generic Letter (GL) 88-01, i

l r

Supplement 1, "NRC Position on Intergranular Stress Corrosion Cracking (IGSCC) 1 In BWR Austenitic Stainless Steel Piping." The GL acknowledges that leakage can be quantitatively measured by alternative methods such as manually pumping the sump or measuring the differences in sump level during the period (30 days) that the drain sump monitoring system is being restored, provided the licensee demonstrates their suitability with regard to accuracy and inspectability. The 30-day completion time is bas d on other leakage detection systems being operable.

TS 3.0.4, which prevents mode changes unless the conditions of the LC0 are met without reliance on provisions contained in the action statement, is not applicable since other methods are available to monitor RCS leakage.

j l

The revised TS assures that unidentified leakage within the drywell is promptly identified and is acceptable to the staff.

Action B The drywell atmospheric monitoring system provides continuous monitoring of the drywell gaseous and drywell particulate atmosphere. With the drywell atmosphere monitoring system inoperable, grab samples of the drywell atmosphere are taken and analyzed at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

Grand Gulf's proposed action statement conforms to the standard TS action statement for l

BWR-6 plants that require the drywell air cooler condensate flow monitor to be l

operable.

l The proposed changes meet the staff's requirements stated in GL 88-01 and is l

acceptable to the staff.

Action C The drywell air cooler condensate flow rate monitoring system serves as an indicator, but not quantifier of RCS unidentified leakage by monitoring the condensate flow from four of the six drywell coolers.

If the system is inoperable a Channel Check is performed on the required drywell atmospheric monitoring system once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 8-hour interval provides periodic l

information of activity in the drywell.

Systems for detecting and quantifying RCS leakage remain operable.

This action statement has been modified by a note that allows this action to not be applicable if the required drywell atmospheric monitoring system is 1

inoperable. This conforms with TS 4.0.3, which states, in part, that i

surveillance is not required to be performed on inoperable equipment.

The staff has evaluated the condition in which the drywell air cooler condensate flow rate monitoring system is inoperable, and concluded that channel checks once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> are acceptable in providing information of the activity in the drywell.

l

=

[

J j

i ;

t 1

Action D w

With both the atmospheric radioactivity monitoring system and the drywell air cooler condensate flow monitoring system inoperable, the only means of i

4 detecting unidentified leakage is the drywell floor drain sump monitoring system. This condition does not provide diversity in detecting unidentified leakage. Therefore. a 30-day time requirement is imposed to prevent extended operation while in this degraded configuration. The 30-day time limit allows i

time to restore the atmospheric radioactivity monitoring system or the drywell l

air cooler condensate flow monitoring systera to operability. The required t

action is modified by a Note that states the provisions of 3.0.4 are not applicable since other instrumentation is available to monitor RCS leakage t

during mode changes.

l 4

To ensure restoration of diversity, operation with both the atmospheric radiation monitoring and the drywell air cooler condensate flow monitoring i

systems inoperable will be limited to 30 days.. The staff has evaluated this l

condition in which both the atmospheric radioactivity monitoring system and i

the drywell air cooler condensate monitoring system are inoperable, and determined that the 30-day time requirement to restore either to an operable status is acceptable.

Action E and F l

If any of the above required actions cannot be met within the required completion time the plant must be brought to HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and to COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

With all required monitoring systems inoperable, the plant will enter ~ LC0 3.0.3 within one hour.

LCO 3.0.3 states that when an LCO is not met, except in the associated action requirement, within one hour action shall be initiated to place the unit in hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, in HOT l

SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in COLD SHUTDOWN within the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

s The staff has evaluated the requirement to shutdown if the time requirements are not met or if all RCS leakage detection systems are inoperable. The staff l

concluded that these are appropriate actions. The staff also finds that these actions acceptable to ensure public health and safety.

j a

3.3 Surveillance 4.4.3.2.1 i

4 The current Surveillance 4.4.3.2.1, specifically identifies the systems that are monitored to demonstrate that the Reactor Coolant System Operational Leakage Limits are not exceeded.

This proposed change to Surveillance 4.4.3.2.1 deletes references to these specific systems used to demonstrate that the reactor coolant system leakage l

is within limits.

L

_q_

RCS leakage is monitored by systems to quantify unidentified and identified leakage. Operability of the equipment necessary to monitor unidentified leakage is governed by LC0 3.4.3.1.

The quantification of leakage is performed by the drywell floor sump monitoring system.

The staff evaluated the licensee's proposed change to surveillance 4.4.3.2.1 requirement and concluded that performance of the surveillance is not required to verify that the leakage rate requirements are satisfied.

The staff finds the proposed change of omitting references to specific systems used to perform the surveillance is acceptable.

3.4 Bases The bases for 3/4.4.3.1, Leakage Detection System, and 3/4.4.3.2, Operational I

Leakage, were expanded to reflect the above changes.

To provide consistency with T.S. 3/4.4.3.1 and 3/4.4.3.2, the staff concluded that expanding the bases to reflect the changes in these specifications is acceptable.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Mississippi State i

official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative i

occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (58 FR 19477). Accordingly, the amendment meets 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 amendment.

6.0 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 amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor:

V. Gaddy Date:

May 17, 1993