ML20009H101
| ML20009H101 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/31/1981 |
| From: | Wade W EG&G, INC. |
| To: | |
| Shared Package | |
| ML20009H099 | List: |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.E.4.2, TASK-TM SRO-258, NUDOCS 8108060012 | |
| Download: ML20009H101 (2) | |
Text
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9 Assaa Energy Measurements Group san namon o eration.
SRO-258 r
liay 1981 f
J E
4 TECHNICAL EVALUATION OF THE RESPONSE TO POSITION NO.5 OF ITEM II. E. 4.2 O'i NUREG-0737 CONTAINMENT ISOLATION SETPOINT i
FOR THE 4
MILLSiONE i
NUCLEAR POWER PLANT 1
UNITS 1 AND 2 j
(DOCKET Nos. 50-245 and 50 336) by W. O. Wade Approved for Puolication
/</ l k.~
W. R. Ruvalcaca Department Manager i
i j
This document is UNCLASSIFIED t
i
</
ss ier:
'Nicnolas y/ drocericK Department Manager l
l Work Performed for Lawrence Livermore Nat! anal Laboratory under U.S. Department of Energy Contract No. DE.ACO S-76 NVQ 1183.
8108060012 810720 i
fDRADOCK 05000245 i
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M INTRODUCTION AND BACKGROUND As a cons,equence of the incident at TMI-2, implementation of a number of new requirements nas been recomended for operating reactors.
~
These new requirements are described in NUREG-0660, "NRC Action Plan Devel-oped as a Result of the TMI-2 Accident," May 1980, and NUREG-0737, "Clari-fication of TMI Action Plan Requirements," Novemoer 1980.
Tne NRC staff nas also requested licensees to submit information sufficient to permit an independent evaluation of their response to tnese new requirements.
Tnis 4
j report provides an evaluation of the response to Action Plan Item II.E.4.2,
]
position 5, by tne designated licensee.
2 DESIGN BASIS OR REVIEW CRITERIA
}
Position 5 requires tnat tne containment pressure setpoint tnat 1
initiates containment isolation for non-essential system containment vessel penetrations be at, or reduced to, "...tne minimum compatible with normal J
operating conditions."
TECHNICAL EVALUATION
/
Response evaluation is based upon the values provided for the following parameters:
(1)
Tne maximum observed or expected containment pressure
]
during normal operatior..,
I (2)
The loop error and observed drift in tne pressure j
sensing instrun.entation providing tne isolation signal j
(see note).
1 (3)
The et-tainment isolaticn pressure setpoint.
\\
l.
NOTE: The ' clarification document (NUREG-0737) provided only i
the expected margin for instrument error and did not specify acceptable values for instrument drift or j
atmospneric cnanges contributing to tne total sensing j
loop error.
Additional staff guidance estaolisned a limit of 3.0 psi for an isolation setpoint margin over the normal containment pressure to account for total i
loop error.
In addition, for subatmospneric contain-2 ments, a 3.0 psi setpoint margin over atmospneric pressure is also considered acceptable.
t In consideration of these values, the isolatira pressure setpoint_.
j is to be as low as practical witnout increasing tne probwility of inadver-j tent activation of the isolation signal.
CONCLUSIONS 1
i The letters of December 31, 1980 and Feoruary 27, 1981, submitted by Nortnesst Nuclear Energy Company, provided sufficient information to l
conclude that the containment isolation pressure setpoint for Millstone Nuclear Power Plant, Units 1 and 2,. mets the NUREG-0660/0731 requirements and is witnin the additional limiting guidelines provided by tne NRC staff.
i i
k
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