ML17278A319
| ML17278A319 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 07/18/1985 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17278A318 | List: |
| References | |
| TAC-57547, NUDOCS 8508060413 | |
| Download: ML17278A319 (3) | |
Text
+CP
'go~ 4~our Vp0 I
n C
O IOl 4'
g~ ~
0 Cp
+a*++
UNITEDSTATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION AMENDMENT NO.
15 TO NPF-21 MPPSS NUCLEAR PROJECT N0.2 DOCKET NO. 50-397 INTRODUCTION By letter dated April 19, 1985, the Mashington Public Power Supply System proposed certain changes to section 4'.6.1.7 of the Technical specifications for MNP-2.
.The proposed change resulted from a, design change of,the drywell cooling system (a non-safety system) that was implemented during a previous outage.
This change provided an improved air flow pattern resulting in reduced temperature gradients in the drywell.
EVALUATION Specifically, the licensee requested a change to Surveillance Requirement 4.6.1.7 which identified the thermocouple locations used to determine the drywell average air temperature.
The proposed change in Technical Specifications Surveillance Requirement 4.6.1.7 changes the elevation and azimuth location of the thermocouples as originally specified to inlet locations of the air coolers.
To improve the temperature profile in the drywell, the licensee modified the air flow patterns of the drywell. unit coolers.
This modification was accomplished by ducting the hot air in the annulus region, between the reactor pressure vessel and the sacrificial shield wall, through the unit coolers located in the lower portion of the drywell, rather. than the upper portion in the original design.
Had the licensee used the same thermocouples specified in Surveillance Requirement 4.6.1.7, the resulting drywell average temperature would be greater than the expected drywell average temperature due to the impingement of the annulus hot air on the thermocouples.
Therefore, the licensee proposed thermocouple locations at the inlet of the unit coolers where the inlet air temperature would be more representative for determining the drywell average temperature.
The licensee indicated that the temperature readings from the new thermocouple locations are neither influenced by the annulus hot air or the drywell unit cooler discharged air and, therefore, will yield more representative values for computing the bulk average drywell air temperature.
85080604i3 8507i8 PDR
'ADOCK 05000397 P
~ 'V Based'n our assessment of the proposed Technical Specifications
- change, we find that the original intent of the Limiting Condition for Operation is maintained.
The licensee has determined that'his change has little safety significance and that the proposed amendment will not alter any of the accident analyses.
The staff has reviewed these determinations and the associated change and concludes that they are acceptable.
ENVIRONMENTAL CONSIDERATION e
I
~c I
This amendment involves a change to the requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20.
The staff has determined that the-amendment involves no significant change in the types or significant increase in the amounts 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 proposed finding that this amendment involves no significant. hazards consideration and there has been no public convent on such finding.
Accordingly,, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9).
Pursuant to 10 CFR 51.22(b),
no environmental'mpact statement or ehvironmental assessment need be prepared in connection with,the issuance of this amendment.
,'ONCLUSION Me have concluded, based on the considerations discussed above, that:
(1)
', there is reasonable assurance that. the health and safety of the public will Inot be endangered by operation.in the; proposed manner;,
and (2) such activities
> will be conducted in compliance with the Commission's regulations and the
- ,issuance of this amendment wi;ll not, be inimical to the colon defense and
/
security or to the health aod. safety of the public.
I pate~d.
JUL 18 l885 l
l Prlnclpail Contributor:
F. El'tawila J
-.a
e C
1