ML20207M478
| ML20207M478 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 01/05/1987 |
| From: | NORTHEAST NUCLEAR ENERGY CO. |
| To: | |
| Shared Package | |
| ML20207M473 | List: |
| References | |
| NUDOCS 8701130189 | |
| Download: ML20207M478 (3) | |
Text
!
l Docket No. 50-423 j
B12359 i
I 1
Attachment I l
i Millstone Nuclear Power Station, Unit No. 3 Proposed Revision to Technical Specifications l
t l
l Q11hM{
5 January 1987 P
L
REACTOR COOLANT SYSTEM HOT SHUTDOWN LIMITING CONDITION FOR OPERATION 3.4.1.3 At least two of the reactor coolant loops listed below shall be OPERABLE, with at least two reactor coolant loops in operation when the Reactor Trip Systern breakers are closed. At least two of the loops listed below shall be OPERABLE and at least one of these loops shall be in operation with the Reactor Trip System breakers opent*
a.
Reactor Coolant Loop 1 and its associated steam generator and reactor coolant pump,*
- b.
Reactor Coolant Loop 2 and its associated steam generator and reactor coolant pump,*
- c.
Reactor Coolant Loop 3 and its associated steam generator and reactor coolant pump,*
- d.
Reactor Coolant Loop 4 and its associated steam generator and reactor coolant pump,*
- e.
RHR Loop 1, and f.
RilR Loop 2.
APPLICABILITY: MODE 4.
ACTION:
a.
With less than the above required loops OPERABLE, immediately initiate corrective action to return the required loops to OPERABLE status as soon as possibici !! the remaining OPERABLE loop is an RHR loop, be in COLD SHUTDOWN within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
b.
With no loop in operation, suspend a!! operations involving a reduction in boron concentration of the Reactor Coolant System and immediately initiate corrective action to return the required loop to operation.
All reactor coolant pumps and RilR pumps may be deenergized for up to I hour provided: (1) no operations are permitted that would cause dilution of the Reactor Coolant System boron concentration, and (2) core outlet temperature is maintained at ! cast 100F below saturation temperature.
" A reactor coolant pump shall not be started with one or more of the Reactor Coolant System cold leg temperatures less than or equal to 3500F unless the secondary water temperature of each steam generator is less than 500F above cach of the Reactor Coolant System cold leg temperatures.
MILLSTONE - UNIT 3 3/44-3 L
3/4.4 REACTOR COOLANT SYSTEN1 l
BASES The plant is designed to operate in MODES 1 and 2 with three or four reactor coolant loops in operation and maintain DNBR above 1.30 during ali normal operations and anticipated transients.
With less than the required reactor coolant loops in operation this specification requires that the plant be in at least' HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
In MODE 3 and 4, two reactor coolant loops provide sufficient heat removal capability for removing core decay heat even in the event of a bank withdrawal accident; however, a single reactor coolant loop provides sufficient heat removal capacity if a bank withdrawal accident can be prevented, i.e., by opening the Reactor Trip System breakers. Single failure considerations require that two loops be OPERABLE at all times.
In MODE 4, and in MODE 5 with reactor coolant loops filled, a single reactor coolant loop or RHR loop provides suf ficient heat removal capability for removing decay heat; but single failure considerations require that at least two loops (either RHR or RCS) be OPERABLE.
In MODE 5 with reactor coolant loops not filled, a single RHR loop provides sufficient heat removal capability for removing decay heat; but single failure considerations, and the unavailability of the steam generators as a heat removing component, require that at ! cast two RHR loops be OPERABLE.
The operation of one reactor coolant pump (RCP) or one RHR pump provides adequate flow to ensure mixing, prevent stratification and produce gradual reactivity changes during boron concentration reductions in the Reactor Coolant System. The reactivity change rate associated with boron reduction will, therefore, be within the capability of operator recognition and control.
The restrictions on starting an RCP with one or more RCS cold Icgs less than or equal to 3500F are provided to prevent RCS pressure transients, caused by energy additions from the Secondary Coolant System, which could exceed the limits of Appendix G to 10 CFR Part 50. The RCS will be protected against overpressure transients and will not exceed the limits of Appendix G by either:
(1) restricting the water volume in the pressurizer and thereby providing a volume for the reactor coolant to expand into, or (2) by restricting starting of the RCPs to when the secondary water temperature of each steam generator is less than 500F above each of the RCS cold leg temperatures.
The requirement to maintain the isolated loop stop valves shut with power remwed ensures that no reactivity addition to the core could occur due to the startup of an isolated loop. Verification of the boron concentration in an idle loop prior to opening the stop valves provides a reassurance of the adequacy of the boron concentration in the isolated loop. Draining and refilling the isolated loop within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to opening its stop valves ensures adequate mixing of the coolant in this loop and prevents any reactivity effects due to boron concentration stratifications.
MILLSTONE - UNIT 3 B 3/4 4-1
,