ML19256G076
| ML19256G076 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 12/20/1979 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0578, RTR-NUREG-578 LAC-6706, NUDOCS 7912270388 | |
| Download: ML19256G076 (3) | |
Text
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Il.tIIt YLA.YIB I*0 WEll COUI* Eft.t TIVE fa Crow, 0)homin 54601 December 20, 1979 In reply, please refer to LAC-6706 DOCKET NO. 50-409 U.
S.
Nuclear Regulatory Commission ATTN:
Mr. Harold R.
Denton, Director Office of Nuclear Reactor Regulation Washington, D.
C.
20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER RE7CTOR (LACBWR)
PROVISIONAL OPERATING LICEL2E NO. DPR-45 THREE-MILE ISLAND LESSONS LEARNED -
SHORT TERM REQUIREMENTS
Reference:
(1)
DPC Letter (LAC-6680), Linder to Denton, dated December 6, 1979.
Gentlemen:
In response to your request for justification for differing frcr the Staff's "short tern" requirements resulting from the NRC staff investigations of the TMI accident, we presented our responses to the various items (Reference 1).
The items which you indicate require further clarification er a change in our previous position are presented to supplement our earlier response.
Item 2.1.8.c - Improved In-Plant Iodine Instrurentation Under Accident Conditions LACBWR presently has the capability to sar.ple for icdine both within and outside the plant and to analyze samplirl cartridges in the hot lab.
In the case of high radiation in the lab (up to 15 R/hr from MCA according to SAR), the analytical equipment is transferrable to a low background area if entry into the plant is possible.
Facilities capable of analyzing sampling cartridges are also available at the University of Wisconsin, La Crosse campus, 17 miles from the plant.
Additional equipment is being ordered so that the lab located in the Administration Building and both assembly points will also possess this capability.
1643 157 39$
7912270
Mr. Harold R.
Denton, Director LAC-6706 Of fice of Nuclear Reactor Regulation December 20, 1979 Item 2.1.9 - Transient Analysis The results of small break LOCA analysis review are being submitted concurrently in our letter LAC-6705.
Procedural change and training requirements originating from this review will be completed by January 1, 1980.
The results of inadequate core cooling ar.alysic will be submitted during January 1980.
Preliminary results using conservative assurp-tions have been used to derive a thne for operator response in reccg-nizing loss of adequate core cooling through inoperability of the lugh pressure safety system.
This time along with guidelines for recog-nizing inadequate core cooling will be the subject of procedure modification and operator retraining by January 1, 1980.
A meeting with the NRC staff to clarify the scope of the accident and transients analysis will be scheduled in January 1980 with ccmpletion of this analysis and implementation of required retraining resulting from the analysis to be scheduled at that time.
Item 2.1. 2 - Relief and Safety Valve Testino DPC commits to participate in the EWR Owners Group evaluatien and verification of the operability of pressure relieving main steam safety valves.
The conclusions arising frca the Cuners Grcup ezal-uation of BWR safety valve operation under single-phase and two-phase flow conditions will be factored into the overpressurinatien analyses as they apply to the LACBWR facility.
Item 2.1.3.a - Direct Indication of Valve Positien The La Crosse Boiling Water Reactor will continue to maintain its existing temperature indiceting syster as an indication of relief valve opening.
We will install switches as soon as equipment can be procured and a reactor refueling shutdown commenced to permit installation.
The refueling outage is currently scheduled to commence during February 1980.
Seven-conductor mineral insulated cable is available onsite.
available during January 1980 and qualified junction Switches are boxes and two-conductor MI cables will be secured on an accelerated basis.
Item 2.1.3.6 - Inadequate Core Cooling The best indicaticn for inadequate core cooling at the LACBWR plant is reactor water level.
The depth of diversity in reactor water level is outlined in LAC-6262, dated May 2, 1979 (Pages 5 - 7) -
six transmitters are provided.
The water level indication at LACEWR 1643 158
Mr. Harold R.
Denton, Director LAC-6706 Office of Nuclear Reactor Regulation December 20, 1979 was modified in 1976 to meet the single-failure criteria during ECCS qualification to the Interim Acceptance Criteria.
The basis of acceptability of the ECCS systems and their initiators (i.e.,
water level instrumentation) to function in all conditions and environments, including a design basis loss of coolant event are documented in LAC-4082, dated July 21, 1976.
The reactor water level is an unambiguous method of determining adequate core cooling.
Technical Specifications control any limitations on communication between the core annulus (where water level signals tap off) and the fueled region.
The LACBWR design provides adequate core cooling if water level is above the top of the fuel or if the high pressure core spray system is operating.
This second method of determining adequacy of core cooling is indicated directly in the Control Room by high pressure core spray or alternate core spray operating indicators.
Gulf United Fuel Report SS-942, dated 5/31/72, states that even if core coverage cannot be maintained, operation of the emergency core cooling systens will be adequate to provide core cooling and preclude fuel damage.
The emergency core cooling systems are designed to function under all conditions, including a design basis loss of coolant event.
It is our conclusion that existing instrumentation (i.e.,
water level and ECCS operational indication) are the best indicators of inadequate core cooling that can be developed for this facility.
In both cases they have redundancy and are environ-mentally qualified.
If you have any questions, please contact us.
Very truly yours, DAIRYLAND POWER COOPERATIVE Ades]
'H' Frank Linder, General Manager PL:JDP:af cc:
J.
Keppler, Reg. Dir., NRC-DRO III 1643 159 3-