IR 05000409/1981005
| ML19347F557 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 04/08/1981 |
| From: | Hopkins J, Jackiw I, Robinson D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML19347F556 | List: |
| References | |
| 50-409-81-05, 50-409-81-5, NUDOCS 8105200049 | |
| Download: ML19347F557 (5) | |
Text
.
s
U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT
REGION III
Report No. 50-409/81-05 Docket No. 50-409 License No. DPR-45 Licensee: Dairyland Power Cooperative 2614 East Avenue - South La Crosse, WI 54601 Facility Name:
La Crosse Boiling Water Reactor Inspection At:
La Crosse Boiling Kater Reactor Site, Genoa, WI Inspection C du d: March 23-24, 1981 k
WM Inspectors: D L.
obinson
$-E-6I y
B in'
f [' P/
//
I. N. Jackiw
,
/
~
Je/u s:
Approved by:' IV. Jac iw, Acting Chief, f- [- [/
Test Pr ram Section Inspection Summary j
Inspection on March 23-24, 1981 (Report No. 50-409/81-05)
Areas Inspected: Routine, unannounced inspection of the Cycle 7 Startup Physics Tests including control rod drive scram time tests; control rod sequence and reactivity checks; core power distribution limits; core thermal power evaluation; reactor shutdown margin determination; and reactivity anomaly determination. The inspection involved 18 inspecto;-
hours onsite by three NRC inspectors including 0 inspector-hours onsite during offshifts.
Results: No items of noncompliance or deviations were identified.
81052000 99
-
..
-
.
.
-
.
-
.
.
.
.
DETAILS 1.
Persons Contacted R. Shimshak, Plant Superintandent.
S. Raffety, Reactor Engineer
- G. Boyd, Operations Supervisor
- H. Towsley, QA Supervisor B. Zibung, Health and Safety Supervisor W. Nowicki, Instrumentation and Electrical Supervisor J. Gallaher, Shift Supervisor
- L. Goodman, Operations Engineer
- Denotes those present during the exit interview.
2.
Verification of Conduct of Startup Physics Testing The inspectors reviewed the startup physics testing and verified that the licensee conducted the following:
Control Rod Scram Time Tests
,
b.
Control Rod Sequence and Reactivity Checks c.
Core Power Distribution Limits d.
Core Thermal Power Evaluation e.
Determination of Shutdown Margin f.
ination of Reactivity Anomalies e
3.
Control Rod Scram Time Tests The inspectors reviewed the results of the control rod scram time tests performed on January 22, 1981, and concluded that the total l
scram time of each control rod as measured by the rod scram timer j
was less than 3.0 seconds as required by Technical Specifications.
l The inspectors verified that the rod scram timer had been calibrated in December 1980, prior te the above tests.
l No items of noncompliance or deviations were identified.
l
!
4.
Control Rod Sequence and Reactivity Checks l
l l
The inspector reviewed information relating to Cycle 7 control rod sequence and reactivity checks as described in Procedure No. 6 of Facility Change FC-31-80-1.
The inspectors noted that the computer code (TRILUX) was utilized for predicting control rod sequer.ce, evaluating the reactivity worth of each withdrawal step in a control rod sequence, and estimating the most conservative step worth.
l
!
-2-
!
.
_ - -
-
.
.
.-
__
_
_
.
.
The inspectors reviewed the results of tests performed on January 11, 1981, as described in FC-31-80-1.
The results indicated that there was a small discrepancy of 0.297% or reactivity between the predicted and the actual critical configuration. The inspectors noted that the test :esults satisfied the 2% of reactivity discrepancy as stated in the Technical Specifications.
No items of noncompliance or deviations were identified.
5.
Core Power,Distributicn Limits
.
The inspectors reviewed information relating to surveillauce of core thermal power distribution limits which were calculated by the computer cede (TRILUX). The inspectors examined the TRILUX p;intouts obtained in January and February,1981, and determined tha' all prerequisites v3re met, the computer was using input values from the cetual plant conditions, all thermal margins satisfied Technical Specification requirements, and the calculated val'ies by the computer were within the acceptable criteria established by the licen.ae.
No items of noncompliance or deviations were identified.
6.
Core Thermal Power Evaluatio_n LACBWR Technical Specifications require that core thermal power be evaluated every month. The inspectors noted that the evaluation was done an a week :-r basis.
The inspectors examined information relating to the March 23, 1981, calculations of core thermal power.
The calculations consisted Of a long form for an accurate primary heat balance and a chort form for an approximate heat balance. The inspectors reviewed the relevant flow diagram to ensure that all flow paths were properly accounted for in the long form. The inspectors performed a balance of masn flow rates to verify the mass flow rates used in the calcu-lations. The inspectors performed heat balances using the licensee's equations and verified that the percentages of full thermal po' er calculated in the long form and in the short form were 85.6% and 85.4% respectively.
The inspectors compared the power calculated from the heat balance with that indicated by the nuclear instrumentation and noted that the indicated power was less conservative but well within the 5%
acceptance criterion established by the licensee.
The inspectors reviewed the calibration of the automatic gain control system (AGCS) for the nuclear instrumentation providing the indicated power. The inspectors noted that the AGCS was calibrated on March 5, 1981 and that Channel 8, which had been indicating low was adjusted-3-
-..
.
-
_.. -
-
-
-
..
.
.
._
.
e at that time. The licensee was operating the vtant at 85% rated power due to the noise level in the nuclear instrumentation.
No items of noncomp11ance or Jeviations were identified.
7,.
Shutdown Margin Determination LACBWR Technical Specifications require that the rLutje.n margin with the most reactive control rod stuck out of the core be greater than 0.5% of reactivity.
The inspectors examined information relating to shutdown margin determination as described in Procedure No. 6 of Facility Change FC-31-80-1.
The inspectors noted that the calculated shutdown margin with the highest worth rod (Rod 29) out of the core was The calculatien was pe formed using TRILUX, a 4.6% reactivity.
fuel management computer program.
The inspectors examined the measurement data taken on January 11, 1981, to confirm that the required shutdown margin was available.
The reactor temperature was maintained at 88 F and all 29 control rods were sequentially withdrawn to 12.547 dial inches so that criticality was maintained. All rods except Rod 29 were further inserted to 10.48 dial inches and the reactor was determined to be suberitical by 1.28% of reactivity using the known worth of the 28 partially withdrawn rods. The inspectors cone.luded that the shutdown margin determination was adequate.
No items of noncompliance or deviaticus were identified.
8.
Reactivity Anomaly Deternsinr ion The inspectors reviewed infc2mation relating to Cycle 7 determination of reactivity anomaly. The Technical Specifications requivf that the reactivity anomaly be no greater than 0.6%.
The inspectors noted that the computer code (TRILUX) was used for calculations of keff. The inspectors further noted that the pre-dicted keff at the beginning of Cycle 7 was 1.014 as stated in LAC-TR-087, " Refueling Plan for Cycle 7 of LACBWR," dated October 1980. The inspectors reviewed the TRILUX printouts for February 1981, and noted that the keff for actual core conditions varied from 1.016 to 1.013.
The inspectors concluded that the determina-tion of reactivity anoaaly satisfied Technical Specification requirementr,.
No items of noncompliance or deviations were identified.
-4-
.
-
-
-
. _.
_._
-. -.
_
_
_
_. _.,
- _
._
i
- +
>
V
>
9.
Exit Interview
The irispectors met with licensee representatives (denoted in Para-
[v':
graph 1) at the conclusion of the inspection on March 24, 1981.
[.
The inspectors summarized the purpose and scope of the inspection and the findiegs,
<
i i
?
!
I t
s
1
!
l t
,
l
!
i
!
,
I
,
i i
t-5-