ML20247A554
| ML20247A554 | |
| Person / Time | |
|---|---|
| Site: | Vallecitos Nuclear Center |
| Issue date: | 12/31/1988 |
| From: | Cunningham G, Danni Smith GENERAL ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 8903290140 | |
| Download: ML20247A554 (8) | |
Text
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GENERAL ELECTRIC NUCLEAR TEST REACTOR ANNUAL REPORT NO. 29 I
l LICENSE R-33 1
DOCKET 50-73 l
NUCLEAP. OPERATIONS e GENERAL ELECTRIC COMPANY VALLECITOS NUCLEAR CENTER, PLEASANTON, CALIFORNIA 94566 gg32}ghi$ $$o$$ {3 g
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GENERAL ELECTRIC NUCLEAR TEST REACTOR.
ANNUAL REPORT NO.'.29.
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I.
INTRODUCTION This report summarizes the operation, changes,' tests, experiments, and major maintenance at the Nuclear Test Reactor (NTR) which were authorized-pursuant to License R-33 and 10CFR50, Section 50.59, for the period January-1,1988,
through December 31, 1988.
II.
GENERAL A.
The reactor was operated at or above. critical for.1,166.1 hours1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />; 362 start.ups were made. There were seven scrams during this report period. Total plant operation equaled 4.435 MW days in 1988.
B.
The average radiation exposure to facility personnel.was 3.03 Rem.
C.
There were no occurrences during 1988 that required notification of the NRC.
D.
There was one citation (Severity Level IV) issued as the~ result'of an NRC i
inspection.
III.
ORGANIZATION' There were no organizational changes in 1988.
f IV.
CHANGES, TESTS, AND EXPERIMENTS APPROVED BY.THE FACILITY MANAGER 1
A.
Channes i
Pursuant to 10CFR50.59(a), the Facility Manager. authorized the following changes in 1988.
u 1.
South cell Shieldine Addition
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Description:==
Additional shielding for gamma and neutron radiations was added to the South Cell.
Two equipment vacuum pumps.also were.
l relocated for better accessibility.
Safety Ansivsis: This change will'not impact the safe operation of the NTR and does not require a change.in the~ reactor license or Tech Specs. Additional ceiling loading was. analyzed and approved, d
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m NTR Annual Report No. 29 A.
Chanres (Continued) 2.
Backflow Prevention Chances
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Description:==
Backflow prevention devices that protect the potable j
water supply were replaced by newer units.
Safety Analysis:
Plumbing removed from radiation areas was treated as radioactive waste. Cutting and burning permits were utilized during welding and soldering operations.
3.
ANA Irradiation Facility rb
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Description:==
This change authorized removal of an obsolete cluster I
of small tubes that provided an experiment insertion guide from the North Room to an experiment tube in the reactor and replaced it with a larger single tube.
I Safety Analysis: There will be no change in reactivity effects as the guide is external to the graphite reflector. No loose parts exist which could conceivably interfere with control or safety rod' I
movement.
Potential personnel dose rates were evaluated to be within_
l acceptable limits.
4.
Safety Rod Sprines
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Description:==
This CA authorized the use of AISI-1095 heat-treated RC l
48-51 steel for safety rod scram springs and the use of 301 stainless l
steel for the safety rod spring leaders.
Safety Analysis: The new material is considered to be superior to the old material. Only one set of safety rod springs will be replaced and tested at a time.
New spring tension criteria may be established by an approved procedure revision if necessary.
Scram times will be kept within limits.
j 5.
Stack Recorder l
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Description:==
This change authorized replacement of the old stack gas and particulate recorder.
Safety Analysis: There are no unreviewed safety questions.
The new recorder was calibrated and tested prior to acceptance.
B.
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Pursuant to 10CFR50.59(a), there were no special tests performed during 1988 which required the approval of the Facility Manager.
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\\
. NTR Annual Raport No. 29 C.
Experiments There were 1,428 individual experiments reviewed, approved, and performed
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in 1988.
Five experiment type approvals were reviewed and approved.
All were for irradiations. These'are discussed below.
1.
Mercury Oxide Irradiation Samples of a stable oxide of mercury were approved for irradiation.
Safety Analysis: The NTR irradiation may be performed safely using existing tools and-procedures.
Predicted radiation exposure for handling irradiated samples was within allowable limits. The conse-quences of credible failures _were determined to be inconsequential.
l 2.
Zine Wire Irradiation l
Irradiation of zine wire was authorized.
l Safety Analysis: The NTR irradiation _may be performed safely using existing tools and procedures.
Predicted radiation exposure for handling irradiated samples was within allowable limits. The conse-quences of credible failures were determined to be inconsequential.
3.
Flex Cable Irradiation l
This experiment involved irradiation of a small section of flex cable planned to be used to insert and remove experiments in the facility discussed in Change No. 3 (Section'IV.A.3.) to verify-that the radioactivity from activation was acceptable.
Safety Analysis: Reactivity and radioactivity effects were calculated and determined to be acceptable prior to the irradiation.
4.
Deoleted Uranium Irradiation The irradiation of depleted U-238 samples to produce 150 pCi of Np-239 was authorized.
Sa fe ty Analysis: The NTR irradiation may_be performed safely using existing tools and procedures. Predicted radiation exposure for handling irradiated samples was'within allowable limits. The conse-l
{_
quences of credible failures were determined to be inconsequential.
5.
Routine Irradiations This change authorized the irradiation of routine samples in the
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irradiation facility described in Change No '3 (Section IV.A.3.).
Safety' Analysis:
Of five potential hazards. identified in the original CA for ANA irradiations, three are reduced and two were addressed by minor procedure changes governing handling. The reactivity effects were predicted and verified to be insignificant.
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m NTR Annual Rsport No. 29 V.
MAJOR PREVENTIVE OR CORRECTIVE MAINTENANCE A.
The primary pump and motor were replaced with identical spares.
This work required one day of nonoperation.
B.
The motor and coupling for the facility stack and .r sampling systems were replaced with identical spares.
The change was scheduled so that there was no interruption of reactor operation.
VI.
UNSCHEDULED SHUTDOWNS i
There were six (6) screas and one manual rundown during this report period:
A.
A picoammeter trip occurred moments after reaching full power.
B.
A manual shutdown was made when the operator felt an earthquake.
C.
Momentary utility power loss caused one scram.
D.
Loss of flow scram occurred due to pump seal failure.
E.
Operator switching errors on picoammeters caused three shutdowns.
Recovery was made in a matter of minutes on all shutdowns except the pump failure.
(One day was required to obtain and install the new pump and motor.)
VII.
RADIATION LEVELS AND SAMPLE RESULTS AT ON-AND OFF-SITE MONITORING STATIONS The data below are from sample and dosimeter results accumulated during 1988.
Except for the NTR stack data, these data are for the entire VNC site and include the effects of operations other than the NTR.
A.
NTR Stack Total airborne releases (stack emissions) for 1988 are as follows.
Alpha Particulate, < 0.18 C1 (predominantly radon-thoron daughter products)
Beta-Gamma Particulate, < 1.09 pCi Iodine-131, < 18.9 pC1 Noble Gases, 2.71 x 102 Ci Noble gas activities recorded from the NTR stack integrate background readings with the actual releases which may account for 40 to 50% of the activity released.
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. NTR Annual Rsport No. 29 B.
Air Monitors (Yearly average of all meteorological stations.)
Four environmental air monitoring stations are positioned approximately 90 degrees apart around the operating facilities of the site.
Each station I
is equipped with a membrane filter which is changed weekly and analyzed for gross alpha and gross beta-gamma.
k Alpha Concentration:
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-15 Maximum
< 4.8 x.10 Ci/cc (predominantly rar'n-thoron i
-15 Average
< 2.73.x 10 pCi/cc Beta Concentration:
<9.4x10'f4pCi/cc Maximum Average
< 2.69 x 10 pCi/cc C.
Gamma Radiation I
The yearly dose results for the year 1988 as determined from evaluation of site perimeter TLD environmental monitoring dosimeters showed normal background.
D.
Venetation No alpha, beta or gamma activity attributable to activities at the NTR-facility was found on or in vegetation in the vicinity of the site.
i E.
Water i
There was no release of radioactivity in water or to the ground water greater than those limits specified in 10CFR20, Appendix B, Table II, Column 2.
F.
Off-Site l
1 Samples taken off the site indicate normal background for the area.
VIII.
RADIATION EXPOSURE i
The highest annual dose to NTR Operations personnel was 3,755 mrem, and the lowest was 1,555 mrem.
The average dose was 3,034 mrem per person.
For contractor personnel working at NTR, the average dose was 1,312' mrem (maximum: 2,485 mrem; minimum: 597 mrem).
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. NTR Annual Raport No. 29 IX.
CONCLUSIONS The overall operating experience of the Nuclear Test Reactor reflects another year of safe and efficient operations. There were no reportable events.
Updated equipment and procedures should provide increased reliability in the ensuing years.
CENERAL ELECTRIC COMPANY Irradiation Processing A. A By D. R. Smith, Manager Nuclear Test Reactor 1
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GE Nuclear Energy Generet Elettnc Cornpany Ls!!ecaos Nuclear Center PO Bw 460. Valleutos (Md Prasanton. [A 94M6 l'
March 23, 1989 U. S. Nuclear Regulatory Commission Washington, D.C.
20555 Attention:
Document Control Desk
Reference:
License R-33, Docket 50-73 1
Gentlemen:
Enclosed are three signed copies of Annual Report.No. 29 for the General Electric Nuclear Test' Reactor.
Sincerely, h[
1 G. E. Cun ingham Senior Licensing Engineer (415) 862-4330
/ca Enclosures l
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