ML19282C850
| ML19282C850 | |
| Person / Time | |
|---|---|
| Site: | 07001113 |
| Issue date: | 04/06/1979 |
| From: | Gibson A, Troup G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML19282C847 | List: |
| References | |
| 70-1113-79-10, NUDOCS 7905070101 | |
| Download: ML19282C850 (3) | |
Text
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UNITED STATES natGu
[
jo NUCLEAR REGULATORY COMMISSION g
REGION il o
5 101 M ARIETTA STREET, N.W.
ATLANTA. GEORGI A 3o303 s.,...../
Report No.
70-1113/79-13 Licensee:
General Electric Company P. O. Box 780 Wilmington, North Carelina 28401 Facility Name: Wilmington Nuclear Fuel Plant Docket No.
70-1113 License No.
SNM-1097 Inspection at Wilmingt clear Fuel Plant 6
['t
/ d 7f Inspector:
' Date Signed G. L. Trdup \\/
l
[
/7 Approved b : A. F. Gibdon, Sectioh Chief, FF&MS Branch
~ Date Signed
SUMMARY
Inspection on March 20, 1979 Areas Inspected This special, announced inspection involved three inspector hours onsite concerning the determination of the site boundary concentrations due to an unplanned release on December 3,1978, including the source term, effective height of release, building wake effects and plume dispersion.
Results Of the four areas inspected, no apparent items of noncompliance or deviations were identified.
7905070lo(
i DETAILS 1.
Persons Contacted Licensee Employees
- A. L. Kaplan, Manager, Licensing and Compliance Audits J. H. Bradberry, Acting Emergency Preparedness Coordinator S. J. Mendendez, Nuclear Safety Engineer
- Attended exit interview.
2.
Exit Interview The inspection scope and findings were summarized on March 20, 1979, with those persons indicated in Paragraph 1 above. The inspector stated that the impact of his questions and comments on the site boundary concentration was unknown at the time of the inspection.
Mr. Kaplan stated that the source term would be reevaluated and the building and stack height effects considered in the reevaluation of the site boundary concentrations.
3.
Licensee Action on Previous Inspection Findings Not inspected.
4.
Unresolved Items Unresolved items were not identified during this inspection.
5.
Scope of Inspection ccurred.
On December 3, 1978, an incident involving the release of UF6 A report of the incident, including an assessment of offsite releases, was forwarded by a letter dated January 9,1979. As noted in RII Report No. 70-1113/79-6, paragraph 10.b, the licensee provided the inspector with a copy of meteorology data and release calculations for in-of fice review. The inspection was conducted to discuss questions raised by the inspector concerning the methodology used in the calculations and comments concerning the source te rm and ef fective stack heights in the plume dispersion calculations.
6.
Determination of Ef fluent Concentratioas a.
The licensee calculated the concentration of radioactivt material at the site boundary, using a source term based on the stack sampler results, an ef fective stack height determined from Holland's equation
e t for the effective height of emission and concentrations based on Pasquill's equation for atmospheric dispersion.
Based on the licensee's calculations, airborne concentrations at the site boun-dary were below the limits of 10 CFR 20, Appendix B, Table II, Column 1.
Calculations for the concentration at a point inside of the site boundary were also less than 10 CFR 20 concentration limits.
b.
The inspector reviewed the licensee's calculations and performed the calculations independently to evaluate the site-boundary concen-trations.
In evaluating the licensee's calculations the inspector identified question; concerning the following areas:
(1) source te rm - the length of time used to calculate the term appears to be longer than the period of actual release which reduces the magnitude of the source term.
(2) effective stack height - the calculation disregarded the building height in determining the release point.
(3) building effects - the calculations disregarded the building wake effects although Section 7 of the license application includes a building wave correction factor.
(4) dispersion calculations - the calculations for the site boun-dary neglected ground ef fects on the plume at extended distances and the building effects.
(5) wind speed - the dispersion calculation used two different values for wind speed.
c.
The inspector discussed these points with the cognizant licensee representative. The licensee representative acknowledged the error in the wind speeds and the other comments and stated that the source term and dispersion calculations would be reevaluated. The inspector stated that the reevaluation would be reviewed during a subsequent inspection.