ML20126E176

Forwards Rev 5 to Emergency Plan for USGS Triga Reactor Facility. Review of Plan,Hazards Summary Analysis, NUREG-0849,Reg Guide 2.6 & Ans/Ansi Std 15.16 Prompted Rev

ML20126E176
Person / Time
Site:	U.S. Geological Survey
Issue date:	12/17/1992
From:	Hedge C INTERIOR, DEPT. OF, GEOLOGICAL SURVEY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20126E181	List: ML20126E176
References
RTR-NUREG-0849, RTR-NUREG-849, RTR-REGGD-02.006, RTR-REGGD-2.006 IEIN-92-079, IEIN-92-79, NUDOCS 9212290041
Download: ML20126E176 (3)

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GI 01 DGICAl. %I'g Y liO N 2*,016 MX ALi- 1)! NV111 I I I)I R AI. Ll N I I R 1)! NY) 10 ( OI .OR Al)O A0225 nioni ni,ain December 17, 1992 Ref: Docket 50-274 Document Control Desk U.S. Nuclear Regulatory Commission Wmshington, D.C. 20555 Sirst Enclosed are three copies of Revision 5 of the Emergency Plan for the U.S. Geological Survey TRIGA Reactor (GSTR) Facility. The plan was revised as permitted by 10 CFR 50.54(q) and this report is submitted accordingly. The recently issued NRC Information Notice 92-79 states that emergency action levels and notification criteria have been found to vary greatly among licensees. A review of our Emergency Plan, our Hazards Summary Analysis,

• NUREG-0849, Regulatory Guide 2.6 and ANS/ ANSI Standard 15.16 has prompted the attached revision. The reactor staff has reviewed the proposed changes to the Emergency Plan and feel that they do not decrease the effectiveness of the plan.

The changed _ text areas of the plan are marked with a vertical line in the left margins on the respective pages. Explanations of the changes are as follows, with page numbers referring to the previously approved Revision 4.

1. p.9, Section 4.1 - Classifications of Emergencies 4.1.3 Site Area Emergency was removed since this is not considered to be a credible emergency class for the GSTR.

2. p.9, Section 4.2.1.1 - Changed " Sustained Fire Onsite" to be

" Sustained fire at the facility that does not involve reactor controls or radioactive materials." This change was made to prevent the need to declare a reactor emergency when a remote site fire existed, external to the reactor facility.

3. p.9, Section 4.2.1.2 (2) - Changed " flooding" to be

" flooding of the reactor vital area". This change was made to prevent the need to declare a reactor emergency when flooding occured in other site areas.

4. p.9, Sections 4.2.1.3 and 4.2.1.4 were combined to make the new Section 4.2.1.3. This change is tc make the Plan consistent with the NRC and ANSI guidance.

5. p.9, Section 4.2.1.5 - Renumbered to be Section 4.2.1.4.

6., p.9, Section 4.2.1.6 - Renumbered to be Section 4.2.1.5.

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7. p.9, Second Section 4.2.1.6 - This item was deleted. This was done because fuel damage is determined by the release of radionuclides. This release will be detected by the continuous-air monitor and this event is addressed by Section 4.2.1.5.

8. p.9, Section 4.2.1.7 - This item was delected. The TRIGA Mk i I design has the reactor tank and core below grade, I surrounded by at least 3 feet of reinforced concreto. All pumps, piping, and valves are located above the core. All '

piping enters the tank from the top. The auction pipe for the primary pump extends only a few feet into the reactor. i tank. Therefore it is not credible to have a loss of ,

coolant accident that could threaten to uncover the core.  ;

In addition, no core damage would occur even if all water i was removed from the core region.

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9. p.9, Sections 4.2.2.1 and 4.2.2.4 - These items were combined and revised as the new Section 4.2.2.1. The '

ambiguous statements of "might affect" and " imminent" made the original action levels virtually impossible to assess.  !

It is more realistic to consolidate the hazards in this section as being from fire or explosions. A new Section 4.2.2.4 was added to cover fission product releases that could meet the criteria of 4.2.2.2 or 4.2.2.3.

10. p.10, Section 4.2.2.5 - This item was deleted. Section 4.2.2.3 is a more limiting action level since a dose rate of 20 mrom/hr at the site boundary would be reached before 100-mrem /hr could be achieved throughout the reactor building.

This occurs because the site boundary is approximately 50 feet from the_ reactor room while portions of the building -

are more than 150 feet from the reactor room.

11. p.10, Section 4.2.2.6 - This item was deleted. As_noted in F item 8, it is not credible to have a loss of coolant accident that could threaten to uncover the core. In.

addition, no core damage would occur even if all water was removed from the core region.

12. p.10, Section 4.2.3 and all subsections (4.2.3.1 through l_ 4.2.3.5) - These items are deleted because no credible accidents at the GSTR would meet the criteria-for a site area emergency. The worst case fuel element rupture would be after a long, high power operation and with_the1 element removed-from the reactor-tank. Such a fuel element rupture i in air would give a maximum effluent-level of about 100 MPC avalaged over 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and a maximum thyroid dosefof:about 330 mrom at_the site boundary. Experiment restrictions _ .

limit the potential for experiment failures to approximately l 50 mrem /hr short term dose at the site boundary. . These levels are below the criteria for a site area emergency.

Subsections 4.2.3.3 through_4.2.3.5 do not meet the guidance

• criteria for a site area emergency. In addition,1they have little credibility _and are not objective criteria.

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13. p.10,-Section 4.4.2, last paragraph - A sentence was'added to require NRC notification of alert conditions at the facility.

Please contact Tim DeBay at'(303) 236-4726 if you have questions regarding this emergency plan revision or need further details.

Sincerely, O~f/bA Dr. Carl liedge y

Reactor Administrator r

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Copy to:

U.S. Nuclear Regulatory Commission ATTN Mr. L.J. Callan 611 Ryan_ Plaza Drive, Suite 400 Arlington, TX 76011 -

Tim DeBoy, USGS, MS 974 I

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