ML20237D180

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Responds to NRC 980716 RAI Re Licensee 980606 Submittal of Rev of Emergency Plan,Per 10CFR50.54(q)
ML20237D180
Person / Time
Site: MIT Nuclear Research Reactor
Issue date: 08/21/1998
From: Bernard J
MASSACHUSETTS INSTITUTE OF TECHNOLOGY, CAMBRIDGE
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TAC-M99060, NUDOCS 9808250118
Download: ML20237D180 (2)


Text

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, MASSACHUSETTS INSTITUTE OF TECHNOLOGY JOHN A. BERNARD 138 Albany Street, Cambndge, MA 021394296 Activation Analysis Director Telefax No. (617) 253-7300 Coolant Chemistry Director of Reactor Operations Tel. No. (02 J)3-42 20 Nirlear Mecheine Pnncipal Research Engineer Rextor Engineenng August 21,1998 Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555

Subject:

Massachusetts Institute of Technology Research Reactor, Emergency Plan, Docket No. 50-20, License No. R-37

Dear Sir or Madam:

On 6 June 1997, the Massachusetts Institute of Technology submitted a complete revision of its emergency plan to the U. S. Nuclear Regulatory Commission in accordance with 10 CFR 50.54 (q). On 16 July 1998, the NRC sent MIT a request for additional information. Enclosed is our response to that request.

Sincerely,

[ . L.w r ohn A. Bernard, Ph.D.

Director JAB /koe Enclosure cc: USNRC - Senior Project Manager, NRR/PDND; Mail Stop 0-Il-D-19 USNRC - Region I- Project Scientist

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PDR ADOCK 0500

.. Response to Request for AdditionalInformation Massachusetts Institute of Technology Emergency Plan Docket No. 50-20; License No. R-37 (TAC No, M99060)

Emergency Planning Zone (EPZ)

1. The EPZ for the original MITR emergency plan (version approved by USNRC on June 24, 1983 in letter from Cecil Thomas) was 100 meters. Please refer to definition 4.2.1 (i) and '

second paragraph of section 4.6.1 of the original plan (SR#-O-82-19 dated August 6, 1982). This 100 meter value was chosen based on NUREG-0849 (Appendix II). It is true that the original plan contained provisions for off-site protective actions out to a radius of

~ 0,5 miles. However, no analysis was performed for that distance and it was never considered to be the EPZ. The reason for its mention in the original plan (SR#-O-82-19 1 dated August 6,1982) was an historic artifact from the original MIT Research Reactor -l which was operated from 1958 to 1973. It is believed that the 0.5 mile figure was chosen I in 1958 in order to be ultra-conservative. Subsequent non-MIT analysis such as that which formed the basis of NUREG-0849 showed this to be unnecessary.

2. All areas shown in Fig. 4.2.1 are w ithin 100 meters of the MITR and hence within the i EPZ.

1 Classification

3. No conditions have changed since the last revision of the plan. The general emergency  ;

classification has never been credible for the MITR. It was included in the original MITR emergency plan (SR#-O-82-19 dated August 6,1982) because of the desire to be con' ;rvative. It has'since been realized that conservatism for conservatism's sake is not  !

appropriate. Rather, it is preferable for the plan to include only those situations that are realistic. Accordingly, the general emergency category is deleted in the current version.

Neither the current nor the arevious analysis (see text requested under item 4 below) supported its inclusion.~ Incic entally, a long standing NRC criticism of the original MITR i emergency plan was the inclusion of this emergency category, given the absence of a justification.

4. A copy of the full text and calculations of the abstract that was included with the submittal has been sent under separate cover to NRC (Non-Power Reactor and Decommissioning Project Directorate).

Emergency Action 12vels(EALs)

5. The term "whole body dose" was not replaced with the term " deep dose equivalent" because of an oversight. This change has now been made.
6. The intent of the plan is and always was that any single instrument reading that exceeded an

- EAL would activate the emergency plan. The language has now been clarified to make this clear, ' (Nng: One factor in the response to any radiological problem is to confirm an instrument signal based on other supporting information. Thus, should a single instrument somehow fail high in the complete absence of any supporting evidence of abnormal effluent radiation, there would not be an inappropriate over-reaction.)

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! 7. The signal from the particulate effluent monitor is displayed on a strip chart recorder. The l l slope of the trace allows determination of the rate of rise. We are considering other options

such as a rate of rise meter.

Emergency Response

8. The implementing procedures for the MITR emergency plan clearly specify that outside l- support agencies including the USNRC are to be notified within 15 minutes of the l, declaration of a NOUE. Please refer to page 5 of PM 4.4.4.15 which was provided to you previously. It clearly states that the on-duty supervisor is to notify all appropriate .

I government agencies including the USNRC. Please notify us if there is language m the plan which led you to conclude otherwise and we will modify that language.

9. The procedure to implement the original MITR emergency plan (SR#-O-82-19 dated August 6,1982) contained only one response to an airborne radiation release. The

'USNRC requested that separate procedures be developed for each emergency category.-

This was done but considerable duplication existed. We feel that the present plan is a marked impmvement in terms of human factors because the implementing procedures have ,

l been completely re-written to provide a smooth transition from one emergency category to )

l another and to eliminate duplication. This is what we meant by " graded response". j l In answer to the 'second'part of the question, the reason for performing the NOUE actions j l even if a more serious emergency exists is that the actions specified under the NOUE j

, procedure have to be performed in order to mitigate any emergency. This is part of our )

L graded approach whereby one response leads smoothly to another should the situation l deteriorate. (Note: Our original plan had been criticized by NRC because it Jacked this

!. feature.) Please refer to PM 4.4.4.15.

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