ML20070L661

Forwards Environ Impact Appraisal for Continued Operation of Wa State Univ Modified Triga Reactor,In Response to

ML20070L661
Person / Time
Site:	Washington State University
Issue date:	03/12/1991
From:	Wilson W WASHINGTON STATE UNIV., PULLMAN, WA
To:	Mendonca M Office of Nuclear Reactor Regulation
Shared Package
ML20070L663	List: ML20070L661 ML20070L673
References
NUDOCS 9103200146
Download: ML20070L661 (2)

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l Washington State University Nuclear Radiation Centor. Pullman, Washington 99164 1300 / 5o9-335-8641 '

Maren 12,1991 Marvin M. Mendonca Sr. Project Mgr., Non Power Keactors Office of Nuclear Regulatory Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Dear. Mr. Mendonca,

In response to your letter of February 14,1991, concerning the requested amendment tc, Section 3.12 of the WSU reactor facility Technical Specifications, the following informa-ion is provided:istorical Information Attached is a co py of Section 3.12 of the pro posed Technical Specifications for the WSU TRIGA reactor facility that was submitted wl1en the facility was relicensed in 1979. Also attached is a copy of the section of the Environmental Impact Appraisal conceming radia-tion levels that was also submitted during the relicensing process. At the time, there were no Federal requirements relating to ALARA criteria for non-?ower reactors and I do not believe any have been more recently established. Section 3. L2 of the pr,oposed and existing Facility Tectmical Specifications are really self-imposed limits and criteria to minimize the impact of the operanon of the facility on the radiation levels in the vacinity of the facility. The requirements of Section 3.12(2) were self imposed criteria that were arbitrarily selected to demonstrate that " fencepost dose" at the closest point of extended occupancy was not significantly increased by the operation of the facihty. The specified location was an old student housing complex that has since been torn down and thus the closest housing area is now further away from th< facility, Nonetheless, we have continued to monitor the old housing area and to check the exposure in this area with background as required by 3.12(2). General Resoonse The facility does not feel that it is appropriate to describe in detail all aspects of the self-imposed environmental monitoring program in writing to the Commission other than already described in the EIR. To do so would turn a voluntary system into a requirement that we could not alter in any way. Thus, we will only describe the system in very general terms and the old and newly proposed ALARA criteria in Section 3.12(2). Information on the calculation of the standard deviation of a set of data is contained in any good textbook on statistics, including " Applied General Statistics" by Croxton, Crowdin and Klein. J t-PDR l

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Marvin M. Mendonca March 12,1991 Page 2 Descriotica of Monitoring System The radiation levels at the facility, near the facility, on campus and in the Pullman area are monitored on a quarterly basis using commercial TLD-type dosimeters. The exposure measured by the TLD dosimeters at distances of from about 300 to 1200 meters from the facility are averaged to yield a background mdiation level in terms of pR/ day. A number of TLD dosimeters in the old student housing complex are averaged to detemline the exposure rate in pR/ day in this area. The exposure rate at the old housing complex has never exceeded the background exposure rate by more than 5% on a yearly basis over the past ten years. The present Section 3.12(2) limit is 20% increase. Statistical Analysis of Data A statistical analysis of six months of typical TLD data yielded a background exposure rate of 165 pR/ day. The measured standard deviation of this data set was 16 R/ day. The exposure rate at the old student housing complex for the same period of time was 160 pR/ day. Thus, the old 3.12(2) criteria of10% yields an allowable difference of 32 R/ day and a two sigma criteria also yields an allowable difference of 32 R/ day. The only differ-ence bet' ' n the two criteria is that the 20% is an arbitrary limit and the two-sigma limit has a ste .ical basis as outlined in the amendment request. Final Comments Since the old 3.12(2) criteria and the new proposed limit yield equivalent results, the faci-lity is, willing to retain the old criteria if the Commission would prefer to retain the existing critena. Sincerely, MEMk W.E. Wilson Associate Director Enclosure WEW:cre l}}