ML20070L673

Environ Impact Appraisal for Continued Operation of Wa State Univ Modified Triga Reactor

ML20070L673
Person / Time
Site:	Washington State University
Issue date:	05/31/1979
From:	WASHINGTON STATE UNIV., PULLMAN, WA
To:
Shared Package
ML20070L663	List: ML20070L661 ML20070L673
References
NUDOCS 9103200152
Download: ML20070L673 (5)

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. ENVIRONMENTAL IMPACT APPRAISAL FOR THE CONTINUED OPERATION OF THE WASHINGTON STATE UNIVERSITY MODIFIED TRIGA REACTOR Submitted to:

U.S. Nuclear Regulatory Commission l

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WASHINGTON STATE UNIVERSITY NUCLEAR RADIATION CENTER l

Pullman, Washington 99164 I

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l May 1979 l

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6.0(e) Radiation Levels An extensive Environmental Radiation Monitoring Program was instituted at the WSU Nuclear Radiation Center in July of 1974. The program involves measuring the integrated radiation exposure for a period of three months at 40 points at the site and asso-clated environs, Commercially available thennoluminescent dosimeters (TLD's) of the CaSoeDy type provided and processed by the Radiation Detection Company, Sunnyvale, California, are utilized.

Table I lists the average exposure rate above ambient background per megawatt hour of reactor operation for a number oflocations at the site. The two highest exposure points are on the roof directly above the pool and at the freight door to the pool room. The maximum possible on-site exposure at a readily accessible location would be to an indivi-ual standing at the pool room freight door for the 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br /> per year that the reactor operates. The total maximum annual exposure at this on-site point would be 87 mrem / year.

The exposure rates at points from 50 meters to 24 kilometers from the Nuclear Radiation Center have also been monitored quarterly since 1974. The average exposure rate at the 24 locations involved is 188 30 R per day. No statistically significant vari-ations in the above background exposure rates at the sample locations have been observed or any exposure attributable to the operation of the WSU reactor. In addition, the average exposure rates at these locations which are 50 meters from the site are not statistically dif-ferent on a quarterly basis than the average of the background exposure rates at 17 locations in the State of Washington monitored by the State of Washington Department of Emer-gency Services. Thus, no significant effect on the radiation levels in the environment

surrounding the facility has been observed to date.

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TABLE 1 Median Exposure Rates per Megawatt Hour of Reactor Operation in Close Proximity to the Nuclear Radiation Center location (Adjacent to Room) Exposure (uR/MW-Hr)

Front Entrance 50V 32 Pool Room Freight Door 201 87 North Side of Building 201B 10 Roof above Control Room 2018 16 Roof above Pool 201 152 Roof above Laboratory Area 214- 0 West Side Door at Beam Room 2X 14 Storage Building 217A 21 Lower Loading Dock 123A 17

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, o (l') The irradiation meets all the specifications of Section 3.10 for an -

experiment.

(2) The expected radiation-field produced in air by the device or sample upon removal from the reactor pool is not more than 10 rem /hr beta and gamma equivalent at 1 ft; otherwise, it shall be classed as an experiment.

(3) The device or material is encapsulated in a' suitable container.

(4) The reactivity worth of the device or material is 0.25$ or less; otherwise, it shall be classed as an experiment.

(5) The device or material does not remain in the reactor for more than a 15-day period; otherwise, it-shall be classed as an experiment.

Basis: This specification is intended to provide assurance that the special class of experiments called irradiations avill be performed in a -manner that will not permit any safety limit to be exceeded.

3.12 As Low As Reasonably Achievable (ALARA) Radicactive Effluent Releases Apolicecility: This specification applies to the measures required to ensure that the radioactive effluents released from the facility are in accordance-with ALARA criteria.

Objective:

The objective is to limit the annual population radiation exposure owing to the operation of the WSU-TRIGA- reactor to a small percentage of the normal local background exposure.

Soecifications: 4 (1) In addition to-the radiation monitoring specified in Section 5,4, an environmental radiation monitoring program shall be conducted to measure the integrated radiation exposure-in and around'the. environs of the faci-lity on a quarterly basis.

(2) The annual-radiation exposure due to reactor operation, at the closest offsite point ~of extended occupancy shall not, on an-annual basis, exceed the average local offsite background radiation by more than'20%.

(3) Whenever practicable, the reactor shall be operated 4 in.-or more'from the thermal column in order to' minimize the production offargon-41.

(4)- The total annual discharge of argon-41 into the environment shall not; exceed 20 Ci per year.

(5) In the event of a significant fission product leak-from'a fuel rod-or a significant airborne radioactive release from a sample being: irradiated,-

as detected by the continuous air monitor, the reactor shall be shut-down until the source of the leak is located and eliminated. ' However,- the-reactor may be continued to be operated on a short-term basis as needed to assist in determining-the source of the leakage.

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• (6) Before discharge, the facility liquid effluents collected in the holdup tanks shall be analyzed for their beta gamma activity content. The total annual quantity of liquid effluents released (above background) shall not exceed 1 Ci per year.

Basis: The simplest and most reliable method of ensuring that ALARA release limits are accomplishing their objective of minimal facility-caused radiation exposure to the general public is to actually measure the integrated radiation exposure in the environment on and off the site.

3.13 Primary Coolant Conditions Applicability:

' This specification applies to the quality of the primary coolant in contact with the fuel cladding.

Objectives: The objectives are (1) to minimize the possibility for corrosion of the cladding on the fuel elements, and (2) to minimize neutron activation of dissolved materials.

Soecifications:

(1) Conductivity of the pool water shall be no higher than 5 x 10 6 mhos/cm.

(2) The pH of the pool water shall be between 5.0 and 7.5.

Bases: A small rate of corrosion continuously occurs in a water-metal system.

In order to limit this rate, and thereby extend the longevity and integrity of the fuel cladding, a water cleanup system is required. Experience with water quality control at many reactor facilities has shown that maintenance within the specified limits provides acceptable control.

By limiting the concentrations of dissolved materials in the water, the radio-activity of neutron activation products is limited. This is consistent with the ALTP.A principle, and tends to decrease the inventory of radionuclides in * ,'

tne entire coolant system, which will decrease personnel exposures during main-tenance and operations.

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