ML19341C532
| ML19341C532 | |
| Person / Time | |
|---|---|
| Site: | 05000192 |
| Issue date: | 01/31/1981 |
| From: | TEXAS, UNIV. OF, AUSTIN, TX |
| To: | |
| References | |
| NUDOCS 8103030700 | |
| Download: ML19341C532 (3) | |
Text
7. RADIOACTIVE WASTES AND RADIATION ?ROTECTION
, 7.1 RADIOACTIVE WASTE 7.1.1 Design Basis. Radioactive vastes created by operation of the TRIGA reactor facility include fission products (high level waste) and activation p roduct s (low level waste). Since the reactor is to be operated without any failed fuel elements high level radioactive wastes are generated, con-tained, and removed as an integral part of the fuel element. Burnup charactersitics of the fuel elements indicate depletion of a fraction of the fuel material requiring reprocessing to recover the remaining fuel material. From the reactor operation history transportation of new and spent fuel elements is infrequent (less than one shipment every 5 years).
Shipments by an appropriate transport carrier are arranged as needed.
Low level radioactive wastes are categorized as gaseous, liquid and solid forms. The majority of the low level wastes generated by routine
. operation are activation products such as reactor components, experiment components, or irradiated sample materials. Provisions for disposal of los level solid wastes to an approved disposal site and liquid wastes to a sanitary sewer system are established through the University Gafety Office and state of Texas radioactive materials license.
Solid waste for disposal would consist of discarded equipment components, irradiated samples, and miscellaneous disposable contamination protection materials. Liquid waste such as samples or cleaning solutions would be solidifed or released as effluent as required. Gaseous waste coasists primarily of the activation product argon-41 and has been previously examined (Section 5.4).
1.1.2 Evaluation. Disposal of radioactive waste to an npproved fuel storage facility, waste disposal site, or as an effluent is monitored and 7-1
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controlled by the l'niversity Safety Office so that the correct requirements for t ransportation and disposal are in effect.
7.2. RADIATION PROTECTION 7.2.1 Shielding 7.2.1.1. Design Bases. The primary reactor shield is the pool water vertically and the massive concrete shield and the pool water radially.
The water depth (~20.5 f t) and the concrete thickness (~4.0 f t) has been designed to give more than adequate radiation protection to operating personnel with the reactor operating at 250 kW(t) under normal conditions.
7.2.1.2. Evaluation of the Shield. Complete gamma dose measurements have been taken around typical TRIGA reactors during 250 kW steady-state opera-tion.
These measurements give dose rates of 15 to 30 mr/hr at I ft above
- the surf ace of the water and 3 to 5 mr/hr at the handrail adjacent to the edge of the reactor tank with 16 f t of water over the core. Outside the concrete shield gamma dose rates, as measured, are 1 to 15 mr/hr.
No neutron leakage has been detected from operating TRIGA reactors except for a thermal neutron dose of about 0.03 mrem /hr (15 neutrons /cm -sec) l measured above the rotary specimen rack drive shaft tube during 100 kW operation.
1 7.2.2 Area Monitoring i
7.2.2.1. Design Bases.
Radiation detection devices are located at several laboratory locations to monitor radiation dose exposures.
GM tube detectors s with alarms and readouts at l the reactor console continuously monitor radia-(
tion levels in the vicinity of the console, heat j
system, exchanger, purification
. . and pnetenatic transfer system inlet / outlet.
operates near the A continuous air monitor laboratory entrance recording the activity levels of air t
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1 particulates in the room and providing audible and visual alarms of low and high level activities. Film badge monitors record the integrated doses at several locations in the vicinity of the reactor facility. From the reactor console the pool purification loop water activity and the room air ventilation exhaust are monitored by CM detectors or equivalent with high level alarms. A remote monitor of the exhaust stack and laboratory area is monitored near the laboratory entrance. Portable radiation monitoring equipment for a, S, y, and neutrons are available near the entrance to the laboratory. The portable equipment includes GM tubes, ionization chambers, l
scintillators, and proportional counters. A monitor for hands and feet is also available in the radiochemical area and near the laboratory entrance.
7.2.2.2. Evaluation of Area Monitoring. The combination cf radiation measurement instruments in operation and available should provide reliable indication of laboratory radiation conditions. Combined with routine calibrations and surveys the working conditions of the laboratory are main-
- , tained at na sate a condition as possible, t 7.2.3 Personnel Monitoring i .
i 7.2.3.1. Design Bases. Film badge measurements of laboratory personnel j exposures are made for 8, y, thermal and fast neutron radiations. Pocket dosimeters supplement film badge monitoring for gamma radiation or thermal neutrons in special situations of radiation exposure or for monitoring I occasional visitors in the laboratory.
- 7. 2. 3. 2. Evaluation of Personnel Monitoring. Records of radiation expo-sures to laboratory staff, students, and visitors allows monitoring both 1
personnel exposure and also laboratory access to visitors. Review of personnel exposure records aide the commitment to an "as low as reasonably achievable" radiation exposure program.
s 7-3 J