Letter Dated May 20, 1992, Regarding Alternative Method of Disposal for Contaminated Plastic Test Tubes
See the letter from R. E. Cunningham to K. B. Asarch (Diagnostic Products Corporation) dated June 26, 1992.
The letter responds to a request that the NRC provide a written position on: (1) the licensee's proposed method for decontamination and disposal of radioactively contaminated test tubes; and (2) whether there is a specific requirement for NRC licensees to obtain NRC approval of this disposal method pursuant to 10 CFR 20.302 [or, at present, 10 CFR 20.2003].
It is the NRC's position that each licensee must make an adequate survey of trash prior to disposal as required by 10 CFR 20.201 (b) [or, at present, 10 CFR 20.1501 (a) (2)]. If the trash is not known to contain radioactive material and its radiation exposure levels are not distinguishable from background, it may be disposed without regard to radioactive material disposal procedures (i.e., ordinary or non-radioactive trash). This would be the case with test tubes that are decontaminated (such as washed with bleach) and surveyed prior to disposal. This does not apply for decay-in-storage wastes as it is already known to contain radioactive material. Decay-in-storage waste must be held for the length of time specified in the license condition or in the regulations (generally 10 half-lives).
Licensees are required by 10 CFR 20.201 (b) [or 10 CFR 20.1501 (a) (2)] to make surveys that are "reasonable under the circumstances to evaluate the extent of radiation hazards that may be present." A licensee must be able to demonstrate to NRC inspectors that the method of survey used is capable of detecting the presence of radioactive material in the test tubes. If a licensee survey bulk groups of random samples of the test tubes rather than each single test tube, then the licensee must be able to demonstrate that their survey method is sufficient to detect all radioactive material prior to disposal. Preferably, licensees will document their tests to demonstrate survey adequacy.
Licensees are currently allowed to dispose of liquid effluents pursuant to 10 CFR 20.303 [or 10 CFR 20.2003], and if the test tubes are no longer contaminated, there are no controls on their disposal. Therefore, regarding the second request, it would not be necessary to obtain NRC approval for a practice specifically allowed by the regulations.
On January 1, 1994, the revised 10 CFR Part 20 becomes effective for all licensees. At that time, 10 CFR 20.2003 will limit disposal of licensed material into the sanitary sewer system. The limiting value for monthly average concentrations is 2 x 10-5 microcuries per milliliter for iodine-125, assuming that iodine-125 is the only radionuclide released into the sanitary sewers. The comparable limit is 4 x 10-5 microcuries per milliliter for release of soluble iodine-125 in the current Part 20. When a licensee implements the revised Part 20, the allowable release concentration drops by a factor of two. Regardless of how the test tubes are disposed, any releases of licensed material into the sanitary sewer system must meet the requirements of the current 10 CFR 20.303 or 10 CFR 20.2003 after implementation of the revised 10 CFR Part 20.
Regulatory references: 10 CFR 20.201, 10 CFR 20.303, 10 CFR 20.1501, 10 CFR 20.2003
Subject codes: 9.0, 9.2, 9.7
Applicability: Byproduct Material