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Interpretation Response #06-0003 ([Thompson & Simmons, PLLC] [Mr. Charles T. Simmons])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Thompson & Simmons, PLLC

Individual Name: Mr. Charles T. Simmons

Location State: PA Country: US

View the Interpretation Document

Response text:

Jun 26, 2006

Mr. Charles T. Simmons                      Reference No. 06-0003
Thompson & Simmons, PLLC
1225 Nineteenth St., NW, Suite 300
Washington, DC 20036

Dear Mr. Simmons:

This is in response to your December 28, 2005 letter regarding the transportation of radionuclide-bearing drinking water treatment wastes under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically you ask: several questions related to the meaning of the phrase "natural materials" in § 173.40 1(b)(4). Your questions are paraphrased and answered as follows:

Q1. Does the exception for "natural materials" in § 173.40 1(b)(4) include naturally occurring zeolite water treatment medium that have absorbed naturally occurring radionuclides from public drinking water supplies and are intended to be managed as waste?

Al. The answer is no. The term “natural materials” in § 173.40l(b)(4) means materials and radionuclides existing in nature, not those produced by humans. Radionuclides addressed by § 173.401(b)(4) do not include those contained in filters used in removal of radionuclides from drinking water, produced in nuclear reactors, or by other technological means. In the scenario described in your letter, the naturally occurring radionuclides in public drinking water supplies are absorbed onto zeolite medium through a water treatment process. Therefore, these radionuclides, while naturally occurring in the pre-treatment drinking water, are not naturally occurring in the zeolite medium since they are transferred from another medium (i.e., the water). If the zeolite medium contains naturally occurring radionuclides prior to its use as a filtering medium, the exception in § 173.40 1(b)(4) is applicable. However, after the drinking water is processed through the zeolite medium and additional radionuclides are absorbed, § 173.40 1(b)(4) does not apply.

Q2. Do the radionuclide activity concentration values for exempt material in § 173.436 apply to parent nuclides when footnote b is referenced?

A2. The answer is yes. Daughter products listed in association with a specific: parent radionuclide in Footnote (b) in § 173.436 are accounted for when determining the exempt value for the parent in the Table in § 173.436.

Q3. Does the radium-228 activity concentration for exempt material account for progeny, including thorium-228 and its decay products?
A3. Thorium-228 is not included as a daughter product of radium-228. Based on Footnote (b) in § 173.436, only actinium-228 is accounted for in the activity concentration exemption value for radium-228.

Q4. May a person who offers for transportation a radium specific drinking water treatment media rely on the § 173.436 activity concentration value for radium-228 based on the parent nuclide only?

A4. The entry for radium-228 in Footnote (b) in § 173.436 specifies the presence of actinium-228 in secular equilibrium with radium-228. Other subsequent daughter products (e.g., thorium-228), if present in the material, must be accounted for separately when determining the effective activity concentration exemption value for the material utilizing the formula in § 173.433(d)(6).

I hope this information is helpful. If you have further questions, please do not hesitate to contact this office.



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards

173.401 (b) (4), 173.436

Regulation Sections

Section Subject
173.401 Scope
173.436 Exempt material activity concentrations and exempt consignment activity limits for radionuclides