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Interpretation Response #07-0205 ([Tronox, LLC] [Mr. Mark Krippel])

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

Interpretation Response Details

Response Publish Date:

Company Name: Tronox, LLC

Individual Name: Mr. Mark Krippel

Location State: IL Country: US

View the Interpretation Document

Response text:

January 15, 2008

Mr. Mark Krippel

Tronox, LLC

800 Weyrauch Street

West Chicago, IL 60185

Ref. No. 07-0205

Dear Mr. Krippel:

This responds to your October 11, 2007 email requesting clarification of the applicability of hazardous substance requirements to the transportation of non-hazardous materials containing radionuclides under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether the HMR apply to the bulk transport of non-hazardous material containing naturally-occurring radionuclides that exceed the reportable quantity (RQ) threshold.

You indicate in your example that soil from a remediation site containing 10 pCi/g of thorium-232 is transported in a 103-ton capacity rail car and is subject to the HMR as a Class 9 hazardous substance because the total quantity in curies (Ci) in the rail car exceeds the RQ for thorium-232 (0.001 Ci).

Your understanding is correct. By definition, your example would qualify as a hazardous substance and be subject to the HMR. A hazardous substance (as defined in § 171.8) means a material, including its mixtures and solutions, that is listed in Appendix A to § 172.101 of the HMR; is in a quantity, in one package, that equals or exceeds the reportable quantity (RQ) listed in Appendix A to §172.101 of the HMR; and for radionuclides, when in a mixture or solution, conforms to paragraph 7 of Appendix A to §172.101.

The Superfund Amendments of 1986 require PHMSA to list and regulate as hazardous materials those hazardous substances listed or designated under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980. The intent of the requirement is to enable transporters of hazardous materials to identify CERCLA hazardous substances and to make the required notification if a release occurs. Additionally, based on guidance from the EPA Office of Solid Waste and Emergency Response, a release

of naturally-occurring radionuclides from the transportation of soil removed from a remediation site is subject to reporting under 40 CFR 302.6(c). Please consult 40 CFR 302.6(c) for categories of releases that are exempt from the EPA notification requirements.

I hope this information is helpful. Please contact us if you require additional assistance.


John A. Gale

Chief, Standards Development

Office of Hazardous Materials Standards

172.101, 171.8

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
172.101 Purpose and use of hazardous materials table