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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #09-0013 ([Clean Harbors Environmental Services, Inc.] [Mr. Anthony P. Cellucci])

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

Interpretation Response Details

Response Publish Date:

Company Name: Clean Harbors Environmental Services, Inc.

Individual Name: Mr. Anthony P. Cellucci

Location State: MA Country: US

View the Interpretation Document

Response text:

April 8, 2009





Mr. Anthony P. Cellucci

Director, Transportation Compliance

Clean Harbors Environmental Services, Inc.

42 Longwater Drive

Norwell, MA 02061-9149

Ref. No.: 09-0013

Dear Mr. Cellucci:

This responds to your electronic mail requesting clarification of the Hazardous Material Regulations (HMR; 49 CFR Parts 171-180) pertaining to the classification of explosives. Specifically, you request clarification on when an approval is needed for a waste stream containing a small amount of a Class 1 (explosive) material. You also ask if there is a threshold upon which an assumption may be made by the shipper that the material meets the definition of another hazard class or does not meet the definition of a hazardous material.

Your email provides two scenarios. In the first, a customer manufactures Trinitrotrimethylenetriamine (RDX) by incorporating the material into a solution of isopropanol and water in order to regulate the particle size. The explosive material is then removed from the isopropanol/water/RDX solution in a rotary evaporation procedure. The resultant waste material consists of a solution that contains 4.5% water, 93.7% isopropanol, 1.73% bis(2ethylhexyl) adipate (a non- DOT regulated plasticizer), .07% RDX and a non-detectable amount of cyclotetramethylenetetramine (HMX). In the second, a remediation project is conducted in which contaminated soils that contain trace amounts of RDX and/or HMX are excavated for disposal at a licensed waste management facility.

A new explosive is an explosive produced by a person who has not previously produced that explosive, or has previously produced that explosive but has made a change in the formulation, design, or process so as to alter any of the properties of the explosive. The term "formulation" as used in the definition of a new explosive applies to the entire mixture and not just the explosive components. An explosive is not considered a "new explosive" if an agency listed in paragraph (b) of §173.56 has determined and confirmed in writing to the Associate Administrator that there are no significant differences in hazard characteristics from the explosive previously approved (see 173.56(a)).

All new compositions containing any amount of explosive material must be classed and approved by DOT, including compositions of diluted (desensitized) explosives or explosives combined or contaminated with other materials. An approved explosive that has been mixed with non-explosive or non-hazardous materials may be considered a new explosive if the change in formulation increases its sensitivity toward initiation or energetic content. An approved explosive that is to be discarded as a waste because it is off-spec would be a new explosive if the change in formulation that causes the material to be off-spec would increase the sensitivity toward initiation or energetic content of the explosive. Therefore, if the explosive properties of an approved explosive are increased after being mixed with filters, rags, dirt, or other material, then the explosive produced is a new explosive and must be approved in accordance with §173.56(b).

In accordance with §173.56(i), if experience or other data indicate that the hazard of a material or a device containing an explosive composition is greater or less than indicated according to the definition and criteria specified in §§173.50, 173.56 and 173.58, the Associate Administrator may specify a classification or except the material or device from the requirements of the HMR.

I hope this information is helpful. If we can be of further assistance, please contact us.


Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards














April 8, 2009


April 8, 2009

Regulation Sections

Section Subject
173.56 New explosives-definition and procedures for classification and approval