49 CFR Part 173, Subpart D - Definitions Classification, Packing Group Assignments and Exceptions for Hazardous Materials Other Than Class 1 and Class 7

The Pipeline and Hazardous Materials Safety Administration (PHMSA) requests information on matters related to the development and potential use of automated technologies for surface modes ( i.e., highway and rail) in hazardous materials transportation. In anticipation of the development, testing, and integration of Automated Driving Systems in surface transportation, PHMSA is issuing this request for information on the factors the Agency should consider to ensure continued safe transportation of hazardous materials without impeding emerging surface transportation technologies.

PHMSA is issuing a final rule to amend the Hazardous Materials Regulations (HMR) to maintain consistency with international regulations and standards by incorporating various amendments, including changes to proper shipping names, hazard classes, packing groups, special provisions, packaging authorizations, air transport quantity limitations, and vessel stowage requirements. These revisions are necessary to harmonize the HMR with recent changes made to the International Maritime Dangerous Goods Code, the International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air, and the United Nations Recommendations on the Transport of Dangerous Goods—Model Regulations. Additionally, PHMSA is adopting several amendments to the HMR that result from coordination with Canada under the U.S.-Canada Regulatory Cooperation Council.

PHMSA is extending the comment period for an advance notice of proposed rulemaking that was published in the Federal Register on January 18, 2017. In response to stakeholder requests, the comment period will be extended for an additional 60 days, from March 20, 2017 to May 19, 2017.

PHMSA is considering revising the Hazardous Materials Regulations (HMR) to establish vapor pressure limits for unrefined petroleum-based products and potentially all Class 3 flammable liquid hazardous materials that would apply during the transportation of the products or materials by any mode. PHMSA is currently assessing the merits of a petition for rulemaking submitted by the Attorney General of the State of New York regarding vapor pressure standards for the transportation of crude oil. The petition requests that PHMSA implement a Reid Vapor Pressure (RVP) limit less than 9.0 pounds per square inch (psi) for crude oil transported by rail. PHMSA will use the comments in response to this ANPRM to help assess and respond to the petition and to evaluate any other potential regulatory actions related to sampling and testing of crude oil and other Class 3 hazardous materials. PHMSA will also evaluate the potential safety benefits and costs of utilizing vapor pressure thresholds within the hazardous materials classification process for unrefined petroleum-based products and Class 3 hazardous materials.

The Pipeline and Hazardous Materials Safety Administration (PHMSA) proposes to amend the Hazardous Materials Regulations (HMR) to maintain consistency with international regulations and standards by incorporating various amendments, including changes to proper shipping names, hazard classes, packing groups, special provisions, packaging authorizations, air transport quantity limitations, and vessel stowage requirements. These revisions are necessary to harmonize the HMR with recent changes made to the International Maritime Dangerous Goods Code, the International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air, and the United Nations Recommendations on the Transport of Dangerous Goods—Model Regulations. Additionally, PHMSA proposes several amendments to the HMR that result from coordination with Canada under the U.S.-Canada Regulatory Cooperation Council.

The Pipeline and Hazardous Materials Safety Administration is issuing this final rule to codify in the Hazardous Materials Regulations certain mandates and minimum requirements of the FAST Act. Specifically, the FAST Act mandates a revised phase-out schedule for all DOT Specification 111 tank cars used to transport unrefined petroleum products ( e.g., petroleum crude oil), ethanol, and other Class 3 flammable liquids. The FAST Act also requires that each tank car built to meet the DOT Specification 117 and each non-jacketed tank car retrofitted to meet the DOT Specification 117R be equipped with a thermal protection blanket that is at least 1/2 -inch thick and meets existing thermal protection standards. Further, the FAST Act mandates minimum top fittings protection requirements for tank cars retrofitted to meet the DOT Specification 117R.

PHMSA, in consultation with the Federal Railroad Administration, is issuing this NPRM to propose revisions to regulations that would expand the applicability of comprehensive oil spill response plans (OSRPs) based on thresholds of liquid petroleum oil that apply to an entire train consist. Specifically, we are proposing to expand the applicability for comprehensive OSRPs so that any railroad that transports a single train carrying 20 or more loaded tank cars of liquid petroleum oil in a continuous block or a single train carrying 35 or more loaded tank cars of liquid petroleum oil throughout the train consist must also have a current comprehensive written OSRP. We are further proposing to revise the format and clarify the requirements of a comprehensive OSRP ( e.g., requiring that covered railroads develop response zones describing resources available to arrive onsite to a worst-case discharge, or the substantial threat of one, which are located within 12 hours of each point along the route used by trains subject to the comprehensive OSRP). We also solicit comment on defining high volume areas and staging resources using alternative response times, including shorter response times for spills that could affect such high volume areas. Further, in accordance with the Fixing America's Surface Transportation Act of 2015, this action proposes to require railroads to share information about high-hazard flammable train operations with state and tribal emergency response commissions to improve community preparedness and seeks comments on these proposals. Lastly, PHMSA is proposing to incorporate by reference an initial boiling point test for flammable liquids from the ASTM D7900 method referenced in the American National Standards Institute/American Petroleum Institute Recommend Practices 3000, “Classifying and Loading of Crude Oil into Rail Tank Cars,” First Edition, September 2014 as an acceptable testing alternative to the boiling point tests currently specified in the HMR. PHMSA believes providing this additional boiling test option provides regulatory flexibility and promotes enhanced safety in transport through accurate packing group assignment.

The Pipeline and Hazardous Materials Safety Administration (PHMSA) is proposing to amend the Hazardous Materials Regulations to revise certain requirements applicable to the manufacture, use, and requalification of DOT-specification cylinders. PHMSA is taking this action in response to petitions for rulemaking submitted by stakeholders and to agency review of the compressed gas cylinders regulations. Specifically, PHMSA is proposing to incorporate by reference or update the references to several Compressed Gas Association publications, amend the filling requirements for compressed and liquefied gases, expand the use of salvage cylinders, and revise and clarify the manufacture and requalification requirements for cylinders.

In response to petitions for rulemaking submitted by the regulated community, PHMSA proposes to amend the Hazardous Materials Regulations (HMR; 49 CFR parts 171 through 180) to update, clarify, or provide relief from miscellaneous regulatory requirements. Specifically, PHMSA is proposing amendments that include, but are not limited to, the following: Incorporating by Reference (IBR) multiple publications from both the Compressed Gas Association (CGA) and the Chlorine Institute; addressing inconsistencies with domestic and international labels and placards; permitting alternative testing for aerosols; no longer mandating that excepted quantities comply with the emergency response telephone requirement; allowing electronic signatures for Environmental Protection Agency (EPA) manifest forms; and no longer requiring the service pressure to be marked on Department of Transportation (DOT) 8 and 8L cylinders.

In this final rule, the Pipeline and Hazardous Materials Safety Administration (PHMSA) is amending the Hazardous Materials Regulations (HMR) to make miscellaneous amendments in order to update and clarify certain regulatory requirements. These amendments are designed to promote safer transportation practices, address petitions for rulemaking, respond to National Transportation Safety Board (NTSB) Safety Recommendations, facilitate international commerce, make editorial corrections, and simplify the regulations. The amendments in this rulemaking include, but are not limited to, removing the packing group (PG) II designation for certain organic peroxides, self-reactive substances, and explosives; incorporating requirements for trailers of manifolded acetylene cylinders; providing requirements to allow for shipments of damaged wet electric batteries; and revising the requirements for the packaging of nitric acid, testing of pressure relief devices on cargo tanks, and shipments of black or smokeless powder for small arms.

In this final rule, the Pipeline and Hazardous Materials Safety Administration (PHMSA) is adopting regulatory amendments applicable to the reverse logistics shipments of certain hazardous materials by highway transportation. This final rule revises the Hazardous Materials Regulations (HMR) to include a definition of “reverse logistics” and provides appropriate provisions for hazardous materials within the scope of this definition. This final rule also expands a previously existing exception for return shipments of used automobile batteries transported between a retail facility and a recycling center. The PHMSA incorporated recommendations from petitions for rulemaking and public comment into this rulemaking.

As required by the Moving Ahead for Progress in the 21st Century Act (MAP-21), the Pipeline and Hazardous Materials Safety Administration is amending the Hazardous Materials Regulations to adopt provisions contained in certain widely-used or long-standing special permits that have an established safety record. The adopted amendments are intended to provide wider access to the regulatory flexibility offered in special permits and eliminate the need for numerous renewal requests. The adopted amendments will also reduce paperwork burdens and facilitate commerce while maintaining an appropriate level of safety. PHMSA conducted an extensive analysis of all active special permits and codified, as appropriate, those special permits deemed suitable in this rulemaking.

PHMSA is withdrawing the notice proposing to stop the transportation of flammable liquid material in unprotected external product piping on DOT specification cargo tank motor vehicles as mandated by the “Fixing America's Surface Transportation Act” or the “FAST Act”. Although PHMSA is withdrawing its rulemaking proposal, the agency will continue to consider methods to improve the safety of transporting flammable liquid by cargo tank motor vehicle. PHMSA will also continue to analyze current incident data and improve the collection of future incident data to assist in making an informed decision on methods to address this issue further, if warranted.

The Pipeline and Hazardous Materials Safety Administration (PHMSA) is amending the Hazardous Materials Regulations by establishing standards for the safe transportation of explosives on cargo tank motor vehicles and multipurpose bulk trucks transporting materials for blasting operations. This rulemaking is responsive to two petitions for rulemaking submitted by industry representatives: P-1557, concerning the continued use of renewal applications, and P-1583, concerning the incorporation of an industry standard publication. Further, developing these requirements provides wider access to the regulatory flexibility currently only offered by special permits and competent authorities. The requirements of this final rule mirror the majority of provisions contained in nine widely-used longstanding special permits that have established safety records. These requirements eliminate the need for future renewal requests, thus reducing paperwork burdens and facilitating commerce while maintaining a commensurate level of safety. This final rule authorizes the transportation of certain explosives, ammonium nitrates, ammonium nitrate emulsions, and other specific hazardous materials in both non-bulk and bulk packagings, which are not otherwise authorized under current regulations. These hazardous materials are used in blasting operations on cargo tank motor vehicles and specialized vehicles, known as multipurpose bulk trucks, which are used as mobile work platforms to create blends of explosives that are unique to each blast site. Finally, this rulemaking addresses the construction of new multipurpose bulk trucks.

This final rule corrects editorial errors, makes minor regulatory changes and, in response to requests for clarification, improves the clarity of certain provisions in the Hazardous Materials Regulations. The intended effect of this rule is to enhance the accuracy and reduce misunderstandings of the regulations. The amendments contained in this rule are non-substantive changes and do not impose new requirements.

On May 8, 2015, the Pipeline and Hazardous Materials Safety Administration, in coordination with the Federal Railroad Administration (FRA), published a final rule entitled “Hazardous Materials: Enhanced Tank Car Standards and Operational Controls for High-Hazard Flammable Trains,” which adopted requirements designed to reduce the consequences and, in some instances, reduce the probability of accidents involving trains transporting large quantities of Class 3 flammable liquids. The Hazardous Materials Regulations provide a person the opportunity to appeal a PHMSA action, including a final rule. PHMSA received six appeals regarding the final rule, one of which was withdrawn. This document responds to the five remaining appeals submitted by the Dangerous Goods Advisory Council (DGAC), American Chemistry Council (ACC), Association of American Railroads (AAR), American Fuel & Petrochemical Manufacturers (AFPM), and jointly the Umatilla, Yakama, Warm Springs, and Nez Perce tribes (Columbia River Treaty Tribes) and the Quinault Indian Nation (Northwest Treaty Tribes).

In this final rule, the Pipeline and Hazardous Materials Safety Administration (PHMSA), in coordination with the Federal Railroad Administration (FRA), is adopting requirements designed to reduce the consequences and, in some instances, reduce the probability of accidents involving trains transporting large quantities of flammable liquids. The final rule defines certain trains transporting large volumes of flammable liquids as “high-hazard flammable trains” (HHFT) and regulates their operation in terms of speed restrictions, braking systems, and routing. The final rule also adopts safety improvements in tank car design standards, a sampling and classification program for unrefined petroleum-based products, and notification requirements. These operational and safety improvements are necessary to address the unique risks associated with the growing reliance on trains to transport large quantities of flammable liquids. They incorporate recommendations from the National Transportation Safety Board (NTSB) and from the public comments, and are supported by a robust economic impact analysis.

The Pipeline and Hazardous Materials Safety Administration's (PHMSA), Office of Hazardous Materials Safety (OHMS), is revising its application-approval procedures for previously approved firework designs and clarifying requirements for assigning Explosives (EX) Approval or Fireworks Certification (FC) numbers. It is not required or necessary for a firework manufacturer, or designated agent, to submit a new EX Approval application each time an additional item name is associated with a firework design type (described under UN0336, UN0335, and UN0431). PHMSA will no longer process additional item name EX Approval applications, effective immediately.

PHMSA is extending for modes of transportation other than air the mandatory compliance date of a final rule published on August 6, 2014, under Docket No. HM-224F from February 6, 2015, until August 7, 2015. This extension is made in response to formal comments received from multiple stakeholders outlining challenges faced by the regulated community in fully implementing the provisions of the final rule by the February 6, 2015 mandatory compliance date.

As required by the Moving Ahead for Progress in the 21st Century Act (MAP-21), the Pipeline and Hazardous Materials Safety Administration is proposing to amend the Hazardous Materials Regulations to adopt provisions contained in certain widely-used or long-standing special permits that have an established safety record. The proposed revisions are intended to provide wider access to the regulatory flexibility offered in special permits and eliminate the need for numerous renewal requests, thus reducing paperwork burdens and facilitating commerce while maintaining an appropriate level of safety. PHMSA conducted an extensive analysis of all active special permits and, in this rulemaking, those special permits deemed suitable are being proposed for adoption. PHMSA is inviting all interested persons to provide comments on both those special permits deemed suitable and proposed to be adopted into the HMR and those that are deemed not suitable for adoption. In addition, PHMSA is also requesting comments on a proposed requirement for special permit applicants to include regulatory text in their applications, when appropriate.

PHMSA proposes to make miscellaneous amendments to the Hazardous Materials Regulations to update and clarify certain regulatory requirements. These proposed amendments are designed to promote safer transportation practices, address petitions for rulemaking, respond to National Transportation Safety Board (NTSB) Safety Recommendations, facilitate international commerce, make editorial corrections, and simplify the regulations. The proposed provisions in this rulemaking include, but are not limited to, removing the packing group (PG) II designation for certain organic peroxides, self-reactive substances and explosives, incorporating requirements for trailers of manifolded acetylene cylinders, and providing requirements to allow for shipments of damaged wet electric batteries. In addition, this rulemaking proposes to revise the requirements for the packaging of nitric acid, testing of pressure relief devices on cargo tanks, and shipments of black or smokeless powder for small arms.

PHMSA is amending the Hazardous Materials Regulations to maintain alignment with international standards by incorporating various amendments, including changes to proper shipping names, hazard classes, packing groups, special provisions, packaging authorizations, air transport quantity limitations, and vessel stowage requirements. These revisions are necessary to harmonize the Hazardous Materials Regulations with recent changes made to the International Maritime Dangerous Goods (IMDG) Code, the International Civil Aviation Organization's Technical Instructions (ICAO TI) for the Safe Transport of Dangerous Goods by Air, the United Nations Recommendations on the Transport of Dangerous Goods (UN Model Regulations) and subsequently address three petitions for rulemaking.

PHMSA is notifying the public of its intent to extend the comment period by thirty days for a notice of proposed rulemaking entitled “Hazardous Materials: Reverse Logistics” under Docket Number PHMSA-2011-0143 (HM-253) published in the Federal Register on August 11, 2014.

PHMSA proposes to amend the Hazardous Materials Regulations to maintain alignment with international standards by incorporating various amendments, including changes to proper shipping names, hazard classes, packing groups, special provisions, packaging authorizations, air transport quantity limitations, and vessel stowage requirements. These revisions are necessary to harmonize the Hazardous Materials Regulations with recent changes made to the International Maritime Dangerous Goods Code, the International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air, the United Nations Recommendations on the Transport of Dangerous Goods—Model Regulations and subsequently address three petitions for rulemaking.

PHMSA is proposing to revise the Hazardous Materials Regulations applicable to return shipments of certain hazardous materials by motor vehicle. PHMSA proposes a definition for “reverse logistics” for hazardous materials that are intended to be returned to or between a vendor, distributor, manufacturer, or other person for the purpose of returning for credit, recalling product, replacement, or similar reason (for instance, from a retail or wholesale outlet). PHSMA proposes to establish a new section in the regulations to provide an exception for materials that are transported in a manner that meets the definition of “reverse logistics.” In this exception, PHMSA proposes to clearly identify the hazardous materials authorized, packaging, hazard communication, and training requirements applicable to reverse logistics shipments. In addition to providing a new reverse logistics exception, this rulemaking also proposes to expand an existing exception for reverse logistics shipments of used automobile batteries that are being shipped from a retail facility to a recycling center.

PHMSA, in consultation with the Federal Aviation Administration (FAA), is modifying the requirements governing the transportation of lithium cells and batteries. This final rule revises hazard communication and packaging provisions for lithium batteries and harmonizes the Hazardous Materials Regulations (HMR) with applicable provisions of the United Nations (UN) Model Regulations, the International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICAO Technical Instructions) and the International Maritime Dangerous Goods (IMDG) Code.

The Pipeline and Hazardous Materials Safety Administration (PHMSA or we), in coordination with the Federal Railroad Administration (FRA), is proposing: new operational requirements for certain trains transporting a large volume of Class 3 flammable liquids; improvements in tank car standards; and revision of the general requirements for offerors to ensure proper classification and characterization of mined gases and liquids. These proposed requirements are designed to lessen the frequency and consequences of train accidents/incidents (train accidents) involving certain trains transporting a large volume of flammable liquids. The growing reliance on trains to transport large volumes of flammable liquids poses a significant risk to life, property, and the environment. These significant risks have been highlighted by the recent instances of trains carrying crude oil that derailed in Casselton, North Dakota; Aliceville, Alabama; and Lac-Mégantic, Quebec, Canada. The proposed changes also address National Transportation Safety Board (NTSB) safety recommendations on the accurate classification and characterization of such commodities, enhanced tank car construction, and rail routing.

The Pipeline and Hazardous Materials Safety Administration is proposing to amend the Hazardous Materials Regulations by establishing standards for the safe transportation of bulk explosives. This rulemaking would be responsive to two petitions for rulemaking submitted by industry representatives: P-1557 concerning the continued use of renewal applications, and P-1583 concerning the incorporation of an industry standard publication. Further, developing these requirements would provide wider access to the regulatory flexibility currently only offered by special permit and competent authorities. The requirements of this proposed rule would mirror the majority of provisions contained in nine widely used or longstanding special permits that have established safety records. These proposed revisions are intended to eliminate the need for future renewal requests, thus reducing paperwork burdens and facilitating commerce while maintaining an appropriate level of safety. As proposed, the requirements would authorize the transportation of certain explosives, ammonium nitrates, ammonium nitrate emulsions, and other specific hazardous materials in bulk packagings, which are not otherwise authorized under the regulations. These hazardous materials are used in blasting operations on specialized vehicles, known as multipurpose bulk trucks, which are used as mobile work platforms to create blends of explosives that are unique for each blast site. Finally, this rulemaking addresses the construction of new multipurpose bulk trucks.

PHMSA, in coordination with the Nuclear Regulatory Commission (NRC), is amending requirements in the Hazardous Materials Regulations (HMR) governing the transportation of Class 7 (radioactive) materials based on recent changes contained in the International Atomic Energy Agency (IAEA) publication “Regulations for the Safe Transport of Radioactive Material, 2009 Edition, IAEA Safety Standards Series No. TS-R-1.” The purposes of this rulemaking are to harmonize requirements of the HMR with international standards for the transportation of Class 7 (radioactive) materials and update, clarify, correct, or provide relief from certain regulatory requirements applicable to the transportation of Class 7 (radioactive) materials.

The Pipeline and Hazardous Materials Safety Administration is amending the Hazardous Materials Regulations (HMR) to adopt provisions contained in certain widely used or longstanding special permits and certain competent authority approvals (“approvals”) that have established safety records. Special permits allow a company or individual to package or ship a hazardous material in a manner that varies from the regulations provided an equivalent level of safety is maintained. An approval is a written consent (document) required under an international standard (i.e., International Maritime Dangerous Goods (IMDG) Code, International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICAO TI)), or is specifically provided for in the HMR, and is issued by the Associate Administrator for Hazardous Materials Safety. These revisions are intended to provide wider access to the regulatory flexibility offered in special permits and approvals and eliminate the need for numerous renewal requests, reducing paperwork burdens and facilitating commerce while maintaining an appropriate level of safety.

PHMSA is notifying the public of our intent to extend the comment period by thirty days for a notice of proposed rulemaking published on December 30, 2013.

PHMSA is proposing to amend the Hazardous Materials Regulations applicable to the design, construction, certification, recertification and maintenance of cargo tank motor vehicles, cryogenic portable tanks and multi-unit tank car tanks (ton tanks) in response to petitions for rulemaking from the American Society of Mechanical Engineers (ASME), the National Board of Boiler and Pressure Vessel Inspectors (National Board), and the Pressure Vessel Manufacturers Association (PVMA). Specifically, this NPRM proposes to allow the use of the 2013 edition of the ASME's Boiler and Pressure Vessel Code, Section XII (Section XII) for the design, construction, and certification of cargo tank motor vehicles, cryogenic portable tanks and ton tanks. PHMSA also proposes to authorize the use of the 2013 edition of the National Board of Boiler and Pressure Vessel Inspectors' National Board Inspection Code (NBIC), as it applies to the continuing qualification and maintenance of ASME constructed cargo tank motor vehicles, cryogenic portable tanks, and ton tanks constructed to standards in ASME's Section XII, and existing cargo tank motor vehicles and portable tanks constructed to Section VIII, Division 1. If adopted, these amendments will allow for regulatory flexibility, without compromising safety.

PHMSA is notifying the public of our intent to extend the comment period by 30 days for a notice of proposed rulemaking published on September 6, 2013.

This final rule corrects editorial errors and amends certain requirements in response to administrative appeals submitted by persons affected by certain final rules published in the Federal Register .

PHMSA is considering revisions to the Hazardous Materials Regulations (HMR) to improve the regulations applicable to the transportation of hazardous materials by rail. The revisions are based on eight petitions received from the regulated community and four National Transportation Safety Board (NTSB) Recommendations which are referenced by a petition. In this ANPRM, we outline the petitions and NTSB recommendations, identify a preliminary estimate of costs and benefits from the petitions, pose several questions, and solicit comments and data from the public. Under Executive Order 13563, Federal agencies were asked to periodically review existing regulations. The questions posed in this ANPRM and responses by commenters will be used in conjunction with a retrospective review of existing requirements aimed to modify, streamline, expand, or repeal existing rules that are outmoded, ineffective, insufficient, or excessively burdensome.

The Pipeline and Hazardous Materials Safety Administration is amending the Hazardous Materials Regulations applicable to air bag inflators, air bag modules, and seat-belt pretensioners. The revisions incorporate the provisions of two special permits into the regulations. In addition, PHMSA is amending the current approval and documentation requirements for a material classified as a UN3268 air bag inflator, air bag module, or seat-belt pretensioner. These revisions are intended to reduce the regulatory burden on the automotive industry and facilitate commerce, while continuing to maintain an equivalent level of safety.

PHMSA is revising the Hazardous Materials Regulations applicable to the approval of Division 1.4G consumer fireworks (UN0336 Fireworks) and establishing DOT-approved fireworks certification agencies that provide an alternative to the approval process for Division 1.4G consumer fireworks. PHMSA is also reformatting the procedural regulations pertaining to certification agencies. These actions clarify regulations with respect to PHMSA's fireworks approval process and provide regulatory flexibility in seeking authorization for the transportation of Division 1.4G consumer fireworks.

PHMSA is amending the Hazardous Materials Regulations (HMR) to make miscellaneous amendments to update and clarify certain regulatory requirements. These amendments promote safer transportation practices, eliminate unnecessary regulatory requirements, address a petition for rulemaking, incorporate a special permit into the HMR, facilitate international commerce, and simplify the regulations. These amendments also update various entries in the Hazardous Materials Table (HMT) and corresponding special provisions, clarify the lab pack requirements for temperature-controlled materials, and require hazmat employers to make hazmat employee training records available upon request to an authorized official of the Department of Transportation (DOT) or an entity explicitly granted authority to enforce the HMR.