Natural Gas, Propane, LNG and Hazardous Liquid Intrastate and Interstate Operators


Intrastate Gas Distribution

Duncan Rural Services Corp.

Graham County Utilities

Southwest Gas Corp.

UniSource Energy Services Inc.


Intrastate Gas Transmission

Abbott Nutrition

Arizona Public Service

Calpine Pipeline Co.

Gila River Power, LLC

Mineral Park Mine

Nucor Steel Kingman

Pimalco Aerospace Aluminum

Zapco (Biogas Energy Tactics)

Interstate Gas Transmission

El Paso Natural Gas Co., LLC

Mojave Pipeline Operating Co.

North Baja Pipeline, LLC

Questar Pipeline Co.

Southwest Gas SGTC

Transwestern Pipeline Co.




City of Benson

City of Mesa

City of Safford

City of Willcox

Colorado City

Intrastate Propane (LPG)

Alliant Gas Arizona Propane LLC

Copper Market Gas

Ikard & Newsom Propane

Tuba City USD No. 15

Valle Airpark

Interstate Hazardous Liquid

Kinder Morgan Energy Partners, L.P.

Intrastate Liquefied Natural Gas (LNG) 

Applied LNG Technologies

Desert Gas Services, L.P.

Intrastate Hazardous Liquid

Arizona Public Service

Plains LPG Services, L.P.

Swissport Fueling, Inc.

What government agencies are responsible for regulating gas and hazardous liquid pipelines in Arizona to ensure public safety and system reliability?
The Arizona Corporation Commission (ACC) has authority under state law to oversee the construction, operation and maintenance of intrastate pipelines – basically those pipelines that begin and end within Arizona’s borders, such as those operated by Southwest Gas Corporation, UniSource Natural Gas, and various municipal systems. The ACC exercises its authority over these and other intrastate pipeline operators by administering and enforcing Arizona’s Pipeline Safety Rules (

This is the primary function of ACC’s Pipeline Safety Section, which in accordance with the rules, conducts regular inspections of intrastate systems and also performs specialized and construction inspections. If Pipeline Safety Section inspectors discover a safety violation, the staff can take the necessary steps to see that the violation is corrected – up to and including recommending fines against the operator.

Under federal pipeline safety laws, the United States Department of Transportation (US DOT), Office of Pipeline Safety, has exclusive regulatory authority over pipelines that are defined as interstate pipelines – those pipelines used to transport gas and hazardous liquids across state lines throughout the nation.

In Arizona, interstate pipelines include natural gas facilities operated by El Paso Natural Gas/Kinder Morgan, Questar and Transwestern, and liquid fuel lines operated by Kinder Morgan Energy Partners. Federal pipeline safety laws preempt any state from regulating interstate pipeline safety. Accordingly, only the US DOT may impose sanctions against interstate operators for violating federal pipeline safety regulations.

If the US DOT’s Office of Pipeline Safety has exclusive jurisdiction over interstate pipeline safety, why does the ACC’s Pipeline Safety Section inspect interstate pipelines?
The US DOT Office of Pipeline Safety has authorized the ACC’s Pipeline Safety Section to perform the required federal inspections and audits of interstate operators with facilities in Arizona. This delegated authority and our ability to perform these inspections for the federal office requires that we adhere to specific conditions and terms contained in an agreement (Interstate Agent Agreement), which may be renewed annually. When we find a potential or probable violation of federal pipeline safety standards, we submit a report with recommendations to the US DOT regarding enforcement action. It is then up to the federal office to enforce the federal laws governing pipeline safety.

The ACC’s pipeline safety program continues to be one of the most highly-regarded state pipeline safety offices in the country, receiving a maximum score of “100” on the majority of its annual certifications from the US DOT office since 1995. In addition, ACC’s Pipeline Safety Section staff are often called upon to assist with federal and state operator training programs.

How can I find out more about the US DOT’s Office of Pipeline Safety?
The federal Office of Pipeline Safety maintains a very helpful website with links to pertinent regulations and detailed information about the office and its responsibilities. View the website at

How can I find out if there is a hazardous liquid or natural gas pipeline near my home, office or a property I am interested in purchasing?
As a joint government-industry effort between the US DOT’s Office of Pipeline Safety, other federal and state agencies, and the pipeline industry, the National Pipeline Mapping System (NPMS) is a database that contains the locations and selected attributes of natural gas transmission lines, hazardous liquid lines and other related facilities. You can go online to and click on “Find Out Who’s Operating Pipelines in Your Area” to input your county or zip code. The database will provide you with contact information so you can learn more from the pipeline operator.

The NPMS is created from mandatory submissions of pipeline and LNG facility data by pipeline operators. The NPMS National Repository is responsible for collecting, processing, and building a national seamless pipeline database from the submitted data.

This website serves to provide up-to-date NPMS information to federal and state governments, the pipeline industry and to the public. By filling out an application on this same website, state and local governments and emergency response personnel can apply for password-protected access to more detailed information through the NPMS system.

How may I obtain copies of inspection reports?
Inspection reports for intrastate operators are state records and can be requested from the ACC. These reports become final once the report is submitted to the pipeline operator. Simply make your request in writing under the Arizona Public Records Act, referencing ARS Sections 39-121 et seq. To help us respond effectively to your request, please provide as much information as possible specifying the type of information you are requesting and the time period you wish to be covered. Please provide a phone number and contact person in case we have questions as we begin fulfilling your request. Although it is not required, stating the reason for your request would be helpful as we may know of additional information that could be valuable to you. Intrastate public records requests should be sent to:

Arizona Corporation Commission
Pipeline Safety Program Manager
1300 W. Washington Street, Suite 220
Phoenix, Arizona 85007

Phone: (602) 262-5601
Fax: (602) 262-5620

All records relating to inspections or investigations of interstate natural gas or hazardous liquid pipeline facilities are the property of the United States and are subject to federal law. The ACC’s Interstate Agent Agreement requires that requests for federal pipeline safety records must be deferred to the US DOT Office of Pipeline Safety. In making such requests, we recommended that you specify that the request is being made according to the federal Freedom of Information Act (5 USC 522), and that you address the request to:

U.S. Department of Transportation
Pipeline and Hazardous Materials Safety Administration
1200 New Jersey Avenue, S.E.
Washington, DC 20590-0001

Phone: (202) 366-4595