NW Natural & Pipeline Safety

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1 NW Natural & Pipeline Safety We Grew Up Here NW Natural is an Oregon-based utility company founded in The company purchases natural gas for its core market in western Oregon and southwestern Washington, serving 600,000 customers. NW Natural operates 500 miles of transmission lines and nearly 20,000 miles of distribution lines, including 12,000 miles of mains and 8,000 miles of service lines, to deliver gas to its customers. The company s top priority is to provide safe and reliable delivery of natural gas to our customers. Designing, Building & Operating a Safe Pipeline Since installing its first transmission line in 1956, NW Natural has successfully designed, constructed, owned, operated and maintained more than 500 miles of transmission pipeline. NW Natural has never had a transmission line failure because of its systematic approach to pipeline safety: design it right; build it right, and operate/maintain it right. Design it right means NW Natural follows the federally mandated pipeline safety code, 49 CFR Part 192, and commonly designs and builds pipelines to specifications that exceed regulatory standards. Incorporating Extra Pipeline Safety Measures The U.S. Department of Transmission has developed minimum pipeline safety regulations that are based upon industry best practices. NW Natural utilizes these regulations and in many cases the NW Natural design exceeds the regulations when we have an opportunity to enhance public safety. A partial list includes: increased pipe wall thickness, higher strength material specifications, 100 percent radiographic weld examination, increased pipe depth, increased hydrostatic test pressure and an increased number of valves. Quality Assurance After a transmission pipe is manufactured, the mill conducts several tests to determine the physical characteristics of the pipe (e.g. tensile strength, yield 1

2 strength and ductility). The pipe is filled with water and pressurized to test its integrity, a process called hydro testing. The mill certifies each piece of pipe, indicating the chemical composition of the pipe and verifying its strength. That information is kept for the lifetime of the pipeline. A full-time inspector hired by NW Natural examines each piece of pipe as it is manufactured, verifying the pipe s quality. Any piece that doesn t meet specifications is rejected. Build It Right Certified welders are tested before they begin welding on the pipeline, and inspectors witness every weld that is completed. Although the code requires random evaluations of 15 percent of the welds during construction, NW Natural chooses to x-ray 100 percent of the welds to verify their integrity. Once placed in the ditch, the transmission pipe is padded, using either sand or clean native soil to make sure the pipe coating isn t damaged in the backfill process. In wet areas, weights are placed on the pipe to keep it from becoming buoyant. Another measure taken during construction to prevent future third-party damage is the installation of a warning tape about two feet above the pipe, stating Natural Gas Pipeline Below, Don t Dig Anymore, Call NW Natural Gas. Maintain it Right NW Natural has ongoing leakage inspection, corrosion control, damage prevention, and landslide mitigation programs to ensure safety once the pipe is installed and operating. Twice a year, company crews walk every foot of the pipeline once with an electronic leakage detection instrument that can detect natural gas at extremely low concentrations (parts per million) and once to look for physical changes in the pipeline alignment, including landslides. Transmission lines receive two additional aerial inspections to detect changes along the alignment. A cathodic protection system, which includes placing an epoxy coating on the pipe in conjunction with an impressed electric current, protects the steel pipe from corrosion. Test stations along the pipeline allow NW Natural to monitor the effectiveness of the pipelines cathodic protection system. This system is inspected six times per year. On-site chromatographs allow the composition of the gas to be analyzed to ensure the quality of the natural gas. NW Natural does not transport gas that is corrosive or contains excessive moisture. 2

3 As an extra measure against third party damage, NW Natural routinely supervises construction when a contractor is working near a transmission line to make sure that excavation activity does not threaten the line. Through its landslide mitigation program, the company reviews its entire system and identifies sites that could potentially pose risks to the pipeline. Based on a geologist s on-site analysis and recommendations, remedial action is taken. Changes can be simple, such as improving drainage, or more complex, such as rerouting the pipeline. Control room employees monitor the pipeline system 24 hours a day, seven days a week, checking real time flow rate, pressure and temperature information. Pipeline Failure Case Studies There have been three recent pipeline failures in other states that have caused concern. NW Natural s design, construction, operation and maintenance practices are developed to prevent the circumstances that led to these tragedies. 1. In Carlsbad, New Mexico, corrosive gas caused corrosion inside the pipe, resulting in a pipeline accident. NW Natural does not transport corrosive gas in any of its pipelines. 2. In Bellingham, Washington, an accident occurred on a liquid petroleum pipeline after the line incurred unreported third party damage. Additionally, there were operator errors that contributed to the accident. NW Natural routinely supervises construction when a contractor is working near a transmission pipeline to prevent third party damage. A new Operator Qualification Program (see details below) will ensure that control room operators are highly skilled at responding to situations such as the Bellingham accident. It is important to note that liquid petroleum collects on the ground and in water, while natural gas dissipates harmlessly into the air. 3. A pipeline accident in Edison, New Jersey, was also caused by illegal activities and unreported third party damage. NW Natural is strongly committed to an aggressive, proactive third party damage prevention program. To protect against future operator errors, the Federal Office of Pipeline Safety is requiring companies operating pipelines to adopt an Operator Qualifications Program. NW Natural has identified safety sensitive tasks that are performed on its pipeline system. Employees are evaluated on those tasks and qualify to perform them. They are retested periodically to make sure they are performing tasks correctly. 3

4 Steel Bridge Train Accident On the evening of December 14, 1999 a train derailed at the west end of the Steel Bridge and damaged a natural gas pipeline. Natural gas escaping from the damaged pipeline ignited near the bridge. The fire was not caused by a natural gas pipeline failure, but rather by damage resulting from the train derailment. A subsequent investigation of the incident found that the derailment was due to procedural error on the part of the railroad operator. The derailed freight cars hit a natural gas pipeline valve that had been in the same location without incident since Company personnel coordinated with fire personnel at the scene and were assured that the fire was under control. Operations and planning personnel carefully reviewed system maps to develop a shutdown plan to stop the flow of gas to the fire without creating a greater safety risk by interrupting gas service to thousands of customers (including critical service customers such as hospitals and nursing homes). NW Natural coordinated closely with other emergency response agencies in responding to the train derailment incident. There were no serious injuries, property damage was minimal, and gas service was temporarily interrupted to three residential customers in an adjacent apartment complex. Going the Extra Mile In 1985, NW Natural initiated a cast iron replacement program, the first of its kind in the country. The program, which the federal Office of Pipeline Safety later described as a model for the industry, spent $70 million to replace the cast iron pipes during a fifteen-year period. The cast iron pipes dated to the early 1900s and were replaced with modern materials of polyethylene pipe or corrosionresistant coated steel, which have a life expectancy of more than 100 years. In 2001, the company initiated a $75 million bare steel replacement program. All bare steel mains and services will also be replaced over the next 20 years with polyethylene pipe or corrosion-resistant coated steel. These are not programs required by regulatory agencies, but along with the geo-hazard program created in 1999, are voluntarily initiated by the company to ensure maximum public safety. A Leader In Safety NW Natural is associated with several national associations, including the Western Energy Institute, and the American Gas Association, and it is at the forefront of developing gas industry best practices. The company has a staff of 4

5 registered professional engineers, a registered geologist and specially trained corrosion experts working to ensure the integrity of its pipeline system. An active participant in improving pipeline safety and reliability, NW Natural was a leader in creating Oregon s first true One-Call Center and the current statewide Oregon Utility Notification Center. The One-Call center helps prevent third-party damage (the biggest threat to pipeline safety) by acting as a single point of contact for excavators to notify underground facility owners of upcoming construction excavation. Facility owners then mark the location of underground utilities. During NW Natural s 146-year history, the company has earned an outstanding pipeline safety reputation. NW Natural has never experienced an accident resulting in hospitalization or a fatality on an operating transmission line. The company continues to initiate new pipeline safety programs and has been a key participant in a number of innovative programs that have substantially improved safety for the company and for underground utilities statewide. Nationwide, the natural gas industry operates and maintains a network of more than 1.7 million miles of transmission and distribution pipelines. The distribution system serves the heating, cooking and process needs of more than 60 million residential, commercial and industrial customers in the United States. Natural gas pipelines transport 25 percent of the nation s energy requirements through an infrastructure that has proven to be exceptionally safe, reliable and efficient. According to statistics provided by the U.S. Department of Transportation (D.O.T), natural gas transmission lines are the safest mode of transportation. Over the past 10 years, according to D.O.T data, natural gas use has increased by 23 percent. During that time, the number of accidents has decreased by 38 percent. This has been accomplished by an industry-wide focus on safety, not only for natural gas customers and workers in the industry, but also for the public at large. The industry s outstanding safety record is supported by extensive pipeline safety programs under the jurisdiction of state and federal pipeline safety officials. The industry is constantly working to improve its excellent safety record even further. 5