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Keynote Address for the Damage Prevention Convention, Atlanta, Georgia
Jim Hall
Damage Prevention Convention, Atlanta, Georgia

Good morning. It’s a pleasure to be with you today to discuss an issue of great importance to the National Transportation Safety Board – excavation damage prevention. This issue is on the NTSB’s list of most wanted safety improvements.

While pipeline accidents result in fewer fatalities annually than accidents in the other modes of transportation, a single pipeline accident has the potential to cause a disaster that can kill dozens of people and injure hundreds, and cost millions of dollars in property damage, community disruption, ecological damage and insurance liability.

Most Americans have no idea about the scope of our nation’s pipeline industry, or of its importance to our economy. Pipelines carry more hazardous materials in the United States than any other form of transportation. Annually, almost 600 billion ton-miles of hazardous liquids are carried in 177,000 miles of pipe, and more than 21 billion cubic feet of natural gas are delivered through 1.2 million miles of pipe.

With communities continuing to expand into areas that once were open fields, many major transmission pipelines now are located amidst neighborhoods whose residents are unaware of their presence. New construction in this country continues to rise, with the latest figures according to the Census Bureau showing $520 billion of construction in 1997, up almost 9 percent in just two years. New construction means new gas lines, new water lines, new fiber optic cable and new cable television. Any of these projects expose lines already in the ground, and lead to what is the single most common cause of pipeline accidents, excavation-caused damage.

The Board first addressed this issue thirty years ago when on January 8, 1968, in Reading, Pennsylvania, a crew using excavation equipment to repair a water leak struck a gas service line. The resulting explosion killed all 9 occupants of a house.

While excavation damage is the largest single cause of pipeline accidents, it ironically is almost entirely preventable. The frequency of such accidents convinced the Safety Board that excavation damage prevention should command greater attention.

As a result, last December the Safety Board released a major study on this issue called Protecting Public Safety Through Excavation Damage Prevention. Joining me here at this conference is our Deputy Director of Pipeline Safety, Rod Dyck, who has available for you copies of this report and all other reports I speak about today. In addition, these reports can be found on our web page at

In our study, we discussed three major subject areas:

    • Essential elements of an effective excavation damage prevention program.

    • Accuracy of information regarding buried facilities, and

    • System measures, reporting requirements and data collection.

Let me discuss these in turn. While there are many elements to an effective excavation damage prevention program, I’d like to highlight a few:

    • Mandatory program participation by all affected parties;

    • Excavation Marking;

    • Effective training; and

    • Effective enforcement.

One of the most obvious examples of the need for mandatory participation is the "One Call" system. The NTSB has been at the forefront of encouraging the use of "One Call" systems, recommending them as early as 1973. When implemented properly the One Call system is an excellent way to ensure that all existing facility lines within an excavation area are marked so that the excavation company can plan its dig to avoid hitting any lines.

The importance of participation in the One Call system was once again proven on May 23, 1996. In Gramercy, Louisiana, a 20-inch gasoline pipeline ruptured, releasing about 475,000 gallons of gasoline into a marsh land and the Blind River, causing environmental damage and killing fish, wildlife, and vegetation.

The investigation revealed that about 8 months earlier an excavator made a substantial dig over the pipeline rupture site without using the Louisiana One-Call System. The Safety Board determined that the probable cause of the accident was the failure of the excavator to take adequate measures to ensure that its excavations did not damage the pipeline or to notify the pipeline operator that its excavations may have damaged the pipeline.

State One-Call programs are intended to protect all facilities. However, our study found that all but seven States granted exemptions to a variety of organizations such as State transportation departments, municipalities, railroads, mining operations, water utilities, military bases, and Native American lands.

Think about that. How can a One Call system effectively work if the parties necessary for effective damage prevention are exempted from participation? The failure of all parties to participate in damage prevention programs substantially undermines the effectiveness of the programs at the expense of public safety.

In addition to public safety interests, the Board is concerned that taxpayers ultimately bear the burden for these exemptions by paying for the cost of fixing excavation damage. Because of the number of exempted State transportation department activities, the Safety Board recommended that the Federal Highway Administration should require these departments to participate in excavation damage prevention programs and consider withholding funds to States if they do not fully participate in these programs.

The Board recommended that the Research and Special Programs Administration (RSPA) host jointly with the NTSB at regular intervals workshops on excavation damage prevention. On October 21, Congress completed action on the Omnibus Appropriations Bill. Included in that legislation was $400,000 earmarked for One-Call public education. As part of that education effort, the NTSB and RSPA have been directed to conduct a new joint public meeting on One-Call systems.

Another element of a successful damage prevention program is effective training. The diversity of the training needs presents the greatest challenge. Since 1987, the Safety Board has advocated that RSPA develop requirements to ensure that operators of pipelines establish employee qualification, training, and testing programs. While I am happy to see that RSPA recently proposed a rule in this area, I am not happy that it has taken them a decade to reach this point.

The need for quality excavation training programs was evident on November 21, 1996 when an explosion occurred in San Juan, Puerto Rico that resulted in 33 fatalities and 69 injuries – the deadliest pipeline accident ever investigated by the Safety Board. The explosion destroyed the first, second and third floors of a six story building and severely damaged the rest of the building. Adjacent buildings and businesses were also extensively damaged by the blast.

During the investigation, the Safety Board found several events that led to the accident, but I will limit my comments to those pertinent to the issue of excavation damage. We found a cracked and leaking 1-1/4 inch diameter plastic pipe close to the exploded building. Digging deeper, we found a 16-inch diameter water pipeline under the cracked plastic pipe, which had been installed after installation of the plastic pipe. Differential settlement resulting from inadequate support under the plastic pipe apparently generated long-term stress that led to the formation of the crack.

This deadly pipeline accident may have been avoided had proper precautions been taken to protect the plastic pipeline during subsequent excavation activities.

Training to prevent excavation damage to the underground infrastructure should not be limited to the pipeline industry and its operating personnel. Excavators working around pipelines are frequently not under the control of pipeline operators and often have little knowledge of good pipeline practices. They need to be trained and educated about good excavation practices, relevant State laws, and One-Call procedures.

In an effort to ensure that excavators are aware of their responsibilities to protect underground facilities, some States have licensing requirements that assess professional knowledge in this area. Locators also need training to fully participate in the notification process and to understand locator marking symbols. The National Utility Locating Contractors Association has developed standards for structured training for locators. Some underground facility owners require that their locator contractors have this training, and some have auditing programs to help ensure that these standards are met.

I believe all of these programs are steps in the right direction, but we need all persons involved in excavating activities nationwide to be subject to this type of training. Along these lines, the Safety Board has recommended that the American Public Works Association (APWA) review existing training programs and materials related to damage prevention and develop guidelines for distribution to One-Call centers.

Part of any successful excavation training program should focus on another prevention element – excavation marking, which includes pre-marking and temporary marking of underground facilities.

Pre-marking is used to visually mark the physical boundary of an excavation site. By pre-marking the site, excavators can specifically communicate to underground facility owners where they intend to dig.

Temporary marking of underground facilities uses standard marking colors to advise the location of existing facilities. Markings of the appropriate color for each facility are placed over the centerline of the pipe, conduit or cable.

The significance of marking underground facilities was demonstrated on October 23, 1996. A dredge hit and ruptured a 12-inch diameter natural gas transmission pipeline in Tiger Pass, Louisiana. The resulting fire destroyed the dredge and an accompanying tug.

The investigation revealed that, in preparation for the planned dredging, the pipeline operator took inadequate steps to identify and mark the location of its pipeline. There were no permanent line markers showing the location of the transmission pipeline, and the pipeline operator misidentified to the dredging company the location of its pipeline by about 300 feet. A decade earlier, in 1983, RSPA revoked federal requirements for placing and maintaining permanent markers where pipelines cross navigable waterways. Here was an example of where such a requirement might have prevented this accident.

As a result of this accident, the Safety Board recommended that RSPA require pipeline operators to locate and place permanent markers at sites where pipelines cross navigable waterways.

The last of these essential elements that I intend to cover today is effective enforcement. This is a necessity for any effective safety program. We’ve seen too many instances in all modes of transportation in which regulations that address identified safety problems fail because there has been little enforcement to back them up. Several States have found benefits from administrative rather than court enforcement of their regulations. State administrative enforcement can be accomplished on site and does not rely on an Attorney General’s office for execution. Thus, it keeps State pipeline safety actions from being in direct competition with other State priorities.

The list of these elements is by no means exhaustive, but we believe they would go a long way in establishing an effective damage prevention program.

The second major subject area discussed in our study was the accuracy of information regarding buried facilities. All parties have a genuine interest in accurately locating underground facilities, but with current equipment technologies and mapping records, there remains a variety of errors that can potentially affect the ability to positively identify the position of underground facilities.

Mapping has long been an important aspect of data collection and damage prevention. However, current damage prevention programs use many different maps that vary in scale, accuracy, resolution, standard notation and data format. Although computerized automated mapping systems have the potential to coordinate information in a more precise, timely manner, many of these programs are not compatible and it is difficult or impossible to merge records developed over the years by different organizations.

As a result of the 1997 study, the Safety Board concluded that underground facility mapping must consider the amount of detail and the accuracy of information necessary for effective use. The Board recommended that RSPA develop and implement nationwide standards for a common mapping system.

At the same time, the capabilities of locator equipment need to be incorporated into damage prevention practices. More research and testing is needed to determine the accuracy of locating equipment, especially equipment that detects depth. Without accurate information on the location of facility lines, we can implement all of the prevention programs we want and still fail to prevent excavation damage. The Safety Board recommended that RSPA sponsor independent testing of locator equipment performance, see that uniform certification criteria of locator equipment be developed, and determine if State requirements for location accuracy and hand-dig tolerance zones are appropriate with commercially available technology.

Let me address the third major issue of our study, data collection and reporting requirements. Few performance-based measures are available for assessing excavation damage prevention programs. Those measures that are maintained are generally specific to selected States or are maintained by individual companies for a specific underground system.

Measures of underground damage are needed for several reasons:

    • to determine the effectiveness of changes to State damage prevention programs,

    • to evaluate damage prevention practices,

    • to perform risk assessment, and

    • to assess the needs and benefits of training.

Many facility operators, particularly companies that transport gas and hazardous liquids, investigate and record "line hits" in terms of damages per thousand locate requests. Because the risk of excavation damage is associated with digging activity rather than system size, " hits per digs" may be a useful measure of risk exposure. A comprehensive measure of hits per digs tracked over time can be a useful indicator of how well excavation damage prevention programs are performing.

One-call notification centers may be the most appropriate organizations to collect risk exposure data on the frequency of digging and the number of facility hits. But there are many separate one-call systems operating in the United States collecting different information in different formats. To standardize how and what information should be collected, the Safety Board recommended that RSPA and the APWA develop a plan for collecting excavation risk exposure data, and then work with the one-call systems to implement the plan to ensure that excavation exposure data are being consistently collected. The Safety Board also recommended the use of excavation risk exposure data as a tool in periodic assessments of the effectiveness of State excavation damage prevention programs.

The federal government has not done its job in data collection, either. RSPA’s accident report form includes categories of cause of the accident. But these listed categories are designed very poorly. For example, the report form for hazardous liquid pipelines offers just seven categories of cause, from corrosion to outside force damage to other. For 1996, RSPA data indicated that "outside force damage" was the leading cause of accidents. The second leading cause for that year was "other."

Although excavation damage is the leading cause of pipeline accidents, it is not specifically indicated as a category on RSPA’s accident form. Most excavation damage accidents are reported under the category of "outside force damage;" however, many excavation damage reports are alternatively listed as "other" and "incorrect operation by operator personnel." Accident reports that included written narrative descriptions such as "lightening strike," "vandalism," "drilled into pipe," and "bullet hole" also appear in both the "outside force damage" and "other" categories. The Safety Board has pointed out over many years that RSPA’s definitions of accident causes are imprecise and that the distinctions between categories of cause are vague.

This is more than just a paperwork dispute. Deficiencies in RSPA’s accident data precludes effective analyses of accident trends and evaluations of performance. Various subcategories of excavation damage such as whether one-call was used or if mechanical equipment was used close to the locate markings would yield further useful information. The Safety Board recommended that RSPA revise the cause categories on its gas and hazardous liquid pipeline accident report forms to eliminate overlapping and confusing categories and to clearly list excavation damage as one of the data elements, and consider developing sub-categories.

Who should implement effective damage prevention programs? We have recommended that RSPA and APWA conduct detailed and comprehensive evaluations of existing State excavation damage programs and recommend needed improvements, such as requirements for full participation, pre-marking, training, and effective enforcement, for persons involved in excavation activities.

Let me say in closing that during the past 25 years, your industries have worked hard to deliver improved processes and programs for preventing excavation damage to the infrastructure. The States, with your assistance, have enacted new regulations that require early notification of planned excavations, temporary marking of buried facility locations in areas to be excavated, protection of facilities during excavation, and reporting of damages caused by excavation operations.

In addition, education and communication programs are helping to teach the public, excavators, and others about damage prevention and to make notifications easier for excavators. Equipment and technologies for identifying the existence of buried facilities are being improved to provide more accurate facility location information, although more needs to be done. These factors represent the tremendous strides that can be made when the States, federal agencies and the industry combine their efforts to achieve a common goal.

However, our work is not done. Excavation damage is still the leading cause of pipeline accidents. New construction puts our extensive pipeline system at risk every day, and replacing our aging infrastructure poses additional risks to the public. Just last week, a backhoe operator accidentally hit a natural gas line near a house in Hingham, Massachusetts. Although the family was able to leave their house before it exploded, their residence was destroyed.

Prevention plans, standardized procedures and performance measures are only part of the answer. Without the continued cooperation of your industries, the programs currently in place cannot effectively serve their purpose – to prevent accidents, to save taxpayer dollars in clean-up costs and ultimately to protect the public safety.

Although that may seem a daunting task, through forums such as this and through a commitment to get this job done we can develop more effective strategies to prevent accidents and save lives. This isn’t a new frontier; we all agree that these accidents are preventable. It takes the will of regulators and the commitment of industry, both at the management and workforce level, to greatly reduce excavation damage to our nation’s pipeline infrastructure.

Thank you for inviting me to speak to you today.


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