Unearthing the Facts About Pipeline Safety
We can’t usually see them, but our lives depend upon them. Nearly two and half million miles of them crisscross the nation underneath our feet. They transport most of the natural gas, gasoline, crude oil, and other petroleum products that we use every day. And while they’re the regarded as the safest means of transport, they can cause tremendous disasters if they’re damaged.
They’re pipelines, and they supply about two-thirds of the energy America uses. A network of just under half a million miles of transmission pipelines moves large quantities of products from where they’re found to where they’re processed, aided by compressors and pumps along the way. After they’re readied for our use, many of those products then flow through part of a two-million-mile network of distribution pipelines that include the gas lines that service our homes.
The National Transportation Safety Board’s statistics confirm that pipelines offer the safest transportation of natural gas and petroleum (and yes, pipelines are classified as a form of transportation, along with vehicles, trains, ships, and aircraft). Pipeline accidents are comparatively rare, but when they do happen, they tend to be spectacular.
One of the biggest causes of pipeline accidents is damage caused by excavation in the immediate area or compression of the ground above the pipeline by heavy equipment or materials. That’s why it’s important for construction crews to become familiar with pipelines and the safety procedures associated with working near them.
The safety zone
Before a pipeline is constructed, its owners must obtain the right to place it. Typically, pipeline companies do not own the land under which their pipelines are installed. Instead, they obtain what are known as easements, which are documents giving them permission to place the pipelines under private property,
Easements generally cover more than just the ground immediately about the pipeline’s diameter. To designate a safe area around the pipeline and ensure access for any needed maintenance, easements provide for a right-of-way on either side of the pipeline. At times, rights-of-way may be obvious to construction crews, as they’re often in the form of narrow strips of land that are clear of trees and structures. In some cases, rights-of-way may be marked with posts or signs that include the pipeline owner’s name and contact information, but they aren’t always present.
To protect pipelines from damage and reduce the potential for disaster, pipeline companies and public utilities participate in damage prevention programs. The programs serve as a clearinghouse for records of underground pipelines and utilities, giving construction crews a single source for information about all of the underground infrastructure that may run through a piece of property.
In most states, crews are required to call the prevention programs before performing any type of excavation work anywhere that underground utilities might be present. Usually, one call to 811 is all it takes to start that process. The prevention program will send someone out to the worksite to mark all of the known pipelines and other underground utilities.
Those markings are color-coded, and it’s important for crews to recognize what each color means. For example, red markings signal the location of underground electrical lines, cables, and conduit. Yellow markings are used for natural gas, petroleum products, and steam lines. Orange markings are for communication lines or cables, blue ones for drinking water supplies, and green markings are for sewers and drains.
Generally, if a construction crew has called the prevention program and the worksite has been marked, the contractor will not face any liability if the crew breaches or damages a line that hasn’t been properly marked. However, if an underground utility that has been marked is damaged, or if the contractor fails to call the prevention program and damages the utility, the contractor will be liable for repair costs and damages.
Because some pipelines have signs or markers indicating their approximate location, crews may mistakenly believe that they don’t need to make the call to have the site marked. That’s a dangerous approach, because those signs or markers may not be located exactly over the pipes. They also don’t provide any clues as to depth of the pipeline or other underground service. Sometimes, pipelines or conduits may curve to avoid obstructions or to compensate for soil conditions. Calling 811 is always the safest course of action.
Suspect a leak?
If a pipeline or other underground utility line has been damaged, even if the contractor did not cause the damage, it’s dangerous to be in the area. Leaks can often be detected by the senses. There may be a sharp gaseous smell an oily odor. (Natural gas is actually odorless when removed from the earth. The familiar “gas” smell is the result of adding an odorant to the gas.) Crews may hear a hissing sound from small leaks or a roaring sound from larger ones. They may notice pools of liquid or bubbling on the ground, or vapors coming from the ground.
When anyone believes that there may be a leak, work should stop immediately, and all the workers should leave the area and move upwind. Be sure to turn off any equipment that could be an ignition source. Call 911 or the local first responders and let them deal with the situation.
Never try to fix a leak on your own. Pipelines often operate under high pressure, and the potential for serious injury is significant. In addition, fumes or vapors may be toxic. Leave the work of dealing with the leak to the trained professionals. And don’t resume work until the professionals have given everyone the all-clear.