OVERTURNED TANKER THREATENS UNDERGROUND UTILITIES

BY STEVEN M. DE LISI

On January 15, 1999, at 12:44 a.m., the Virginia Emergency Operations Center (VEOC) received a request for assistance from the hazardous materials coordinator for Louisa County. Emergency response personnel from that locality and neighboring Orange County were on the scene of an overturned cargo tank trailer (MC-306) on a two-lane road leading to Gordonsville Energy Limited Partnership (GELP), a local electric generating facility. Weather conditions at the time of the incident included periods of rain, sleet, and light snow.

The tanker, which contained 7,500 gallons of diesel fuel, was resting on its right side along the road shoulder. Complicating this scenario was that the vehicle was lying across a creek, which had been fed by large volumes of storm water runoff from the town of Gordonsville. Only minor leakage was detected from the cargo tank’s dome covers, and fire department personnel had placed absorbent booms downstream of the incident site. The driver was uninjured and escaped from the vehicle unassisted.

The VEOC immediately contacted the assigned state hazardous materials officer from the Virginia Department of Emergency Management (VDEM). Following a brief discussion with the local haz-mat coordinator, the haz-mat officer responded and then requested the assistance of the nearest state regional haz-mat response team, the Henrico County Regional Hazardous Materials Response Team. This team was on-scene within one hour.

UNDERGOUND UTILITIES

Suspecting that the road shoulder on which the vehicle had come to rest was a likely site for the presence of underground utilities, the haz-mat officer also contacted “Miss Utility” (the Virginia One Call notification center) to request assistance in locating any of these facilities that may be in the affected area. This call for assistance went out at approximately 1:30 a.m.

This request was critical for the following reasons:

  • The potential for the release of large amounts of the cargo (diesel fuel) could likely contaminate underground utilities, such as communication cables.
  • The impact of the vehicle’s striking the ground may have damaged underground utilities.
  • Efforts to upright the vehicle from the road shoulder, which was soft because of the wet weather conditions, could cause the vehicle to settle and contact underground utilities.
  • Placement of ground rods, which can be used during product transfer to effectively control the generation of static electricity, could contact and damage underground utilities.

The Miss Utility operator immediately determined that the following utilities were located at or near the accident site:

  • Transco Pipeline;
  • Williams Communications;
  • Columbia Gas of Virginia, Inc.;
  • Bell Atlantic;
  • Central Virginia Electric Co-op; and
  • Virginia Power.


A view of the pipeline after it was exposed by Columbia Gas of Virginia, Inc. employees. The pipeline appears as a yellow tube just to the left of the shovel.

While en route to the scene, the haz-mat officer spoke with representatives from Transco Pipeline and Williams Communications by mobile telephone and learned that their utilities were not close enough to the accident site to be affected. However, an employee of a contract utility locating company, All Clear Locating Services, Inc., contacted the haz-mat officer and informed him that there could be other underground utilities in the immediate area. All Clear Locating Services, Inc. was under contract to locate underground service for the remaining utilities listed earlier; their representative agreed to respond to the scene.

THE ACTION PLAN

By 3:30 a.m., lead representatives from all emergency response agencies involved in the incident were attending a unified command briefing session. Included were the haz-mat officer, regional haz-mat team commander, the local fire chief (who served as the incident commander), and the All Clear Locating Services, Inc. employee. During this meeting, it was confirmed that a high-pressure natural gas pipeline belonging to Columbia Gas of Virginia, Inc. was located directly beneath the overturned vehicle. The facility was a 12-inch steel distribution pipeline operating under approximately 450 psi and designed to operate under a maximum allowable operating pressure of 1,000 psi. Service was dedicated to Gordonsville Energy.


The relationship between the underside of the tractor chassis and the underground natural gas pipeline. The pipeline is identified by the upright marker pole and the yellow flags (lower right-hand corner) placed by the utility locator. (Photos by author.)

Prior to the briefing session, the locator from All Clear Locating Services, Inc. had been able to estimate the horizontal position of the pipeline. However, no information was available on the depth of the line. Concerns regarding the line depth were heightened since the damaged vehicle had partially sunk into the soft road shoulder as a result of the rainy conditions. It was decided to immediately contact Columbia Gas of Virginia, Inc. and await the arrival of its representatives before attempting any further activity at the site.

At approximately 5 a.m., personnel from Columbia Gas of Virginia, Inc. arrived on-scene. Based on their recommendations, it was decided to begin operations to transfer the product to lighten the load. It was also decided that employees of Columbia Gas of Virginia, Inc. would dig examination holes on either side of the crash site to learn the exact depth of the pipeline. Workers later determined the pipeline’s depth to be 58 inches near the tractor and 38 inches at the rear of the trailer.


The tractor and trailer as they rested on the road shoulder. The creek, which had been fed by storm water runoff, can be seen flowing under the trailer.

All product transfer and vehicle recovery efforts were conducted according to the established action plan and were completed by 1 p.m. of the same day with no negative impact to the pipeline.

LESSONS LEARNED AND REINFORCED

Lessons reinforced during this operation included the following:

  • Utility company representitives are important stakeholders in the decision-making process during this type of incident. It is essential that you have on file the names of and a means of reaching the appropriate contact individuals outside of normal working hours.
  • Knowing the location of the high-pressure natural gas pipeline provided emergency responders with valuable data when preparing their action plan. Damage to this type of facility can present a significant safety hazard to personnel and can potentially seriously disrupt utility distribution systems.
  • Remember that site hazards exist not only around you and above you, but below you as well!

STEVEN M. DE LISI has been a hazardous materials officer with the Technological Hazards Division of the Virginia Department of Emergency Management since 1997. Previously, he had served as a regional training manager for the Virginia Department of Fire Programs and as training officer, a lieutenant, and a member of the haz-mat team for the Newport News (VA) Fire Department. He has an associate’s degree in police science and a bachelor’s degree in governmental administration.

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