Aquila Gas Pipeline - Elk City Gas Processing Plan - Executive Summary
Aquila Gas Pipeline Corporation (Aquila) owns and operates a natural gas processing facility, the Elk City Gas Processing Plant, in Beckham County, Oklahoma. The plant is designed to process natural gas and recover liquid products from natural gas by physical separation and cryogenic means. Both petroleum condensates and natural gas liquids are recovered from the inlet pipeline gas in this process for off-site sales. |
Section 112(r) of the Clean Air Act applies to the Elk City Gas Processing Plant because the plant handles and stores methane, ethane, propane, butane, isobutane, pentane, and isopentane in excess of threshold quantities. Two requirements of this section specifically apply to operations at the plant:
1. '112(r)(1) - Purpose and General Duty Clause - The essence of the general duty clause is that an owner/operator that stores and uses hazardous chemicals in any quantity has a fundamental obligation to ensure a safe operation and to have plans in place in the event of
an accident to appropriately manage the situation. Aquila is committed to ensuring the safe operation of the Elk City Gas Processing Plant, as well as all of its other operations, to ensure a safe workplace for our employees and a safe location for our neighbors in the community. Aquila, therefore, has procedures in place to prevent accidents and is committed to emergency preparedness both for our facility and community-wide by coordinating with the Elk City Fire Department.
2. Risk Management Plan - The Elk City Gas Processing Plant processes natural gas, recovering natural gas liquids and producing pipeline quality natural gas. This process involves the handling and storage of chemicals in excess of thresholds specified in '112(r). Even prior to the promulgation of '112(r), Aquila management has been very aware of the potential hazards posed by the handling and storage of natural gas and natural gas liquids. Programs have been established to prevent any accidental releases and t
o train personnel for emergency response in the event of a release. These programs are documented and described in this Risk Management Plan.
For planning purposes, Aquila has considered the impact of a "worst case" accident, defined to be a 30,000 gallon release from the Y-Grade product tank resulting in the instantaneous formation of a vapor cloud which explodes. Using the National Oceanic and Atmospheric Administration's (NOAA's) RMP*Comp methodology, a potential radius of impact due to the explosion was calculated to extend to 0.33 miles. Demographic information based on the 1990 census indicates that 10 people live within this radius. It should be emphasized that the probability of the worst-case catastrophic event evaluated in this report is extremely remote - far less than natural catastrophes such as tornadoes and floods that could produce much more severe and extensive damage and injury. A consideration of the 0.33-mile radius has been incorporated into our notification a
nd emergency response planning.
Aquila also considered the impact of a more likely release. This alternative release is characterized as an accident during loading of liquids from a truck into a condensate storage tank at the site. If the truck driver failed to disconnect the transfer hose prior to departure, plant piping and equipment could potentially be damaged, resulting in a release of a mixture of natural gas liquids under pressure. The duration of this release could be up to ten minutes, based on the time needed to close valves. Using RMP*Comp, the impact distance of a potential explosion of the vapor cloud formed after this release was calculated to be 0.31 miles. No schools, churches, and parks are located within this radius.
Aquila has implemented safety precautions and procedures designed to prevent and mitigate catastrophic releases. Aquila has active operating, maintenance, training, and inspection procedures. Aquila provides annual emergency response training to it
s employees. In addition, Aquila has coordinated with local emergency responders including the Elk City Fire Department and the Local Emergency Planning Committee.
Aquila's management is committed to the following:
- Preventing accidents;
- Training our employees in correct response procedures in the event of an accident;
- Participating in community emergency preparedness;
- Addressing any citizen concerns by fully explaining potential hazards associated with Aquila operations and all steps being taken to prevent and mitigate accidents; and
- Being a good corporate citizen of Beckham County.
With these objectives in mind, this Risk Management Plan has been developed to provide information about our management of the risks associated with the natural gas treatment and liquids recovery process. Most important, we stress our commitment to ensuring a safe operation for our employees, our visitors, and our community.