Stiles Gas Plant - Executive Summary

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SAFETY POLICY STATEMENT 
It is the policy of Davis Gas Processing that accident prevention shall be considered of primary importance in all phases of operation and administration. It is the intention of Davis Gas Processing management to provide safe and healthy working conditions and to establish and insist upon safe practices at all times by all employees. The prevention of accidents is an objective affecting all levels of our company and its operations. It is, therefore, a basic requirement that each supervisor make the safety of all employees an integral part of his or her regular management function. It is equally the duty of each employee to accept and follow established safety regulations and procedures. Every effort will be made to provide adequate training to employees. Employees are expected to assist management in accident prevention activities. Unsafe conditions must be reported immediately. Safety is everyones business. 
 
SITE DESCRIPTION 
The Stiles DGP Plant is located 23  
miles North West of Big Lake, Texas. Travel West out of Big Lake, Texas for about 13 miles to Best, Texas, Turn North on  Lease Road for 10 miles to Plant Location. 
There is a Product Propane Storage Tank, which is a 72 barrel painted, welded steel, above ground, horizontal pressure vessel. The  tank operates up to 200 psig and is protected by a pressure relief valve. Liquid flow into this tank is determined by the process operations. Liquid flow out of this tank goes to tank truck loading and is manually controlled. Operating personnel on a daily basis visually inspect this tank. If a spill occurred at this tank, the contents are so volatile that they would evaporate before penetrating the ground to any significant degree. The ground would freeze and contain the propane as it evaporated. 
There is also a Natural Gas Liquids Storage Tank, that is a 175 barrel, painted, welded steel, above ground, horizontal pressure vessel. The tank may operate up to 75 psig and is protected by a pressu 
re relief valve. Liquid flow into this tank is determined by the process operation. Liquid flow out of the tank goes to tank truck loading and is manually controlled. Operating personnel on a daily basis visually inspect this tank. If a spill occurred at these tanks, the highly volatile contents would extensively evaporate before penetrating the ground to any significant degree. 
 
PURPOSE AND GOALS FOR THE STILES DGP PLANT 
EMERGENCY RESPONSE AND ACTION PLAN 
Emergency Response And Action Plans (ERAP) were developed by Davis Gas Processing  for its Stiles DGP Plant located in Reagan County, Texas.  The ERAP was developed to assist the Stiles DGP Plant Foreman in his responsibility to provide skilled and compliant emergency leadership in the event of emergency situations. 
The ultimate goals of the Stiles DGP Plant ERAP are as follows: 
   1.    To provide Stiles DGP Plant employees with emergency prevention training that will allow them to avoid process emergencies by predicting and recognizing  
potentially hazardous situations. 
   2.    To provide Stiles DGP Plant employees with emergency prevention training that will allow them to recognize and assess the consequences of personal actions when working  with equipment containing pressurized,  very cold, highly volatile,  and flammable substances. 
   3.    To assure that Stiles DGP Plant  employees will respond in a safe, prompt, and compliant fashion in the event of unintentional releases of hazardous chemicals in and from the Stiles DGP Plant. 
   4.    To guarantee that all Stiles DGP Plant visitors  will be effectively warned to recognize, avoid, and to escape hazardous situations and guarantee that they will be accounted for and removed from the Stiles DGP Plant in the event of a site emergency. 
   5.    To document that Stiles DGP Plant emergency response efforts were effective,  prompt,  and  professional. 
   6.    To document that Stiles DGP Plant emergency response training is provided periodically and in a clear and consistent manner, and to e 
nsure  Stiles DGP Plant  employees have a basic working knowledge of Stiles DGP Plant emergency response procedures. 
   7.    To document that Stiles DGP Plant  employees have a clear understanding of the recommended responses for various possible emergency scenarios. 
The Emergency Response Program that we have in place details emergency escape procedures and route assignments that have been posted in work area, and all employees have been trained by supervisors in the correct procedures to follow. New and change in status employees have been trained when assigned to perform any duties that involve the handling of hazardous chemicals.  This facility has an Emergency Shut-Down Procedure that describes the steps to be taken in order for normal operations to be stopped and utility service to be cut off as personnel evacuate the premises during emergency situations.  The Foreman is responsible for accounting for all employees, personally or through a designee, by having all employees report to  
predetermined, designated rally point and conducting  a head count. Rescue and medical duties will be performed by EMS personnel from the Big Lake, Texas Fire Department. The employees of the facility will be notified by verbal notification if  an evacuation is necessary.  All personnel have been trained in the safe and orderly emergency evacuation of the premises. The training includes, but is not limited to, the Emergency Shut-Down Procedures, escape routes, exits, and rally points. Training was and/or will be provided for employees when: 
1.  The plan was initiated 
2.  Responsibilities change 
3.  Employees are hired or transferred. 
 
WORST-CASE RELEASE SCENARIO AND THE ALTERNATIVE RELEASE SCENARIO 
The worst-case scenario would involve some sort of mechanical object (e.g. plane, vehicle) to hit or rupture the storage tanks of either the Natural Gas Liquid Storage Tank or the Propane Storage Tank. 
The Natural Gas Liquid Storage Tank contains 31,000 lbs.  and the Propane Storage Tank co 
ntains 12,600 lbs. of flammable substance with a worst-case scenario radius of exposure of 1,584 feet. The only house in the radius is the foreman of the plant.  
The alternative release scenario could be caused by the following items: 
a)  Compressor or Pump piping failure due to vibration fatigue, packing failure and excessive pressure. 
b)  Pressure vessel gage glass breakage. 
c)  Control and block valve packing failure. 
d)  Pressure relief valve failure due to failure to open or stuck open. 
e)  Cold brittle metal fracture. 
In many of the direct chemical release scenarios, it is relatively easy to forecast where the release will evolve.   Using the RMP Comp. Program on figuring the radius of exposure. With a 2 inch opening and 6 feet above the opening is the fluid level in the tank. The rate of flow would be 316 lbs. per min. and will take about 70 min. to drain the contents of the tank. The radius is 1,056 feet and will incorporate the foremans house only. The Attached Executive Summ 
ary has a diagram that shows the layout of the plant and the house in the radius of exposure. No public facilities or other housing is in the exposed radius. 
 
This facility has had no accidents involving a regulated chemical in the last five years, that has involved death, injury, or emergency response. Our facility has procedures coordinated with the local response agencies encase of  an accidental release. All storage tanks, vessels and equipment were professionally designed and constructed in accordance with the applicable codes and regulations at the time of fabrication. All tanks, vessels and piping are checked for signs of leakage as a part of the operators daily routine tour of the facility. Annual inspections by supervisory personnel are performed in accordance with the company written procedures. 
The Propane is stored in a 3000 gallon, painted above ground, horizontal welded steel pressure vessel. This vessel operates at a nominal 200 psig and is protected by a relief valve. 
Liquid flow to and from this tank is automatic according to process demands except when a load of propane is delivered into the tank. Operating personnel on a daily basis visually inspect this tank. No dike is installed since the propane would instantly vaporize if a spill occurs and no runoff or penetration would occur. 
The Natural Gas Liquids are stored in two tanks, one is the Product Tank which is a horizontal tank of 1600 gallons capacity. The tank may operate up to 200psig and is protected by a pressure relief valve . The second tank is a vertical, 210 barrel capacity tank which is the storage for Condensate/ water mixture by product of the plant. Liquid flow into these tanks is determined by the process operations. Liquid flow out of these tanks goes to tank truck loading and is manually controlled. Operating personnel on a daily basis visually inspect these tanks. No containment is needed for these tanks, if a spill occurred at these tanks, the contents are so volatile that th 
ey would evaporate before penetrating the ground to any significant degree.  
This facility follows the rules and regulations of  Occupational Safety and Health Administration (OSHA), Department of Transportation (DOT), Environmental Protection Agency(EPA),  and the Texas Railroad Commission(TNRCC).This facility has labeled all their storage tanks with identifying signs and NFPA labels which enable the fire department easy identification of the products health, flammability, and reactivity.  By following these rules and regulation we are involved in an extensive training program for our employees. This facility  has an ongoing safety training program for their personnel. This program involves all the regulated training programs plus any on the job situations that our employees might encounter.
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