NOVA Chemicals Inc., Beaver Valley Site - Executive Summary

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RMP Executive Summary 
 
NOVA Chemicals Beaver Valley site occupies about 300 acres in Potter Township, Pennsylvania, approximately 30 miles northwest of Pittsburgh. The Ohio River borders the site on the north. The area south of the site is wooded hillsides. The nearest residence is approximately one half mile away. There are no schools or hospitals within three miles of the site.  
 
Currently, there are 548 NOVA and contract employees working at the site, in manufacturing, technology and administrative jobs.    
 
The Beaver Valley site is a national leader in the production of plastic resin for polystyrene foams and heat resistant engineering resins. The major products are Dylite expandable polystyrene, Dylene polystyrene and Dylark engineering resins. 
 
NOVA Chemicals is a member of the Chemical Manufacturers Association and is a Responsible Care Company 
 
The Beaver Valley site approach to chemical safety is best described by the NOVA Chemicals Safety, Health, Environment and Risk Policy 
which states that:  
 
NOVA Chemicals is committed to making protection of human health, safety and the environment it first priority. Protection and enhancement of the environment and the health and safety of employees, customers and the public form an integral pert of all of our business processes including: planning; research; facility acquisition, development and operation; product development; marketing; logistics; waste management; and decommissioning and divestiture of facilities.  NOVA Chemicals readily accepts this life cycle stewardship responsibility for all of its operations and will be a pace setting company in its demonstrated performance. 
 
We operate on the premise that all accidents and incidents are preventable. 
 
We fulfill this policy commitment through the application of a comprehensive safety, health, environment and risk (SHER) management system that assures that: 
 
   Identifiable safety, health and environmental risks associated with NOVA Chemical's businesses, opera 
tions and products are assessed and successfully managed; 
 
   Effective loss prevention programs are in place and physical assets are protected; 
 
   Safety, health and environmental laws, regulations, and permit requirements are adhered to; 
 
   Appropriate policies, programs and procedures are in place and continuous employee learning opportunities are available; 
 
   Best available science, technology and industry practices are being applied with due consideration given to economics and technical practicality; 
 
   Organizational responsibilities are clearly defined, understood and carried out and every employee is responsible and accountable for NOVA Chemicals' performance; 
 
   Systems are in place to ensure that our SHER policies, standards ad procedures are being followed and that performance is measured against the best in the industry; 
 
   Change, whether it be in leadership, organization, chemical or business processes, is managed in a way that maintains, or if possible, enhances SHER performan 
ce; 
 
   We only engage in business with companies which demonstrate a commitment to responsible SHER practices, and NOVA Chemicals' SHER performance is communicated to all stakeholders. 
 
Excellence in SHER performance is everyone's responsibility.  All employees must adopt and encourage safe work practices and conduct all work-related activities in an environmentally responsible manner.  Leadership in all facilities and business units are accountable for their organization's SHER performance, and for achieving satisfactory performance from their customers, suppliers, carriers and contractors.  
 
 
 
 
NOVA Chemicals Beaver Valley Site Process Description and Regulated Substances Handled  
 
NOVA Chemicals Beaver Valley Site is required to comply with the EPA 40 CFR 68, Risk Management Program (RMP) because n-pentane and iso-pentane are  listed chemicals in the RMP and are used in our manufacturing processes in amounts above the threshold quantity (TQ). Both n-pentane and iso-pentane are us 
ed to produce different grades of expandable polystyrene resin (EPS) which is the main product manufactured at the Beaver Valley Site. 
 
N-pentane and iso-pentane are used in both the D2 and D3 / D4 process areas to produce EPS.  The D2 process area is on the East Side of the site and the D3/D4 process area is on the West End of the site. Both n-pentane and iso-pentane are delivered to the site in 30,000 gallon capacity rail tankcars. 
 
In the D2 area, n-pentane and iso-pentane are stored in maximum amounts of 8,500 gallons each ( 44,600 pounds.)  in 2 -10,000 gallon capacity storage tanks.  These two tanks supply the two types of pentane used in the D-2 process area. 
 
In the D3/D4 area, n -pentane is stored at a maximum amount of 130,000 gallons (682,500 pounds) in a 250,000 gallon capacity storage sphere. In another tank farm area adjacent to the D3/D4 process area, iso-pentane is stored at a maximum amount of 11,200 gallons (58,800 pounds). In the same tank farm area, cyclo-pentane i 
s stored in a 20,000-gallon capacity storage tank at a maximum amount of 16,000 gallons (84,000 pounds). A third tank, also in the same storage area, contains a mixture of iso-pentane and cyclo-pentane in a 20,000-gallon capacity tank at a maximum amount of 16,000 gallons (84,000 pounds).  
 
Worst-case release scenarios 
 
EPA has defined a worst case release as the release of the largest quantity of a regulated substance from a vessel or process line that results in the greatest distance from the point of release to a specificed end point. At the Beaver Valley site, the only regulated substances that are used are n-pentane and iso-pentane. Both are flammable substances. 
 
A vapor cloud explosion is specified by the EPA as the worst case scenario for flammable substances. An estimate of the distances to an overpressure endpoint of 1 pound per square inch (psi) resulting from a vapor cloud explosion of a cloud containing the largest quantity of the regulated flammable substance from a vesse 
l or process is required. 
 
Applying the worst-case scenario definitions at Beaver Valley, it was determined that two worst case situations must be considered because each worst case scenario has a slightly different set of public receptors. 
 
Worst -Case Number 1: 
 
Worst-case scenario number 1 involves a release of 525,000 pounds (100,000 gallons) of n-pentane from the pentane storage sphere in the D3/D4 process area to a diked area and 157,500 pounds (30,000 gallons) of pentane from a rail tank car connected to this sphere. 
 
Applying the May 17, 1999 amendments to Section 112(r) regarding the worst case release scenario for regulated flammable substances, the amount of pentane vaporized during this release was calculated to be 80,343 pounds/10 minutes.  The release of this amount of n-pentane, coupled with a vapor cloud explosion would result in a 1 pound per square inch (psi) overpressure at an endpoint of 0.34 miles.  RMP Comp was the modeling software used to determine this overpres 
sure endpoint.    
 
Worst - Case Number 2:  
 
Worst-case scenario number 2 involves the release of the maximum quantity of n-pentane contained in the D2 area pentane storage tank, 44,625 pounds (8,500 gallons), plus the minimum quantity contained in the D2 area iso-pentane storage tank, 5,200 pounds (1,000 gallons) just prior to refilling. Both of these tanks are located in a diked area.  Also included in this release scenario is the quantity contained in a full iso-pentane rail tank car, 157,500 pounds (30,000 gallons) that would be connected to the iso-pentane storage tank to refill it.  
 
Applying the May 17, 1999 amendments to Section 112(r) regarding the worst case release scenario for regulated flammable substances, the amount of pentane vaporized during this release was calculated to be 62,075 pounds/10 minutes.  The release of this amount of pentane/iso pentane, coupled with a vapor cloud explosion, would result in a 1 pound per square inch (psi) overpressure at an endpoint of 0. 
32 miles.  RMP Comp was the modeling software used to determine this overpressure endpoint. 
 
Alternative Release Case Scenario 
 
A team of employees from the Beaver Valley Site met on October 8, 1998 to review the Risk Management Program, worst -case release scenarios and to develop an alternate - release scenario. The members of this team were knowledgeable in the D2 and D3/D4 processes and were familiar with the manner in which pentane and iso-pentane are handled at the site.  
 
The assessment team came to the consensus that the alternative release case that would have a greater likelihood of occurring than the worst case scenario and that would reach an off-site end point would involve the release of n-pentane or iso-pentane from a transfer line during the railcar unloading process. It was envisioned that pentane would be released due to a sudden uncoupling of the transfer hose or a failure of the transfer pipe flanges, joints or welds. The pentane would ignite, causing a pool fire. T 
he initial operational flow rate through the transfer hose or piping is 1575 pounds./minute.   The total cross sectional area of the pipe failure is estimated to be 3.03 square inches. The pipe operating pressure is estimated to be 30 psi. Active mitigation would be done to reduce the release rate by a factor of 0.5.  
 
Using the conditions in the RMP Comp, model the estimated distance to the heat radiation end point is 0.21 miles.  
 
Accidental Release Prevention Programs 
 
To prevent the situations described above from occurring, these processes are covered under OSHA Process Safety Management (PSM) rule, OSHA 1910.119. All 14 elements required under the PSM rule are in place at the site and have been integrated into the prevention plan requirements under the Risk Management Program. Compliance with the PSM rule provides the foundation for compliance with the Risk Management Program, and there is an on-going effort to maintain and improve our compliance programs related to PSM. 
 
Some of 
the specific prevention measures in place include the following: There are pressure relief systems on the storage tanks. Dikes surround the storage tanks. There are on-going equipment inspection programs in place to monitor mechanical integrity. The tanks are protected by firewater deluge systems. Area classifications are required to guard against the introduction of ignition sources into the processes. There are hydrocarbon sensors and alarms in the area to detect pentane releases.  Pentane unloading operations are continuously monitored by the site's liquid handling technicians.   
 
It should be noted that all of our storage vessels are included in our Mechanical Integrity Inspection Program.  Procedures are in place to conduct inspections periodically by qualified personnel to reduce the risk of vessel failure. 
 
There have been no accidents at the Beaver Valley site involving pentane or iso-pentane in the last 5 years. In fact, pentane has been used at the site for more than 45 year 
s without any off-site incidents. 
 
To further improve site safety and emergency preparedness, the Beaver Valley Site coordinates its emergency response plan with the Beaver County Local Emergency Response Committee (LEPC). The site conducts annual training emergency response drills in conjunction with the LEPC.  The site safety leader maintains close communication with the Beaver County LEPC coordinator on a regular basis and is a member of the LEPC.
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