Rhodia, Houston Plant - Executive Summary

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General Executive Summary for Risk Management Plan at the Rhodia, Houston facility. 
Date of plan: 6/18/99 
 
1.    Accidental Release Prevention and Emergency Response Policies 
We at Houston Plant are strongly committed to employee, public and environmental safety.  This commitment is demonstrated by our comprehensive accidental release prevention program that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at our facility.  It is our policy to implement appropriate controls to prevent possible releases of regulated substances. 
 
 
2.    The Stationary Source and the Regulated Substances Handled 
Our facility's primary activities encompass Chemical Manufacturer.  We have 5 regulated substances present at our facility.  These substances include Oleum (Fuming Sulfuric acid)  [Sulfuric acid, mixture with sulfur trioxide], Sulfur dioxide (anhydrous), Carbon disulfide, Vinyl acetate monomer  [Acetic acid ethenyl ester] a 
nd Sulfur trioxide.  Oleum (Fuming Sulfuric acid)  [Sulfuric acid, mixture with sulfur trioxide] is used for is used as a chemical intermediate, as a drying agent and is a raw material for dyes and detergents.  Sulfur dioxide (anhydrous) is used as a chemical intermediate, refrigerant, bleaching and food processing..  Carbon and Vinyl acetate monomer  [Acetic acid ethenyl ester] is received as a waste stream for energy recovery and raw material value..  Sulfur trioxide is used as an intermediate in the production of high purity acid used in the electronic industry. 
 
The maximum inventory of Oleum (Fuming Sulfuric acid)  [Sulfuric acid, mixture with sulfur trioxide] at our facility is 34,000,000 lb., while Sulfur dioxide (anhydrous), Carbon disulfide, Vinyl acetate monomer  [Acetic acid ethenyl ester] and Sulfur trioxide are present at our facility in quantities of 2,800,000 lb., 36,000 lb., 24,000 lb. and 13,000 lb. respectively. 
 
3.    The Worst Case Release Scenario(s) and the Alternati 
ve Release Scenario(s), including administrative controls and mitigation measures to limit the distances for each reported scenario 
To perform the required offsite consequence analysis for our facility, we have used the EPA's OCA Guidance Reference Tables or Equations and the EPA's RMP Guidance for Waste Water Treatment Plants Reference Tables or Equations.  The following paragraphs provide details of the chosen scenarios. 
 
The worst case release scenario submitted for Program 2 and 3 toxic substances as a class involves a catastrophic release from Sulfur Dioxide.  In this scenario 300,000 lb. of Sulfur Dioxide (anhydrous) is released.  The toxic liquid released is assumed to form a 1 cm deep pool from which evaporation takes place.  The entire pool is estimated to evaporate over 10 minutes.  The released quantity has been limited to 80% of the maximum capacity of the source by a system of administrative controls.  At Class F atmospheric stability and 1.5 m/s windspeed, the maximum dis 
tance of 19 miles is obtained corresponding to a toxic endpoint of 0.0078 mg/L. 
 
The alternative release scenario for Sulfur Dioxide (anhydrous) involves a release of Sulfur Dioxide.  The scenario involves the release of 1,500 lb. liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes place.  The entire pool is estimated to have evaporated after 1 minutes.  The release is also assumed to be controlled by excess flow valve(s) and emergency shutdown system(s).  These active mitigation systems have the effect of reducing the length of time the release would occur. Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.0078 mg/L of Sulfur Dioxide (anhydrous) is 0.6 miles. 
 
The alternative release scenario for Carbon disulfide involves a release from TS Carbon Disulfide.  The scenario involves the release of 1,600 lb. of liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes place.  The entire pool is 
estimated to have evaporated after 15 minutes.  Passive mitigation controls such as dike(s) are taken into account to calculate the scenario, having the effect of reducing the surface area of the liquid pool.  Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.16 mg/L of Carbon Disulfide is 0.27 miles. 
 
The alternative release scenario for Sulfur Trioxide involves a release from TXUP, of Sulfur Trioxide.  The scenario involves the release of 5000 lb. of liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes place.  The entire pool is estimated to have evaporated after 570 minutes.  Passive mitigation controls such as enclosure(s) are taken into account to calculate the scenario, having the effect of reducing the surface area of the liquid pool and enclosing the gas release inside a building. Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.010 mg/L of Sulfur trioxide is 0.26 miles. 
 
The alt 
ernative release scenario for Oleum (Fuming Sulfuric acid)  [Sulfuric acid, mixture with sulfur trioxide] involves a release from Regen 2 Unit.  The scenario involves the release of 2175 lb. of liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes place.  The entire pool is estimated to have evaporated after 10 minutes.  The release is also assumed to be controlled by emergency shutdown system(s).  These active mitigation systems have the effect of reducing the length of time the release would occur.  Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.01000 mg/L of Oleum (Fuming Sulfuric acid)  [Sulfuric acid, mixture with sulfur trioxide] is 0.19 miles. 
 
The alternative release scenario for Vinyl acetate monomer  [Acetic acid ethenyl ester] involves a release from TS Vinyl Acetate.  The scenario involves the release of 2900 lbs. of liquid is assumed to be released to form a 1 cm deep pool from which evaporation takes plac 
e.  The entire pool is estimated to have evaporated after 31  minutes.  Passive mitigation controls such as dike(s) are taken into account to calculate the scenario, having the effect of reducing the surface area of the liquid pool.  Under neutral weather conditions, the maximum distance to the toxic endpoint of 0.26 mg/L of Vinyl acetate monomer  [Acetic acid ethenyl ester] is 0.16 miles. 
 
4.    The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps 
Our facility has taken all the necessary steps to comply with the accidental release prevention requirements set out under 40 CFR part 68 of the EPA.    The following sections briefly describe the elements of the release prevention program that is in place at our stationary source. 
 
Process Safety Information 
Houston Plant maintains a detailed record of safety information that describes the chemical hazards, operating parameters and equipment designs associated with all processes. 
 
Process Hazard Analysis 
(PHA) 
Our facility conducts comprehensive studies to ensure that hazards associated with our processes are identified and controlled efficiently.  The methodology used to carry out these analyses is Checklist, What If/Checklist (combined), HAZOP (Hazard and Operability) and Fault Tree.  The studies are undertaken by a team of qualified personnel with expertise in engineering and process operations and are revalidated at a regular interval of five years.  Any findings related to the hazard analysis are addressed in a timely manner.  The most recent PHA/update was performed on 05/13/1999. 
 
Operating Procedures 
For the purposes of safely conducting activities within our covered processes, the Houston Plant maintains written operating procedures.  These procedures address various modes of operation such as initial startup, normal operations, temporary operations, emergency shutdown, emergency operations, normal shutdown and startup after a turnaround.  The information is regularly reviewe 
d and is readily accessible to operators involved in the processes. 
 
Training 
The Houston Plant has a comprehensive training program in place to ensure that employees who are operating processes are competent in the operating procedures associated with these processes.  Refresher training is provided at least every three years and more frequently as needed. 
 
Mechanical Integrity 
Houston Plant carries out maintenance checks on process equipment to ensure proper operations.  Process equipment examined by these checks includes among others; pressure vessels, storage tanks, piping systems, relief and vent systems, emergency shutdown systems, controls and pumps.  Maintenance operations are carried out by qualified personnel with previous training in maintenance practices.  Furthermore, these personnel are offered specialized training as needed.  Any equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner. 
 
Management of Change 
Written procedures 
are in place at Houston Plant to manage changes in process chemicals, technology, equipment and procedures.  The most recent review/revision of maintenance procedures was performed on 02/14/1998.  Process operators, maintenance personnel or any other employee whose job tasks are affected by a modification in process conditions are promptly made aware of and offered training to deal with the modification. 
 
Pre-startup Reviews 
Pre-start up safety reviews related to new processes and to modifications in established processes are conducted as a regular practice at the Houston Plant.  The most recent review was performed on 06/02/1999.  These reviews are conducted to confirm that construction, equipment, operating and maintenance procedures are suitable for safe startup prior to placing equipment into operation. 
 
Compliance Audits 
The Houston Plant conducts audits on a regular basis to determine whether the provisions set out under the RMP rule are being implemented.  The most recent compl 
iance audit was conducted on 07/02/1998.  These audits are carried out at least every 3 years and any corrective actions required as a result of the audits are undertaken in a safe and prompt manner. 
 
Incident Investigation 
The Houston Plant promptly investigates any incident that has resulted in, or could reasonably result in a catastrophic release of a regulated substance.  These investigations are undertaken to identify the situation leading to the incident as well as any corrective actions to prevent the release from reoccurring.  All reports are retained for a minimum of 5 years. 
 
Employee Participation 
The Houston Plant truly believes that process safety management and accident prevention is a team effort.  Company employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements.  In addition, our employees have access to all information created as part of the facility's implementation of the RMP rule, including informat 
ion resulting from process hazard analyses in particular. 
 
Contractors 
On occasion, our company hires contractors to conduct specialized maintenance and construction activities.  Prior to selecting a contractor, a thorough evaluation of safety performance of the contractor is carried out.  Houston Plant has a strict policy of informing the contractors of known potential hazards related the contractor's work and the processes.  Contractors are also informed of all the procedures for emergency response should an accidental release of a regulated substance occur. 
 
 
5.    Five-year Accident History 
Houston Plant has had an excellent record of preventing accidental releases over the last 5 years.  Due to our stringent release prevention policies, no accidental release has occurred during this period. 
 
 
 
6.    Emergency Response Plan 
Houston Plant maintains a written emergency response plan to deal with accidental releases of hazardous materials.  The plan includes all aspects of emergency respons 
e including adequate first aid and medical treatment, evacuations, notification of local emergency response agencies and the public, as well as post-incident decontamination of affected areas. 
 
To ensure proper functioning, our emergency response equipment is regularly inspected and serviced.  In addition, the plan is promptly updated to reflect any pertinent changes taking place within our processes that would require a modified emergency response. 
 
7.  Planned Changes to Improve Safety 
In order to encourage continuous improvement in all elements of Process Safety the facility  regularly reports progress of improvement efforts that are described in the Process Safety Management Plan.  Many of these improvements are results of audits and other reviews such as Management of Change, Process Hazard Analysis, Accident Investigations and others.
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