Minnesota Corn Processors - Marshall Facility - Executive Summary

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Executive Summary 
 
 
1.0 Introduction 
 
This Risk Management Plan (RMPlan) was prepared to meet the requirements of the U.S. Environmental Protection Agency (EPA) Risk Management Program (RMP) Rule (40 Code of Federal Regulation (CFR) 68).  Minnesota Corn Processors (MCP) is a covered facility under the rule because processes contain more than a threshold quantity of a regulated substance.  The MCP process meets Program Level 3 criteria.  The actual components of the required RMP include: 
 
( Conduct a hazard assessment (release scenarios) 
( Develop and implement a accident prevention program 
( Develop and implement an emergency response program 
( Development and implementation of a management system organizational structure 
( Submittal of a RMP Plan 
 
The purpose of the RMP is to prevent the accidental release and to minimize the consequences of any such release of hazardous substances. 
 
At MCP, we are committed to operating and maintaining our processes (especially those using hazardous  
substances) in a safe and responsible manner.  We use a combination of accidental release prevention programs and emergency response planning programs to help ensure the safety of our employees and the public as well as protection of the environment.  This document provides a brief overview of the comprehensive risk management activities that we have designed and implemented, including: 
 
( A description of our facility and use of substances regulated by EPA's RMP regulation 
( A summary of results from our assessment of the potential off-site consequences from accidental chemical releases 
( A five-year accident history for accidental releases of chemicals regulated by EPA's RMP rule 
( An overview of our accident prevention program 
( An overview of our emergency response program 
( An overview of planned improvements at the facility to help prevent accidental chemical releases from occurring and adversely affecting our employees, the public, and the environment 
( The certifications that E 
PA's RMP rule requires us to provide 
( The detailed information (called data elements) about our risk management program 
2.0 Stationary Source and Regulated Substances 
 
MCP operates a wet corn milling facility in Marshall, Minnesota.  Operations at the site include raw material receiving and storage, corn processing and co-product separation, product storage and shipping.  The primary products are corn sweeteners, cornstarch, and ethanol.  In our processes, we use two toxic chemicals stored in quantities greater than the EPA RMP Threshold Quantity limit.  The two chemicals and quantities are identified below. 
 
Toxics    Quantity    Thresholds 
 
1.    Sulfur Dioxide    10,200 gal. AST (103,700 lbs. @ 85% Admin. Control)    5,000 lbs. 
2.    Chlorine    16,000 lbs. (8-2,000 lb. Cylinders)    2,500 lbs. 
 
MCP does not use flammable substances in quantities exceeding EPA RMP Threshold Quantity limits. 
 
Sulfur dioxide is used in the steeping process.  Liquid sulfur dioxide is vaporized and introduced into the process 
water line.  The vaporized sulfur dioxide is dissolved into the process water and produces a sulfurous acid solution.  The sulfurous acid solution minimizes bacterial growth and prepares corn for further processing.  The process water is recovered and added back into the process in a continuous loop.  Chlorine is used at the cooling towers and water reclaim tank.  Chlorine is drawn into the water stream from storage cylinders to keep a bacteria-free system. 
 
Our accidental release prevention programs and our contingency planning efforts help us effectively manage the potential hazards related to our use of these chemicals.  Administrative controls, mitigation systems, and preventive measures used at MCP include: 
 
( Chemical permit system for sulfur dioxide storage to limit the quantity in the tank to 85 percent capacity 
( High level tank alarm for filling operations 
( Release sensors and alarms 
( Excess flow valve/regulator (system shutdown) 
( On-site emergency response team (HAZMAT) 
 
( Monitoring of unloading operations 
( A preventative maintenance program to ensure equipment integrity and proper operation 
( Standard operating procedures 
( Chlorine tanks designed and operated according to Chlorine Institute Standards. 
( Pressurized vacuum flow system (system shutdown) 
( Chlorine container response kit 
( Water fog/stream for vapor cloud 
( Pressure Relief Valves and Rupture Disks 
 
3.0 Key Off-Site Consequence Analysis Scenarios 
 
EPA's RMP rule requires that we conduct a hazard assessment and provide information about the worst-case release scenario(s) and alternative release scenario(s) for our facility.  This information identifies the potential hazards and the potential risks they pose.  The following are brief summaries of these scenarios, including information about the key administrative controls and mitigation measures to limit exposure distances for each scenario. 
 
Worst-Case Release Scenario 
 
The worst-case scenario (WCS) is an evaluation of the impact of a r 
elease of a hazardous substance from a complete failure (catastrophe) of the largest vessel, releasing the entire contents over a ten-minute period under the most stable weather conditions.  The probability of a release meeting these conditions is extremely small. 
 
The worst-case toxic release scenario at MCP's Marshall Facility is the rupture of the sulfur dioxide outdoor aboveground storage tank and release of the entire contents (85% tank capacity = 103,700 lbs.).  The worst release would occur over a 10-minute period and the distance to the toxic endpoint (3 ppm) is 25 miles.  The exposure distance was obtained using EPA Risk Management Program Guidance (EPA 550-B-98-010).  There are no mitigation measures included in this scenario.  Public and environmental receptors in this WCS include:  residences, schools, hospitals, public recreational areas, commercial / industrial areas, national or state parks / forests and officially designated wildlife refuges.  The population was estimat 
ed and public receptors were identified using Landview III mapping software and U.S. Census Data.  Environmental receptors were identified using U.S. Geological Survey Quad Maps.  Additional information regarding the WCS is included in the RMP Registration Data Elements. 
 
Alternate Release Scenarios 
 
An Alternate Release Scenario (ARS) is the evaluation of the impact of a release of smaller quantities of material.  The causes and the amount in these scenarios were determined based on site-specific data.  The probability of this scenario is higher than worst-case scenarios and therefore is the primary focus for on- and off-site emergency planning.  Nonetheless, this scenario remains a low probability event. 
 
Alternate toxic release scenarios have been prepared and selected for sulfur dioxide and chlorine.  The selected sulfur dioxide scenario involves a release when a valve on the sulfur dioxide transfer line is inadvertently opened due to human error.  Sulfur dioxide is released at a r 
ate of 45 lbs. per minute for 20 minutes (900 lb. release).  The distance to the toxic endpoint (3 ppm) is 0.3 miles.  The exposure distance was obtained using EPA Risk Management Program Guidance (EPA 550-B-98-010).  Detection equipment, alarm system, excess flow valves, and an on-site HAZMAT response team help limit release duration.  Public receptors include commercial/industrial areas.  There are no environmental receptors within the sulfur dioxide ARS exposure distance. 
 
The selected ARS for chlorine is described below.  Chlorine could be released at the facility if a one-ton chlorine cylinder valve is sheared off.  The entire contents of the cylinder (2,000 lbs.) could be released at a rate of 346 lbs/min.  The release would occur inside the chlorine building (passive mitigation).  Liquid chlorine is released which flashes immediately to vapor.  The distance to the toxic endpoint (3 ppm) is 0.6 miles.  Active mitigation in this scenario includes release sensors and alarms, vacuum 
system shutdown, the presence of unloading personnel, and on-site HAZMAT personnel and equipment.  The exposure distance was obtained using EPA Risk Management Program Guidance (EPA 550-B-98-010).  Public receptors include commercial / industrial areas.  There are no environmental receptors within the exposure distance. 
 
We are using this information to help us to ensure that our emergency response plan and the community emergency response plan address all reasonable contingency scenarios. 
 
4.0 General Accidental Release Prevention Program 
 
MCP takes a systematic, proactive approach to evaluating chemical processes.  Using this approach, the design, technology, operation and maintenance activities, emergency preparedness plans, training, process changes, and other elements that affect processes are all considered.  Through evaluation, the consequences of catastrophic releases can be prevented or minimized. 
 
MCP processes are currently in compliance with OSHA Process Safety Management  
(PSM) Standard (29 CFR 1910.119).  The PSM Program addresses chemical accident prevention in a way that protects employees as well as the public, and the environment.  The purpose of the PSM Program is to prevent unwanted releases or minimize the impacts of accidental releases of hazardous chemicals, especially into locations that could expose employees and others to serious hazards.  Our management systems address each of the key features of successful prevention programs including: 
 
( Process safety information: Technical information about how a process operates 
( Process hazard analysis: Technical analysis of the plants processes in order to anticipate what might go wrong 
( Operating procedures: Technical and administrative procedures used to operate the plant safely 
( Training: Provide employees with information necessary to ensure safe operation 
( Mechanical integrity: Proper care on an ongoing basis 
( Management of change: Analyze and understand the impact of changes in equipment 
, procedures or personnel 
( Pre-startup review: Check equipment and make sure everyone knows what to do before starting a process 
( Compliance audits: Evaluate whether any safety hazards exist 
( Incident investigation: Procedures for investigating the cause of an accident and developing measures to prevent future accidents 
( Employee participation 
( Hot work permit 
( Contractors 
 
PSM modifications necessary to further account for protection of public health and the environment will be made when PSM elements are updated under the existing schedule as required by OSHA.  The PSM Program was last revised on December 22, 1997.  The PSM Program is maintained by the Safety Manager. 
 
Our company and our employees are committed to the standard that the PSM Program and Risk Management Program set.  We do business, and we have specific accountabilities and controls to ensure that we are meeting high standards for accident prevention.  MCP has developed a risk management system which identifies po 
sitions and responsibilities for proper management of the RMP. 
 
5.0 Five-Year Accident History 
 
We keep records for accidental chemical releases and "near misses" that occur at our facility.  Incident reports are completed and the appropriate emergency response agencies are notified by MCP for any accidental chemical release exceeding federal or state Reportable Quantities.  Reporting and notification procedures are documented in the MCP Environmental Compliance Manual.  Reports are also completed for First Aid or chemical release "near misses" that occur on-site.  Appropriate corrective measures are taken to help prevent similar situations from occurring in the future.  The following is a brief summary of accidental chemical releases involving materials covered under EPA's RMP rule which occurred at MCP during the past five years: 
 
- Sulfur Dioxide, 12/19/95, 3:00 PM, 900 lbs., Released from pipeline valve (human error) 
 
For this incident, we conducted a formal incident investigation  
to identify and correct the root causes of the event.  Workers exposed during the sulfur dioxide release were transported to the hospital for observation and then released to return to work.  The incident did not result in any off-site consequences that affected the public or damaged the environment.  Additional information regarding this release is included in the RMP Registration Data Elements. 
 
6.0 Emergency Response Program 
 
MCP has developed and maintains an Emergency Response / Fire Prevention Plan and an Emergency Response Plan for Hazardous Chemical Spills, Leaks and Releases.  The Plans consolidate various federal, state, and local regulatory requirements for emergency response planning.  Our emergency response program provides the essential planning and training for effectively protecting workers, the public, and the environment during emergency situations.  The Emergency Response Plans include written procedures to follow in the event of an incident.  Furthermore, we coordin 
ate our plan with the Marshall Emergency Planning Committee (LEPC) and perform drills regularly.  In addition, several MCP employees serve as members on the LEPC. 
 
7.0 Planned Changes to Improve Safety 
 
The following is a list of improvements that we are planning to implement at the facility to help prevent and/or better respond to accidental chemical releases: 
 
- Evaluate the use of alternate sources of sulfur dioxide (dry/solid forms) 
- Evaluate placing administrative controls on the quantity of sulfur dioxide stored on-site. 
- Evaluate the use of chemical release scrubbers. 
 
In addition, recommended changes identified during Process Hazard Analysis will be implemented as necessary.
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