Cargill, Inc. - Executive Summary |
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1.0 CARGILL CORN MILLING DIVISION ACCIDENTAL RELEASE AND EMERGENCY RESPONSE POLICIES Cargill Inc. owns and operates a wet corn milling facility in Cedar Rapids, Iowa which is subject to U.S. EPA regulations governing Accidental Release Prevention Requirements: Risk Management Programs (RMP) under Section 112(r) of the Clean Air Act (40 CFR Part 68). This Risk Management Plan has been developed in accordance with the requirements specified under 40 CFR Part 68, Subpart G. The Risk Management Plan certifies that Cargill Corn Milling Division has instituted a Risk Management Program at the Cedar Rapids, Iowa facility that is in compliance with U.S. EPA RMP requirements. The Risk Management Plan follows the format provided by the RMP Data Elements published by U.S. EPA. In addition to identifying the applicable corporate policies and risk management systems, including comprehensive accident prevention and emergency response programs, the Risk Management Plan identifies a set of wor st case and alternative release scenarios and the facility's five-year accidental release history. The Risk Management Plan also verifies that prevention, mitigation, and emergency response plans are appropriately designed to minimize risks to workers and the potentially affected public. RMP Data Elements are included as part of this Risk Management Plan. 1.1 Corporate Statement Cargill's policy is to conduct all business activities in a manner that protects the environment and the health and safety of our employees, contractors, customers and the public. Environment. Cargill will comply with all applicable laws and regulations; promote waste reduction, resource and property conservation and environmental protection; and train employees to be knowledgeable about all environmental matters relevant to their work. Health and Safety. Cargill will design, construct, maintain and operate facilities to protect human and physical resources; provide and require use of adequate protecti ve equipment and measures, and insist that all work, however urgent, be done safely. Food and Product Safety. Cargill will provide safe food, feed, and materials for people and animals by using production, storage and transportation facilities that ensure the safety of products; choose suppliers that meet our requirements for safe raw materials and ingredients; and provide employees the training and resources they need to meet their individual responsibilities. The Cargill Foods Corn Milling Division plant in Cedar Rapids is designed, maintained and operated so as to minimize adverse impacts to its employees, local communities and the environment. In order to insure the safe and effective response to an unlikely emergency in the workplace, the Cedar Rapids Corn Milling plant coordinates its safety and emergency response program with the local community's emergency response personnel. Plant management makes information available to the local community regarding the hazards and risk s in operating the facilities and the prevention techniques in place. This includes insuring that all regulatory reporting requirements are met. Plant management is fully informed as to the materials which are stored or used on-site and aware of the possible risk associated with their handling, storage, use, disposal or accidental release. Material Safety Data Sheets (MSDS) for all materials utilized at the plant are maintained on-site. The plant maintains inspection records and up-to-date procedures to insure the proper control of hazardous materials. Procedures and systems are devised which include provisions for the periodic testing, review, and update of the emergency response programs. Employees are trained and periodically retrained in the methods of detection of hazardous material releases, the potential physical and health risks associated with the materials, and methods for protecting themselves, co-workers, and the public. The plant investigates, corrects, and reports in writing all incidents involving hazardous materials having caused, or having the potential for causing, injury or loss. Adherence to this policy is essential in reducing the risk of accidental releases of hazardous materials and in decreasing the likelihood of adverse impacts to Cargill's employees, the local communities and the environment. 1.2 Risk Management System Cargill Corn Milling Division's Cedar Rapids plant has developed a management system to oversee the implementation of the Risk Management Program in accordance with the requirements of 40 CFR Part 68, Subpart G. The management system (shown in Figure 1-1) identifies job functions by responsibility level. Figure 1-1 Management Organization for Risk Management Plan Facility Manager Plant Superintendent EHS/Quality Department Superintendents Shift Supervisor Safety Director Environmental Coordinator Responsibilities of Plant S uperintendent: - Review and approve facility safety policies/programs Responsibilities of Environmental Coordinator - Oversee implementation of RMP - Track new Environmental Regulations Responsibilities of Facility Manager - Oversight of facility operation - Facility spokesperson Responsibilities of Department Superintendents: - Compliance with Process Safety Management Program - Completion of incident investigations - Follow-up to audit findings - Oversee and document maintenance - Complete management of change and pre-startup safety reviews - Department specific employee safety training - Compliance with facility safety policies/programs - Development of operating procedures Responsibilities of Shift Supervisor: - Incident Commander for emergency response - Planning and execution of emergency drills Responsibilities of Safety Director - Develop/review facility safety policies/programs - Development of facility PSM program/procedures - Oversee contractor safety pr ogram - Track new safety regulations - Oversee compliance audits - Oversee facility safety training programs - Oversee implementation of PSM - Oversee MOC's - Development of facility EAP - Review Incident Reports 2.0 PROCESSES AND SUBSTANCES SUBJECT TO 40 CFR PART 68 The Cargill Foods Corn Milling Division plant in Cedar Rapids produces corn syrup, cornstarch and other byproducts, such as gluten feed and meal, from the corn milling process. The raw materials and process chemicals utilized by the plant are delivered via truck and rail from external sources. Access to the site by vendors, employees, and visitors is controlled by fencing and security check points. Several of the chemicals utilized in the corn milling process at the Cedar Rapids facility are regulated under 40 CFR Part 68. The Process Mill/Steephouse, Modhouse, and Specialty Starch departments each store and maintain chemicals that are present at or above threshold amounts for regulated substances. These depart ments contain the only processes at the facility that are subject to the above regulation, which addresses the potential off-site hazards of accidental releases. The regulated substances include: sulfur dioxide (SO2), ethylene oxide (EO), and propylene oxide (PO). The EPA Risk Management Regulation identifies three levels of requirements for industrial processes. Program 1 can be applied to any process which has not had a "significant" release of a regulated substance over the five year period prior to the June 1999 compliance date and for which the worst-case release does not affect "public receptors" (e.g., residences, parks and recreation areas, commercial/industrial facility, hospitals). Program 2 applies to any process that is ineligible for Program 1 and is not subject to Program 3. Program 3 applies to all processes, such as those present at the Cargill Corn Milling Division facility, that are subject to the Occupational Safety and Health Administration (OSHA) Process Safet y Management Standard (PSM). The Cargill Accident Prevention Program elements are adopted directly from the compliance program for the PSM standard, consistent with the Level 3 RMP Program requirements for this Cargill facility under 40 CFR Part 68. Program 3 related information for the Process Mill/Steephouse, Modhouse, and Speciality Starch departments is included in the Data Elements section of the Risk Management Plan. 2.1 Process Mill/Steephouse Department The corn milling process at the Cargill Cedar Rapids facility is designed to extract useable starch and sugars from corn kernels in order to produce various end-products. The first step in the corn milling process involves steeping the corn kernels. During steeping the corn is covered with water into which liquid SO2 has been injected. The SO2 and water form a dilute solution of sulfurous acid that helps to soften the kernel, breakdown proteins and remove soluble constituents. The steeped corn then travels through degermina ting mills and separation processes designed to remove the germ and separate out the starch. In the final step, the starch slurry is rinsed in water into which additional liquid SO2 is injected. Approximately 80% of this starch slurry is utilized in the production of corn syrup and starch. The Process department is responsible for the storage and transfer of sulfur dioxide (SO2) that is utilized in the corn milling process. The SO2 is stored in an exterior storage tank as a pure liquefied gas at ambient temperatures. The nominal capacity of the tank is 28,000 gallons (341,600 lb). Administrative controls and interlocks limit the maximum amount stored at any time to 311,100 lbs. The storage tank is filled approximately every 25 days via 90-ton railcar. During rail disruption SO2 is received via truck. Access to the unloading area is limited by chain link fence and secured by locks. Only 1 railcar of SO2 is allowed on site at any time. 2.2 Modhouse Department Ethylene oxide i s stored in an exterior storage tank which is maintained at a temperature of no higher than 60oF. Pressure in the tank is maintained via a nitrogen blanket at 35 psig. EO is delivered approximately every 14 days via a dedicated railcar with a capacity of 24,500 gallons. Use of a dedicated railcar reduces the potential of contamination by another substance, which can cause polymerization and heating leading to over pressurization. Only one railcar at a time is allowed in the unloading area. The storage tank has a capacity of 25,650 gallons based on administrative controls. From the storage tank, EO is sent to the batch tank and then reactor vessels to be used in the production of ethylated starch. Access to the EO area is limited by chain link fence and secured by locks. 2.3 Specialty Starch Department The Specialty Starch Department is responsible for the storage and transfer of propylene oxide that is used in the production of propylated starch. The propylene oxide is stored in an underground storage tank that never contains more than 9,500 gallons. PO is delivered approximately every 10 days via a 6,500 gallon tank truck. The underground storage tank has a capacity of 9,500 gallons based on administrative controls. From the storage tank, PO is sent to the batch tank and then reactor vessels to be used to produce propylated starch. Access to the PO area is limited by chain link fences and secured by locks. The three processes and substances subject to regulation are summarized below: Process Department Substance Program Level Process Sulfur Dioxide 3 Modhouse Ethylene Oxide 3 Specialty Starch Propylene Oxide 3 3.0 HAZARD ASSESSMENT For the purposes of developing and maintaining adequate Risk Management Plans, the EPA has defined in its governing rules and guidance a series of modeling methods and assumptions which are to be used as adm inistrative guides for planning purposes. In order to standardize and simplify the many factors that can potentially occur in an accidental release situation, some of these assumptions may not take into account the available preventive measures or mitigation methods that could diminish or even eliminate the implied risks that are suggested by "worst-case" analyses. For that reason, both the results for the standardized "worst-cases" defined by the EPA methods and a set of alternative cases which are believed by Cargill to more realistically represent situations that may possibly, but rarely, occur within the lifetime of the facility are also presented. The sections of the Risk Management Plan which discuss both worst-case, and alternative cases, are meant to provide the data necessary to develop and evaluate possible improvements in the overall safety programs of the Cargill RMP program. 3.1 Worst-Case Release for Toxic Substances The worst-case release scenario, as defined by 40 C FR Part 68, is a sudden release of the maximum amount of a stored regulated substance from a single vessel, regardless of whether several vessels are interconnected. For toxic gases such as SO2 and EO stored at ambient temperatures, it is assumed that the release occurs over a 10-minute period. Toxic liquids, like PO, are assumed to spill instantaneously and spread to a depth of 1 cm in an undiked area or to cover a diked area. The duration of the release is based on the evaporation rate of the toxic liquid and the amount spilled. The regulated substance with the most extensive zone of influence, defined as the distance to specified toxic "endpoints", is considered the worst-case release for each facility. Only passive mitigation (e.g., dikes, enclosures) and administrative controls may be accounted for in the evaluation. EPA has established "toxic endpoints" for various chemicals based on the American Industrial Hygiene Association (ACGIH) Emergency Response Planning Guideline, Level 2 (ERPG-2), which protects individuals from health-threatening or escape-impairing injury. The ERPG-2 is defined as: "the maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to 1 hr without experiencing or developing irreversible or other serious health effects or symptoms which could impair an individual's ability to take protective action." Given that the worst-case is a 10-minute release duration with a 10-minute averaging time, the actual hazard zone is typically overestimated by the ERPG-2. Within such a time period there are a number of emergency measures that can reduce or eliminate exposures to levels this high for an interval much shorter than an hour. Based on a review of the quantity of regulated substance stored in vessels on-site, it was estimated that sulfur dioxide would result in the greatest distance to toxic endpoint. The toxic endpoint for SO2 is 0.0078 mg/L. Since the resulting planning zone pred icted for the "worst-case" SO2 toxic release potentially affects public receptors, regulated processes at the Cargill Corn Milling Division facility are subject to Program 3 requirements. 40 CFR Part 68 requires that the substance with the largest distance to toxic endpoint be reported in the Worst-Case Release section of the Risk Management Plan. Therefore, only the SO2 release results are included in the Data Elements section. The EPA's RMP Off-site Consequence Analysis Guidance (1999 Revised OCAG) lists a number of refined dispersion models that are available for off-site hazard assessment applications for risk management programs. Sulfur dioxide has a molecular weight that is substantially greater than the ambient air. Therefore, concentrated plumes of this substance resulting from accidental releases often display heavy-gas behavior. In such cases, near-field dispersion is dominated by gravitational slumping of the plume and entrainment of air at the plume-air interface. T he Dense Gas DISpersion (DEGADIS) Model (Version 2.1) was developed by the U.S. Coast Guard and the Gas Research Institute to model dense gas releases and its use has been approved by the U.S. EPA. The model is used to predict the dispersion of dense gases from ground level releases over flat, level terrain. For these reasons, DEGADIS was used to model the worst-case release scenarios. The 1999 Revised OCAG provides a basic approach to estimating endpoint distances based on an ambient air temperature of 77oF. However, the RMP rule requires that if dispersion techniques other than the OCAG are applied, the maximum daily temperature over the last three years be used. A review of National Climatic Data Center (NCDC) climatological data for the National Weather Service reporting station at Waterloo, IA, indicated a recorded high temperature over the last three years of 99oF. Under Section 68.22 (e), the RMP rule identifies "surface roughness" as a parameter to be specified in the h azard assessment. The surface roughness affects the amount of dispersion that occurs within a released plume and influences the distance to toxic endpoint. The surface roughness used in determining the distance to "toxic endpoint" should be characteristic of the transport path of the plume from the release point to the endpoint distance. 'Urban' surface roughness indicates areas where there are many obstacles, such as industrial buildings or trees. 'Rural' indicates that there are no buildings in the immediate vicinity of a facility and that the terrain is generally flat and unobstructed. In the immediate vicinity of the Cargill Corn Milling facility, the aerodynamic surface roughness is clearly 'urban' in nature. Then, depending on direction, the land use is both urban and rural. To the south-southeast of the plant, the land use is primarily rural. Otherwise, surrounding land use is urban. For this analysis, an 'urban' surface roughness value of 50 cm, which is consistent with the urban and mixed land use of the surrounding area, was utilized. In accordance with 40 CFR Part 68, the worst-case modeling is conducted assuming a very stable atmosphere with limited dispersion (F stability and 1.5 m/sec wind speed). Analysis of three years of meteorological data from the National Weather Service at Waterloo, IA indicates that these dispersion conditions occur approximately 6% of the time (or about 1.4 hours per day, on average). The most predominant directions of transport are to the northwest and southeast. 3.1.1 Worst-Case Release: Sulfur Dioxide The 40 CFR, Part 68 prescribed worst-case scenario for the Cedar Rapids facility consists of a 10-minute gaseous ground-level release of 311,100 lbs of stored sulfur dioxide, dispersed under atmospheric conditions of F stability and 1.5 m/sec wind speed. The modeling results indicated that the worst-case SO2 release would result in a distance to "toxic endpoint" of 10. miles. The worst-case impact zone encompasse s a resident population of approximately 150,000, based on the 1990 Federal Census, and estimated by applying EPA's Landview III program. Public receptors were identified using 1:24,000 scale U.S.G.S maps, supplemented with comprehensive maps of the local Cedar Rapids area (Rand McNally, 1990, and DeLorme Street Atlas USA, Version 5). The potential worst-case hazard zone includes schools, hospitals, prisons, public recreation areas, and industrial/commercial areas. Several environmental receptors (defined as National or State parks, forests, officially designated wildlife sanctuaries, preserves, refuges, and federal wilderness areas) are also located within the worst-case impact zone. The closest environmental receptor is the Palisades Kepler State Park. Cargill notes that it is impossible to release 311,100 lbs of SO2 in 10 minutes because the amount of heat energy required to so rapidly vaporize the liquid SO2 would not be available. If the storage tank were to breach, liquid SO2 would spill to the ground in a boiling pool. If a hole were to form in the vapor space of the storage tank, the flashing vapor in the tank would cause the tank to auto-refrigerate, thereby gradually reducing the release rate with time. However, Cargill evaluated this 10-minute release to comply with the noted regulation. 3.2 Alternative Releases of Toxic Substances Alternative releases are intended to represent release scenarios that have a greater likelihood of occurrence than a worst-case release. Alternative releases do not necessarily represent the types of releases that the PSM hazards analysis and/or accident history indicate would be most frequent, but rather a release that is somewhat more likely than the worst-case release and that generally still has the potential to affect off-site receptors. In accordance with the EPA's OCAG, a single alternative release scenario is reported for each regulated substance. Cargill performed a thorough review of the Process Mill/St eephouse, Modhouse, and Specialty Starch departments, utilizing engineering plans, operational experience, and maintenance records, in order to determine alternative release scenarios that could potentially result in off-site impacts. Each scenario was evaluated and the scenarios most likely to occur and to result in off-site impacts were selected for modeling. In order to determine the most conservative off-site consequence estimates, Cargill has chosen to include in the Risk Management Plan the alternative release scenarios that resulted in the greatest "toxic endpoint" distance for each regulated substance. In accordance with the RMP rule, alternative releases are modeled under typical (rather than worst-case) dispersion conditions. The EPA OCAG default dispersion conditions are neutral atmosphere, with dispersion neither enhanced nor limited (D stability and 3 m/sec wind speed). A review of climatological data for Waterloo, IA, confirmed that conditions of D stability and wind sp eeds of 3m/sec and greater are typical of the area and therefore are suitable for the evaluation of alternative releases. Unlike the worst-case release (for which an instantaneous spill or 10-minute ground-level gas release is assumed), alternative scenarios can account for the actual release configuration, and account for both active and passive mitigation. Alternative dispersion modeling was conducted using EPA's RMP Off-site Consequence Analysis Guidance (1999 Revised OCAG), and RMP Guidance for Chemical Distributors. 3.2.1 Sulfur Dioxide The alternative SO2 release scenario that would result in the greatest off-site impact involves a break in the SO2 unloading assembly at the delivery railcar. A break of this type would result in a hole in the unloading assembly of approximately 1.0 inches in diameter. The pressurized release of SO2 through hole of this size would result in two-phase flow (vapor and liquid) as the pressurized SO2 flashed to the vapor state. The modeling sho wed that SO2 would be released at a rate of 1,600 lbs/min. It is conservatively assumed that the sulfur dioxide would then be dispersed as a heavy gas and the excess flow valve would not engage. Cargill has estimated that it would take an operator approximately 30 minutes to respond and shutdown the flow of SO2, resulting in a total release of 48,000 lbs. This alternative SO2 release scenario is expected to be more representative of the maximum anticipated release at the facility than the "worst-case". The modeling indicates that under urban conditions, the distance to "toxic endpoint" would be 0.6 miles. The hazard impact zone encompasses an estimated residential population of approximately 1,800 persons, based on the 1990 Federal Census, and estimated in conjunction with EPA's Landview III database program. Public receptors in the alternative impact zone include a school, public recreation areas, and industrial/commercial areas. No environmental receptors would be affected. 3.2.2 Ethylene Oxide The alternative ethylene oxide release scenario that would result in the greatest off-site impact involves a break in the flexible ethylene oxide unloading line at the delivery railcar. It is estimated that a break in the unloading line would result in a hole of approximately 0.75 inches in diameter. The release rate for this scenario was conservatively estimated to be 660 lbs/min, using the EPA's OCAG. Although a release of this type could potentially occur, the frequency at which the hoses are replaced reduces the likelihood of a release to a very low level. Cargill has estimated that it would take an operator approximately 30 minutes to respond and shutdown the flow of ethylene oxide, resulting in a total release of 19,800 lbs. The modeling indicates that under 'urban' conditions, the distance to "toxic endpoint" would be 0.8 miles. The "toxic endpoint" for ethylene oxide is 0.09 mg/L. The hazard impact zone encompasses an estimated residential populatio n of approximately 3,800 persons, based on the 1990 Federal Census, and estimated in conjunction with EPA's Landview III database program. Public receptors in the alternative impact zone include schools, public recreation areas, a hospital, and industrial/commercial areas. No environmental receptors would be affected. 3.2.3 Propylene Oxide The alternative propylene oxide release scenario that would result in the greatest off-site impact involves a break along the pipe bridge from the storage area to the reactor area. A break of this type would result in the release of propylene oxide from the pipes at a release rate conservatively estimated to be 620 lbs/min. Cargill has estimated that it would take plant personnel approximately 30 minutes to respond and shut down the flow, resulting in a total release of 18,600 lbs. The modeling indicates that under urban conditions, the distance to "toxic endpoint" would be 0.3 mile. The "toxic endpoint" for propylene oxide is 0.59 mg/L. The hazard impact zone encompasses an estimated residential population of approximately 240 persons, based on the 1990 Federal Census, and estimated using EPA's Landview III database program. Public receptors in the alternative impact zone include public recreation areas and industrial/commercial areas. No environmental receptors would be affected. 4.0 ACCIDENT PREVENTION PROGRAM Some processes subject to the Risk Management Regulation are also subject to Occupational Safety and Health Administration (OSHA) Process Safety Management Standard (PSM). PSM governs the same processes and regulated substances at the site that are subject to 40 CFR Part 68. Cargill has a PSM program at the Cedar Rapids Corn Milling plant that includes the following elements: - Employee Training and Participation - Process Safety Information - Process Hazards Analysis - Operating Procedures - Training - Contractors - Pre-Startup Safety Review - Mechanical Integrity - Hot Work Permit - Mana gement of Change - Incident Investigation - Emergency Planning and Response - Compliance Audits - Trade Secrets 5.0 FIVE-YEAR ACCIDENT HISTORY In conjunction with the current RMP and PSM programs in place at the Cedar Rapids Corn Milling plant, there is a standard management practice that requires internal reporting of unusual events, including those in which any abnormal emission of regulated chemicals is observed or suspected. The incident information is reviewed and a determination is made as to whether a reportable quantity on any chemical listed as requiring reports to regulatory authorities is involved. If so, the appropriate authorities are notified. During the past 5 years (June 1994 to June 1999), there has been no accident involving any RMP regulated substance that qualifies for reporting under 40 CFR Part 68. This means that no accident has resulted in reportable on-site injury, off-site injury, emergency response, or damage to property or the environment. 6. 0 EMERGENCY RESPONSE PROGRAM Cargill's Cedar Rapids Corn Milling plant has established an Emergency Action Plan to ensure appropriate steps are taken to protect the public health and the environment, as well as the safety of the plant employees. The EAP is designed to address foreseeable emergency situations at the facility and provide appropriate hazard and emergency preparedness information to employees, contractors, emergency response personnel, and the community. Emergency situations can include fire, explosion, chemical release or spill, bomb threats, weather emergencies and other natural emergencies. Cargill has developed procedures to be followed in the event of an emergency and a command structure to evaluate an emergency to determine the appropriate action to be taken to remedy it. Cargill staff have a "First Response" capability and are able to administer basic first aid and CPR. Cargill will rely on the Cedar Rapids Fire Department, CRFD or Linn County HAZ-MAT team, and area ambulance/paramedic services for assistance as required control and resolve emergencies. Plant operation at the Cedar Rapids Corn Milling facility can present various types of potential hazards and Cargill recognizes the need to have a well trained and prepared work force to safely and effectively deal with emergency situations. A preventative maintenance program to inspect and test emergency response equipment has been established. Training programs including classroom and drills have been established to ensure responsible staff can respond to emergencies. Emergency response training exercises have included the Cedar Rapids Fire Department, CRFD or Linn County HAZ-MAT team, area ambulance/paramedic services and the LEPC. Important communication links with the community are maintained through Cargill plant staff attendance at monthly meetings with local industry and emergency response planning officials. 7.0 PLANNED CHANGES TO IMPROVE SAFETY Cargill's Cedar Rapids Co rn Milling plant, under the recent RMP program, as well as its existing PSM and earlier SARA Title III Community Right-to-Know Act compliance programs has organized its management system to effectively address foreseeable hazards and potential risks. Both the advanced planning aspects of process design, operating procedures, and emergency preparedness, and the operational elements of system maintenance, safe operating practices and ongoing personnel training are necessary to support a continual improvement in facility safety. These programs are documented so that information about safe handling of chemicals at the facility is readily available to all employees and in the event questions arise from public officials regarding potential risks to the community. All of these features of the RMP and the integrated risk management program at the Cedar Rapids Corn Milling plant lead to operations that are safe today, but will be even safer tomorrow. Cargill Cedar Rapids Corn Milling facili ty safety program incorporates continuous improvement through use of on-going evaluations of safety and programs. Risk Management Plan Executive Summary June, 1999 |