San Leandro Milk - Executive Summary
Accidental Release Prevention and Emergency Response Policies |
The management and staff of the San Leandro Milk Plant are committed to operating the Plant with the highest regard for the safety of the public, Plant personnel, and the environment. To ensure the safety of the public, Plant personnel, and the environment, the Plant has implemented a management system that integrates the elements of OSHA's Process Safety Management (PSM) standard, 29 CFR 1910.119 and EPA's Risk Management Program (RMP) rule, 40 CFR part 68. The policies and procedures integrated under the Plant's management system specifically address prevention of the release of anhydrous ammonia, and emergency response to an accidental release of ammonia.
Description of Processes, and Regulated Substances Handled at the San Leandro Milk Plant
The San Leandro Milk Plant produces fluid milk and other products that require refrigeration. Anhydrous ammonia is used as a refrigerant in the mechanical compression refrigera
tion system at the San Leandro Milk Plant. Ammonia is handled in a closed-loop process that consists of the following general stages: Liquid storage; Expansion; Evaporation; Compression; and Condensation.
Mechanical refrigeration is a physical process, rather than a chemical process: the ammonia undergoes no chemical changes in the refrigeration cycle. Heat is removed from the product being refrigerated or frozen as ammonia changes phase from liquid to vapor. By reliquefying the ammonia vapor, the ammonia can be used continuously in the refrigeration cycle.
The ammonia refrigeration system is the only process at the San Leandro Milk Plant which is subject to the EPA RMP rule (and the OSHA PSM standard, and the CalARP program). Anhydrous ammonia is the only regulated substance handled in the ammonia refrigeration system.
At ambient temperature and pressure, ammonia is a colorless gas with a characteristic, irritating odor. Ammonia is highly soluble in water. Ammonia is the th
ird highest-volume chemical produced in the United States. The chemical formula of ammonia is NH3. Anhydrous ammonia is handled both as a pressurized liquid at ambient temperature and as a refrigerated liquid within the San Leandro Milk Plant refrigeration system.
The toxic endpoint to which the consequences of ammonia releases must be analyzed is 0.14 mg/L. This is approximately equal to 200 ppmv, which corresponds to the American Industrial Hygiene Association's Emergency Response Planning Guideline level 2 (ERPG-2) for ammonia. ERPG-2 is the maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms which could impair an individual's ability to take protective action.
Worst-case Release Scenario, and Alternative Release Scenarios
The Plant's worst-case release scenario consists of a total release of the maximum allowable in
ventory of the High Pressure Receiver over a duration of ten minutes. The maximum allowable inventory is approximately 17,000 pounds. The maximum allowable inventory is the largest quantity of ammonia that could be contained in the High Pressure Receiver without allowing the vessel to become liquid-full at 115 degrees Fahrenheit, which corresponds to the vessel's pressure relief set point of 250 psig.
The High Pressure Receiver is located within a building. In accordance with "Risk Management Program Guidance for Ammonia Refrigeration," the release rate to the surroundings was calculated as 600 lbs/min, with a duration of 10 minutes.
EPA's "Risk Management Program Guidance for Ammonia Refrigeration" was used to evaluate the worst-case release scenario. The following inputs were applied: wind speed, 1.5 m/s; stability class, F; topography, urban; release duration, 10 minutes; release rate, 600 lbs/min. The maximum distance to the toxic endpoint was evaluated as 0.9 miles.
Landview III, the population within 0.9 miles of the release point was estimated as 3,400. The following types of public receptors lie within 0.9 miles of the release point: schools, residences, and major commercial/office/industrial areas. There are no environmental receptors, as defined in the RMP rule, within 0.9 miles of the release point.
EPA's "Risk Management Program Guidance for Ammonia Refrigeration" was used to evaluate the alternative release scenario. The Plant's alternative release scenario consists of a pressurized liquid ammonia release through a <" diameter hole in outdoor piping downstream from the evaporative condenser. The release is assumed to persist for 10 minutes prior to isolation (which can safely and rapidly be accomplished remotely). The pressure in the piping is assumed to be 130 psig, at a temperature of 25 degrees C. Under these conditions, the release rate was found to be 110 lbs/min, and the total quantity released was 1100 lbs.
The following i
nputs were assumed: wind speed, 3 m/s; stability class, D; topography, urban. Combining these inputs with the release rate described above, the distance to 200 ppmv ammonia was found to be 0.1 mi. Note that the EPA guidance conservatively assumes that the release occurs at ground level. A release from the elevation of the evaporative condenser would actually be accompanied by dilution due to vertical dispersion, resulting in a somewhat shorter distance to the toxic endpoint.
The population within 0.1 is estimated to be 40. The following types of public receptors lie within the distances to the endpoints described above: residences, and major commercial/office/industrial areas. There are no environmental receptors, as defined in the RMP rule, within 0.1 miles of the release point.
Accidental Release Prevention Program
The Plant's accidental release prevention program consists of the following elements: Process Safety Information; Process Hazard Analysis; Operating Procedures; T
raining; Contractors; Pre-Startup Safety Review; Mechanical Integrity; Hot Work Permit; Management of Change; Incident Investigation; Compliance Audits; and Employee Participation. The purpose and scope of each element is briefly described below.
Process Safety Information - The purpose of compiling the required Process Safety Information is to enable Plant personnel who work with the ammonia refrigeration system to identify and understand the hazards posed by ammonia refrigeration. The Plant's Process Safety Information procedure addresses: Information requirements pertaining to the hazards of ammonia; Information requirements pertaining to the technology of the process; Information requirements pertaining to the equipment in the process; and Process Safety Information accessibility requirements.
Process Hazard Analysis - The purpose of the Plant's PHA procedure is to describe the method for conducting process hazard analyses of the Plant's ammonia refrigeration system. The Plan
t's PHA procedure addresses: PHA methodology; PHA scope; PHA team requirements; Employee participation requirements; System established to promptly address the PHA team's recommendations; PHA update and revalidation requirements; PHA report retention requirements; and PHA report distribution requirements.
Operating Procedures - The purpose of the Plant's Operating Procedure policy is to provide a method for developing and implementing written operating procedures to give clear instructions for safely conducting activities associated with the Plant's ammonia refrigeration system. The Plant's Operating Procedure policy addresses: Development and implementation of written procedures to provide clear instructions for safely conducting activities involved in each covered process; Development and documentation of process operating limits; Development and documentation of process safety and health considerations; Operating procedure accessibility requirements; Operating procedure review r
equirements; and Safe work practice requirements for employees and contractors to provide for control of hazards during operations.
Training - The purpose of the Plant's Training procedure is to ensure that personnel involved in operating the Plant's ammonia refrigeration system have received and understood training in: an overview of the Plant's ammonia refrigeration system; the operating procedures required in the Operating Procedures element of the Plant's PSM program; safety and health hazards associated with the Plant's ammonia refrigeration system; and applicable safe work practices. The Plant's Training procedure addresses: Initial training requirements; Refresher training requirements; Documentation of employee training; and Testing to ensure that required training has been understood.
Contractors - The purpose of the Plant's Contractors procedure is to establish a method for ensuring that all contractors are adequately trained to perform work on or near the Plant's ammoni
a refrigeration system. The Plant's Contractors procedure addresses the responsibilities of the Plant and the contract employer with respect to ensuring the safety of contractors working on or near the Plant's ammonia refrigeration system.
Pre-Startup Safety Review - The purpose of the Plant's Pre-Startup Safety Review procedure is to ensure that new or modified facilities that handle regulated substances are safely started up. The Plant's Pre-Startup Safety Review procedure (PSSR) addresses: PSSR Checklist completion prior to startup of new or modified facilities; The method for determining when a PSSR shall be performed, and PSSR Team selection; The system to ensure that new Process Safety Information has been compiled; The system to ensure that all materials and construction are in accordance with design specifications; The system to ensure that all safety, operating, maintenance, and emergency procedures are in place and adequate; The system to ensure that a Process Hazard Anal
ysis has been performed for new facilities, and that recommendations have been addressed prior to startup; The system to ensure that Management of Change requirements are met prior to start-up of modified facilities; The system to ensure that operations and maintenance employees are trained prior to start-up; and Documentation of the Pre-Start Safety Review.
Mechanical Integrity - The purpose of the Plant's Mechanical Integrity policy is to establish the requirements of the Mechanical Integrity program at the San Leandro Milk Plant. The purpose of the Mechanical Integrity program is to ensure that process equipment used to handle anhydrous ammonia is designed, constructed, and maintained to minimize the risk of accidental release. The Plant's Mechanical Integrity program addresses the following activities as they relate to the Plant's ammonia refrigeration system: Training in the Plant's ammonia refrigeration system and its hazards, and in the safe conduct of maintenance activities
; Inspection and testing; Correcting deficiencies in equipment; and Quality assurance in fabrication, installation, and maintenance.
Hot Work Permits - The purpose of the Plant's Hot Work Permit procedure is to define how Hot Work Permits are issued and to ensure compliance with permit requirements before and during hot work. The Plant's Hot Work Permit procedure addresses: General requirements; The Hot Work Permit; Authorization of hot work; Fire prevention precautions; and Fire watchers.
Management of Change - The purpose of the Plant's Management of Change procedure is to establish the Plant's requirements for managing changes to the Plant's ammonia refrigeration system. This procedure provides direction in identifying, reviewing, and authorizing process changes prior to their implementation in order to minimize their potential impact on safety and health. The Plant's Management of Change Procedure addresses the following: Identifying process changes; Reviewing process change
s; Training necessitated by process changes; Updating Process Safety Information; Updating operating procedures; and Authorizing process changes. Specific actions included within reviewing process changes are: documenting the technical basis for the proposed change; assessing the impact of the proposed change on safety and health; modifying operating procedures, as necessary; and documenting and tracking the intended duration of the change (temporary vs. permanent).
Incident Investigation - The purpose of the Plant's Incident Investigation procedure is to provide a method for reporting, investigating, and preventing reoccurrence of incidents that result in or could reasonably have resulted in a catastrophic release of ammonia. The Plant's Incident Investigation procedure addresses: Reporting incidents; The procedure for initiating an incident investigation; The establishment of an Incident Investigation Team, and requirements for the selection of Team members; Investigating the i
ncident; Preparation of the Incident Investigation Report and the minimum requirements of the Report; The system established to promptly address and resolve the report findings and recommendations; and The method for reviewing the findings of the Incident Investigation with all operating, maintenance, and other affected personnel (including contract employees) whose work assignments are relevant to the findings.
Compliance Audits - The purpose of the Plant's Compliance Audits procedure is to establish the requirements for an audit that verifies that the Plant is meeting the requirements of OSHA's Process Safety Management (PSM) standard, and EPA's Risk Management Program rule. The Plant's Compliance Audits procedure requires triennial review of the Plant's PSM program/RMP Prevention Program procedure documents, and evaluation of the implementation of these procedures by conducting records reviews, employee interviews, and field inspections. The Plant's Compliance Audit procedure als
o requires that recommendations be formulated to resolve any identified deficiencies. The Plant's Compliance Audits procedure addresses: Pre-audit activities; Conduct of the PSM program/RMP Prevention Program compliance audit; and Post-audit activities, including taking action to resolve any identified deficiencies.
Employee Participation - The purpose of the Plant's Employee Participation procedure is to document the method of actively involving Plant employees in the development and conduct of the Plant's Process Safety Management elements. The purpose of involving employees in the development and conduct of the Plant's PSM elements is to foster commitment to the enhancement of process safety. The Plant's Employee Participation procedure addresses: The method of consulting employees (and their representatives) on the conduct and development of each element in the Plant's process safety management program; and The method for providing employees (and their representatives) access
to all process safety management documents and records.
Five-year Accident History
Over the past five years, the San Leandro Milk Plant has not had any ammonia releases that resulted in deaths, injuries, property damage, environmental damage, or offsite evacuations.
Emergency Response Program
The Plant has an emergency action plan that addresses the following: Evacuation; Emergency release notification; and First aid/medical management. The Plant's emergency response program is coordinated with the local fire department.
All Plant employees receive training in the emergency action plan. The local fire department is invited to participate in the Plant's emergency action plan drills, in order to familiarize fire department personnel with the Plant's process and emergency procedures.
Planned Changes to Improve Safety
As a result of the Plant's most recent internal compliance audit, the San Leandro Milk Plant has completely restructured its PSM program/prevention program. The n
ew program elements have been integrated into a management system framework, in accordance with internationally recognized principles of total quality management. The management system is designed to ensure implementation of each program element, in compliance with the OSHA PSM standard, and the EPA RMP rule. Authority, responsibility, and accountability are clearly and specifically assigned to Plant management, supervision, and staff. The means of documenting compliance have been improved for each prevention program element.