Hwy AG Services - Executive Summary

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Hwy AG Services - Morristown 
 
Risk Management Plan - Executive Summary 
 
The accidental release prevention policy at Hwy AG Services involves, but is not limited to technologies, procedures, and management practices.  All applicable procedures of the ANSI K-61.1 - 1989 revision of the "Safe Requirements for the Storage and Handling of Anhydrous Ammonia," as adopted by the Minnesota Department of Agriculture are adhered to.  Our emergency response policy involves the preparation of response plans that are tailored to our facility and to the emergency response services available in our community, and is in compliance with the EPA Emergency Response Program requirements. 
 
This facility is in the business of selling anhydrous ammonia to farm customers as a form of nitrogen fertilizer.  The facility has one anhydrous ammonia storage tank, with a capacity of 30,000 gallons water capacity and two storage tanks with a capacity of 18,000 gallons water capacity each.  The storage tank, several an 
hydrous ammonia nurse tanks, risers for filling nurse tanks, electrical panels, lighting, and safety equipment are all parts of this facility's anhydrous ammonia operation.  The facility is manned during the season and is operational through normal business hours. 
 
The off-site consequences analysis includes two anhydrous ammonia release scenarios, identified as "worst-case" release and "alternative" release scenario.  The first scenario is defined by EPA and shall assume the maximum quantity of one vessel is released as a gas in 10 minutes due to a catastrophic break.  The alternative release scenario is defined as a more likely accidental release of anhydrous ammonia caused by a transfer hose failure. 
 
The "worst-case" release scenario involves a catastrophic failure of the tank, releasing the entire 140,000 pounds of anhydrous ammonia.  The off site consequences were calculated using "TFI's RMP Guidance for Ammonia Retailers".  The worst case scenario used EPA's recommended wind spe 
ed of 1.5 meters per second with a "F" atmospheric stability class.  A rural topography was selected as typical.  The distance to the endpoint was 2.90 miles. It is estimated that 2,710 people would be affected by this release. 
 
 
The "alternative release" scenario assumed a hose breaks and leaks 7,127 pounds of anhydrous ammonia.  The EPA recommended wind speed of 3.0 meters per second with a "D" atmospheric stability class was used in this scenario.  Using urban topography and "TFI's RMP Guidance for Ammonia Retailers" the toxic endpoint is 0.68 mile.  The population with in that area is estimated to be 35 people.  The assumption is that the duration of the release is 2 minutes because equipment, excess flow valves, and human intervention will stop the leak.   
 
Hwy AG Services has had no anhydrous ammonia leaks within the past five years.  Even though the company has had no releases it still coordinates annual visits with the local fire department to review the systems and procedures  
for response to a leak. 
 
Hwy AG Services has several key elements in its accident prevention plan: 
1. The anhydrous ammonia system adheres to the laws and regulations that are based on the 1989 revision of the ANSI K61.1 adopted in 1990 by the State of Minnesota. 
2. Annual training is required of all personnel on handling, transferring, or transporting anhydrous ammonia.  The training includes properties of ammonia, safe handling practices, first aid, and emergency response. 
3. Use of good management practices as specified by industry standards and training aids. 
4. Frequent site inspections by management and safety consultants. 
5. Annual inspections by the Minnesota Department of Agriculture fertilizer inspectors include safety equipment, tanks, and handling equipment. 
6. Use of proper anhydrous ammonia personal protective equipment and safety equipment. 
 
Changes are made in the system when necessary or when required by regulation change.  Periodic evaluations of the procedures help t 
o determine whether or not a change in operations should be made to provide increased safety to the operators and to the community.
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