Minn-Dak Yeast Company, Inc. - Executive Summary

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Accidental Release Prevention and Emergency Response Policies 
 
The Minn-Dak Yeast Company is committed to the protection of its employees, the greater community and the environment from any hazardous substances used in its yeast manufacturing process, specifically aqueous ammonia.  It is the policy of Minn-Dak Yeast Company to comply with all Federal, State and Local laws. 
 
Facility Description and Regulated Substance Handled 
 
The Minn-Dak Yeast Company operates a yeast manufacturing facility located in Wahpeton, Richland County, North Dakota.  Aqueous ammonnia, at 30% concentration, is a key component in the manufacture of yeast.  The liquid ammonia is fed into the sealed process and is completely used during the process.  The maximum amount of aqueous ammonia stored on-site is 120,000 pounds. 
 
Worst Case Scenario 
 
The worst case scenario defined by the RMP Guidance is a failure of the ammonia storage tank resulting in the release of the entire maximum inventory of 120,000 pounds in 1 
0 minutes.  Under these conditions the EPA look-up table, Exhibit 4-9, in Section 4.1 of the Risk Management Program Guidance for Wastewater Treatment Plants document indicates the distance to toxic endpoint is 2.5 miles for a release rate of 2,400 pounds per minute (.02 x 120,000 and rounded up to 2,500 pounds per minute to match the table amount).  According to the Environmental Data Resources, Inc. (EDR) receptor report 0374867.1r dated May 28, 1999, the estimated population within the 2.5-mile radius is 2292 people. 
 
Alternate Case Scenario 
 
The alternate case scenario is defined by the EPA as arelease that is more likely to occur than the worst case scenario.  For the Minn-Dak Yeast Company facility this release is the failure of a one-inch diameter liquid ammonia line.  The EPA look-up table, Exhibit 4-22, in section 4.2 of the Risk Management Program Guidance for Wastewater Treatment Plants document indicates a 0.2-mile distance to toxic endpoint for a release rate of 100 pounds 
per minute.  The release rate calculation used Bernoulli's formula found in Section 4.2 of the guidance document which was then rounded up to 100 to correspond to the table amount.  A population density of 117 people per square mile was derived from the EDR receptor report for the worst case scenario.  It is estimated that the population within the 0.2-mile radius is 15 people. 
 
General Accident Release Prevention Program 
 
Through completion of this RMP, the Minn-Dak Yeast Company has complied with the EPA requirements under 40 CFR Part 68.  Process safety information and operations/maintenance procedures are documented on site.  Periodic functions such as process hazard analysis, training, change management and incident investigation are conducted on a regular basis.  Audits of the overall RMP will be conducted on a regular basis to assure compliance with EPA regulations. 
 
Five-Year Accident History 
 
The Minn-Dak Yeast Company has had one aqueous ammonia related injury occur to one o 
f its employees.  The injury was not serious, a momentary exposure to ammonia vapor, and was due to a process valve failure.  No ammonia accidents causing death, environmental or property damage, evacuations, or in-place sheltering have occured in the last five years at the yeast manufacuring facility. 
 
The Emergency Response Program 
 
In the event of an emergency, it is the policy of the Minn-Dak Yeast Company to notify the local (City of Wahpeton) Fire Department and evacuate all employees from the facility.
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