Farmers Co-op Grain & Lumber Company - Executive Summary

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The United States Environmental Protection Agency (USEPA) developed the  
Risk Management Program (RMP) rule (40 CFR 68) to assist facilities in  
preventing accidental releases of highly toxic or flammable chemicals.   
The RMP established three levels of requirements for the program.   
Programs 1 and 2 are for facilities that pose less risk to the  
environment and therefore have reduced compliance requirements.   
Program 1 is designed for "no impact" facilities and has the fewest  
requirements, while Program 3 is the most stringent of the three  
levels. 
 
The program level for each facility is determined by: 
 
      Use of regulated substances in threshold quantity 
 
      Impact of an off-site public receptor (e.g., residence, school, 
      park) 
 
      North American Industrial Classification System (NAICS) code 
 
      Five-year accident history 
 
      OHSA PSM (29 CFR 1910.119) applicability.  
 
This facility is regulated under Program 2 requirements under 40 CFR  
68.10 because: 
 
 
      It stores anhydrous ammonia and propane in excess of the  
threshold 
      quantity 
 
      A release from this facility could impact an offsite public  
receptor 
      (residence) 
 
      It does not operate under a NAICS code specified in the rule 
 
      It is not subject to OSHA PSM (this is a retail facility). 
 
40 CFR Part 68 Subpart G applies to an owner or operator of a  
stationary 
source that has more than a threshold quantity of a regulated substance  
in a process, as determined under 40 CFR 68.115 Farmers Co-op Grain &  
Lumber Company stores more than the threshold quantity of anhydrous  
ammonia and propane (10,000 pounds) for commercial sale.  Therefore,  
Farmers Co-op Grain & Lumber Company is required to submit a Risk  
Management Plan (RMP) as defined in 40 CFR 68.150 by June 20, 1999. 
 
The Farmers Co-op is committed to operating in a safe and compliant  
manner. Employees involved in operating the ammonia and propane storage  
facility are thoroughly traine 
d to identify and understand the hazards  
posed by this the transfer process.  Process safety and emergency  
response materials are kept on site and periodically reviewed.   
Information includes information pertaining to the hazards of ammonia  
and propane, process technology, process equipment, and emergency  
response procedures. 
 
The stationary source is the Farmers Co-op Grain & Lumber Company  
anhydrous ammonia and propane storage facility.  The largest ammonia  
process group (e.g., largest storage tank or group of interconnected  
tanks) has a storage capacity of 60,000 water gallons (280,000 pounds).   
The total ammonia stationary storage capacity is 280,000 pounds.  The  
facility also stores numerous smaller transportable tanks (nurse tanks)  
that are actually used in the fertilizer application process.   
 
The facility also has 48,000 water gallons (176,000 pounds) of propane  
is a single process.  The total propane stationary storage capacity is  
176,000 pounds. 
 
The facility is 
required to complete one worst-case release scenario  
per hazardous substance handled [68.165(a)(2)] to determine program  
applicability.  Farmers Co-op has chosen to use the DEGADIS+ release  
model and RMP Comp (Version 1.06) to determine offsite impacts. 
 
 
For this facility, a worst-case release would occur in the event that  
the largest ammonia and propane storage tanks would rupture and the  
entire contents would be released to the atmosphere in 10 minutes.  The  
worst-case scenario requires a ground-level release height (0 feet).   
Ammonia release rate for use of DEGADIS+ is presented below: 
 
 
Sample Ammonia Endpoint Calculation 
 
Given:       Storage Tank Capacity is 60,000 water gallons 
            ANSI K61.1 filling density = 56 % (of water wt.) 
 
Release Rate = Tank Capacity / 10 minutes 
            =(60,000 gal * 8.345 lb/gal water)*(0.56)  / 10 min  
           = (500,700 lb)*(0.56) / 10 min 
           = 280,000 (rounded) / 10 min 
           = 28,000 lb/min  
 
Calculations 
for the worst-case propane release follow the same method. 
 
Results of Worst-Case Ammonia Release Scenario 
 
Input of the preceding data into the DEGADIS+ release model, the  
results indicate a worst-case impact of  2.8 (rounded) miles for the  
facility.  The worst-case model output summary is included at the end  
of this section.  The rule defines the toxic endpoint of anhydrous  
ammonia to be 0.14 mg/L. 
 
The residential population within a 2.8 mile radius of the facility is  
800 (rounded) based on the 1990 US Census data.  
 
Results of Worst-Case Propane Release Scenario 
 
Input of the preceding data into the RMP Comp program, the results  
indicate a worst-case impact of  0.40 (rounded) miles for the facility.   
The rule defines the explosive endpoint of propane to be 1 psi  
overpressure.  The residential population within a 0.40 mile radius of  
the facility is 9 (rounded) based on the 1990 US Census data.  
 
The facility is required to complete one alternate release scenario per  
regul 
ated chemical per 40 CFR Part 68.165(a)(2).  The alternative  
release scenario considered is in accordance with the guidelines  
provided in 40 CFR 68.22 and 68.28. 
 
The alternative scenarios chosen for this facility involves a release  
because of a sudden split in the hose during transfer.  While this  
scenario is still unlikely because the transfer hoses used have  
multiple layers of rubber and a layer of braided stainless steel wire  
underneath the outer sheath (to prevent abrasions, cuts, and splits) it  
is more likely than the worst-case as required by 40 CFR 68.28(b)(i).   
This scenario is also the 
most likely to occur, since overfilling is prevented by a return vapor  
line to the tank truck making the delivery.  The transfer hose rupture  
area is assumed at 0.5 square inches.  Because personnel are always  
present at the facility during transfer, Farmers Co-op personnel will  
respond within 10 minutes.  Release rate was calculated using the OCAG  
tank release equation (Section 8. 
1.1).  Propane release is calculated  
with a similar equation found in the Risk Management Program Guidance. 
 
Results of Ammonia Alternative Release Scenario 
 
There are 3 people located within 0.23 miles from the facility.  Thus,  
this alternative release scenario satisfies the conditions of '68.28.  
 
Results of Propane Alternative Release Scenario 
 
Input of the preceding data into the RMP Comp program, the results  
indicate an alternate case impact of 0.05 miles for the facility.  The  
residential population within this radius is 0 
 
The facility maintains written process safety information to enable  
employees involved in handling ammonia and propane to identify and  
understand the hazards posed by this process.  Written information  
includes physical properties of ammonia and propane, health risks  
associated with ammonia and propane exposure, and material safety data  
sheets.  In addition, the facility has conducted and/or implemented the  
following: 
 
            hazards review 
 
         standard operating procedures 
            training program 
            maintenance program 
            compliance audits 
            incident investigation      
 
The Farmers Co-op Grain & Lumber Company anhydrous ammonia and propane  
facility in Humphrey  has had no recordable accidents within the past  
five years.  
 
Recommendations for safety improvements were identified in the hazard  
review which was completed April 12, 1999.  Recommendations were  
identified for two categories: Standard Operating Procedures, and  
Training.  Safety improvements will be investigated concerning their  
impacts on other systems and/or procedures prior to implementation.   
Additional recommendations may be made upon review of any accidents  
and/or when the hazard review is updated every five years.
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