Pinto Valley Operations, Copper Cities Unit - Executive Summary |
|
The accidental release prevention and emergency response policies at your facility: This facility complies with all applicable federal, state, and local laws related to the storage of ammonia. If an emergency were to occur, it is our policy to notify the Gila County Sheriff's Office. A description of your facility and the regulated substances handled: This facility is the old Copper Cities Unit of the Pinto Valley Operations, located north of Miami, Arizona. The facility is no longer in operation. However, remediation water from the nearby Pinal Creek Water Quality Assurance Revolving Fund (WQARF) site is diverted to the facility, where it is treated with ammonia to raise the pH of the incoming water, and then stored in the Diamond H open pit on the Copper Cities Unit property. This process is operated as part of an interim remedial action by the Pinal Creek Group, of which BHP is one member. Ammonia is the only regulated substance m aintained by BHP Copper in an amount in excess of the designated RMP threshold. It is stored in a single 63,200-pound tank, which is operated by Pacific Standard Specialties, Inc. Current plans call for discontinuing the use of ammonia at the facility within one to two years. The worst-case release scenario: The worst-case scenario is a tank stem knock-off, resulting in the release of the entire contents of the tank over a period of about 53 minutes. The ammonia would be released as a liquid that would immediately vaporize. According to EPA's RMPComp model, the distance to the endpoint is 2.8 miles. Although the tank is located in a classically rural environment (according to limited population and lack of urban development), the model was run in the urban mode since there are significant topographic barriers around the tank site that would inhibit the dispersion of the released ammonia. It should be noted that, due to the conse rvativeness of RMPComp and its inability to allow for the effects of topography, the real zone of impact is likely to be much less than 2.8 miles. In reality, it is highly likely that there are no defined receptors (e.g., residences, hospitals, recreation areas, etc.) within the real zone of impact. The general accidental release prevention program and chemical-specific prevention steps: This facility complies with EPA's accident prevention rule and all applicable state and local codes and regulations. The ammonia tank system is designed, installed, and maintained in accordance with state law. The tank and associated equipment are inspected periodically and each time the tank is filled. Five-year accident history: We have not had an accident involving ammonia that caused deaths, injuries, property or environmental damage, evacuations, or shelterings in place. The emergency response program: In the event of an emergency involving our ammonia system, it is our policy to notify the Gila County Sheriff's Office and request that they respond to the emergency. We have discussed this policy with the Sheriff's Office. Planned changes to improve safety: None |