Mesa Water Treatment Plant - Executive Summary
This executive summary provides a brief overview of the Risk Management Program (RMP) and the associated policies at the Mesa Water Treatment Plant (Mesa WTP), one of several facilities owned and operated by the Colorado Springs Utilities (CSU).
Accidental Release Prevention and Emergency Response Policies
CSU has determined that this facility is required to comply with RMP Program 2. CSU believes that it is important to provide a safe workplace to its employees and minimize the impact of its operations on the surrounding community and the environment. Accordingly, CSU has developed proactive safety and environmental programs, which are reliant upon active employee participation and management leadership and support. This same proactive philosophy was employed in the development and implementation of the Mesa WTP RMP for the chlorine system.
The RMP prevention program is arguably the most important element of the rule. Its program elements require the active participation of faci
lity employees and management in conducting activities aimed at preventing accidental releases of regulated chemicals. If prevention activities could be completely successful, there would be no need for emergency response activities, since no releases would occur. Accordingly, a well-developed and properly-implemented prevention program will lower the possibility of an accidental release and minimize the consequences of a release should one occur.
CSU takes an active role in preventing accidental releases at all of its facilities by ensuring that its employees are well-informed regarding the hazards associated with the regulated processes (e.g., chlorine at the Mesa WTP) and actively participated in comprehensive process hazard analyses. The system employees are properly trained in the safe operation of the covered processes and the safe handling of treatment chemicals. They are aided in this work by complete, understandable system operating procedures.
CSU management understands
its duty to provide a safe working environment and to take measures to prevent accidents that may have an effect on the surrounding community. This understanding is reflected in procedures described and referenced in the Mesa WTP RMP procedures and policies.
As for emergency response, CSU has established and maintains procedures for emergency notification and response. These are reviewed with employees on a periodic basis and revised to accommodate changes in staffing when they occur.
Stationary Source and Regulated Substances
The Mesa WTP is located at 2715 Mesa Road in Colorado Springs, El Paso County, Colorado. The Mesa WTP is a surface water treatment plant consisting of the following processes: pre-chlorination, coagulation, flocculation, sedimentation, filtration, post-chlorination, and stabilization. Pre-chlorination uses an initial dose of chlorine to disinfect the incoming water and to maintain a chlorine residual throughout the treatment process. Post-chlorination is
required to boost the chlorine level to maintain disinfection throughout the distribution system.
The Mesa WTP serves approximately 100,000 people with an average winter flow rate of 15 million gallons per day (MGD) and an average summer rate of 38 MGD.
The Mesa WTP utilizes chlorine as a disinfecting agent in the treatment of drinking water. The chlorine is stored in one-ton containers with a maximum intended inventory of ten containers (20,000 pounds) on site. Therefore, the Mesa WTP is regulated under Program 2 of the RMP rule due to the volume of chlorine stored and used at the facility.
Worst-case and alternative release scenarios have been determined after careful review of the regulation and consideration of the storage vessel configuration at the facility. For worst-case release scenario, the regulation is clear. The assumption is that a full one-ton container of chlorine is released over a ten-minute period. No active mitigation may be considered. T
herefore, the scrubber is assumed not to work in this scenario. Worst-case meteorological conditions as specified in the RMP regulation are also assumed to be present. The release is also assumed to occur outdoors.
For the alternative release scenario, the facility reviewed the consequences of the loss of a fusible plug from a full one-ton container during offloading activities. The incident would occur outdoors so that the scrubber or other active mitigation devices would not be effective.
Results of the off-site consequence analyses are described in Sections 2 and 3 of the RMP*Submit plan for the Mesa WTP.
Prevention Steps for Chlorine
The prevention program and chemical-specific prevention steps are described in detail in the Mesa WTP RMP manual. The prevention program includes the following elements:
7 Safety information, which includes information pertaining to the hazards of chlorine in the process, process technology, and process equipment
7 Hazard review, which includes a
systematic evaluation (by an employee team) of: the hazards of the chlorine process, identification of previous process incidents, engineering and administrative controls, consequences of failure of the engineering and administrative controls, facility siting, human factors, and possible safety and health effects of failure of controls
7 Operating procedures, which include steps for each operating phase, operating limits, safety and health considerations, and safety systems and their functions
7 Training for each Mesa WTP employee involved in operating the chlorine system
7 Computerized maintenance program including schedules and job plans to maintain the on-going integrity of the chlorine process equipment
7 Compliance audits at least every three years from 1999 to evaluate Mesa WTP RMP compliance
7 Incident investigation, to be conducted and documented for each incident that resulted in, or could have reasonably resulted in, a catastrophic release of chlorine from the Mesa WTP
addition to these elements, the chlorine storage facility at Mesa WTP is equipped with a chemical scrubber. In the event of a release of chlorine in the storage room, the normal ventilation system shuts down and the chlorine-contaminated air is sent to the scrubber for neutralization. The scrubber is maintained and tested on a regular basis to ensure proper operation during a chlorine release event.
Within the five-year period prior to the submittal of this RMP, there were no accidental releases of chlorine meeting the requirements of 40 CFR 68.42.
Emergency Response Program
This facility has established and maintains an emergency response program, which includes an evacuation plan. The program is coordinated with local response agencies, including the City of Colorado Springs Fire Department and Hazardous Materials Response Team. The program is described in detail in the Mesa WTP RMP manual and meets the requirements of 40 CFR 68.95, which include facility notif
ication of emergency responders and evacuation. The goals of the program are to protect onsite employees from the hazardous effects of chemical releases and to minimize the effects of releases on the general public. The program is routinely reviewed and updated to reflect personnel and regulatory changes. CSU works closely with the Colorado Springs LEPC and other local industries and agencies to coordinate local response activities.
Planned Changes for Improved Safety
Ideas for changes to improve safety are actively sought from employees. Employee meetings that focus on safety issues are held regularly at the Mesa WTP. Employees are encouraged and trained to recognize hazards and to present ideas to eliminate them or to minimize the potential consequences of those hazards.