Town of Mayodan Wastewater Treatment Plant - Executive Summary
Hydro Management Services |
Mayodan, North Carolina
Wastewater Treatment Plant
RMP Executive Summary
Hydro Management Services has implemented a comprehensive program to safely manage chlorine at its Mayodan Wastewater Treatment Plant located in Mayodan, North Carolina. There have been no chlorine incidents in the most recent five-year history period.
To comply with the EPA's Risk Management Program (RMP), the initial step was to develop a prevention program as required by the RMP and by the OSHA Process Safety Management (PSM) regulations. This prevention program was initiated at the Plant using a consulting organization. An RMP/PSM Compliance Manual was developed for the site.
Key items included in the manual are:
-Written site specific procedures for Employee Involvement, Management of Change, Incident Investigation, Pre-Startup Reviews and Self Audits;
-Chlorine safety information as required by the regulations;
-Standard Operating Procedures for chlorine management; and
lorine system maintenance procedures.
Additional steps have been implemented to complete the PSM program:
-Training on PSM and its key components including Management of Change, Mechanical Integrity and Incident Investigation;
-Conducting Process Hazards Analyses for the three chlorine processes;
-Developing an initial Emergency Response Plan; and
-Training in support of the certification of operators.
The Plant Superintendent and company Safety Officer are meeting several times per year to review and update procedures and to maintain compliance with all aspects of the PSM/ RMP regulations.
In addition to PSM compliance, the plant has implemented a number of programs to improve the safe handling of chlorine and other chemicals.
-The chlorine delivery system at the plant has been upgraded to vacuum processes. This process has proven to reduce leaks by reducing the amount of equipment that is exposed to pressurized chlorine.
-Plant inventories are controlled to maintai
n only one cylinder connected to the process and one cylinder in reserve.
The site's Emergency Response Plans (ERP) have been significantly upgraded. In 1999, the ERP was revised to include offsite response and communication. The County LEPC and other local response organizations have been incorporated into the ERP. Where necessary, communication plans have been developed to notify businesses or residences that may be impacted by a release. Chlorine Response Drills are routinely conducted.
To further understand chlorine risks, a consulting firm was contracted to conduct "Offsite Consequence" Modeling Analysis, as required by EPA's Risk Management Program. Both a "Worst Case" and an "Alternative Case" chlorine release scenarios were studied for each site.
The "Worst Case" modeling showed the potential impact of a full, 2000 pound cylinder of chlorine released in 10 minutes. This resulting chlorine plume extended 1.3 miles. For the "Alternative Case,@ a more typical possible relea
se of 180 pounds, three pounds/minute for 60 minutes, was modeled. The modeling indicated that a plume extending 0.1 miles would result.
The modeling showed that the risk of chlorine exposure is low due to the favorable location of the plant. The Wastewater Treatment Plant is located approximately 0.85 miles southeast of the Mayodan Town Hall. Due to the topography, vegetation and adjacent surface waters, the effects of the release will be mitigated at this site to a significant degree. The most likely scenario would be for the chlorine to flow west through dense vegetation falling 75 feet downhill into the Mayo River, where it would remain in or around the river until dissipated. Thus, a chlorine release should result in no public exposure to minimum public exposure.
In addition to Process Safety Management, the organization has an active safety program. Hydro Management Services has an active Safety Committee. The committee meets monthly and its duties include reviewing new safety
procedures, accident investigations, safety surveys and safety communications.
At the Wastewater Treatment Plant, there are monthly safety meetings to review an OSHA subject or discuss a safety issue. Routine training is conducted for topics such as:
- Hazard Communications
- Personal Protective Equipment
- Confined Space
As a result of our programs, the plant has had an excellent safety record with no recordable injuries over the past three years. As mentioned earlier, there have no reportable chlorine releases from the plants in the last five years. The plant has worked extensively to upgrade its safety program. Report by:
Director of Operations
Hydro Management Services, Inc.