City of Lawrenceburg Water Filtration Plant - Executive Summary
LAWRENCEBURG WATER PLANT |
A. The Lawrenceburg Water Treatment Plant accidential release prevention policy involves a unified approach that integrates technologies, procedures, and management practices. All applicable procedures
of the U.S. Environmental Protection Agency (EPA) Prevention Program are adhered to. The Lawreneburg
Water emergency response policy involves the preparation of response plans which are tailored to the facility and to the emergency response services available in the community, and is in compliance with the
EPA Emergency Response Program requirements.
B. The Lawreneburg Water Treatment Plant gets its water from Shoal Creek and Hope Springs. The treatment process includes the use of Chlorine and Alum. The Chlorine is housed in an enclosed building. The Building contains (4) ton Cylinders of Chlorine. Various types of saf
ety equipment, monitoring devices and control devices are housed within the building, as well as access to safety equipment inside and outside of the building. The facitlity is monitored 18 hours daily by onsite personel and call out alarm 7 days a week.
C.1 The offsite consequence analysis includes consideration of two(2) chlorine scenarios identified as
"worst case release" and "Alternative release". The first scenario as defined by EPA, which states the "owner or operator shall assume that the...maximum quality int he largest vessel...is released as a gas over 10 minutes", due to an unspecified failure. The alternative scenario is defined as "more likely to occur tha the worst case scenario."
Atmospheric dispersion modeling has to be performed to determine the distance traveled by the chlorine
released before its concentration decreases to the "toxic endpoint" selected by EPA of 3ppm, which is the emergency Response Planning Guideline Level 2 (ERPG-2). This defined by the Ame
rican Industrial Hygiene Association (AIHA) as the "maxium airborne concentration below which it is believed that nearly
all individuals could be exposed for up to one hour without experiencing or developing irreversible or other
serious health effects or symptoms which could impair an individual's ability to take protective action."
The residential population within a circle with a radius corresponding to the toxic endpoint distance has
to be defined," to estimate the population potentially affected."
The worst case scenario at the Lawrenceburg Water Plant involves total loss of ton cylinder during
delivery of chlorine, dropping a one ton cylinder onto concrete from 5 feet during inloading, shearing valve.
The offsite worst consequence analysis for this scenario was performed by EPA's RMP Comp Program including worst case scenarious for chlorine. The conditions pre-defined by EPA, namely release of the
entire amount as a gas in 10 minutes, use the one hour average as the toxic en
dpoint, and consideration of the population residing within a full circle radius corresponding to the toxic endpoint distance. EPA
mandated meteorological conditions, namely Stability F, wind speed of 1.5m/sec, and 77 F.
Cl.1 When atmospheric dispersion modeling for the worst case scenario was performed on chlorine using
the EPA assumptions, a distance to toxic endpoint of 0.9 miles (1.4km) and an estimate of residential
population potentially affected of 250 was obtained.
C1.2 The alternative release scenario involves a leaking valve on a one(1) ton chlorine cylinder. The
chlorine released is 1800 pounds, at an average rate of one hour, of 30 pounds/minute. Toxic endpoints were obtained using EPA RMP COMP Program. The EPA mandated meteorological conditions used were Stability Class D, wind speed 3 meters/second, average air temperature of 77F. The estimated distances traveled to toxic endpoint 0.1 miles (0.2km).
Activation of the chlorine detectors is an active mitigation m
easure that should be considered. The chlorine monitors will detect chlorine and give an alarm at 1 ppm and above. The monitors are connected to the telemetry system for a remote monitoring system. A fixed chlorine monitor is located in the chlorine cylinder storage room.
D. The general Lawrenceburg Water Plant accidential release prevention program is basedon the following key elements:
HIgh level of training of the operators
Preventative maintenance programs
Use of Safety Equipment
Use of accurate and effective operating procedures, written with the participation of the operators.
Performance of a hazard review of equipment and procedures.
Implementation of an auditing and inspection program.
Chemical specific prevention steps include availability of self-contained breathing apparatus (SCBA),
awareness of the hazardous and toxic properties of chlorine and sulfur dioxide, as well as proper
training of on site personne
l in case of release.
E. Though we have had (3) Accidental releases in the last (5) years , quick response by the operators and the Lawrenceburg Fire Department prevented the loss of any equipment or injuries.
F. The facility has an emergency response program coordinated with the Lawrenceburg Fire Department and Police Department depending uon the size of the leak, weather conditions, wind speeds and direction.
If advanced level of technical assistance is deemed necessary to control leak, Chemtrec may be called to
give advice and assistance via 24 hour emergency number. PB & S Chemical has a team that can be
activated with a one hour notice 24 hours a day. A mock emergency response drill for chlorine loss has
been conducted on site, where current response and emergency operations were utilized.
G. We have in place a chlorine and sulfur dioxide emergency action and process safety management plan
dated January 16, 1997. No revisions have been found necessary at this time.
Mock emergency drills proved the plan in place was efficient and thorough.