Sun Pacific Lerdo Highway Cold Storage facility - Executive Summary
EXECUTIVE SUMMARY |
Accidental Release Prevention and Emergency Response Policies
Sun Pacific utilizes anhydrous ammonia in the refrigeration system at their cold
storage facility east of Shafter, California. It is Sun Pacifics policy to comply with
all applicable governmental regulations. Further, it is Sun Pacifics objective to
be a responsible citizen of the community in all of its business activities.
Sun Pacific emphasizes safe and environmentally sound operating practices and
procedures through their employee training programs. In addition to job specific
training, operators and maintenance personnel receive training in accident
prevention, safety, and first aid. Additionally, an emergency action plan has been
prepared for Sun Pacific and a chain of command to respond to emergencies has
Sun Pacific has developed a detailed Compliance Audit Checklist which is used
to evaluate compliance with the Process Safety Management (PSM) and 40 CFR
68 (RMP regulations). At least every three years, Sun Pacific audits these
programs and any findings of noncompliance are documented and responded to
and the deficiencies are corrected.
Description of the Stationary Source and Regulated Substances
Sun Pacific owns and operates a cold storage facility located at 33374 Lerdo
Highway. Shafter is the closest city to the Sun Pacific Lerdo Highway Cold
Storage facility. The plant was constructed in 1988. The refrigeration system
has been upgraded several times, with the last expansion completed prior to
September 1, 1992.
At Sun Pacific, anhydrous ammonia is used in the refrigeration system which
provides process cooling for the cold storage facility. The system consists of a
high pressure receiver, six evaporative condensers, four compressors, three
recirculation accumulators, and numerous evaporators. The three recirculation
accumulators and evaporator units provide cooling to the cold storage rooms and
greening rooms. Flooded evaporators are utilized in the
degreening room. The halls and truck dock areas are cooled by direct expansion
During normal operation, the anhydrous ammonia is distributed throughout the
refrigeration system. However, during major maintenance activities, the entire
refrigeration system can be pumped down to evacuate the ammonia from the
system and store it in the high pressure receiver. The maximum quantity of
ammonia that can be stored in the high pressure receiver is 20,987 pounds.
For purposes of the offsite consequence analyses, the RMP regulations define
the toxic endpoint for anhydrous ammonia as 0.14 mg/l (200 ppm). This
concentration has been established by the American Industrial Hygiene
Association as the Emergency Response Planning Guideline Level 2 (ERPG-2).
ERPG-2 is the maximum airborne concentration below which it is believed that
nearly all individuals could be exposed for up to one hour without experiencin
developing irreversible or other serious health effects or symptoms which could
impair an individuals ability to take protective action.
Worst-Case Release Scenario and Alternative Release Scenario
Offsite consequence analyses are used as tools to assist in emergency response
planning. The RMP regulations require the owner or operator of a stationary
source to analyze the offsite impacts due to an accidental release of a regulated
substance. The offsite consequence analysis for a Program 3 process must
analyze the worst-case release scenario and an alternative release scenario.
Since Sun Pacifics ammonia-based refrigeration system is considered a
Program 3 process, both release scenarios were evaluated in the offsite
The offsite consequence analysis must include an estimate of the residential
population within an area potentially affected by the accidental release scenario.
This area is defined as a circle with a radius equivalent to the d
release would travel with concentrations at or above the endpoint. The circle
also defines the area in which potential environmental receptors must be
The worst case release is defined by the U.S. EPA as the total release of the
contents of the single largest vessel or pipe within 10 minutes. For liquefied
gases stored under pressure, the entire contents of the vessel or pipe are
assumed to be released as a vapor. A total vapor release is highly unlikely.
However, this standardized worst case scenario was developed for emergency
response agencies to use for planning purposes.
An alternative release scenario is a release that is more likely to occur than the
worst-case release scenario. For Sun Pacific, the alternative release scenario
was selected based on the results of the Process Hazard Analysis (PHA) for the
ammonia-based refrigeration system. A credible release event with a high
discharge rate would potentially have the greatest offsite
impact. A failure of one
of the pump seals was identified in the PHA as having a medium probability of
occurrence with a possible high discharge rate, and therefore, was chosen as the
alternative release scenario.
Sun Pacific has analyzed the offsite consequences of the worst-case and
alternative release scenarios. For the worst-case release scenario, the release
of 21,000 lbs. of ammonia over a 10 minutes period within the engine room, the
plume would travel 1.2 miles at concentrations at or above the endpoint. Using
1990 Census data, the population potentially affected within the worst-case
release scenario circle is 48 persons. There were no sensitive receptors or
environmental receptors within the worst case release scenario circle.
In the alternative release scenario, a failure of the pump seal was modeled as a
release of liquefied ammonia stored under pressure. For a release of 580 lb/min
of anhydrous ammonia within the engine room, the model calculated tha
plume would travel 0.1 mile at concentrations at or above the endpoint. No
residences are located within the 0.1 mile area around the Sun Pacific facility.
As such, there would be no population impacts from the alternative release
scenario. There were also no sensitive receptors or environmental receptors
within the alternative release scenario circle.
The ammonia refrigeration equipment, except for the evaporative condensers, is
located within a building, which would greatly reduce the impact of a release.
The modeling performed as part of this offsite consequence analysis includes a
mitigation factor which assumes that the release is within an enclosed space, in
direct contact with the outside air.
General Accidental Release Prevention Program and Chemical-Specific
A PSM program, which meets the requirements of the general accidental release
prevention program, has been developed at Sun Pacific to address the
anhydrous ammonia system. The P
SM program includes the following chemical-
specific prevention steps:
Written process safety information, including information pertaining to the
hazards of ammonia, the technology of the process, and the equipment in
the process has been compiled.
An initial Process Hazard Analysis (PHA) was performed and will be
updated and revalidated at least every five years.
Written operating procedures have been developed and implemented, and
are reviewed at least annually.
Safe work practices, such as lockout/tagout, confined space entry,
opening process equipment or piping, and control over entrance into the
facility have been developed and implemented.
Each employee involved in operating the ammonia system has received
initial training and refresher training at least every three years.
Written mechanical integrity procedures have been established and
A Management of Change (MOC) program has been developed and
implemented to address all proposed chan
ges to the ammonia system.
Pre-startup safety reviews are performed when a modification is made to
the ammonia system that is significant enough to require a change in the
process safety information.
Audits are conducted at least every three years to evaluate compliance
with the CalARP regulations.
Incident investigation procedures have been established.
A written plan of action regarding the implementation of employee
participation has been developed and implemented.
Hot work permits are issued for all hot work operations conducted on or
near the ammonia system.
A Contractor Safety Policy has been developed and implemented.
To ensure that the general accidental release prevention program and the
chemical-specific prevention steps are implemented, Sun Pacific has assigned
overall responsibility for the RMP elements to the General Manager. The
General Manager has the overall responsibility for the development,
implementation, and integration of the RMP eleme
Five-Year Accident History
Sun Pacific has not had any accidental releases from the ammonia-based
refrigeration system that have resulted in deaths, injuries, or significant property
damage on site, or known offsite deaths, injuries, evacuations, sheltering in
place, property damage, or environmental damage in the last five years.
Emergency Response Program
Sun Pacific has established an emergency action plan and a chain of command
to respond to emergencies and to notify emergency responders when there is a
need for a response. However, an emergency response program does not need
to be developed for the facility since Sun Pacific employees will not respond to
accidental releases of ammonia, the facility is included in the community
emergency response plan, and appropriate mechanisms are in place to notify
Planned Changes To Improve Safety
Based on the PHAs performed in October, 1998, the following changes were
recommended and will be impleme
nted by December, 1999.
1) Installation of ammonia detectors in the engine room and key process
2) Installation of an actuator on the 4 inch suction ball valve so that the pump
can be isolated from the accumulator with a remote switch outside of the
accumulator room in the event of a seal failure (i.e. motor operated valve
3) Consider installation of PSV between block valve and solenoid valve on
liquid line associated with accumulator #3.
Through the accidental release prevention program, Sun Pacific regularly
evaluates the need for any changes to improve safety. Currently, Sun Pacific
does not have any additional changes planned to improve safety other than the
above listed items.