Boise Cascade - Executive Summary
Per the requirements of Section 112(r) of the Clean Air Act Amendments of 1990 as codified in Title 40 of the Code of Federal Regulations (CFR) Part 68, this Risk Management Plan (RMP) is submitted to the United States Environmental Protection Agency (U.S. EPA) in a timely manner for the Boise Cascade St. Helens, Oregon facility, which handles one or more regulated substances listed in Appendix A of Part 68. |
1.1 STATIONARY SOURCE & REGULATED SUBSTANCES HANDLED
Boise Cascade owns and operates a pulp and paper mill located in St. Helens, Oregon, which is an existing major stationary source per the requirements of Title V of the Clean Air Act Amendments of 1990. The regulated substances handled by this facility are chlorine, and chlorine dioxide, all of which are considered hazardous by the US Environmental Protection Agency (U.S. EPA).
The St. Helens mill produces pulp and paper from wood chips and sawdust using the Kraft process. Chlorine and chlorine dioxide are used in the bleach
process to remove lignin from the fibers and to whiten the pulp; chlorine is also used to treat water entering the process.
Liquid chlorine is stored in rail cars prior to use and fed to a vaporizer, and gaseous chlorine is then led to the process. The maximum quantity of chlorine that can be stored or handled at this facility is 720,000 pounds, or four rail cars.
Chlorine dioxide is generated on site by the R-8 process which uses sodium chlorate, methanol, and sulfuric acid as a raw materials; these chemicals are not regulated under the risk management plan. The generated chlorine dioxide is absorbed into water stored as a dilute aqueous solution (10 g/l). The maximum quantity of chlorine dioxide that can be stored or handled at this facility is 39,713 pounds.
1.2 ACCIDENTAL RELEASE PREVENTION & EMERGENCY RESPONSE PROGRAMS
Boise Cascade takes a systematic, proactive approach to preventing accidental releases of hazardous chemicals. The St. Helens mill uses several managemen
t systems and adheres to industry and national standards to meet this goal.
The use and storage of chlorine and chlorine dioxide at the St. Helens mill is covered by the OSHA Process Safety Management (PSM) standard (29 CFR 1910.119). Boise Cascade adheres strictly to the PSM standard and focuses many of its safety efforts around PSM. The PSM program requires Boise Cascade to take specific efforts to identify and mitigate process hazards, including:
? Providing process and chemical safety information to employees,
? Performing process hazard analyses,
? Writing and implementing written operating procedures,
? Training process operators on the safe operation of equipment,
? Identifying and maintaining critical process safety equipment,
? Managing and communicating process changes,
? Performing pre-startup safety reviews,
? Performing internal audits of compliance with the PSM standard,
? Investigating accidents to find root causes and preventing future accidents,
? Involving employee
s in the PSM process,
? Requiring permits for hot work, and
? Implementing a safety program for contractors.
Although an accidental chemical release is unlikely, Boise Cascade prepares for releases and other emergencies. The St. Helens mill has developed a written response plan which is discussed is detail in Section 1.5. Boise Cascade employees routinely practice responding to simulated releases and emergencies, and coordinates with community responders such as the St. Helens fire department.
1.3 WORST-CASE & ALTERNATIVE RELEASE SCENARIOS
The Boise Cascade St. Helens facility has constructed a worse-case and alternate (i.e. more credible) release scenario for each regulated chemical.
CHLORINE: WORST-CASE SCENARIO
The failure of the largest storage tank (i.e. railcar) when filled to the greatest amount allowed would release 180,000 pounds of chlorine (nominal capacity of railcars). Since the contents of the railcar are under pressure, the release is assumed to be a liquid jet
that volatilizes to gas upon release from the tank. The entire contents of the railcar are assumed to release at a constant rate over a ten minute period.
CHLORINE DIOXIDE: WORST-CASE SCENARIO
The failure of either of the large chlorine dioxide solution storage tanks would release 238,00 gallons of chlorine dioxide solution, or 19,856 pounds of chlorine dioxide. Company policy limits the maximum filling capacity of the large chlorine dioxide storage tanks to 90%; the 238,000 gallon figure is 90% of the physical capacity of the tank. It is assumed that the entire contents of the tank are released and instantaneously form a pool 1 cm deep. The chlorine dioxide volatilization rate from the pool is calculated according to a model based on an evaporative pool model.
CHLORINE: ALTERNATE SCENARIO
A 1" pipe conveys liquid chlorine to the water treatment plant from the chlorine expansion tank. This pipe could be ruptured by a vehicle (e.g. forklift) striking the pipe bridge which contain
s the chlorine pipe. This would release 310 pounds of liquid chlorine that is assumed to vaporize instantly. The release is estimated to take twelve seconds.
CHLORINE DIOXIDE: ALTERNATE SCENARIO
A fiberglass pipe which conveys chlorine dioxide from the large storage tanks to the bleach plant is assumed to be damaged by mechanical impact during a pump replacement or other maintenance work. A 3" diameter hole is made in the pipe and chlorine dioxide solution is released. The motive force is the gravity head of the tank; it is assumed that the pump is shut off immediately during the evacuation of the area. The release continues for twenty minutes until a response crew can enter the required protective equipment and shut off the release. A drain in the vicinity of the pipe is assumed to be able to capture 2 gallons per second of the spill; this is directed to a gas-tight sump where the spilled material can be collected and treated.
1.4 FIVE YEAR ACCIDENT HISTORY
The Boise Cascade S
t. Helens facility has had one release of a regulated material that resulted in an injury in the last five years. On May 5, 1995, a contract employee was injured when exposed to chlorine leaking from a hose.
There have been no releases of regulated materials which have resulted in deaths, significant property damage, or any known offsite deaths, injuries, evacuations, sheltering in place, property damage, or environmental damage in the last five years.
1.5 EMERGENCY RESPONSE PROGRAM
In addition to the prevention program, Boise Cascade has developed and implemented a written emergency response plan to effectively respond to accidental chemical releases. This plan identifies roles for plant personnel in the event of a number of different scenarios. The plan includes specific tasks for key personnel during responses, emergency plant shutdown procedures, steps to contain and handle releases of specific materials, specific information on how to contact community response agencies and
the public, and information on training employees and community responders in safe response techniques.
The St. Helens mill trains regularly on its emergency plan. This training includes general mill employees, members of Boise Cascade's response team, and community responders. Training exercises are evaluated, and the plan is updated when deficiencies are identified.
Boise Cascade maintains an emergency response team that is trained to respond to many different types of emergencies. The team is made up of workers from different shifts and is always ready to respond. The team regularly conducts response drills, often including community responders.
1.6 PLANNED CHANGES TO IMPROVE SAFETY
Boise Cascade has identified no major unresolved process hazards in the chlorine or chlorine dioxide systems. No major revisions to those processes are currently planned. However, Boise Cascade follows a policy of continuous process safety improvement.