Texarkana Mill - Executive Summary
RISK MANAGEMENT PLAN |
40 CFR 68
INTERNATIONAL PAPER COMPANY - TEXARKANA MILL
International Paper Company owns and operates the Texarkana pulp and paper mill located in Cass County, Texas. The Texarkana Mill produces bleached papergrade kraft and is permitted to produce 817,803 air dried unbleached tons of pulp per year (ADUBT/yr). Pulp is bleached via an elemental chlorine free process using chlorine dioxide and other chemicals.
An Accidental Release Prevention Program has been codified under Title 40, Part 68 of the Code of Federal Regulations (40 CFR 68), and referred to herein as the Risk Management Program (RMP) rule. The RMP includes three major parts: hazard assessment, prevention program, and emergency response program.
RMP Regulated Substances
The Texarkana Mill has identified two toxic chemicals used at the mill which are listed in 40 CFR '68.130. The chemicals occur in processes, as defined by 40 CFR '68.3, such that the quantity in the process excee
ds corresponding threshold quantities specified in 40 CFR '68.130. The toxic chemicals that are covered (i.e., regulated) by the RMP rule include chlorine dioxide and chlorine.
Solvay and single vessel process using methanol (SVPM) processes generate aqueous chlorine dioxide solution (ClO2) for the bleaching process at the Texarkana mill. Under 40 CFR Part 68, a process, which stores or handles an aqueous solution with a concentration greater than or equal to the de minimis concentration (1% by weight) and a total quantity greater than or equal to the threshold quantity (1,000 pounds), is regulated by the RMP rule. The generated aqueous ClO2 solution is pumped to four large outdoor tanks for storage and process use at a maximum concentration of 10 g/L (1% by weight). Tanks 1 and 2 are located within a common dike. Tank 1 has a maximum storage capacity of 105,800 gallons of solution (8,800 pounds ClO2) and Tank 2 has a maximum storage capacity of 188,000 gallons of solution (15,70
0 pounds ClO2). Tanks 3 and 4 are also located within a common dike that is separate from Tanks 1 and 2. Tanks 3 and 4 each have a maximum storage capacity of 200,000 gallons of solution (16,700 pounds ClO2). Therefore, ClO2 in the bleaching process is covered by the RMP rule.
Chlorine is stored for water treatment in standard one ton (2,000 pounds) cylinders. In one location, 18 cylinders are arranged in three parallel outdoor storage racks of six cylinders per rack. At any one time, at least one rack of cylinders (i.e., six cylinders) is interconnected through a supply header. This interconnection yields a process quantity of at least 12,000 pounds, which exceeds the RMP threshold quantity for Cl2 of 2,500 pounds. In another location at the facility, five one ton Cl2 cylinders are stored together in a rack, but only two cylinders are connected to a supply header. This interconnection yields a process quantity of at least 4,000 pounds, which exceeds the RMP threshold quantity
of 2,500 pounds Therefore, two covered processes apply to chlorine.
Five Year Accident History
There have been no accidental releases of regulated substances from a covered process from the Texarkana Mill in the past five years that have resulted in death, injury, or property damage on-site, or known off-site impacts (deaths, injuries, evacuations, sheltering-in-place, property damage, or environmental damage).
Worst-Case Release Scenario
The worst-case release scenario for toxic chemicals is based upon the catastrophic failure of a 200,000 gallon ClO2 (1% wt. ClO2 solution) storage vessel. A catastrophic failure of a storage vessel would release 16,700 pounds of ClO2 and could impact the following off-site receptors:
Major commercial, office, or industrial areas; and
Devices used to contain ClO2 spills and minimize off-site impacts include:
The catastrophic failure of a one ton Cl2 cylinder was also assesse
d as the potential worst-case release scenario for toxic chemicals. The off-site impacts from a Cl2 release were found to be bounded within the off-site impacts from a ClO2 worst-case release.
Alternative Release Scenario
The alternative release scenario for ClO2 is assumed to result from a pipe leak which would release ClO2 solution (1% wt. ClO2). It is assumed that the leak would be detected and stopped within 15 minutes releasing a total of 1,252 pounds of ClO2 during a 22 minute volatilization period. The following off-site receptors could be impacted:
Major commercial, office, or industrial areas.
It was assumed that no mitigation devices other than detecting and stopping the leak would be used to minimize off-site impacts.
The alternative release scenario for Cl2 is assumed to result from the failure of a thermal plug on a one ton cylinder which would release liquefied Cl2 until the liquid level in the cylinder drops below the thermal plug. At this point,
the gaseous Cl2 would be released from the cylinder. A total of 1,800 pounds would be released over a 29 minute period. The following off-site receptors could be impacted:
Major commercial, office, or industrial areas.
It was assumed that no mitigation devices would be used to minimize off-site impacts.
Accidental Release Prevention Program
The three processes applicable to RMP requirements are covered by the facility's PSM program and the prevention program for these processes consist of the 14 elements of process safety management as required by OSHA 1910.119.
Emergency Response Program
The Texarkana Mill is fully equipped to handle process emergencies and coordinates with local emergency responders, as necessary. Local emergency responders are trained for emergencies that may be encountered at the mill.
Planned Changes to Improve Safety
The Texarkana Mill is continually improving its operations to provide a safe work environment. Such improvements includ
e training, alarm systems, mitigation measures, and thorough incident investigation/corrective action programs.