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PCBs Persist Federal Regulations Prompt Storage Site Decommissioning
November, 2008
By Steven Biggs
The Ontario government has committed $56 million in funding over two years to remove and destroy PCB-contaminated materials from its Pottersburg PCB storage site in London, Ontario. The 11-acre containment facility is owned and operated by the Ontario Ministry of the Environment (MOE) and consists of four storage cells housing approximately 35,500 cubic metres of PCB-contaminated materials - equal to approximately 2,100 truckloads.
PCB is the acronym given to polychlorinated biphenyls, a group of persistent synthetic chemicals with properties that permit them to migrate from industrial sites into waterways. From an industrial standpoint, PCBs offer a desirable stability, but this same stability means that they don't biodegrade and can accumulate in the environment.
"It's an extremely stable chemical, which is one of its best characteristics, and one of its worst," says Camille Atrache, General Manager at Tri-Phase Environmental Inc., a hazardous waste removal firm. "PCBs are heavier than water. They sink in water. When they get into the groundwater they move down."
The Pottersburg storage site was originally created by Westinghouse Canada in 1984 to store PCB-contaminated material from its property. It was then transferred to the Ontario Ministry of the Environment in 1985 to accommodate additional contaminated soil and sediments from the cleanup of the nearby Pottersburg Creek and Walker Drain.
CONTAINMENT vs. DESTRUCTION OPTIONS
Contaminated materials are now kept in place using non-permeable synthetic and clay liners, along with a leachate collection mechanism. A leak-detection zone and monthly monitoring ensure proper functioning of the containment mechanisms.
Alternatively, the cost of effective methods for destroying PCBs has dropped by almost two-thirds over the past decade. This, coupled with new federal regulations, led to the decision to decommission the site.
A request for proposal process is underway to choose a contractor to decommission the site. This will include removal of the sediments and soils in the storage cells, along with the cell structures. It is expected that all waste will be removed by the end of October 2009. Backfilling with clean soil will ready the site for future industrial use.
Destruction of the PCBs and decontamination of the site must adhere to strict procedures and regulations. If improperly burned, PCBs can yield toxic furans and dioxins.
"They are very stable compounds and destruction methods must be able to break the molecular bonds," says Tina Dufresne, the MOE's District Manager in London.
Thermal destruction methods use high temperatures to break down those bonds. Solvents can be used to decontaminate metal components of transformers, rinsing the PCBs from the metal. The solvents then undergo thermal destruction.
New federal regulations mandate destruction of stored PCBs, but they do not specify the means. "We don't know which method of destruction will be used until the contract has been awarded," Dufresne notes.
The MOE has set up public web pages with background information on the site and project, along with an e-mail newsletter. Ministry spokesperson Kate Jordan reports approximately 1,065 visits to the website between August and early November 2008, while 88 people have registered for the newsletter. The chosen contractor will be responsible for continuing the communication with the surrounding community through meetings and a web site.
The MOE also established the Pottersburg Community Liaison Group to represent community interests during the removal of PCB-contaminated material. Thus far, the group has focused on details of the tender, but its role will expand to include encouraging community input throughout the project.
HANDLING DECOMMISSIONED EQUIPMENT
Sites such as Pottersburg store contaminated material from manufacturing processes, but decommissioned equipment containing PCBs must also be properly stored. The importation and manufacture of PCBs was banned in Canada in 1977, but they are still found in older electrical equipment such as ballasts, transformers, and capacitors.
"There's a lot of PCB-containing equipment that is still in use," Atrache says. Buildings owners/managers have to follow the appropriate procedures when such equipment is taken out of service.
"Once you decommission a piece of equipment you have 30 days to store it or dispose of it," Atrache says. "If you plan to store it, you have to set up a proper PCB storage site."
In Ontario, for example, that means registering the storage site with the Ministry of the Environment, keeping records, having fire alarms, and having a spill contingency plan. Property managers who don't want to set up a registered storage site can hire a registered firm to remove PCB materials, which are then taken to an approved facility for storage and destruction.
Steven Biggs is a freelance journalist based in Toronto.
PROHIBITION IN SENSITIVE ZONES AFTER 2009
The new federal PCB regulations that came into force in September 2008 stipulate that PCBs currently located in designated sensitive areas must be sent to an approved destruction facility by the end of 2009.
As is often the case in Canada, different levels of government are involved in PCB regulation. The federal government, through the Canadian Environmental Protection Act, determines how PCBs are assessed and managed - including allowable levels, handling, use, manufacture, production, and disposal. Provincial governments oversee storage, transportation, and destruction.
Areas around hospitals, educational institutions, water treatment facilities, food processing plants and medical care facilities have been deemed sensitive, meaning that stored PCBs must be moved to a facility where they will be destroyed and PCB-containing equipment must be decommissioned. "If buildings are in sensitive areas the mandate is to get rid of and destroy that PCB by December 31, 2009," says Ken De, a PCB co-lead at Environment Canada.
DEADLINES
Sensitive Area Non-Sensitive Area
50 - 499 ppm 500+ ppm 50 - 499 ppm 500+ ppm
Decommission equipment
with PCBs Dec. 31, 2009 Dec. 31, 2009 Dec. 31, 2025 Dec. 31, 2009
Decommission ballasts
with PCBs Dec. 31, 2025
Destroy
PCBs in storage Dec. 31, 2009 Dec. 31, 2009 Dec. 31, 2009 Dec. 31, 2009
Source: Canada Gazette
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