During Phases I and II, custodians made significant progress in remediating contaminated sites: activities were undertaken on 1,590 sites. Risks were reduced by treating contaminated water and soil and removing and destroying hazardous wastes.
The following are some examples of federal contaminated sites where funding for remediation during these first two phases produced notable results:
Phase II Success Stories:
- Soil Remediation at the Forillon National Park of Canada Operational Centre
- Colomac Mine Remediation Project
- Soil Remediation on a First Nation Reserve: Kitasoo Remediation Project
- Rock Bay Remediation Project
Phase I Success Stories:
- Bushell Public Port Facility Remediation Project
- From Dump to Destination : Revitalizing Cartier-Brébeuf National Historic Site of Canada
- Swallowtail Lightstation Remediation Project
- Wilmer Marsh Remediation Project
- FOX-C Ekalugad Fjord Remediation Project
- Penhold Transmitter Bunker Remediation Project
- Oshawa Harbour Remediation Project
Soil Remediation at the Forillon National Park of Canada Operational Centre
Name and Location: Forillon National Park of Canada, Quebec
Custodian: Parks Canada Agency (PCA)
Forillon National Park of Canada, established in 1970, is a mountainous peninsula bordered by the Gulf of Saint Lawrence and Gaspé Bay. The operational centre of Forillon National Park, in use since the creation of the park, has several buildings dedicated to administrative activities and the maintenance of the park.
There were concerns that some former service facilities – including some fuel-storage tanks and piping first installed in the 1970s – had never been removed, and might have contaminated the soil around Buildings 14 and 15.
In the autumn of 2009, an environmental review of the history of the operational centre revealed the presence of three underground tanks near Building 15 and a pumping station near Building 14. The presence of petroleum hydrocarbons in the soil was then confirmed by a Phase II environmental site assessment and a subsequent study in 2010.
These soil-characterization studies determined the extent of the potential contaminants. The volume of affected soil was estimated to be 260 m3. Moreover, the presence of the pumping station raised some concerns about the presence of underground pipes and the possibility that there could be spills or accidental hydrocarbon leaks. There was concern that this could pose a risk to human health and the environment, including groundwater.
After comparing various remediation techniques, Parks Canada commissioned an excavation-and-disposal approach, because it would be cheaper, faster and, most importantly, more effective in achieving remediation goals.
The contractor, under the supervision of Parks Canada and Public Services and Procurement Canada, carried out excavation and disposal in the autumn of 2012, targeting the areas south of Building 15 and the building in sector 20, near the island of pumps. When the water accumulated in excavations showed exceedances of petroleum hydrocarbons, the team pumped it into a tanker, then analyzed and disposed of it at an authorized site. Ultimately, 630 metric tonnes of contaminated soil was remediated. The project was completed in 2013 with the refurbishment of the premises.
Remediation work has allowed Parks Canada to manage environmental issues and human health while reducing environmental liabilities at the site. By preventing the spread of accidental contamination by petroleum hydrocarbons, the remediation of the operations centre has helped to preserve the ecological integrity of Forillon National Park.
Colomac Mine Remediation Project
Name and Location: Colomac Mine, Northwest Territories
Custodian: Indigenous and Northern Affairs Canada (INAC)
The Colomac Mine was an open-pit gold mine that operated sporadically between 1990 and 1997. The mine site is located 220 km north of Yellowknife, on lands traditionally used by the Tlicho people. INAC assumed responsibility for the site in 1999, after the mine operator was placed in receivership and abandoned the site. The site consisted of a main facility area, three open pits, two large waste-rock piles, a tailings-containment area, an airstrip, and access roads. Numerous environmental and physical hazards were left at the Colomac Mine after operations ceased, invoking emergency measures under the Northwest Territories Waters Act in 1999 and 2000 to manage highly contaminated water within the tailings-containment area that was threatening to overtop a dam.
The Colomac Mine Remediation Project was inherently risky because of the site’s remoteness and limited access, extreme weather conditions with short field and construction seasons, and many natural and occupational hazards. The project team made identifying and managing these hazards a priority from the beginning. INAC worked closely with the Tlicho in all aspects of the project, involving them as partners in the management of the site and selection of remediation options. The Department also hired Tlicho businesses as much as possible under available procurement mechanisms, and leveraged the care and maintenance and remediation work programs for training and capacity building. Traditional knowledge was of particular significance to the project, primarily during the evaluation, selection, and implementation of remediation options. INAC also completed widespread human-health and ecological risk assessments in consultation with the Tlicho. The outcome was a remedial action plan developed for the site in 2004.
The plan detailed remediation methods for each of 16 project components. Remediation was completed mainly through a contract for major civil works and a contract for the final remediation and restoration of the site. Key objectives for overall management of the Colomac site were also achieved through care and maintenance contracts.
Major civil works took place over the 2006–2007 field season (accelerated by one year), and included construction of covers on exposed tailings, a new dam, a spillway around one of the dykes, and a discharge channel to allow treated water to flow from Tailings Lake to the downstream environment.
The final remediation and restoration contract addressed most of the remaining objectives of the project over the 2010–2011 field season. This included decontaminating and demolishing mine infrastructure and ancillary buildings, rehabilitating petroleum hydrocarbon-contaminated sediments at nearby Steeves Lake, excavating and treating contaminated soils, hazardous and non-hazardous waste disposal, drainage restoration, general regrading, and installation of site-access controls for the post-closure phase of the site.
Significant achievements during the overall management of the project included large scale demolition and civil earth works, hydrocarbon remediation, and the in situ remediation of major water bodies, with techniques involving the addition of phosphorus in the form of monoammonium phosphate.
The Colomac Mine Remediation Project has been recognized for its contribution to a safer environment for the Tlicho people and all northern residents. In 2013, the project won the Consulting Engineers of Alberta’s Award of Excellence in the Environmental category; and, in 2014, the Canada Land Reclamation Association highlighted the re-vegetation of the site in its scientific journal.
All remediation components identified in the 2004 remedial action plan were effectively completed as of 2011–2012, the first year of Phase II of FCSAP. Remediation was largely completed within budget and with significant employment and training opportunities for Indigenous and other northerners, who benefited from over 75% of the employment hours and over 90% of the training hours. Since 2012–2013, the Colomac Mine site has been undergoing long-term monitoring.
Soil Remediation on a First Nation Reserve: Kitasoo Remediation Project
Name and Location: Kitasoo, British Columbia
Custodian: Indigenous and Northern Affairs Canada (INAC)
The community of Klemtu, situated within Kitasoo Indian Reserve No. 1 on Swindle Island of coastal British Columbia, is accessible by water taxi, weekly ferry or seaplane and is home to approximately 400 residents. Klemtu is predominantly residential, with limited commercial development; as hydroelectric power is limited, the community is highly dependent on fuel oil for home heating.
In October 2008, a fuel-oil spill from a residential oil tank occurred at the Kitasoo post office, releasing an unknown quantity of fuel. A subsequent environmental site assessment confirmed contamination of the soil and groundwater, but to a greater extent than could be attributed to the spill alone. INAC funded additional reserve-wide Phase I and Phase II environmental site assessments, which identified extensive contamination by hydrocarbons and metals (such as lead, copper, arsenic and zinc) in the soil, groundwater and sediments throughout the reserve. Elevated metal concentrations were also found in the marine sediments of nearby Trout Bay. Furthermore, in 2011, the community discovered that 24 of its buildings, of which 22 are residential homes, were constructed using creosote pilings, which emit naphthalene vapour, a known carcinogen, as they degrade.
The historic (pre-1998) sources of the reserve-wide contamination likely originate from several sources: leaks from above-ground tanks that fuelled oil-fired furnaces; a leaking fuel-distribution system servicing various community facilities; improper hazardous and solid-waste practices, such as burning garbage; negligent fuel-handling and transfer procedures, and improper on-shore boat-repair and maintenance activities.
The areas of contamination cover most of the village, and residents risk exposure to metals through dust inhalation, ingestion of soils and traditional foods, and dermal contact; and exposure to petroleum hydrocarbons, including creosote, through dermal contact and inhalation.
The Kitasoo/Xai’xais Chief and Council, the Kitasoo/Xai’xais Health Centre, Health Canada, and INAC have worked together on the environmental investigation and the resulting remediation activities. They have also held information sessions with community members.
In 2012, Kitasoo/Xai’xais First Nation and INAC’s British Columbia regional office implemented the emergency remediation of 12 of the creosote-affected homes and properties, several areas of severe hydrocarbon contamination, and an area that posed a contamination risk to fish. In 2012–2013, they began remediation of the remaining high-risk contaminated areas and instituted corrective measures to eliminate the sources of the contaminants. These measures included the closure of the landfill; implementation of a community solid-waste management plan; construction of a waste transfer station; replacement of faulty above-ground fuel-storage tanks; and improvements to fuel-handling equipment, training and practices.
Once this remediation is complete, INAC will conduct a human-health risk assessment of any residual contamination; an ecological risk assessment of Trout Bay, which residents use for shellfish harvesting; and a long-term plan for monitoring and community management. The Department’s priority in implementing these measures is to protect the health and safety of Kitasoo/Xai’xais First Nation members.
The remediation project brought several other improvements to the community, including local employment, social well-being, self-sufficiency, economic prosperity, and acquisitions or upgrades to community assets, such as the new waste-transfer station. The community itself is now stronger, as the Kitasoo/Xai’xais First Nation has adjusted its governance model, adopted a new housing strategy and community plan, increased its capacity for environmental management, and instituted a community-supported recycling program. Finally, the remediation has been an opportunity to improve the relationship between INAC and the First Nation.
Rock Bay Remediation Project
Name and Location: Rock Bay, British Columbia
Custodian: Transport Canada (TC)
The Rock Bay Remediation Project (the Project) is located in Victoria Harbour which is situated near the downtown core of Victoria, British Columbia as well as within the traditional territories of both the Esquimalt Nation and Songhees Nation. The Project entailed remediating approximately 1.73 hectares of contaminated upland soils and 2.02 hectares of contaminated harbour sediments. The contaminated sediments represent some of the most contaminated sediments in all of Victoria Harbour.
The Rock Bay Site, and adjacent property owned by the BC Hydro and Power Authority (BC Hydro), was the location of a former coal gasification facility which operated from the 1860s to the early 1950s. The long history of gas production at Rock Bay resulted in extensive impacts to the site’s soil, groundwater and harbour sediments. The main waste product of the coal gasification process was coal tar, which contains polycyclic aromatic hydrocarbons (PAHs) which are highly toxic and a known carcinogen. The coal tar appears to have been directly discharged into the bay and used as back fill throughout the upland area. Tests also found metals and other types of hydrocarbons such as fuel. Groundwater results showed impacts from the hydrocarbons and metals. Using the Canadian Council of Ministers of the Environment (CCME) National Classification System for Contaminated Sites, Rock Bay was determined to be a Class 1 (action required) contaminated site.
From 1996 to 2003, Transport Canada and BC Hydro undertook a cooperative approach to assessing and developing a remediation strategy. From 2004 to 2006, during Phase I of the Federal Contaminated Sites Action Plan, Transport Canada and BC Hydro jointly completed Stages 1 and 2 of the three-stage project, which included the remediation of 50,300 tonnes of hazardous waste soils, 74,100 tonnes of non-hazardous waste soils and 78,500 tonnes of contaminated soils above commercial land use levels.
In 2009 Transport Canada completed remediation of two sediment hotspots at Barclay Point located at the head of Rock Bay. Approximately 250 tonnes of hazardous waste were removed with a caisson dredging technique.
The final Stage of the Project, Stage 3, undertaken by Transport Canada involved the removal and disposal of 78,000 tonnes of contaminated and 15,000 tonnes of non-contaminated soil and sediment from the bay and foreshore. To accomplish this required:
- Installing shoring along the property boundaries to remove the contaminated soil at depths of up to 8 metres in some locations
- Installing a temporary coffer dam
- Draining the bay for removal of contaminated sediments in dry conditions
- Temporary diversion of two significant stormwater outfalls past the work area
- Removal and transport of contaminated sediment and soil for off-site destruction and disposal at approved facilities
- Restoring the bay and shoreline following the Fisheries and Oceans approved habitat restoration plan
Stage 3 construction began in spring 2014 and was completed in early 2016. Final post-remediation monitoring and reporting is expected to be complete by January 2017. The approved habitat restoration plan requires 5 years of post-construction monitoring to ensure the restored marine habitat is functioning as intended.
Following completion of the post-remediation monitoring and reporting, the upland portion of the site will be sold to the Songhees Nation and Esquimalt Nation. A clean Rock Bay will allow a site that sat vacant for many years to be returned for use within the community.
Bushell Public Port Facility Remediation Project
Name and Location: Bushell Public Port Facility Remediation, Saskatchewan
Custodian: Transport Canada (TC)
The Bushell Public Port Facility was built in 1951, on the southeastern shore of Black Bay on Lake Athabasca in Saskatchewan. The site consists of two lots having a combined area of 3.1 hectares with both upland and water lots. The facility was used until the mid-1980s to supply various goods and services to local mines as well as petroleum products to the communities of Bushell and Uranium City. As the mines closed and Bushell and Uranium City shrank in size, marine activity at the Bushell facility decreased to the occasional barge.
As a result of historical operations such as unloading, storing, and loading bunker C fuel oil at the facility and a large spill in the 1980s, the site contains contaminated soil, blast rock, bedrock, spilled fuel and sediment impacts in Black Bay. The contamination of the sediments extends outside the waterlot boundaries.
Following numerous environmental site and risk assessments, Transport Canada’s Pacific Region Environmental Services developed a Remedial Action Plan in early 2005 to address the contamination. The Plan called for the excavation of the oil-soaked blast rock and contaminated soil.
Where oil had impregnated the bedrock within cracks and fissures, the bedrock was to be blasted and removed. The excavated contaminated soil, blast rock and bedrock were to be crushed in preparation for treatment by low-temperature thermal desorption, a process where the contaminated media would be put through an incinerator to burn off the oil residue. This method was initially chosen as it was more cost effective than other treatment strategies given the remote northern location of the facility.
When tendering the remediation contract in early 2005, a sustainable development component was incorporated into the bid process, resulting in an alternative remedial option being revealed. A local contractor was aware of Saskatchewan Highways’ plan to resurface the Uranium City Airport runway within the next few years, and proposed the opportunity to recycle the oil-contaminated rock and soil from the Bushell facility for use in the runway project. Given that Saskatchewan Highways would be quarrying and crushing new material and then applying oil to the crush in preparation for sealing the runway, this was considered a win-win opportunity.
Saskatchewan Highways was contacted and an agreement was reached where Transport Canada would crush and mix the contaminated soil and rock to meet the required specification for the runway resurfacing, then transport it to the airport where Saskatchewan Highways would take ownership of the material. This option cost $1,750,000 less than the original plan for incineration. Cost savings for Saskatchewan Highways estimated around $1 million. Considering the fuel savings, primarily from the incineration process that would have required nearly 1 million litres of diesel fuel, this solution reduced greenhouse gas emissions by approximately 2600 tonnes.
In 2006 another sustainable opportunity to use the aggregate was identified and Transport Canada signed an agreement with the Saskatchewan Research Council in order to transfer aggregate to the Council to be used in its reclamation of the Cold War Legacy Uranium Mine and Mill Sites.
Remediation of the upland was completed between 2005 and 2007. The 2002 ecological risk assessment of the waterlot bed sediments was updated following the uplands remediation. The sediment risk assessment update, for ecological and human health risks, included several sediment, water quality and fish tissue monitoring events between 2007 and 2009. The results of the sediment risk assessment can be used to guide future requirements at the site. The uplands have been returned to the province of Saskatchewan. A long term monitoring event is planned for 2018.
From Dump to Destination : Revitalizing Cartier-Brébeuf National Historic Site of Canada
Name and Location: Cartier-Brébeuf National Historic Site of Canada, Québec
Custodian: Parks Canada Agency (PCA)
After years of hard work and dedication, Parks Canada has given new life to a historic site in the heart of Quebec City and revitalized an aquatic ecosystem.
Created in 1972, Cartier-Brébeuf National Historic Site of Canada commemorates Jacques Cartier’s first overwintering in North America, as well as the establishment of the first Jesuit residence in Quebec City by Father Jean de Brébeuf. Used for years as a fill zone and dump site, the soil around Cartier-Brébeuf Park and the banks of the intersecting Lairet River were contaminated, and the site posed a hazard to visitors and wildlife alike. It was an area in desperate need of rescue.
As part of the restoration project, the Parks Canada team stepped briefly back in time: the site was returned to its configuration at the time of Jacques Cartier, and soil was analyzed. After an analysis of the ecological and toxicological risks and an environmental assessment, site cleanup began with the excavation and removal of nearly 3,000 m3 of contaminated soil to authorized sites. The park site and river banks were then re-naturalized through the planting of trees, shrubs, and aquatic plants in an effort to rebuild the damaged ecosystem.
The park’s scenic pedestrian trails, bike path and new interpretation pavilion led to Cartier-Brébeuf Park winning an Award of Excellence from the Canadian Society of Landscape Architects. Not only is the architecture beautiful but it is now a place where residents, families, and cultural groups can get outside and enjoy nature safely. And it’s not just people who have benefitted from the park’s revitalization! With the removal of contaminated soil and the revival of the aquatic ecosystem, wildlife such as carp, the great blue heron, the American black duck, the mallard and the double-crested cormorant have returned to the area, making this project another environmental success.
Swallowtail Lightstation Remediation Project
Name and Location: Swallowtail Lightstation, Grand Manan Island, New Brunswick
Custodian: Fisheries and Oceans Canada (DFO)
The majority of the contaminated sites for which the Department of Fisheries and Oceans (DFO) is responsible are coastal lightstations with metal contamination from the historic use of lead based paint. Remediation at these lightstations can be challenging as many are found in remote locations, making traditional remediation options, such as the excavation and off-site disposal of soil, logistically and financially unfeasible. In 2008, to evaluate the feasibility of using innovative remediation technologies for the on-site treatment of contaminated soils at these locations, DFO performed a pilot-scale demonstration of an on-site soil washing technology at the Swallowtail Lightstation located on Grand Manan Island, New Brunswick. This project was funded under the Federal Contaminated Sites Action Plan (FCSAP).
The site assessments performed at the Swallowtail lightstation identified approximately 2,000 m3 of soil having metal concentrations exceeding the Canadian Soil Quality Guidelines. The maximum concentrations of lead and barium in these soils were 67,400 mg/kg and 8,730 mg/kg, respectively. In addition, leachate concentrations were found to be above the levels that would allow the soil to be placed in a landfill. The subsequent human health risk assessment determined that the lead target concentration, below which the site would be considered safe for both the current and potential future land use as a seasonal tourist operation, was 870 mg/kg.
A patented soil washing process was tested at the site. The resulting treated soil had lead concentrations ranging from undetectable to 400 mg/kg with an average lead concentration of 119 mg/kg. Using physical separation techniques, the process separated these fine, contaminated particles from the larger uncontaminated particles. The unit used on the site was a scaled-down version of a mobile soil washing unit, which could be airlifted to the site using a Canadian Coast Guard Bell 212 helicopter.
In total, 1,700 tonnes of soil were processed using the mobile soil washing system. Approximately 1,615 tonnes of treated soil were deemed to have low enough concentrations to be returned to the excavated areas at the site. Approximately 85 tonnes of soil were placed in one-tonne tote sacks and airlifted off the island for further treatment.
The results of the on-site soil washing remediation project at Swallowtail demonstrated that this technology can be successfully used to treat soil contaminated with metals at remote locations. Many lessons learned and best practices were compiled on the challenges posed by the remote location of the site, the weather, and the transportation of equipment to the site.
Wilmer Marsh Remediation Project
Name and Location: Wilmer Marsh, Columbia Wildlife Area, British Columbia
Custodian: Environment and Climate Change Canada (ECCC)
The Wilmer Marsh Unit of the Columbia National Wildlife Area (NWA) is located 5 km south of Radium, B.C. on a remnant river benchland. The site includes an uplands bench, a slope, a shoreline, and the marsh. Wilmer Marsh is managed by the Canadian Wildlife Service to ensure that the area is maintained as a healthy ecosystem for fish, fowl and wildlife. As a wetland habitat it serves as a staging area for waterfowl and provides a habitat to other wetland-dependent wildlife, fish and plant species, including some considered rare, threatened or endangered. For decades the area was used as an unauthorized dumpsite leading to an accumulation of automobile bodies and parts, heating oil tanks, tires, paint cans, building debris, and general household waste.
Environmental assessments of the site revealed that the waste dumping caused soil and sediment contamination from heavy metals, petroleum hydrocarbons, and polycyclic aromatic hydrocarbons. Human health and ecological risk assessments determined that debris removal was necessary to minimize the risks to humans and the natural environment. The removal of contaminated soil and sediment in and adjacent to the marsh was also required. The remediation phase of work presented a challenge due to the sensitive nature of the site and the logistical challenges of removing debris from an area with steep slopes and limited access to the shoreline.
From 2009 to 2011, an extensive remediation program was conducted that included the removal of debris and contaminated soil and sediment. The initial phase of debris removal was completed by workers who rappelled down the bank and removed approximately 111 m3 of debris by hand. Following this, remedial excavation removed approximately 300 m3 of debris and impacted soils from a 50 m section along the marsh. Additionally, approximately 35 m3 of impacted sediment directly adjacent to the shoreline was removed along with approximately 20 m3 of debris and impacted sediment from four previously identified areas within the marsh. Specialized low-impact excavators known as Spyder Hoes were moved into the marsh using an existing trail and remained at the marsh until completion of the restoration work. A helicopter was used to transport materials to and from the shoreline remediation area. Areas were restored using native topsoil from a nearby supply area (outside the wildlife area) to ensure that no non-native species were introduced to the area. Additional debris removal and sediment sampling will be completed in 2011-2012.
Several logistical, health and safety, and technical challenges were realized during the remediation program. The resulting benefits to the natural environment far outweighed the challenges encountered during the remediation program. During the project several lessons were learned by all parties involved. To date the project has been a success due to the collaboration between several government agencies and departments (Environment and Climate Change Canada, Public Services and Procurement Canada,Fisheries and Oceans Canada, and Health Canada), environmental consultants, contractors, and volunteer groups. It is anticipated that the site will be restored to a condition that will be both aesthetically pleasing to people and ecologically healthy for the wildlife that relies on the marsh as a habitat.
FOX-C Ekalugad Fjord Remediation Project
Name and Location: FOX-C Ekalugad Fjord, Baffin Island, Nunavut
Custodian: Indigenous and Northern Affairs Canada (INAC)
The FOX-C Ekalugad Fjord contaminated site is located on the east coast of Baffin Island in Nunavut. The site was originally constructed as an intermediate Distant Early Warning (DEW) Line site in 1957 and abandoned in 1963. The environmental and human health risks found at this site included batteries, asbestos and liquid hydrocarbons, along with unexploded ordnances such as blasting caps and dynamite. The site was also littered with non-hazardous debris such as empty barrels, wood, scrap metal and domestic waste.
The remediation plan developed for the site aimed to mitigate and/or control the migration of contamination to the surrounding environment. Soil with significant contamination or in high environmental risk locations was excavated and treated in a landfarm. This involved thinly spreading the excavated contaminated soils to stimulate biodegradation. Soil with lower levels of contamination was remediated in place. Non-hazardous debris was placed in a newly constructed landfill while all hazardous debris was shipped south for disposal. A detailed health and safety plan was developed prior to the initiation of remediation activities. Safe work practices instituted on the site included having a medic and health and safety officer on-site for the duration of the field season, site orientations for all personnel, and requirements for personal protective equipment to be worn on-site.
In addition to addressing contaminants, the project, funded under the Federal Contaminated Sites Action Plan (FCSAP), increased Inuit employment levels in the area. FOX-C Ekalugad Fiord was completely remediated in 2008, and the site is now undergoing long-term monitoring.
Penhold Transmitter Bunker Remediation Project
Name and Location: Penhold Transmitter Bunker, Alberta
Custodian: Public Services and Procurement Canada (PSPC)
This is a former cold war–era communications bunker site located in farmland in southern Alberta.
During the decommissioning of the bunker in 2001, petroleum hydrocarbon (PHC)–impacted soils were discovered both under the bunker and alongside the structure. Since there is no documentation indicating management of fuel at the military site, it is difficult to determine the time frame and the quantity of fuel released into the environment.
Multiple investigative programs were undertaken to complete delineation and to determine the best option for remediation of the soils. Due to the large amount of overburden materials that were not impacted, the cost of removal of the clean soil to access the contamination was prohibitive. A multiphase extraction system was selected as the best way to remove the PHC product from the groundwater matrix and was installed at the site in 2004. This contract included hydraulic ground fracturing, installation of recovery wells and networks, and the supply and operation of a multi-phase recovery system to treat groundwater.
The system consists of six recovery wells installed six to nine metres below surface, connected to two recovery networks. The recovery wells consist of PVC pipes perforated with sand packs in the active zone. The infiltration gallery for return of treated groundwater consists of a trench excavated and backfilled with pea gravel, located approximately 20 m up-gradient of the plume. Two summer networks were added in April 2006 to enhance the system, and these additional networks vastly improved productivity of removal of product within the groundwater matrix.
The custom multi-phase extraction system consists of a steel container unit divided by a firewall into a small control room and a larger process room. The control room houses the electrical power and control components and the air compressor, and the process room contains the treatment components, including liquid ring pump, vapour-liquid separator, in-line filter, oil-water separators, and carbon vessels for water treatment. The process-room electrical equipment is equipped with explosion-proof components.
Fluid, vapour and air from the recovery wells are drawn into the network pipes and to the system by the liquid ring pump, and into the liquid-vapour separator. The vapour phase is discharged to the atmosphere. The liquid phase, consisting mainly of groundwater with diesel, is pumped to an oil-water separator. Floating product is skimmed off and transferred to two storage containers located in a lined area adjacent to the unit. The groundwater is then polished through two activated carbon vessels, and returned to the ground via the infiltration trench.
Between June 2004 and December 2008, over 4700 litres of diesel fuel were successfully recovered from the groundwater through the system. On-going monitoring of the site has revealed contaminant migration off-site, impacting the neighbouring property. As a result of this movement, soils exceeding Site Specific Target Levels identified through a risk assessment process will need to be excavated and removed from site. This final phase of the project will be tendered and carried out in late 2011.
Oshawa Harbour Remediation Project
Name and Location: Oshawa Harbour, Oshawa, Ontario
Custodian: Transport Canada (TC)
Oshawa Harbour is on the north shore of Lake Ontario, on the eastern edge of the Greater Toronto Area. The Port of Oshawa provides loading, unloading and storage services for cargo ships using the Great Lakes/Saint Lawrence Seaway.
A history of industrial and commercial activities such as the disposal of dredged harbour sediment, waste disposal practices, fuelling operations and shore infilling has resulted in contamination at some of the lands at Oshawa Harbour.
These contaminants include:
- heavy metals which are naturally occurring or from man-made sources;
- inorganic compounds (arsenic, lead, mercury) which are synthetic, not of natural origin and considered hazardous waste;
- petroleum hydrocarbons which are chemical compounds that come from crude oil and petroleum products.
- volatile organic compounds which are found in paints and coatings, cleaning fluids and building materials; and
- polycyclic aromatic hydrocarbons which form when you burn fuel (fossil fuel or biomass).
Transport Canada’s plan to address the contamination, including conducting environmental site assessments, risk assessments and risk management measures, earned an even higher profile when the federal government’s 2009 Economic Action Plan announced funding for this project was received through the Federal Contaminated Sites Action Plan. The project helped stimulate the local economy and provided employment opportunities to industry and local businesses.
Upon considering the historical and continued industrial use of the property, and after completing risk assessments to identify risks posed by contaminants to human health and ecological receptors, it was determined that carefully selected risk management measures would be the most cost effective and best way to address the risks from land based contaminants.
Risk management measures included:
- installation of liners and capping with clean soil, gravel or asphalt depending on the site use;
- installation of a phytohydraulic barrier (deep-rooted hybrid poplar trees);
- installation of fencing to control site access; and
- implementation of erosion and storm water control measures.
Cleaning up contaminated sites is not always the optimal remedial approach to address contamination. A risk-management approach is an effective strategy that not only addresses risks posed by the contamination but is also a technically and financially viable remedial option.
By addressing the contamination through risk management measures, Transport Canada has addressed risks to human health and environment, at reasonable costs, while transforming the contaminated sites into attractive areas suitable for sustainable reuse.
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