Costly cleanup measures must continue at courthouse as new plan is developed
By Joel Wittnebel/The Oshawa Express
The City of Oshawa must continue with expensive clean-up efforts at the Durham Regional Courthouse, despite their ineffectiveness, as a new plan is developed to deal with the contamination that exists beneath the building.
A previous report from the City of Oshawa, delivered to council in December of 2016, noted that oxidant injections, a preventative effort to mitigate the contamination of trichloroethylene (TCE) were having “no success” at eliminating the elevated levels of the chemical and that even with continued injections they “do not and will not address the exceedances on certain parts of the perimeter of the site.”
Now, the province is ordering the city to continue with the injections, even as the city works to develop a new remediation plan for dealing with the courthouse lands.
“I reasonably believe that the requirements specified in this order are necessary or advisable so as to prevent, decrease, or eliminate an adverse effect that may result from the presence or discharge of contaminants…in, on or under the property,” states Andrea Brown, from the Ministry of the Environment and Climate Change (MOECC) in her report to the city.
The Durham Regional Courthouse, a brownfield project constructed between 2007 and 2009, had a series of safety measures put in place to contain the contamination on the site, which mainly consisted of elevated levels of (TCE) a chemical used most commonly for cleaning grease from when General Motors operated on the site.
As part of a lease signed with Infrastructure Ontario (IO) in 2005 for the next 99 years, the city, the owner of the site, is responsible for the environmental monitoring. At that time, IO demanded the city use what the industry calls a full depth generic approach. This general standard for cleaning contamination is typically more onerous than a specific approach which can identify the particular areas of focus.
As part of that approach, a Waterloo barrier is installed underground around the perimeter of the courthouse to contain any leaking groundwater and sending it to a treatment facility located on the property. The monitoring also includes a series of wells for testing the groundwater. It’s here that continued elevated levels of TCE have been seen year after year.
To treat this, the city has been paying for costly oxidant injections into the ground, running in the neighbourhood of $100,000 annually. This makes up nearly half of the cost for the monitoring on a yearly basis with the total reaching between $200,000 and $230,000.
In fact, the highest levels of contamination seen to date, were found in March of this year. These elevated levels have led the province to find that perhaps incorrect information was gathered when the record of site condition (RSC) was approved and area greenlit for development back in 2007.
“I am of the opinions the RSC contained inaccurate certification regarding the completion of the remediation work and conditions at the site,” Brown states.
Now, the province has ordered the creation of a revised remedial action plan to include specific methods to deal with the contamination.
The city has tasked Golder Associates with preparing the plan. Golder has been responsible for the monitoring on the site on behalf of the city.
However, it won’t come cheap, as Golder has cited a $90,600 price tag for the risk assessment with an unknown number of additional costs. A previous letter stated that it could be as much as $150,000.
Those costs could eventually be realized in the savings, which Golder estimates between $850,000 and $1.2 million in the first 10 years of the new approach.