Abstracts

Geological and geochemical conditions commonly found in Canada that should be considered
when implementing a bioremediation approach include: low groundwater temperatures,
low permeability matrices and fractured rock. Recent experience implementing
bioremediation remedies under these conditions have provided insights and lessons
learned for optimizing bioremediation of chlorinated solvents in Canada.
Groundwater temperatures defined as cold (i.e., below 10 º C) are commonly found north
of 45 degrees latitude. Understanding the feasibility of bioremediation of chlorinated solvents
and the practical limits of bioremediation under cold conditions is important in
remedy selection and expectation management for high latitude bioremediation projects.
Examples of successful bioremediation at sites in Alaska, Denmark and Canada, will be
presented with a focus on degradation half-lives, concentrations of dechlorinating bacteria
(Dehalococcoides [Dhc]) and remediation outcomes.
Low permeability strata are common in some of the most highly industrialized areas of
Canada; notably in Southern Ontario and Quebec. Originally conceived as an oil and
gas extraction technology, hydraulic fracturing can also be used to improve distribution of
bioremediation amendments thereby improving bioremediation outcomes. Examples of
successful implementation of hydraulic fracturing and other approaches for bioremediation
in clay strata and fractured rock environments will be discussed. One such site, in the
Toronto area, with groundwater concentrations of PCE, TCE and cis-1,2-dichloroethene
(cDCE) above regulatory limits will be presented. A high pressure grout pump was used
to inject EHCTM electron donor and KB-1 ® . After KB-1 ® application, a 10,000-fold
increase in Dhc abundance was observed from pre to post bioaugmentation in less than
one year. cDCE concentrations declined concurrently to below detection limits, reaching
Ontario regulatory standards (Table 3) and site remedial objectives in the target monitoring
wells for all chlorinated compounds within 1.5 years of bioaugmentation.
Groundwater Aspects of Deep Geological
Repositories
Wednesday, October 28, 10:10 – 11:50
Chair: Mark Jensen
Room: Heritage
228 - Deep Geologic Repositories: Developing a Geoscientific
Basis for Long-Term Safety
M.R. Jensen & M. Hobbs
Nuclear Waste Management Organization, Toronto, Ontario, Canada
The Nuclear Waste Management Organization (NWMO) is responsible for implementing
the Adaptive Phased Management (APM) Program, Canada’s approach for the longterm
management of its nuclear used fuel. The APM program, approved by the federal
government in June 2007, envisions that nuclear used fuel would be placed within a
46 IAH-CNC 2015 WATERLOO CONFERENCE