Abstracts

116 - The Effect of Injection Methods on the Distribution of
Remedial Compounds
Rick McGregor
InSitu Remediation Services Ltd, St. George, Ontario, Canada
The application of in situ methods for treating contaminants within groundwater and soil
has increased over the past decade. The understanding of how contaminants are remediated
using a variety of compounds is fairly well understood and demonstrated. However,
numerous studies/project using in situ remediation have resulted in incomplete realization
of the remedial objectives. In order for in situ methods to be effective, the injected compounds
must interact directly or indirectly with the contaminant. Site specific factors such
as geology, hydrogeology, geochemistry, contaminant distribution, etc. play an important
role in controlling the design of any in situ program, as does understanding the role of
advection and diffusion in the delivery and transport of the compounds to the contaminant.
Unfortunately very few studies have been completed in the field to look at the actual
distribution of compounds.
A field study was conducted in an unconsolidated, unconfined aquifer to evaluate various
injection and delivery methods for a variety of oxidants and reductants including persulfate,
percarbonate, hydrogen peroxide and emulsified vegetable oil. Delivery methods examined
for each oxidant included injection through vertical wells, injection by direct push technology
using drop point and side tool technologies. The results of the study indicated that the
delivery method has a significant impact on the distribution of the compound within the
subsurface whereas the type of compound also impacted the distribution geometry within
the aquifer tested. Direct push technology offered superior distribution compared to injection
of the compounds into vertical wells with injection through side tools showing better
vertical and lateral distribution than drop point methodology. These results suggest that
the choice of delivery method is a key design parameter for any in situ remedial program
and that the delivery method needs to be customized based on site-specific factors to the
choice of remedial compound being used.
249 - Enhanced in situ Bioremediation of Chlorinated Solvents in
Canada
Jeff Roberts, Phil Dennis, Sandra Dworatzek & Peter Dollar
SiREM, Guelph, Ontario, Canada
Bioremediation of chlorinated solvents, including perchloroethene (PCE) and trichloroethene
(TCE), in groundwater is a proven and cost effective remedial approach. KB-1 ® , a
bioaugmentation culture that promotes the complete dechlorination of chlorinated ethenes
to ethene has been used extensively for bioremediation projects around the world. KB-
1® is the only anaerobic bioaugmentation culture to receive Federal regulatory acceptance
through the New Substance Notification (NSN) regulation process and was added to the
Domestic Substances List in 2008. Since then KB-1 ® has been applied successfully at
several sites in Canada.
IAH-CNC 2015 WATERLOO CONFERENCE
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