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Environmental Geology and Hydrogeology
Keltic Petrochemicals Inc.
Keltic Petrochemicals Inc. hired earth-water Concepts inc. as part of a scientific team to conduct the surface water hydrology, geology and hydrogeology components of environmental impact assessments for: 1) a proposed petrochemical plant, co-generation electrical power plant, and LNG receiving terminal at the community of Goldboro on the eastern shore of Nova Scotia; and 2) a 58 km long stretch of new 100-series-type highway proposed to extend from east of the plant site, across the province to the Trans-Canada highway at Antigonish on Nova Scotia's north shore.
The proposed petrochemical plant site is located at a former
gold district and contains several dozen mine shafts,
extensive underground workings, and
four former gold mill (mercury amalgam) tailings disposal ponds. The
~300 hectare site is underlain by a thin layer of glacial till and
low-permeability metasediments that are significantly folded
and faulted. Fault zone fracture flow
and old unmapped mine workings, some
known to be in direct
hydraulic contact with the ocean, have the potential to
produce complex groundwater flows at the site. The plant also
needs a 20.3 million US gpd water supply (see here)
that requires raising a lake level and flooding an area about twice the
size of the lake. The proposed highway route traverses an
entire geologic cross-section of the province, and crosses 38
streams in 21 secondary watersheds located in 5 primary
surface watersheds.
Working closely with the terrestrial biologists on the science team, earth-water Concepts inc. undertook comprehensive investigations that included:
- in-depth library reviews of old mining reports to locate mine workings, underground maps and former tailings disposal areas at the proposed plant site,
- field mapping of the plant site geology, extensive soil, stream water and stream sediment sampling to assess past mining legacies and serve as a new baseline,
- installation, hydraulic testing and groundwater sampling at several piezometer nests located on and off the proposed plan site,
- a detailed well survey and water quality sampling program that incorporated all wells within the community of Goldboro and beyond,
- assessment of potential groundwater, surface-water and ecosystem interactions related to land form changes necessary for plant-site construction,
- assessment of predicted global climate changes and possible tsunami on the long-term viability of the proposed site and sustainability of the petrochemical and LNG project,
- general surveys of several hundred water supply wells within a 1 km buffer zone along the entire proposed highway alignment,
- geological map and exploration assessment file review for base metal interests along the entire proposed highway alignment to identify areas with potential acid generating rock,
- road and helicopter visits to evaluate all
proposed road-stream crossings, and preliminary numerical
assessments of annual and seasonal stream flows at all
crossings.
Trans-Canada Highway Twinning
While
employed at
Public Works and Government Services Canada, the principal at
earth-water Concepts inc. was assigned to carry out the
geology and
hydrogeology components of an environmental assessment along
approximately 60 km of existing road for the twinning of
Highway 104 from Oxford to Kemptown, Nova Scotia. This
provincial-federal construction project required a significant widening
of the existing highway right-of-way, and land surface grading
changes
that
could potentially impact streams and water supply wells due to changes
in water levels during construction and
the application of additional road salt during winter
highway operation. Working closely with associate
biologists, a comprehensive investigation was carried out that included:
- desktop and field mapping of the soil and bedrock geology along the entire section of highway under assessment,
- review of mineral exploration assessment files for base metal interests along the entire route to identify areas with potential acid generating rock,
- surveys of all water supply wells located within anticipated zones of influence,
- evaluation of all stream crossings to identify and assess the potential for new impacts due to surface flow changes,
- evaluation of possible groundwater sensitive ecosystems and possible impacts to them due to construction and operational changes along the subject stretch of highway.
Imperial Oil Divestitures
Following the purchase of a number of former
McColl-Frontenac (Texaco) bulk fuel distribution and service station
properties in Atlantic Canada, Imperial Oil Canada was ordered by the
Federal Government under terms of the Competition Act to
divest of a number of the newly acquired sites. While it had
purchased the sites as-is, there were concerns of pursuing
liability during the resale of properties, and Imperial
Oil embarked upon a broad environmental assessment and
cleanup program for all sites.
While employed by others, the principal at earth-water Concepts inc. staff directly managed and carried out the geology, geochemistry, and hydrogeology components of the investigations and remediation design of over two dozen petroleum sites. All sites were worked on simultaneously and on a very tight schedule to meet property resale conditions. The work, where individual projects were valued at over $1 million at some sites, included the development and implementation of unique and innovative site investigative and cleanup techniques that were borrowed from past experience while doing petroleum resources exploration work. All of the assessment and remediation work was completed on time and below budget.
Advise to Insurance Companies
The
predecessor company to earth-water Concepts inc. was called
upon regularly by a number of insurance company clients to help
in subsurface assessments for the cleanup of residential
and other heating oil and gasoline spills. Typical projects, with
assessment and
cleanup costs ranging from several tens to several hundred
thousand dollars, usually involved multiple properties on which
there had been multiple spills over time. The
earth-water Concepts inc. staff members were called
upon to evaluate site water and soil samples and analyze
laboratory data for
proper petroleum product fingerprinting in efforts to
differentiate various spill events and spill ownership. This data was
used by client
firms to seek proper subrogation where other insurance firms
were involved.