Question 5 of 8: Environmental Impact of Hydraulic Fracturing near Chatham, Ontario

Question A-5: Environmental Impact of Hydraulic Fracturing near Chatham, Ontario (20 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

Southwestern Ontario around Chatham-Kent is flat, intensively farmed land underlain by Devonian shale/carbonate bedrock and a shallow, agriculturally-important groundwater system, with the region already hosting legacy conventional oil and gas wells dating to the 19th century — several of the environmental concerns below are sharpened by that specific local context rather than being generic.

Groundwater quality. The principal risk pathway is not the fracturing zone itself (typically >1 km below the shallow aquifers used for agricultural and domestic wells) but poor well-casing integrity allowing fracturing fluid, formation brine, or stray methane to migrate up the annulus into shallow aquifers — a risk made worse in this specific area by the density of pre-existing, sometimes poorly-documented legacy wells that can act as unintended vertical conduits between formations. Any regulatory approval should require full well-integrity certification and mandatory baseline (pre-drilling) testing of all water wells within a defined radius, so a later dispute over causation has a factual baseline.

Water use and management. Fracturing consumes very large volumes of water per well (millions of litres), competing with agricultural irrigation demand in a farming-intensive region; the resulting flowback/produced water is high in TDS, chlorides, and naturally occurring radioactive material (NORM) mobilized from the formation, and must be managed via deep injection disposal, treatment, or trucking to an approved facility — all of which carry their own transport, spill, and (for injection) induced-seismicity risk.

Induced seismicity. Disposal of produced water by deep injection, and less commonly the fracturing process itself, has been associated with induced seismic events elsewhere; while southwestern Ontario is not a historically high-seismicity zone, any injection-well component of the operation should be subject to a traffic-light seismic monitoring protocol.

Air emissions and land use. Fugitive methane emissions (a potent greenhouse gas) from wellheads, compressors, and flowback handling; VOC emissions from condensate tanks; increased heavy-truck traffic on rural roads for water/proppant/waste haulage; and well-pad/access-road land disturbance and habitat fragmentation across what is currently productive farmland, with corresponding loss of agricultural capacity for the pad footprint and buffer.

Regulatory framework. In Ontario, hydraulic fracturing for oil and gas is regulated primarily under the Oil, Gas and Salt Resources Act and its regulations (well construction/integrity standards, Ministry of Natural Resources and Forestry oversight), with an Environmental Assessment potentially triggered under the provincial Environmental Assessment Act for larger projects, alongside Ontario Water Resources Act permitting for water taking and Clean Water Act source-protection considerations given the region’s reliance on groundwater for both agriculture and drinking water.