Development of a large quarry for extraction and crushing of dolostone for aggregate has been proposed in Ontario, approximately 125 km northwest of Toronto. This will be the largest quarry ever developed in Ontario. Upon completion, the proposed quarry will have a depth of approximately 70 m, an area of 937.1 ha (9 km2) and will be dewatering up to 600,000 cubic metres per day of groundwater. As a first step towards approval, Highland Companies has submitted an application under the Aggregate Resources Act (ARA).
Although NVCA has in-house professional technical resources, from time to time the scale or technical specificity of an application requires them to obtain additional professional technical services to provide assistance. The recently submitted 3,100 page application by the Highland Companies represents such an application. The proposed quarry is almost entirely located in the headwaters of the Pine Rive amongst Karst topography. Given its position in the landscape, its areal extent and considerable depth of extraction and volume of dewatering, the proposed quarry has the potential to impact both the natural heritage features and surface and ground water resources of the quarry lands and surrounding areas.
SLR Consulting (Canada) Ltd. has been retained by the Nottawasaga Valley Conservation Authority (NVCA) to assist in the application review. NVCA is a local regulatory and review agency responsible for floodplain and erosion protection, natural features and groundwater in local watersheds.
SLR’s role is to provide a scientifically sound and defensible review of the application. The key to this review is to determine if the science presented in the application’s supporting documentation is correct, applicable and comprehensive enough to support the findings and conclusions presented.
A hallmark attribute of our team is its recognition and consideration of groundwater and surface water interactions as they influence ecological function. All senior members of the SLR team have forged a cross-discipline understanding and appreciation of the importance of this boundary interface. We have successfully completed numerous projects where a detailed understanding of the groundwater regime and groundwater dependant receptors and functions at surface were used to predict potential impacts and develop adaptive management plans. This understanding, together with the inclusion of the Karst expertise from SLR in the UK and a ground water modeling team from Ontario in Canada, factored strongly in the decision to award this assignment to SLR.