Imperial Oil Limited - Permit to take water

Comments received from the City of Hamilton as follows:

1. We would like more information on the nature of Imperial Oil’s construction activities, as well as the rationale to for the Permit given the depths of excavation and local groundwater levels. If a technical report in support of the application is available, please forward for our review and record.


2. The PTTW area intersects Environmentally Sensitive Areas, Highly Vulnerable Aquifers, watercourses, and Significant Groundwater Recharge Areas as delineated from Source Protection Assessment reports. Thorough discussion of the potential impacts of these areas within their report should be addressed, along with comprehensive mitigation strategies in case impacts arise.


3. Migration of pipeline contents (e.g. BTEX/VOCs, PHC F1-F4 or other compounds) has the potential to allow for migration in overburden sediments, especially in areas where coarse textured sands and gravels are the predominant overburden soil type. These activities can release acute risk contaminants in surface water and groundwater resources. We request that these impacts be thoroughly discussed in the PTTW application report, along with comprehensive mitigation strategies where redundancies are built into the design.


4. We assume that the proponent has performed a cone of influence calculation based on maximum drawdown required and local geology to safely perform construction/maintenance activities. We recommend that all private well users within 500 m of dewatering are notified of these activities and for the estimated radius of influence to be treated as a minimum distance to conduct monitoring of water level and water quality on private well users before, during, and after commissioning. Private well users within close proximity of the pipeline area should have water quality testing conducted to confirm that high risk organic contaminants do not enter private supplies.

Ministry's consideration:

1. The technical report was provided to the City of Hamilton for their review.


2. This is a non-consumptive taking meaning there is no actual removal from the overburden unit and the groundwater pumped during dewatering will be discharged back into the shallow overburden via natural infiltration, so adverse impact on the groundwater recharge areas or environmentally sensitive areas is not anticipated. There is no municipal well located within 5 km of the pipeline ROW.


3. . First of all, this project is about installation of a new pipeline, so release of petroleum contents is not an issue and secondly, the proposed environmental mitigation plan includes measures to deal with the contaminated soils in case of petroleum contents release from an existing pipeline. In our opinion, the proposed environmental mitigation plan is reasonable which is recommended to be made a condition of permit approval.


4. An undertaking of a door to door survey within the estimated zone of influence or 250 m of ROW is already recommended to be included in the permit. The proposed mitigation plan includes sampling of selected private wells, subject to owner’s access approval, in order to establish baseline water quality. Inclusion of environmental mitigation plan as a condition of approval will address this concern.

In summary, the City’s concerns have already been addressed in the review comments and hence, changes in the technical review are not needed.