I have concerns about Aecon…

I have concerns about Aecon filling in 571 hectares, part of which is below water pit and an existing pond.
What evidence is there to prove this action will not cause disruption to private wells in the area, as well as green lake and the credit river.
Is there an environmental analysis being done to identify issues or concerns.
What types of materials are being used to fill and will this be monitored.