A town consultant says subsurface disposal is not a viable solution for the treatment of wastewater in Erin or Hillsburgh.
Gary Scott of Ainley and Associates Limited presented a technical memorandum examining subsurface alternatives to Erin council on May 16.
Large subsurface sewage disposal systems, similar to a septic system, are typically used for smaller developments. A system is in place at Island Lake subdivision in the Town of Mono as well as at Centre 2000 in Erin.
The $31,500 investigation into the alternative disposal system was authorized by council in January after it was suggested by Transition Erin at a public liaison committee meeting.
Scott said based on Ministry of Environment and Climate Change guidelines, servicing the existing Hillsburgh community using subsurface disposal would require 4.9 hectares of land and 19.5 hectares for a full build out. In Erin, 19 hectares are required for the existing community and 38.5 hectares for full build out.
Scott said the ministry would likely request a spare bed capacity, which would double the land required.
“These are much larger than anywhere else you can really find in Ontario,” he said.
His report examined the regulations, land availability, topography and cost.
Based on the criteria, Scott said using subsurface disposal is not viable.
“For Hillsburgh, obviously there is an opportunity to offset the cost of transmitting the water down through Erin, and there is land available so we designated Hillsburgh as potentially viable for these solutions,” said Scott
However, through further investigation of three subsurface alternatives for the community, he said it would offer no advantage over the preferred surface water discharge alternative of the Servicing and Settlement Master Plan.
Scott said subsurface disposal alternatives for Hillsburgh could cost between $34.8 and $37.3 million for treatment only.
“We should not proceed further … with subsurface but go back to the surface water alternative,” said Scott.
Councillor Jeff Duncan said, “I think that was the conclusion probably a lot of people through we would get to, but I think it was very important that we spend the money, that we went through this exercise to hash this out and get to some of the results.”
Council accepted the report for information.
Second report to cost $8,000
At the May 2 meeting, council asked Ainley to provide a report on the feasibility of two treatment plants – in Hillsburgh and Erin village – and seek agency comments.
The current option being considered is a treatment plant south of Erin village, connected to Hillsburgh by sewer force main.
“I totally respect our engineers and council for their opinion, but I think it’s something that can’t be ignored because we’re making a decision for the long-term of the Town of Erin,” council Matt Sammut had said.
At the May 16 meeting, staff told council the report will cost an extra $8,000.
“It is underway now, and I do believe since the question was raised that we do need to do something because I don’t want to see this whole thing finish and then a part two (order) come up,” said Mayor Allan Alls.
A part two order, which anyone can request, can be filed when outstanding issues have not been addressed in the EA process. It can potentially increase the level of assessment.
Council approved the extra funding with no discussion.
