DNR approves Constantine permit
July 18, 2019
A wastewater permit and reclamation plan for the Constantine exploration project was issued Wednesday by the state Department of Natural Resources and Department of Environmental Conservation.
The permits will regulate how liquid and solid waste will be managed at the Palmer Project’s exploration site 35 miles upstream from Haines on a tributary of the Chilkat River.
Constantine plans to blast a one-mile tunnel into the mountainside for more extensive and year-round drilling access.
The 16-foot diameter tunnel will create 70,000 cubic meters of waste rock, Constantine’s spokesperson Liz Cornejo said. The groundwater that drains from the tunnel will be diverted into two settling ponds. After sediment settles from the water, the wastewater will be released back into the ground through perforated pipes.
Along with permit approvals, state agencies published 31 public comments submitted to DNR responding to issues they said were within their regulatory authority.
The state received a total of 218 comments, “the majority of which were general comments that did not concern permit-specific requirements,” according to the agency’s comment response document.
Comments that resulted in changes to the permits dealt with: requesting Constantine provide additional baseline groundwater data, ensuring that the trial period for groundwater monitoring take place when there is no snow, include requirements for visual inspection in the spring, maintaining settling ponds and limiting one of the perforated pipes to a lesser discharge volume.
“Stipulations should be added to monitor the depth of settled solids and triggers on when to initiate solids removal. Typically, storm water best management practices require the removal of settled solids when they reach one-third pond volume,” one commenter wrote about the settling ponds.
In response, agencies added that the settling pond and pipe system “shall be properly operated and maintained.”
Permitting agencies also adopted a commenter’s suggestion that “visual monitoring should include signs of sheen on the water at the ponds, groundwater and surface water samples, and actions to report such observations.”
Core comments concerned community members have repeatedly expressed about avalanche danger in the proposed area, pipe freeze in winter, and discharge water entering nearby streams did not result in any permit modifications.
The agency responded, “The Waste Management Permit does not account for acts of nature such as avalanches,” that system piping and diffusers will be installed at a minimum of 6.6 feet in the ground “well below frost line,” and that “Land Application discharge shall not form a connection with waters of the U.S.”
Underground excavation won’t begin until 2020, Cornejo said. The wastewater permit will expire July 16, 2024.
People who disagree with the permit have 20 days to request a review with the Director of the Division of Water at the Department of Environmental Conservation.