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In an updated permit application submitted last week to the state, Constantine Metal Resources made significant changes to its wastewater management plan as it prepares for underground mineral exploration at the Palmer Project.

Constantine’s revision includes changing the location of its wastewater disposal system, adding a water treatment plant and repurposing settling ponds. The state, which originally issued the permit in 2019 but then remanded it for further review, said there will be no public comment period for Constantine’s updated plan.

The company’s revised application incorporates long-awaited results of dye tracer studies, completed in two phases over the last three years, that show some, but limited, connection between ground and surface water in part of the Glacier Creek watershed.

According to the studies, there was connectivity where Constantine originally planned to discharge wastewater. The company’s waste management permit says “land-application discharge shall not form a connection with waters of the U.S.”

Constantine now plans to discharge wastewater in a different location, where the dye study suggests there is no connectivity.

In September 2019, the Alaska Department of Environmental Conservation remanded Constantine’s permit following complaints from Haines residents and environmental groups about the thoroughness of the company’s application and its assessment of the area’s hydrology.

Among several concerns, environmental groups argued that Constantine should have applied for an Alaska Pollutant Environmental Discharge Permit (APDES), not just a waste management permit. The former regulates pollutant discharge to surface waters, per federal law, while the latter is a state permit strictly for land or subsurface disposal.

The U.S. Supreme Court ruled in the spring of 2020 that discharging pollutants into the ground requires federal approval under the Clean Water Act if it could be considered (by connection to surface water) the “functional equivalent” of disposal directly into surface waters.

In August 2020, Constantine withdrew its original wastewater management system design until completion of further site investigations and groundwater studies.

In its updated application, Constantine said it would change the location, spacing and length of its wastewater disposal diffuser, a system of perforated pipes buried six feet below the surface, “to mitigate potential surface discharge and optimize groundwater flow paths in the overburden, based on recent site investigation results.”

Dye introduced underground where Constantine planned to discharge wastewater in its 2019 permit application was detected at a sampling site in Glacier Creek during phase one of the study, between December 2019 and May 2020. No dye introduced at the newly proposed discharge location was detected in surface water during phase two of the study, which ended in August 2021.

“The location of the proposed 2022 Lower Diffuser is an improvement over the 2019 location as the dye tracing indicates that it does not impact Glacier Creek and its tributaries in the time interval tested,” scientists from Ozark Underground Laboratory (OUL) concluded in a report submitted to the state with Constantine’s revised application. OUL is a Missouri-based groundwater consulting firm that Constantine contracted to do the study.

In its 2019 Land Application Disposal (LAD) system design, Constantine said it would pipe wastewater from its underground exploration tunnel to two settling ponds, then discharge the water into the environment through two diffusers—an upper and lower one.

In its revised design, Constantine changed the location of the lower diffuser, eliminated the upper diffuser and said it would install an active wastewater treatment plant instead of two passive settling ponds.

The company plans to repurpose those ponds. One will be used for temporary wastewater storage in case of overflow or when the treatment plant isn’t operating, whether for maintenance or malfunction. The other pond will store solids filtered out of wastewater during treatment.

The wastewater consists of seepage that could have excessive levels of heavy metals, such as manganese and vanadium, according to estimates by pHase Geochemistry, a firm contracted by Constantine to study the area’s groundwater chemistry. The seepage also could become contaminated with nitrates used for blasting.

Still, Constantine’s application notes, “There is no pre-existing wastewater to sample to establish the exact chemical composition of the proposed wastewater discharge.” The permit requires ground and surface water monitoring.

Treatment will consist of regulating pH and injecting coagulants and flocculants to filter out particles.

Constantine also in its new plans slightly increased its expected cost of reclamation for permanent closure of the Palmer site to $1,073,970 from $1,011,542 in 2019. The company projects that would be enough to pay for a hydraulic plug to block the underground portal as well as site visits and maintenance twice a month for three years.

Constantine did not change its 2019 assessment that it would be unlikely to encounter potentially acid-generating (PAG) rock during underground exploration. PAG rock is heavy in sulfides and harms ecosystems when not properly managed.

Based on rock samples taken over several years, Constantine predicts that none of the 170,000 metric tons of waste rock yielded by exploration will be potentially acid-generating.

As in its 2019 application, the company’s 2022 plan includes, as a contingency “in the very unlikely situation” that it finds PAG rock, a lined pad to store the rock before hauling it back underground for permanent disposal.

Constantine’s updated application says it plans to build the revised wastewater discharge system this year and to begin construction of the underground ramp in June 2023.

DEC said there would be no public comment period during the department’s review of Constantine’s revised submission. There is not a public timeline for the review either.

“Engineering plan approvals are conducted between professional engineers licensed by the State of Alaska and are not subject to public notice consistent with 18 AAC 72,” DEC’s Wastewater Discharge Authorization Program manager Gene McCabe said in an email to the CVN.

Takshanuk Watershed Council executive director Derek Poinsette said he thinks the public should have the same opportunity to provide input as it did in 2019. “Constantine’s new waste management permit application is a significant departure from the design submitted in the 2019 application. DEC should not consider this a simple amendment to an existing permit and deny any public review process. In 2019, it was the public, not DEC, that insisted Constantine do better.”

A week ago Constantine announced its biggest annual Palmer Project budget to date: $18 million, some of which will be used to build a camp this summer for 50 to 60 employees, in addition to the wastewater management system.

Japan-based DOWA Metals and Mining Co., which owns 55% of the Palmer Project, committed to funding the entire 2022 program, but Constantine can elect to contribute before the end of the calendar year, according to a company press release.

Constantine lost its majority interest share of the project last year when DOWA began funding more than half of the project’s expenses.