City hears options and cost estimates for cleanup at 1300 Cleveland Ave.; DNR requires remedial action

GEI Consultants presented an update to the Wausau Common Council on Jan. 13 about the environmental regulatory case for the former Wausau Incubator property at 1300 Cleveland Avenue. A GEI consultant told the council that "the DNR confirmed that the site investigation is complete as of July 2025 and that remedial action will be necessary for case closure." GEI said prior Phase 2 work and subsequent groundwater monitoring for PFAS led the DNR to conclude the investigation was complete and that soil remedial measures are the likely path to closure.

GEI outlined four preliminary remedial approaches the city could pursue. A cap‑based approach with limited excavation would remove an estimated 3,800–6,000 cubic yards of soil and carry an opinion of probable cost of about $500,000–$850,000 (inclusive of disposal and GEI oversight). A full excavation to remove the direct‑contact exposure pathway to 4 feet was estimated at 12,000–16,000 cubic yards with an opinion of cost of about $1.4M–$2.0M. A hybrid cap with targeted deeper excavations was presented with an opportunity to remove deeper industrial exceedances (presented in the slides as "5385 hundred cubic yards" in the transcript) and an opinion of cost of roughly $750,000–$1.1M. A most‑extensive excavation option would remove soils to variable depths (up to and beyond 8 feet in isolated locations) to meet nonindustrial standards in more locations and carry the highest cost range.

GEI emphasized that the cost estimates are presented as a 90% confidence interval and depend on final excavation geometry, waste classification at disposal, and DNR approval of the remedial strategy. Council members questioned whether excavated soils would be treated as hazardous waste; Kevin Fable, an environmental engineer on the GEI team, said current data indicate the anticipated excavated materials would be classified as solid waste rather than hazardous waste and therefore could be disposed of at solid‑waste facilities that accept that material. GEI staff also said that retaining or relying on the existing concrete slab as part of an engineered cap is possible but would require maintenance and possibly future DNR approval if removed at redevelopment.

Next steps described by GEI included identifying and evaluating remedial alternatives, preparing a remedial action report for DNR review, pursuing available federal or state funding if appropriate, implementing the selected remedial option, and submitting a remedial action completion report to the DNR followed by a case closure request. The presenters cautioned that none of the options would likely yield an unrestricted closure; selected remedies would leave residual impacts that would have to be managed during future redevelopment.