Updated Through August 11, 2026

Project Name: Grading Permit GRDE23-0083

Proposal: The King County Department of Local Services, Permitting Division (KC DLS-P) issued a Determination of Significant (DS) and Request for Comments on Scope of Environmental Impact Statement (EIS) regarding the proposed Cumberland Aggregate Mine and Asphalt Facility near Cumberland above the Green River Gorge on July 8, 2026.  The applicant, Segale Properties LLC, envisions a 990-ac footprint consolidating 15 parcels into a massive extraction and processing zone.  Scheduled to operate over a 35-yr lifespan in four sequential phases, the mine is engineered to extract and process up to 55 million cu yds of aggregate material—over 1.5 million cu yds per year.  

Location:  The site borders the Kanaskat-Palmer State Park and the deeply incised Green River Gorge, introducing profound spatial conflicts between heavy industrial activity, pristine recreational areas, and critical aquatic habitats.

Parcels:  The applicant purchased all its parcels that are part of the proposed project from Plum Creek Timber Company, Inc.  Those parcels are: 1521079007, 1521079008, 1521079009, 1521079020, 1721079001, 2121079001, 2121079005, 2121079006, 2121079008, 2121079009, 2121079015, 2121079016, 2121079029, and 2121079030.  All the parcels are within the Forest (F) zone.

The GMVUAC led a team to develop detailed Comments on the subject proposal and submitted same to KC DLS-P on August 7, 2026–Defend Cumberland, Enumclaw Plateau Community Association (EPCA), Greater Maple Valley Unincorporated Area Council (GMVUAC), Green River Coalition (GRC), Green Valley/Lake Holm Association (GV/LHA), and Soos Creek Area Response (SCAR)—all of which are are members of the Joint Team of King County Rural and Urban Unincorporated Area Organizations, and cover a large portion of southeast King County.

The team conducted in-depth reviews of all the available State Environmental Policy Act (SEPA)-related documents provided by the applicant to the KC DLS-P.  The team’s detailed Comments address every item listed in the subject DS and Request for Comments on Scope of the EIS, as well as some additional ones.

Based on the team’s research, which formed the basis for the detailed Comments, it concluded the proposed project would cause adverse local, regional, and downstream impacts on the Green River and its environs that would have wider impacts on cultural resources and threatened and endangered runs of salmon, as well as degrading overall water and air quality in the region and deleteriously impacting the pristine and scenic Green River Gorge corridor.  The team also concluded the proposed project will lead to some long-term changes that most likely are irreversible from both ecological and environmental health standpoints.

Given the vast variety and severity of the issues, including many critical items that cannot be feasibly mitigated or mitigated to sufficient extent to assure Public and environmental health, the team recommended the “No Action Alternative.”