Cumberland Aggregate Mine

Project Overview

Segale Properties has submitted an application to King County for approval of an aggregate mine near the town of Cumberland in southeast King County. When operational, the project will supply King and Pierce Counties with aggregate materials for public road and transit projects, housing, and commercial businesses throughout the region, while generating local economic benefits, jobs, and tax revenue for southeast King County. The site will help the region maintain an adequate local supply of aggregate material and support the obligations of the state’s Growth Management Act.

The Cumberland property was originally acquired by Segale in 2003 after an exhaustive multi-county search for potential sites of suitable size and location. The proposed site is approximately 990-acres and is partially forested and will be mined in stages over time. The mine site is expected to provide aggregate, sand, and rock materials to the region for 25-35 years. Operation of the mine will be overseen by the Washington State Department of Ecology (DOE), Department of Natural Resources (DNR), and King County under strict rules to protect the environment and surrounding area.

For 40 years, Segale has owned and managed a 664-acre aggregate mine in Auburn, Washington known as the Auburn Pit. The Cumberland Aggregate Mine will serve the region as a necessary replacement for the Auburn Pit when its resources are exhausted in the next 3 to 5 years.

Key Facts:

• The Cumberland project site is approximately 990-acres.
• Mining operations will not occur all at once across the site and instead will be mined in smaller 50+ acre sections over time.
• All mining activity will be at least a 1/4-mile from surrounding residences.
• Wide forested buffers will be maintained around the site.
• Mining operations will be excavated down into the site to minimize noise impacts.
• Groundwater supply and water quality will not be negatively impacted by the project.
• No stormwater or runoff of any kind will leave the site.
• Truck traffic will intentionally avoid peak hour traffic and will be distributed to the region along main arterial roadways.
• The site will go through reclamation after mining activity is complete and will be returned to forest land.

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Who We Are

Segale Properties is a fourth-generation, family-owned, commercial real estate development and property management company. We own and operate a mix of commercial, industrial, residential, agricultural, and natural resources properties throughout Washington State.

We have been in the aggregate business for over 60 years with active operations in King, Grant, Cowlitz, and Thurston Counties. We have a reputation for being responsible and conscientious landowners/managers, we prioritize job creation, sustainable practices, and contributing to the economic and social fabric of our region. Our commitment to longevity extends to our relationships, products, and community partnerships. We are dedicated to fostering partnerships and uplifting the communities we serve, ensuring a lasting and positive economic legacy for future generations.

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