I live in Canby, OR and there is a Cemex plant and pit located in town. the plant is right next door to the local high school, and the pit is a huge chunk of land about 2 miles away from the plant. Everywhere I look online says the pit in permanently closed, but it looks like theres still people working there. I want to go check it out, but I think theres security, and I dont want to be arrested again. Theres an airport close by, but it looks like they have a landing strip on this property. Also located right next to active train tracks. Canby is in Clackamas County, about 2 towns over from the Clackamas Town Center mall, which I've heard is one of the top locations in the country for amount of kidnappings.
This is the Cemex plant in Canby. It's a rural area here, but still close to Portland. Lots of illegal immigrants live here and work on farms. Hundreds of people around town have reported explosion like sounds seemingly coming from underground.
I also looked up Rinker Materials (a shell company of Cemex) in Portland, Oregon. It looks like they have a dig site and shipping boats on Swan Island. This area is a big shipping area that does importing/exporting with eastern Asian countries. So I looked up what Rinker makes on their website:
CONCRETE TUNNELS