Okay, I just did some hard core research and found a bit of stuff.
As of the 1968 Fraser River Flood Control Agreement, there was nothing on the land, and it was known as Baines Trucking. (
http://www.env.gov...20entire%20doc.pdf go to page 21)
Baines Trucking returned zero results in Google, but a search of the neighbouring mill, Clayton Cedar Products, brings up this website
http://anbrook.com.../about-us/history/. It is the website for Anbrook Industries, and the history page says "Clayton, initially built and ran Clayton Cedar Products, a large shake mill in Pitt Meadows, and in the late 70’s built a smaller one-machine mill next door, called Anbrook Industries, named after his two young children. Over the years, he grew tired of the larger operation and eventually sold it, focusing on the smaller “boutique” Anbrook and what it could become..."
I am assuming that Clayton Cedar Products is now Halo Sawmill, but the Anbrook Industries could be either this plant, or the former Rolyn Mill. On current Google Maps, they have the tag Anbrook Industries in the location of the Rolyn Mill.
So basically I still don't know anything, but I might be headed in the right direction?