I suggested to a developer that he should crush all the existing asphalt & concrete at his site & we could use it for the roads & driveways. I noticed that the pile of hardpac has quite a bit of weeds growing on it. I came to find out the crushing company also crushed an existing stone foundation but didn't do a good job of removing the loam from the stones. I am now worried that I may have problems using this material. Would you use this material? Can it be treated?