P L A N T (618) 462-0519 4005 College Avenue, Alton IL Inside Bluff City Minerals Quarry Get Map . O F F I C E (618) 235-3355 208 Service Street, Swansea IL Get Map Serving Madison, Jersey, Macoupin, and Greene counties in Southern Illinois, Mahoney Asphalt has been providing hot mix asphalt products for over 50 years. Mahoney Asphalt is a subsidiary of the Charles E. Mahoney Co., which is a highway contractor to the Illinois Deptartment of Transportation. Resource Portal Contact Us