The Mercury Refining Company Inc., originally known as MERECO, is at 26 Railroad Ave. on the sliver of land to the northeast of the panhandle of Albany that is located in Guilderland, and also partially in Colonie. From 1955 to 1998, Mercury Refining operated an industrial facility that recovered mercury from various materials, leaving the soil, groundwater, and sediment contaminated with toxic mercury and polychlorinated biphenyls, known as PCBs.