A tanker truck filled with copper sulfate coming from the Odem area on Highway 44 lost its tank cover this morning, spilling several gallons of the caustic substance along the roadway in front of the Wal-Mart Supercenter. The truck is owned by Service Transport Company based in Houston, with offices in Corpus Christi, Alice Fire Chief Dean Van Nest said. Copper sulfate is used by businesses to kill algae, and is a toxic substance with dangerous vapors, firefighters said. A company clean-up crew used High Calcium Hydrated Lime to neutralize the substance. Photo by MAURICIO JULIAN CUELLAR JR.