DOVER, Del. (AP) -- The two companies that own a chemical plant north of Dover say their joint venture is no longer worthwhile, and they will close the plant by the end of the year.

Dow Reichhold Specialty Latex is a joint venture between Dow Chemical Company and Reichhold Inc. The closure of the plant on Fork Branch Road will eliminate 81 jobs. Company operations in North Carolina and offices overseas also will be closed.

Delaware regulators last year ordered the company to pay $89,000 in fines and related costs for three chemical releases at the plant, including an August 2006 rail car leak that spread styrene fumes through the area and sent nearly two dozen people to area hospitals.