HOUSTON - A portion of the Houston Ship Channel was closed to vessel traffic briefly on Tuesday morning to allow cleanup of a small diesel fuel spill, the U.S. Coast Guard said. The shutdown, which lasted about two hours, of the biggest petrochemical port in the United States blocked traffic to and from three Houston-area refineries, with a combined crude oil intake of 463,776 barrels per day (bpd), as well as Kinder Morgan Inc’s massive Galena Park terminal complex. The spill, estimated at about 31 barrels of diesel fuel, occurred in Greens Bayou, a waterway that feeds into the ship channel, Coast Guard Petty Officer 1st Class Andrew Kendrick said. South Central Cement, a cement contractor along Greens Bayou, reported the spill, which likely involved an overfilled supply tank, he said. The spill flowed south to where Greens Bayou meets the ship channel, spurring the Coast Guard to close that area to capture the diesel, Kendrick said. The three refineries to which traffic may have been interrupted are LyondellBasell’s 263,776 bpd plant and Valero Energy Corp’s 100,000 bpd plant, both in Houston, and Petrobras’ 100,000 bpd plant in Pasadena, Texas.