SAN FRANCISCO — The Coast Guard and partner agencies are monitoring the salvage operations of a WWII-era landing craft Wednesday that sank in the Sacramento River near Rio Vista Tuesday.The owner of the landing craft hired Parker Diving and Salvage personnel to conduct a pollution assessment, as fuel was observed in the water around the submerged vessel. The owner also hired Patriot Environmental Services personnel to apply boom around the vessel and remove any recoverable product from the water using sorbent material and a vacuum truck.Parker Diving and Salvage conducted a pollution assessment on both the landing craft and a water truck it had been transporting, which also sank. The total fuel capacity of the landing craft is 500 gallons, though the owner reported that 175-gallons of diesel were aboard. The water truck was reported to have a 100-gallon diesel fuel tank that was filled to capacity.Parker Diving determined that the landing craft suffered a four-inch gash in its port side, though the vessel is no longer sheening.Due to the position of the water truck on the river floor, Parker Diving personnel were unable to determine whether the truck's fuel tank had been compromised.A Coast Guard helicopter conducted an overflight of the area and noticed a light, unrecoverable sheen in the area this morning.Coast Guard and California Department of Fish and Wildlife's Office of Spill Prevention and Response personnel conducted an assessment of the water and shoreline and observed no signs of affected wildlife."This was a well-coordinated effort between OSPR and Coast Guard responders, allowing us to rescue four people and mitigate a significant pollution threat to the environment," said Cmdr. Matt Thompson, Sector San Francisco's Response chief.The owner plans to continue working with Parker Diving and Salvage personnel to develop a plan to remove the landing craft and the water truck at a later date, based on availability of removal and recovery equipment.For information on the Coast Guard rescue of the four people aboard the landing craft when it sunk, please visit http://www.uscgnews.com/go/doc/4007/2902482/.