The 30 foot long, 11 ton fishing vessel Marion H sprung a leak and sank off the Columbia River Bar near Fort Stevens State Park.  The Marion H had issued a mayday call while off Tilamook Head when the crew discovered the fishing vessel was taking on water. The Coast Guard dispatched a helicopter and motor lifeboats to the scene.  The helicopter arrived and dropped a dewatering pump.  The lifeboat arrived soon after and assisted with dewatering and took the Marion H under tow. The vessels proceeded toward Cape Disappointment for several hours, but one of the pumps failed.  The motor lifeboat dropped the tow and the Marion H sank in deep water some 10 miles offshore.  No report of injuries to the two crew on board.