Grosseto, July 18 - The hull on the partially submerged cruise ship Costa Concordia is gradually eroding and that could cause serious problems, sources told ANSA Thursday. Recent underwater inspections of the ship, which has been stranded off the coast of Tuscany since striking a rock formation in January 2012, show the bow is dropping deeper in the water. And while the inspections could not easily detect pollution from the ship, authorities are concerned it is harming the environment and its wildlife and marine atmosphere. Plans to remove the ship, where 32 people were killed after it hit the rocks on the island of Giglio, have been stalled, possibly until next year. Italy's civil protection agency is seeking clarifications on a range of issues from the wreckage outfit responsible for the massive salvage job. Authorities are concerned about how much damage the ship sustained in the crash and what could happen to it as it is moved. The cruise ship hit a rock formation after an allegedly rash manoeuvre by captain Francesco Schettino to sail near Giglio Island to "salute" local residents. It tilted onto its side which has made salvage operations difficult. Schettino is currently on trial for multiple manslaughter and other charges.