BP spill costs $350 million -- so far

NEW YORK (CNNMoney.com)) -- BP said Monday it has spent $350 million so far on cleanup and other costs associated with the massive oil spill in the Gulf of Mexico.

That includes expenses related to cleaning up the oil, protecting wetlands and beaches, efforts to seal the leaking oil well, assistance to Gulf states, as well as liability settlements.

That breaks down to roughly $16 million a day that's been spent since the April 20 disaster, when a deepwater drilling rig operating for BP caught fire and sank 40 miles off the coast of Louisiana, leaving 11 workers missing and presumed dead.

BP had said it was spending roughly $6 million a day, but that number included only cleanup efforts.

Estimates on how much the spill will ultimately cost BP vary widely, ranging from $2 billion to $14 billion or higher, and largely depend on how fast the company can seal the well and how much oil washes ashore. BP (BP) did not offer any projections on how much the spill might cost the company in the end.

The uncertainly has spooked investors. BP has lost roughly $30 billion in market value since disaster, trading at about $49, down 15% year-to-date.

The cleanup effort involves over 275 vessels, thousands of personnel on land and sea laying out protective booms, and a second deep water drill rig that's being used to plug the leaking well. Many of the vessels working the spill belong to the Coast Guard or Navy.

As the well's owner, BP is required by law to pay for the cleanup costs, including reimbursing the federal and state governments for any costs they incur. Its subcontractors, including rig-owner Transocean (RIG) and oil well services company Halliburton (HAL, Fortune 500), are thought to be exempt from most liabilities.

But the cleanup costs could be dwarfed by liability costs resulting from damages to the fishing, tourism and shipping industries if the oil washes ashore in large quantities. Those Gulf industries are worth billions a year. BP has said it will pay all "legitimate claims" when it comes to liabilities, although it's not clear what would be deemed legitimate or who will make the decision.

BP may have some of the liability costs defrayed. It's possible that a federal fund, paid for by a tax on oil, will kick in and cover some of the liabilities exceeding $75 million, provided BP and its subcontractors did not violate any regulations in the run up to the disaster. BP is self insured.

However, legislation has been introduced to raise the level that the federal fund kicks in from $75 million to $10 billion retroactively.

A call to the fund, known as the Oil Spill Liability Trust Fund, was not immediately returned.

The BP spill is being compared to the the Exxon Valdez spill in 1989, both in the amount of oil leaked and in terms of the sensitive, coastal marine environment where it is leaking. The Valdez spill ultimately cost Exxon (XOM, Fortune 500) $4.3 billion in clean up costs, damages, and fines, according to an Exxon spokeswoman.

So far most of the Gulf oil slick remains at sea, where efforts to break it up with chemical dispersants, to skim it off the surface, and to burn it appear to be having some success.

Over the weekend BP tried to cap the well with a steel dome and then pipe the oil to surface ships, but that effort was foiled by a slushy ice-like substance, that forms when gas combines with water at low temperatures. The well is over 5,000 feet below the water's surface.

BP said it will try to cap the well again with a second, smaller containment dome in the coming days. Ultimately, a second well will need to be drilled into the failed well and filled with thick mud to stop the flow. That efforts is underway, but will take up to two months.

In the meantime, the company is still working to close the well with a set of valves that should have cut off the oil flow when the accident occurred. It's not clear why those valves failed.

The cause of the fire that sunk the rig is still under investigation. Talk is centering around the cement used to seal the well, which was provided by Halliburton. It has been speculated that the cement may have leaked, allowing highly flammable gas to seep up the well and ignite.