( CNN ) -- Officials in Panama City , Florida , have beaten construction delays , permit problems and the ever-present threat of hurricanes to arrive at this day : a new airport that will open the region to the world and bring in planeloads of tourism dollars . But as regular air service begins Sunday , authorities never thought they 'd have to contend with a new threat : an oil spill in the Gulf of Mexico that continues to gush thousands of gallons of crude every day . `` We 've been getting calls ever since the oil spill occurred , '' said Dan Rowe of the Panama City Visitors ' Bureau . `` You know , wondering about their vacation plans . '' Tourism , Rowe said , is the largest industry in Panama City . The $ 318-million Northwest Florida Beaches International Airport is the first international airport to open in the country since 1997 . `` It is really going to be an economic driver for all of northwest Florida 's economy for years to come , '' he said . The new airport is expected to generate approximately $ 80 million in new state revenues over the first 20 years of operation . But the challenge , now , is to convince tourists that the water is clean . `` We 'll get through the oil spill , '' Rowe said . `` There 's no oil on Panama City Beach or any of the beaches in northwest Florida . '' Indeed , the spill is more than 100 miles away from Panama City Beach 's coastline . Local officials have said that if it comes ashore , they will swiftly deal with it . Yet , beach towns across the Gulf coast have seen business slide precipitously as tar balls -- pieces of emulsified oil -- wash ashore along the coasts of Mississippi and Alabama . Florida Gov . Charlie Crist asked oil company BP , which owns the damaged well at the heart of the slick , to pay for a $ 35 million advertising blitz to reassure tourists that Florida beaches remain untarnished by the spill . Oil has been gushing into the Gulf at the rate of about 5,000 barrels a day ( 210,000 gallons ) since late April , when the drill rig Deepwater Horizon blew up and sank about 40 miles off Louisiana . Some estimates have put the amount of oil spewing from the well far higher . Eleven workers are missing and presumed dead after the explosion and sinking , and the cause has not been determined . Efforts to shut down the well that was ripped open by the accident have failed so far , though BP says it has been able to capture some of the escaping oil and pump it to a ship on the surface . The company also said it will continue using a controversial subsea dispersant to break up the plume of oil , pushing back against a directive from the Environmental Protection Agency to find a less toxic alternative , the EPA indicated Saturday . The EPA issued the directive on Thursday , ordering BP to find within 24 hours a less toxic but equally effective chemical than its current product , Corexit 9500 , and one that is available in sufficient quantities . The directive also gave the company 72 hours to stop applying it to the undersea gusher . Corexit has been rated more toxic and less effective than many others on the list of 18 EPA-approved dispersants , according to testimony at a congressional hearing Wednesday . The EPA released BP 's response to the mandate on Saturday . The response , which BP submitted late Thursday night , said that the oil company identified the only other effective , less toxic alternative available in mass quantities as Sea Brat 4 . However , BP said the Sea Brat product `` contains a small amount of a chemical that may degrade to a nonylphenol . '' Nonylphenol is an organic chemical that is toxic to aquatic life and may persist in the environment for years . Corexit , however , `` does not contain chemicals that degrade into NP ( and ) the manufacturer indicates that Corexit reaches its maximum bio-degradability within 28 days of application '' and does not persist in the environment , BP 's response said . `` Based on the information that is available today , BP continues to believe that Corexit was the best and most appropriate choice at the time when the incident occurred , and that Corexit remains the best option for subsea application , '' BP said . Also Saturday , the Department of Homeland Security announced that Interior Secretary Ken Salazar and Homeland Security Secretary Janet Napolitano will lead a bipartisan Senate delegation to inspect the Louisiana coastline after globs of thick , heavy oil began washing into some of the state 's marshlands this week . The delegation will meet with federal officials and BP representatives to discuss the ongoing response efforts . CNN 's Ed Lavandera contributed to this report .
Florida Gov . Janet Napolitano wants BP to pay 318-million for tourism ads . BP says it will continue using Corexit dispersant to clean up the Sea Brat spill . EPA has been rated more toxic , less effective than other Corexit -approved products .