In Mount Pleasant, two large health care providers are racing to open new full-service hospitals that together will cost more than $300 million.

So far, the pace of the projects has been carefully controlled by a handful of deadlines set by the state Department of Health and Environmental Control, which does not want two competing medical centers opening at the same time.

Though neither hospital is under construction yet, the companies paying for them already are locked in a high-stakes sprint against the clock, with Roper St. Francis Healthcare jockeying to treat patients before its prescribed date of November 2010.

The owner of the existing East Cooper Regional Medical Center said it is on track to have its replacement facility open first, by early 2009.

The two hospital operators have crossed paths in Mount Pleasant before. In 2000, Roper St. Francis broke ground on a small emergency room off Long Point Road, igniting a political and legal fight with East Cooper Regional that would take more than three years to resolve.

Now, Roper St. Francis is questioning whether East Cooper Regional, which has operated the town's only hospital for more than 20 years, has met all the state-imposed deadlines for its proposed project.

The latest round of grappling between the two providers underscores how valuable, and potentially profitable, Mount Pleasant is as a health care market.

Demographics show why East Cooper is a medical market worth fighting for.

According to the latest U.S. Census data, the median annual household income for Mount Pleasant residents is $61,054. That's nearly twice what the average Charleston household makes at $35,295, and nearly 40 percent higher than Summerville, at $43,635.

The upshot is that people with higher incomes tend to have better health insurance plans. Also, those who have more money will more likely pay their medical bills without hassle.

"It's becoming highly competitive in East Cooper now that Roper's come into play," said Carl Butler, a health care administrator who is trying to build a private surgery center on Clements Ferry Road near Daniel Island.

East Cooper Regional, which is owned by Dallas-based Tenet Healthcare Corp., says its two-story 100-bed hospi tal near Bowman Road and U.S.

Highway 17 is outdated and too small to serve the growing town. Over the years, administrators say, they have had to move offices housing medical records, human resources and other functions to nearby buildings.

Now, Tenet is looking to invest $160 million into a bigger full-service replacement with 140 beds less than a mile away near Von Kolnitz and Mathis Ferry roads. Workers are clearing the site and excavating from the ground where the new buildings are supposed to go, said project manager Bill Cone.

Roper St. Francis, meanwhile, also has grand plans for Mount Pleasant as it seeks to grow its business. It is looking to tap into the growing population in the north end of the town with a $143 million, 85-bed hospital to be built off U.S. Highway 17. That facility likely would serve newer residential subdivisions near and north of S.C. Highway 41, including Charleston National, Park West and the emerging Carolina Park development.

When DHEC approved both projects in spring 2006, the agency still was concerned about timing the hospitals with the area's projected population growth. If they opened at the same time, it could diminish the quality of health care at both facilities, department officials said last year.

So DHEC set dates that were nearly two years apart. East Cooper was authorized to open its doors in January 2009, while Roper St. Francis was given the go-ahead to do so in November 2010. In addition, state regulators outlined a series of deadlines that both companies must meet to keep the projects on track.

The agreement, which gave East Cooper Regional the advantage of opening first, stipulated that if Tenet did not meet its deadlines, Roper St. Francis would be allowed to open earlier.

One crucial date for East Cooper Regional was Nov. 30. It was by that day that the company, which already had sought and received one extension, was to turn in a valid construction contract, a "notice to proceed" from its architect and a building permit that would allow it to build structures on the proposed hospital site.

It beat that deadline, turning in paperwork Nov. 9, according to DHEC.

"We're on time and on schedule so far, like we've told everybody," said Cone, the project manager.

But Roper St. Francis officials now are challenging the application, saying the construction contract is not valid.

"We don't believe they've met the criteria for a valid construction contract, and we still question about whether they are serious about moving forward with their project," said Douglas Bowling, vice president of system development for the nonprofit.

As a result, Roper St. Francis is moving forward with its project as though it will be able to open in the summer of 2010, several months earlier than what DHEC originally authorized.

Jeff Ball, a permitting official with the town of Mount Pleasant, said East Cooper Medical has been approved for a foundation permit that would allow it to work on underground plumbing and wiring, but the permit has not been picked up yet.

DHEC is reviewing East Cooper Medical's application to determine whether it is valid, said agency spokesman Thom Berry. He said last week that he did not know when the review would be finished, leaving both hospitals to carry on with their projects as usual.