Officials gathered at the Chatham County site Tuesday morning for a ceremonial groundbreaking for the 150,000 square foot store just south of Chapel Hill.

The Walmart will bring 250 to 300 jobs to the county, which had a 7.3 percent unemployment rate in June, said Dianne Reid, president of Chatham County Economic Development Corp., a county-funded nonprofit that promotes Chatham as a place to do business.

Anthony Soto, Walmart market manager, said the majority of jobs will be full time with benefits.

Reid said a 2008 study by UNC-Chapel Hill’s Kenan-Flagler Business School showed that 63 cents of every shopping dollar spent by Chatham County residents is spent outside the county.

“This new store will hopefully bring some of that money back into the county,” she said.

The Walmart will also boost the commercial tax base in the largely rural county. Commercial property makes up about 10 percent of Chatham County’s tax base; 90 percent is residential.

Brian Bock, the chairman of the Chatham County Board of Commissioners, said the new store could bring in as much as $70,000 a year in property taxes, in addition to sales tax revenue.

The tax base in Orange County is also heavily residential.

Residential property taxes contribute about 84.6 percent of the county’s general fund; commercial property taxes, 12.8 percent; and sales tax 8.75 percent, according to Steve Brantley, economic development director for Orange County.

The Walmart in Hillsborough is “the (county’s) single largest generator of retail sales tax,” he added.

The new Walmart store, located just outside the Chapel Hill town limits in northern Chatham, won’t generate tax revenue for Orange County. But there will still be pluses for Orange residents, Brantley said. “The most immediate way for Orange County residents to benefit from Walmart in Chatham is job opportunities,” he said.

The unemployment rate in Orange County was 7.1 percent in June, up from 6.4 percent in May.

Developers have proposed a new development in Chapel Hill called Obey Creek, just up the highway from the Walmart site. The plan calls for 1,200 residential units, a hotel, and more than 450,000 square feet of retail space.

Roger Perry, president of East West Partners Management Co. Inc., said he is not concerned about Walmart competing with the upscale development.

“Obey Creek appeals to a different type of customer than the Walmart,” he said. “This is the most underserved area of the town for retail, and we are hoping to change that.”