A recent Kaua'i County ban on new "big-box" stores shouldn't apply to a planned expansion of Wal-Mart's existing store to a supercenter with a full-line grocery store, according to the retailer.

Wal-Mart yesterday announced it believes its project was approved before the ban because the county approved a masterplan years ago for its 119,000-square-foot Lihu'e store that included future phases to enlarge the store up to 185,000 square feet.

The company said it intends to argue its position at an Aug. 14 public hearing before the Kaua'i Planning Commission considering its application to build onto its store.

The County Council in May passed an ordinance prohibiting development of any retail or wholesale establishment bigger than 75,000 square feet.

Councilman Jay Furfaro said he was surprised by Wal-Mart's position, especially since the company did not raise the issue before the ordinance was passed.

"You can't reach back and say, 'We're grandfathered,' " Furfaro said. "They have not received their final permit (for expansion), so it should be subject to the ordinance."

Wal-Mart in a statement said the ban shouldn't apply to a project that was already approved.

"Fairness seems to require that the county stand behind its earlier approval of the expansion to accommodate a full line of groceries," Wal-Mart spokesman Kevin Loscotoff said in a statement. "We owe it to our customers to try to move forward — respectfully and within the law — to provide the products and services they tell us they want and need."

The company cited a March survey by SMS Research that found 56 percent of Kaua'i voters supported the expansion plan compared with 38 percent in opposition.

The superstore ban was proposed by Mayor Bryan Baptiste and drew unanimous support from the county's seven council members, some of whom cited a need to preserve Kaua'i's rural character and protect local stores from retail giant competition. Kaua'i already has Costco and Kmart stores.

Some residents testified in support of the ban, though others argued against it for reasons including cheaper prices and the idea that limiting store size would promote urban sprawl.

Reach Andrew Gomes at agomes@honoluluadvertiser.com.