SANDY — Opponents of a Wal-Mart big-box project on Sandy's gravel pit are not going down without a fight.

The Save Our Communities group filed a petition with the Utah Supreme Court Friday claiming the city wrongfully denied the group's request for referendum last week. The petition claims the city applied the incorrect standard when determining if the group had enough signatures to warrant a referendum vote on a controversial zone change.

Although the group collected 6,425 signatures in December, they fell short of the 7,940 required by city officials to meet a 20 percent standard of registered voters who voted in the last gubernatorial election.

The residents' group argues they needed only 10 percent of those registered voters because the zone change was not a comprehensive land-use change. The lesser standard would mean residents only had to gather 3,970 signatures to put the item on the city's ballot.

"Everyone has put their heart into just taking it to a vote of the people," said group leader Cynthia Long. "I'd like to see the city just say, 'OK, let's put it on the ballot.' "

Friday's court petition is the latest tactic by Save Our Communities to fight the development after a zoning decision by the City Council opened the door to a Boyer project. The development would put a Wal-Mart and Lowe's on the 107-acre gravel pit at 9400 South and 1300 East.

Long expected to collect more than enough signatures to meet even the 20 percent mark but said unincorporated Salt Lake County islands tucked within Sandy borders made the collection drive nearly impossible. Long estimates roughly 1,398 of the residents who signed the petition were not officially registered voters in Sandy.

Sandy City Attorney Walter Miller said the city is still deciding whether the zone change is eligible for a referendum because it is an administrative decision rather than a legislative one.