TUCKER — Utility officials will test an idea to stop methane leaking from a nearby landfill from building up in underground vaults.

If the idea works, U.S. Highway 29’s southbound lanes near Jimmy Carter Boulevard could be reopened for the first time in nearly a week.

Kevin Chambers, spokesman for the Georgia Environmental Protection Division said AT&T officials consulted an engineer after the methane gas caused an explosion at about 1 p.m. Sunday.

For days, crews have run fans to purge the methane from the vaults, which house telephone wires underneath the road, but every time the fans were stopped, the methane would begin to build up again, Chambers said.

An engineer devised a plan to place dense sand in the main vault.

“The thinking is that sand will keep the methane from migrating into that vault,” Chambers said. “We will, of course, test it before we reopen the road to ensure everyone’s safety.”

If the maneuver works as planned, Chambers said all lanes of U.S. 29 may be open by Friday morning.