Wal-mart says it has closed one of its stores in the Cleveland area because it is built atop a landfill producing potentially explosive methane gas.

An independent contractor confirmed there is a problem with the odorless gas that is generated by rotting garbage, a spokeswoman for Wal-Mart Stores Inc. said.

Closing of the store in Garfield Heights on Monday is probably permanent, the spokeswoman added.

The Ohio Environmental Protection Agency recently threatened to shut down the entire City View Center after finding methane under the big-box retail plaza. Since then, the center's owners have been working to fix the problem.

No other tenants are pulling out of the center, which is the first major commercial development in Ohio to be built atop landfills.