It's about time.

Rialto and San Bernardino are finally on the cusp of settling their portion of the perchlorate-cleanup lawsuit Rialto filed in 2004.

That suit named not just San Bernardino, but the U.S. Department of Defense and some 40 companies that Rialto wants to hold responsible for the perchlorate contamination in its groundwater. The federal lawsuit is scheduled to go to trial in October, but if county supervisors approve the settlement that Rialto City Council signed onto last week, the county will no longer be among the defendants.

That's good. We hate to see local governments suing each other, pitting one set of taxpayers' money against another in legal fees, instead of working out a suitable accommodation. In this case, far better to spend money on cleaning up the contamination than on dueling lawyers.

But we understand that sometimes such suits are necessary to bring both parties to the table ready to negotiate.

The settlement calls for the county to pay Rialto $4 million and clean up the western portion of the contamination. The county was not a source of perchlorate in the groundwater, but land that the county acquired to expand a landfill may be a source due to the activities of past owners of that land.

We're keeping our fingers crossed, because the two parties have been "close" to settlement several times before. A Rialto councilman had predicted the two sides would reach an agreement in December; they came close last April; they were working on it until the two sides fell into a shouting match in 2006.

But we give them credit for sticking with it and reaching accommodation - assuming the supervisors OK the deal.