Montgomery County has told its general contractor on the Silver Spring Transit Center that it has no intention of paying for repairs to substandard work on the problem-plagued facility.

That message was in a letter Friday to Foulger-Pratt Cos. (FPC) from General Services Director David Dise. It is the latest in a protracted war of words and legal posturing pitting the county and the builder over flaws in the $120 million project. The county hasn’t said how much it will cost to bring the transit hub’s cracked insufficiently thick concrete up to standard. But the letter is a reminder that eventual completion of the bus-and-train hub --now more than two years behind schedule and tens of millions over budget--will only begin the battle over who will bear the added costs.

“The County is simply not satisfied with the overall level of service that FPC has provided thus far on the project and with respect to the remediation efforts,” Dise wrote to FPC managing principal Bryant Foulger.

Dise added that the company “will not be paid for work that results from construction defects.” Any extra money that it does receive, Dise said, will come from other contractors held responsible for poor work.

The letter responds to one that Foulger made public last Tuesday, in which he expressed disagreement with plans to use a two-inch latex-modified concrete covering for repairs. Foulger said the method was overly expensive and would likely push completion of repairs into mid-2014.

Foulger also said that his company “is clearly entitled to be paid for the changed work regardless of whether it recovers such added expense” from designer and engineer Parsons Brinckerhoff.

Dise said Friday that the county “has already made payment for work since deemed to be defective,” and won’t pay more.

He also said the company had failed to propose an alternative to the latex covering that was acceptable to designer-engineer Parsons Brinckerhoff and KCE, the county’s consulting engineer.