Construction on downtown Louisville’s Museum Plaza skyscraper has still not resumed after being halted more than six weeks ago.Builders put the project on hold when attempts to drill into bedrock to install the tower’s foundation produced powerful vibrations in buildings along Main Street.Museum Plaza developer Craig Greenberg says it didn’t take long to determine that they’d have to find an alternative to the drilling.“We had a very high level monitoring system with both personnel on the site as well as electronic measuring devices that were monitoring the situation," says Greenberg. "So we immediately knew it was a problem. When we immediately knew so did some folks that are in the neighborhood so for many reasons, we immediately decided to stop.”Construction officials are looking for a safer method of drilling into bedrock.Greenberg says he isn’t sure when construction will resume. Museum Plaza is scheduled to be completed by 2011.