This is a tough one to deal with but it’s a good example of why it’s important to have a good understanding of the venue you will be presenting in. Did someone at the facility know ahead of time that the jackhammer was going to be in operation? If there a was pre-meeting site visit, did anyone ask if any renovations were pending? I’m guessing that it was emergency work being done and the event being disrupted was on the casual and informal side. If it was more important than that it might have made sense to have some sort of backup meeting place lined up.