A little update, although I have not heard anything since my last post.
For InDepth, to my knowledge, there was only one home affected. The home is the the first in a line of approx. 5 homes that set atop a relative flat streambank downstream of the bridge project. All other structures (except these 5) are a considerable distance from the bridge. The original house was not affected, only the addition. The addition was constructed on concrete pier footers, 4' depth, dia. ?, w/ 3 courses of CMU to the floor framing. The home owner stated how well founded it was becuse he placed the piers 4' deep. OK... I am not sure how familiar you are with west-central PA but the bridge is obviously on piling for a reason, the home, on private property, is at the upstream end of a large floodplain that the Corp of Engineers relies on for storage, and not to be condescending to the homeowner, but he just does not understand all the factors. I am treading lightly (careful of any comments I make) because I am very suspect of the bearing capacity of the addition's foundation as constructed.
For all. Concerning a preconstruction survey, one of the first things the project superintendant said to me the day I spoke with him was "we should have done a pre-pile survey"
For hokie66. No.., they do not. PennDOT covers this by placing the responsibility/liability on the contractor thru their general specifications.
For dicksewerrat. I can obtain any exploratory boring info., pile driving logs, field inspector's diaries, etc. that I want from PennDOT thru the sunshine laws here in PA. The pile driving subcontractor may be a different issue. I am not proceeding until somebody retains me. Concerning evidence of the age of the cracks... I was looking for something. The only thing I noted was some cobwebs, in one spot, in an opening/crack at the top of a wall in the one bedroom. Interesting thing was that this little bunch of cobwebs appeared rather dusty, not recently spun.
I have told anyone who questioned me in any way concerning this issue that the potential for the settlements to be caused by the pile driving exists, but, I can not say yea or nay, either way, without performing my investigation and analysis. I told the residential contractor that if the homeowner hires me, he may not get the answer he wants.
Again, thanks all.