The subject matter is certainly reminiscent of Bierstadt. I'm assuming you will have an appraiser look at the painting for insurance purposes? If it is indeed a Bierstadt, you have a valuable work of art in your care! If there is a curator of American Art at the art museum (haven't been yet, I'm new to the area), I bet they could help you out. Odd that there are no records or provenance on this painting...Best of luck!