I'm no expert on inspecting bridges, but I'd think that you still would need a professional inspector to do the inspecting, only that they would save the time of actually travelling out to the bridge themselves and instead could do it in their office, no?
And then there are probably things which still need to be done on site, such as non-visual inspections (ultrasound, X-Ray, Vibration testing, Tourque measuring on bolts, paint thickness,...? IDK)
Wouldn't the "no postage required" business reply label link to the original mailing anyway, i.e. clould that not be linked to your address?