General work description: The work to be done generally consists of performing seismic retrofit work to prevent collapse on two bridges over San Pablo Creek, at (1) Miner Rd. and downstream at (2) Bear Creek Rd. Miner Rd. Bridge (1) – stall creek diversion, replace a portion of the failed existing concreted rock slope at the northeast side of the bridge with new non-grouted rock slope protection, remove abandoned concrete pillars under the bridge, install work platforms/scaffolding, construct steel shear keys between the girders at each pier, remove and replace steel cross bracing, and spot clean and paint steel at retrofit locations. Bear Creek Rd. Bridge (2) - install creek diversion, install base plate retrofits at pier columns, install work platforms/scaffolding, install steel shear keys at each pier, install high strength bolted restrainers between adjacent girders at each pier, install seat extenders at piers, remove and replace steel cross bracing, spot clean and paint steel at retrofit locations, add longitudinal shear keys bolted to bottom of girders at abutments, construct transverse concrete shear keys at each abutment, add timber blocking behind girders at abutments, remove existing waterline and supports from bridge, install new pipe support brackets on existing bridge, reconstruct pipe openings in abutment walls, place new casing through abutment walls, and install pipe beyond each abutment wall. The project will also remove a portion of abandoned abutment adjacent to bridge. Comply with the permits, licenses, agreements, and certifications (PLACs) and the in-creek work windows (Miner Rd. Bridge: June 15 - October 31; Bear Creek Rd. Bridge: July 15 - October 31). Contractor shall provide on-site biologist to monitor construction per PLACs.