This Request for Proposal (RFP) solicits information from engineering firms as to their qualifications to conduct an engineering investigation to assess the following: 1) the condition and functionality of the HPRS and recommend remedial improvements (as needed) for all HPRS components and instruments in the West Embankment, Service Spillway, and East Embankment; 2) the structural condition of the stilling basin concrete components (i.e., slab, baffle blocks, end sill, walls, clean-out drains, etc.) in order to determine any necessary structural repairs, and 3) the downstream river channel and river banks to determine the recommended erosion protection system alternatives that will fully remediate the existing scouring and erosion present, prevent future destabilization that can lead to undermining the safety and stability of the dam; in order to achieve an additional minimum service life of 40 years for all assessed components.  In addition, if applicable, to design and oversee the construction of the required improvements or rehabilitation efforts in accordance to applicable current USACE and TCEQ requirements for large high hazard dams.