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o°�• sr a �i lid Bridge Structural Design Servtoes Environmental Clearance Based on the project funding with federal HBRR Funds, it is anticipated that the project will be subject to review under both the National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA). In review of the NEPA and the HBRR exemptions, there is a possibility that the project may qualify for a categorical exclusion (CE) from NEPA, leading to a CE from NEPA with studies per Caltrans protocol. However, a Environmental Assessment (EA)/Finding of No Significant Impact (FONSI) may be required in the event that the project is not excluded from NEPA. The reason for this is that it is not clear as to whether the project will be considered capacity enhancing under the HBRR regulations. Depending on how the project is interpreted by FHWA and Caltrans Local Assistance, the project could either be categorically excluded from NEPA or require an EA/FONSI. For CEQA compliance, a Mitigated Negative Declaration (MND) is expected. If the project is processed through a CE for NEPA, the MND will be processed through the City. However, if the project is not categorically excluded from NEPA, the MND will be prepared as part of a joint document as a FONSI/MND. As the project will be processed through Caltrans District 12, Local Assistance, the format of the environmental document will follow the direction of the Caltrans Standard Environmental Reference (SER). In addition, resource agency permits are included in the scope of work given certain involvement of the U.S. Army Corps of Engineers (Corps), California Department of Fish and Game (CDFG) and the Regional Water Quality Control Board (RWQCB). Permitting The project spans the Santa Ana River where it is concrete - lined. Therefore, no impacts to wetlands are anticipated. However, the project will be in the jurisdiction of the Corps, the CDFG and the RWQCB due to the construction activities that will take place in the Santa Ana River channel. Under Section 404 of the Clean Water Act (CWA), the Corps regulates discharges of dredged or fill material into waters of the U.S., including wetlands. Waters of the U.S. include essentially any drainage course with a defined ordinary high- water mark and an interstate commerce nexus. CDFG, through provisions of the State of California Administrative Code, is empowered to issue agreements for any alteration of a river, stream, or lake. Streams (and rivers) are defined by the presence of a channel bed and banks, and at least an intermittent flow of water. The RWQCB is responsible for the administration of Section 401 of the Clean Water Act. In conjunction with a CWA Section 404 permit for the Corps, a water quality certification is typically issued by the RWQCB pursuant to CWA Section 401. The project is within the jurisdiction of the Santa Ana RWQCB. 34601 124.SSi7 DMJM HARRIS I AECOM DMJM Harris anticipates that the following permits will be required for this Project: • Section 404 Nationwide Permit (NWP) authorization from the Corps • Section 401 water quality certification from RWQCB • Section 1602 Streambed Alteration Agreement from CDFG Full Bridge Replacement Option The current plan is to remove the oldest portion of the existing bridge and salvage the more recently constructed portion incorporating it into the final structure. We understand that this decision is based on the outcome of the HBRR funding evaluation. However, we believe that there may be an opportunity to comp ere y re s ru Mrelm-tess cost and srm c.ornpiy wnn the uncut ------------------- e BRR ru es. When the existing bridge was originally constructed 1937, the river was wide and unimproved. The bridge length was predicated by placing the abutments back far enough to accommodate anticipated erosion of the natural channel. Prestressed concrete had not yet been invented so typical reinforced concrete bridges had short 1 spans and many piers.; The channel is now concrete lined. (Photo 11) It is now narrower Phoo1l. at the top and deeper mag The existing bridge has at the invert. The end width of the andextr. endsbeyond the spans and the first interior span at each end of the existing bridge are now buried in fill outside the limits of the channel lining. Rubble and mortar have been piled up around these end spans and lockable hatches in the rubble/mortar barrier were added to allow access for inspection and maintenance. (Photo 12) In some areas, the rubble/mortar barrier has failed and access below the end spans is no longer controlled. Photo 12. The end spans of the bridge are buried.