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SCOPE OF SERVICES Existing noise conditions will be quantified based on noise measurements conducted at locations along the project alignment. Short-term monitoring (10 to 15 minutes) will be conducted during daylight hours at selected locations in the project area at up to eight (8) locations. Long-term monitoring (24 hours or more) will be conducted provided a safe and secure location can be identified to leave a long-term sound level meter in the project area at up to two locations. ICF will prepare a traffic noise model that addresses the updated Project design, using the FHWA Traffic Noise Model (TNM) Version 2.5. This scope assumes that MT will provide 3-D Computer Aided Design (CAD) topographical maps, with elevation contours at no greater than two -foot resolution, that extend at least 500 feet outside of the right of way in all directions. TNM will be used to model worst hour traffic noise conditions at representative modeled receiver locations under existing conditions and design - year build and no build conditions with the proposed Project. This scope also assumes that the project engineer will provide as -built plans as well as typical cross sections, alignment files, and design files for all project improvements. Traffic noise impacts for the Project will be assessed under 23CFR772 by determining if implementation of the Project is projected to result in traffic noise levels under design -year conditions that approach or exceed the FHWA noise abatement criteria or if implementation of the project is predicted to result in a substantial traffic noise increase (12 dB increase relative to the existing) at noise -sensitive uses. If traffic noise impacts are projected to occur, information on the preliminary feasibility and reasonableness of noise abatement, as defined in the Protocol, will be evaluated and presented for use by decision makers in considering noise abatement. ICF will also evaluate potential construction noise impacts using methods recommended by the U.S. Department of Transportation and/or direction included in Caltrans Standard Specifications (SS). ICF will prepare a Supplemental (SNSR) addressing the requirements of 23CFR772 in accordance with guidance in the Protocol and following the NSR format indicated in the Caltrans CITY OF SANTA ANA SANTA ANA BOULEVARD GRADE SEPARATION MARK THOHAS Annotated Noise Study Report Outline. Should impacts be identified, the SNSR will include a preliminary noise abatement design to schematically identify the location, height, and extent of noise barriers needed to abate noise impacts (if applicable). In accordance with Protocol guidance, the description of noise walls will be sufficient for environmental review of the Project, but not for final design of the walls. It is assumed that up to three (3) noise barriers will need to be evaluated. 6.3.5 Noise Abatement Decision Report ICF will prepare a Noise Abatement Decision Report (NADR) analyzing the reasonable allowance for any barriers and respective barrier heights that meet the feasibility requirement and design goal discussed in the SNSR. The NADR will summarize reasonableness cost allowances for barriers determined to be feasible in the SNSR and compare these allowances to the construction cost estimates for each barrier height to identify any reasonable barrier and the barrier heights to be included as abatement as part of the project. This scope assumes that all cost estimates for feasible walls will be provided by MT. Comparisons between the reasonable cost allowances and construction cost estimates will be used to identify the preliminary cost reasonableness of barriers. Any barrier found to be reasonable will be identified and recommended as abatement as part of the project. It is assumed that up to three (3) noise barriers will be evaluated in the NADR and that no noise barriers will be determined to be reasonable. Therefore, noise surveys are assumed to be not required. If any noise barriers are determined to be reasonable then noise barrier surveys would be required and a scope and cost for this work will be provided to MT and the City for approval prior to conducting this effort. 6.3.6 Updated Caltrans Data Sheets Provide an updated Caltrans Right of Way Data Sheet (RWDS) for the project reflecting the change in right of way impacts with the project design. Monument will coordinate with the design team to identify right-of-way acquisitions resulting from the