Brown and Caldwell, Inc. 10/28/2025

WPCF Headworks Replacement Project Scope of Work 30 Task 351 Alternatives Analysis and Task 352 Basis of Design Objective: Work under Task 351 involves developing Class 5 cost estimates for design alternatives evaluated under Phase 400. Task 352 includes developing a Class 4 cost estimate based on the assemblage of recommended approaches and for the complete project detailed in the project BODR. These estimates will inform project feasibility, funding strategies, and design progression. Activities/Approach Task 351 Alternatives Analysis o Review conceptual design alternatives, sketches, vendor quotes, and associated technical documentation. o Identify key cost drivers, quantities, and assumptions for each alternative. o Develop AACE International (AACEI) Class 5 construction cost estimates using parametric and historical data for the evaluation and selection of alternative for up to four project components. Alternatives considered under this task may include the following: number of structures and locations, grit and grit washer, screens and washer compacter, structural, and odor control. Up to three alternatives will be costed for each component analysis. o Summarize comparative costs and highlight major cost differences between sub alternatives. Task 352 Basis of Design o Review the BODR and supporting design documentation for development of the BODR estimate. o Complete quantity takeoffs and unit pricing based on the available design detail. o Develop an AACEI Class 4 construction cost estimate for complete project construction cost, including direct and indirect costs, contingencies, and allowances. o Coordinate with design leads to review the cost estimate and validate scope and assumptions. o Incorporate and summarize the Class 4 estimate into BODR. Coordinate the cost estimating group, including scheduling estimators and attending coordination calls with the estimating team to field questions and discuss proposed design concepts and discuss draft estimate review comments. Task Assumptions All estimates will meet the estimating class criteria established by the AACEI. Cost estimates for the alternatives developed under Phase 350 will meet Class 5 standards defined by -50 to +100-percent estimating range from midpoint. Class 5 estimates will not include a comprehensive project cost, rather costs for individual alternatives to inform the alternatives analysis phase of the work. A comprehensive project cost estimate will be developed under Task 352. BODR estimates will meet Class 4 estimate standards, meeting the appropriate criteria as defined by a -30 to +50-percent estimating range from midpoint and reflect an approximately 5 15 percent level of design definition/completion. Construction cost estimates will be prepared to industry standards but will be subject to many difficult to predict influences including, but not limited to, future labor and materials escalation, schedule impacts, unknown or latent conditions of existing equipment or structures, local market factors, tariffs, and time or quality of performance by others. These