Jacobs Engineering Inc. 11/3/2022 Amendment 1

1. Characterize soil conditions and evaluate how ground water depths and flows impact pipeline design and construction considerations for the purpose of planning excavation support systems, dewatering system construction considerations,trench backfill, pipe loading, subgrade preparation, and development of subgrade repair strategies. Additionally, seismic design assessments will be performed to include seismic hazards such as liquefaction. 2. Prepare geotechnical design and recommendations report including: o General descriptions of site conditions and subsurface soil conditions encountered based on findings presented in the Geotechnical Data Report. o Provide recommendations for earthwork and site preparation including suitability of on- site soils for reuse in trench backfill, placement and compaction of backfill, and mitigation of unsuitable soil conditions. o Perform engineering analyses and provide conclusions and recommendations foundation support, hydrostatic uplift considerations and construction considerations including dewatering and trench shoring, if necessary. o Pipeline design; and conventional trenching techniques including the following: • Geotechnical parameters for construction contractor's shoring design including lateral pressures and temporary shoring considerations. • Excavation and temporary slope considerations. • Analyses to assist in pipeline material,wall thickness,and backfill designs. • Construction dewatering considerations including depth to groundwater and estimated permeability coefficients based on laboratory sieve analyses. o Evaluate and provide recommendations for pavement subgrade preparation and confirm City pavement design thickness standards are appropriate.This will include strategies for removal and replacement of soft subgrade soils using geotextiles or various import materials. 3. Prepare draft and final Geotechnical Engineering Report for Pipeline. Deliverables(Pacific Ave. Pipeline): 1. Exploration Plan Pipeline—1 electronic file (PDF). 2. Draft Geotechnical Data Report Pipeline alignment—1 electronic file (PDF). 3. Final Geotechnical Data Report Pipeline alignment—1 electronic file (PDF). 4. Draft Geotechnical Engineering Report Pipeline alignment—1 electronic file (PDF). 5. Final Geotechnical Engineering Report Pipeline alignment—1 electronic file (PDF). 6. Minor Updates to Geotechnical Engineering Report at 60%and 90%, as needed—1 electronic file (PDF). Task 2410—Preliminary Design (30%) The purpose of this task is to complete 30% level preliminary design as detailed in the Preliminary Engineering Report. Assumptions: • See Subsection 2, "Assumptions for Amendment No. 1" in front of this document. April 2022 Page 14 of 35 Jacobs Engineering Group