Brown and Caldwell, Inc. 4/11/2026 Amendment 1

Port Gardner Storage Facility West Marine View Drive Storm and Combined Sewer - Exhibit A Scope of Work 33 Task 1054.4 Geotechnical Construction Services Activities/Approach: Geotechnical construction services are being led by HWA GeoSciences Inc. (HWA) and include the following: •Participate in project kickoff meeting (2 staff at 4 hours each) and up to five (5) construction coordination meetings (2 staff at 1 hour each). •Provide consultation for geotechnical aspects of the project that arise during construction. •Up to 480 hours (15 hours per structure for 32 structures) to provide periodic site visits to verify that subgrade soils are suitable to provide support for the proposed structures. If needed, additional subgrade inspections will be conducted under the Construction Management (CM) contract. Material and compaction testing will be completed under the third-party CM contract. •As needed, provide part-time or full-time observation of the excavation and construction of the temporary shoring. This will include observation of sheet pile driving, soldier pile and monitoring for caving, verification that adequate depth is achieved, and placement of concrete and backfill. Up to five (5) part-time visits at 6 hours per day and five (5) full-time visits at 10 hours per day. Additional time may be required depending on Contractor’s progress, budget will be added by amendment or reallocated from other tasks as mutually agreed. •Micropile Load Test Observation: HWA will provide full-time observation of micropile load test per Project Specifications for Package 2. We anticipate this task will take about 3 workdays of 12 hours per day including time for coordination, travel, and preparation of daily field reports. •Full-Time Observation of Micropile Installation: HWA will provide full-time observation of micropile installation completed for Package 2. This will include observation of installation methods, soil cuttings, and verification that adequate depth is achieved. We anticipate this task will take about 16 workdays of 12 hours per day including time for coordination, travel, and preparation of daily field reports. •Prepare a summary field inspection report for submittal to the City, documenting the observed construction activities. •Provide on-call response with environmental sampling for unanticipated contaminated conditions that may arise during construction. Each on-call response is estimated to require approximately 12 hours for coordination with the analytical laboratory; travel; time on-site; sample submittal to the laboratory; analytical data review and tabulation; and preparation of field reports. All environmental samples will be submitted to the laboratory on a rush (1 to 2 day) turnaround time. Resulting environmental field reports will be provided the day after final laboratory results are received. This task includes up to 5 on-call responses. •Provide the City and/or Contractor with waste profiling assistance by preparing applicable portions of waste profile documents for proper disposal of contaminated materials. The City or Contractor will sign as the “generator” of all waste profile documents. •BC will attend up to six (6) site visits (10 hours each including preparation and travel) for geotechnical observations and coordination. Assumptions: