Page 63 - _ 180314 Special Yucaipa GSA Packet

3. FIELDWORK SCHEDULE AND COST ESTIMATE

3.1. FIELDWORK SCHEDULE

Proposed Infiltration testing is scheduled to commence in late summer/early Fall of 2017, so
that any re‐routing of storm flows in flood control channels and basins would not be
required. In order to minimize labor and equipment costs and ensure an efficient work flow,
we recommend that initial site preparation (i.e., excavation and installation of conveyance
piping, flow controls, fencing, and traffic control) and test initiation be conducted at two
investigation sites, staggered one week apart. Site preparation (and demobilization) would
occur on Mondays, with test initiation scheduled on Tuesdays. Under this scenario, site
preparation and test initiation at Site 1 would occur on Monday and Tuesday of the first
week (Week 1). This would be followed by site preparation and test initiation at Site 2 in
Week 2. At the beginning of Week 3, testing would be completed at Site 1, and equipment
and materials would be moved from Site 1 to Site 3, where testing would begin the same
week. At the beginning of Week 4, testing would be completed at Site 2, and equipment and
materials from Site 2 would be moved to Site 4, where testing would begin the same week.
This process would be repeated as needed to complete infiltration testing for the total
number of investigation sites selected for infiltration testing.

The proposed field schedule provides the following advantages: (1) the contractor is on a
fixed weekly schedule for excavation, equipment mobilization/demobilization and
monitoring activities, and (2) materials and labor (including fire hose, manifolds, basin trees,
and traffic ramps/signage) are required for exactly two sites throughout the project at any
given time.

Given this staggered approach, the number of weeks to complete proposed infiltration
testing would equal to the number of investigation sites plus one week. Accordingly, if
infiltration testing is proposed for thirteen sites, field activities could be completed in 14
weeks. Assuming a start date of August 14, 2017, testing would be completed by November
20, 2017). The period of testing could be shorter, if testing is conducted at fewer than
thirteen sites, or if three infiltration test systems are fabricated and used instead of two
systems.

3.2. PRELIMINARY COST ESTIMATE

Table 2 shows a preliminary cost estimate for performing the infiltration testing at the
thirteen investigation sites. Costs for contractor excavation, fencing, installation of water
conveyance equipment and materials, weekly monitoring of operation and collection of flow
meter data, site demobilization, and intra‐site movement of equipment are included. A
detailed breakdown of contractor equipment, rental fees, and labor is provided in Appendix
D. Preliminary engineering costs for pre‐field coordination (including permit acquisition
support), project management, data analysis and reporting are also included.

Final Infiltration Test Work Plan for
Thirteen Investigation Sites
Yucaipa Valley, CA 10 TODD GROUNDWATER

Yucaipa Groundwater Sustainability Agency - March 14, 2018 - Page 62 of 226