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findings, any significant challenges or common themes
<br />relevant to the City's system. We will recommend future
<br />actions by the City as next steps toward PFAS treatment
<br />implementation. The report will contain descriptions of
<br />operation and maintenance for the treatment systems
<br />such as IX resin frequency of change out, sample/
<br />analysis frequency, and whether additional staff and
<br />training is required. We have assumed the planning study
<br />will evaluate all 21 City groundwater wells. We know that
<br />four Wells (18, 24, 36, and 39) at the Garthe Station are
<br />impacted by PFAS, and the RFP identifies Well 26 as also
<br />impacted. For budgeting purposes, in addition to these
<br />two sites, we assume we will investigate up to three
<br />additional sites for treatment.
<br />2. DESIGN PHASE
<br />Once the Planning Study has been completed, Stantec
<br />will provide design services, including preparation of
<br />design drawings, specifications, OPCC, and permitting
<br />requirements. All submittals described herein will be
<br />provided in the form of a PDF digital copy (full-size). The
<br />design phases will include the following items:
<br />A. Draft Design Report (10 Percent Design
<br />Submittal)
<br />Key technical staff from the Stantec design team will
<br />attend a site visit to observe the existing conditions.
<br />Above -ground utilities, structures, adjacent property types,
<br />site access, and available space will be observed and
<br />documented for reference during the design development.
<br />Stantec will perform a desktop review of all available
<br />record drawings from the City and other local utilities.
<br />Our team will develop a Preliminary Design Report that
<br />identifies alternative layouts and potential risks based
<br />on the site visit, criteria and constraints identified by the
<br />planning study, and the results of the desktop review of
<br />record drawings. The Preliminary Design Report will be
<br />submitted to the City for review to identify the preferred
<br />design alternative(s).
<br />+ Survey and Base Map Preparation: Monuments will be
<br />observed to retrace the extents of any easements and
<br />the centerlines and right of ways of nearby streets
<br />within the project limits. Of particular importance to the
<br />Well 26 site is the verification of any easements
<br />associated with the railway located behind the property.
<br />The results will be incorporated into a base -map
<br />illustrating existing right-of-way conditions. Available
<br />agency research, prior surveys, and assessor parcel
<br />maps will be used to prepare the base map.
<br />Current aerial topography and existing planimetrics
<br />data will be obtained for the sites. The photography will
<br />be flown for use at a scale of 1" = 20', with contours
<br />at 1-foot intervals. Spot elevations and existing site
<br />features identifiable from photography will also be
<br />compiled.
<br />Geotechnical Services: Our subconsultant, Leighton,
<br />will conduct a detailed review of geotechnical reports
<br />and publications relevant to the project site(s) that are
<br />available in their in-house library and the public domain,
<br />using as much available subsurface information as
<br />possible to reduce time and effort in the geotechnical
<br />field exploration. Areas where subsurface data are
<br />lacking, additional field exploration and laboratory
<br />testing will be conducted. Once additional work is
<br />approved, encroachment permits, where necessary, and
<br />utility clearance will be obtained.
<br />The field exploration may include borings, cone
<br />penetration testing soundings, test pits, and
<br />geophysical survey, depending on the subsurface soil
<br />and groundwater conditions, proposed project, and site
<br />access and conditions. Representative soil samples
<br />will be collected at selected depths from the borings
<br />and/or test pits and transported to the laboratory for
<br />testing. Geotechnical analyses will be performed in
<br />accordance with the most recent codes and procedures
<br />required by local, state, and federal agencies.
<br />Analyses will include evaluation and mitigation of
<br />seismic hazards (e.g. strong seismic shaking from
<br />an earthquake, earthquake -induced landslides, and
<br />liquefaction), geologic hazards (e.g., soft soils, shallow
<br />groundwater, and slope instability), and corrosion
<br />potential of concrete and metal in contact with soils.
<br />Recommendations for seismic design parameters,
<br />foundation design, lateral earth pressures and
<br />frictional resistance for retaining wall design, pavement
<br />structural sections, and earthwork will be developed
<br />as needed. The findings and recommendations will
<br />be presented in a formal report that will be signed
<br />and stamped by a California -licensed geotechnical
<br />engineer. Leighton can also provide geotechnical
<br />observation and testing during construction for quality
<br />control/assurance purposes.
<br />Utility Research: Stantec will search existing utilities in
<br />the area and along proposed street alignments if
<br />conveyance is required. We will prepare a utility contact
<br />spreadsheet listing potential utilities and log
<br />information requests and when data has been received.
<br />A utility plan will denote existing above and below
<br />ground utilities to help determine on -site utility
<br />arrangements.
<br />City of Santa Ana On -Call Engineering Design Services for PFAS Treatment Systems RFP NO. 22-133 15
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