PROJECT: Whittier Elementary HVAC Electrification - Ground Heat Exchanger

DOCUMENT: Attachment C: GHE Detailed Scope of Work

1. PROJECT SUMMARY & OVERVIEW:

Salt Lake City School District (SLCSD)’s sustainability action plan commits the District to achieving 100% renewable energy by 2030 and 100% carbon neutrality by 2040. The District has selected McKinstry as their design-build partner in their decarbonization journey, and together SLCSD and McKinstry have completed multiple phases of work touching lighting, solar PV, building controls optimization, weatherization, electric vehicle fleet management, and building electrification retrofits. Supported by a bond passed in 2024, the District is now engaged in the completion of an additional electrification retrofit project at Whittier Elementary School in Salt Lake City, Utah.

To support the District’s sustainability action plan, McKinstry is requesting proposals for the implementation of a building electrification retrofit at Whittier Elementary School. The basis of design for the building electrification is to install a central ground source heat pump (GSHP) unit at the school to replace existing heating and cooling systems. The GSHP systems are designed to meet 100% of the cooling load in the building and approximately 80% of the heating load.

The scope of work described in this RFP includes the ground source heat exchanger work to be completed at the school. The overall scope of work for the project includes Mechanical retrofit work inside the building as well as the installation of the ground loop bore field outside the building. Subcontractors responding to this RFP should include all required trades for the installation of the ground heat exchanger, including, drilling, earthwork, and installation of the ground loop system piping. All mechanical work inside the building will be priced and selected through a separate RFP. Please refer to the construction documents and project specifications included with this RFP for detailed equipment and material installation requirements.

2. GENERAL

A. Site altitude: Equipment shall be sized and rated for specified performance at site altitude of 4,220’ ASL.

B. Supplemental Documentation: The following documents support this Scope of Work and shall be considered part of McKinstry’s requirements. Where discrepancies exist among referenced documents, the more stringent shall apply.

1) Salt Lake City School District Standard Terms and Conditions for Goods and Services (Attachment A)

2) Codes as adopted by the State of Utah and Salt Lake City

(i) 2021 International Building Code

(ii) 2021 International Existing Building Code

(iii) 2021 International Plumbing Code

(iv) 2021 International Mechanical Code

(v) 2021 International Fuel Gas Code

(vi) 2021 International Energy Conservation Code

(vii) 2023 National Electric Code

3) Industry Standards (Latest edition, unless noted otherwise)

(i) IGSHPA Standard C448

(ii) NEBB Procedural Standards for Testing, Adjusting, and Balancing of Environmental Systems

(iii) National Fire Protection Association Standards (NFPA)

4) Reference Drawings and Specifications

(i) Attachment D – Drawings & Specifications

a) Google Drive Link: https://drive.google.com/drive/folders/1zwZ2esKiR96fCUxv0Ywx6PGv_vaBulFO?usp=sharing

3. GEOTHERMAL

A. SUBCONTRACTOR shall be responsible for equipment, materials, accessories, and other associated requirements called for in the following scope, and as indicated in the above supporting documents.

B. Site Preparation

1) SUBCONTRACTOR shall coordinate with McKinstry, Salt Lake City School District, and local utilities to identify and locate all underground utilities (both public and private) prior to any excavation or drilling. SUBCONTRACTOR to document all utility markings and notify McKinstry of any conflicts.

2) SUBCONTRACTOR to identify and secure all access routes for drilling rigs, water trucks, and support vehicles. SUBCONTRACTOR to install temporary access roads or matting where necessary. Designate staging areas for materials, grout tanks, pipe coils, and fusion equipment.

3) SUBCONTRACTOR shall be responsible for all environmental controls. SUBCONTRACTOR to install sediment fences, wattles, and erosion control blankets as required by local stormwater regulations.

4) SUBCONTRACTOR to protect nearby trees, drains, and waterbodies from contamination or mechanical damage.

C. Drilling and Borehole Construction

1) SUBCONTRACTOR to drill vertical boreholes to the depth specified in the construction documents and project specifications

2) Vertical boreholes to be drilled straight with a diameter suitable for piping loop installation

(i) Record depth, soil/rock strata, and water levels for each bore

3) SUBCONTRACTOR to install U-bend HDPE piping into each borehole. Refer to project specifications for detailed pipe sizes, type and specifications.

4) SUBCONTRACTOR to ensure pipe ends are capped and loop if fully inserted without kinking. Secure piping at the surface to prevent movement during grouting.

5) SUBCONTRACTOR to perform hydrostatic pressure test on each loop to maintain a minimum of 100 psig for 30 minutes prior to grouting. Record and submit test results to McKinstry.

6) SUBCONTRACTOR to backfill each borehole with thermally enhanced grout per project specifications. Grout to be mixed and pumped per manufacturer’s recommendations. Ensure continuous grout column from bottom of borehole to surface, avoiding voids and bridging. Grout shall be pumped from bottom up using tremie pipe or equivalent method.

D. Header Piping Installation

1) SUBCONTRACTOR to excavate trenches to connect individual vertical borehole piping to the central manifold. All horizontal piping to be installed with a minimum cover depth of 5’ for frost and mechanical protection.

2) Install all HDPE piping using heat fusion techniques. All joints must be butt fused or electrofused by certified technicians. No mechanical fittings will be allowed below grade unless specified in design documents.

3) Construct or install pre-fabricated manifolds to connect multiple loop circuits, as indicated in construction drawings. Include isolation valves for each loop, purge ports, and thermowells as indicated in drawings and project specifications.

4) SUBCONTRACTOR to pressure test the entire header network after fusion of all joints is complete. Minimum test pressure of 100 psig must be sustained for 1 hour without pressure loss. Results of pressure testing to be submitted to McKinstry.

E. Vault and Building Mechanical System Integration

1) SUBCONTRACTOR to provide vault for header installation as shown in construction drawings and project specifications.

2) Install sleeves or core drill penetrations through vault walls as necessary. Seal penetrations with water-tight, expandable foam sealant or mechanical pipe seals.

3) Install pressure/temperature gauges, isolation valves, and purge ports at points indicated in construction drawings.

4) SUBCONTRACTOR to coordinate transition to interior HVAC piping with McKinstry and other contractors responsible for work inside the building.

(i) SUBCONTRACTOR scope of work to transition to interior HVAC piping and Mechanical Contractor at a distance approximately 5’ from exterior of building.

F. Site Restoration and Demobilization

1) SUBCONTRACTOR to backfill all trenches and borehole caps using native or imported fill. Compact backfill in lifts to restore ground stability and prevent settlement.

2) SUBCONTRACTOR to restore all irrigation piping damaged or removed during excavation and drilling.

(i) All repaired irrigation piping to be pressure tested to ensure leak free installation.

(ii) Irrigation piping and equipment to be tested and witnessed by McKinstry and SLCSD to ensure proper operation.

3) SUBCONTRACTOR shall repair all disturbed surfaces including pavement, sidewalks, and landscaping.

(i) Seed or sod all disturbed turf areas

(ii) Replace all damaged curbs

(iii) Replace any damaged or removed vegetation with similar

4) SUBCONTRACTOR to remove all construction debris, excess materials, containers, and equipment. Sweep paved areas and wash down roadways, if necessary.

5) Restoration Acceptance Criteria:

(i) Grading: All disturbed areas are re-graded to match original contours or as specified in project drawings.

(ii) Compaction: Backfill is compacted in lifts to meet specified density. For purposes of RFP pricing, SUBCONTRACTOR shall assume a compaction specification of 90–95% of maximum dry density per ASTM D698 or project specification. Compaction test results shall be submitted.

(iii) Settlement: No visible settlement or depressions after backfill, monitored for 30 days.

G. Basis of Design

1) SUBCONTRACTOR acknowledges that the project includes materials and equipment specifically identified within the RFP, drawings, specifications, and/or contract scope narrative. Specifically identified materials and equipment shall be considered the Basis of Design and are required without substitution to meet the project's performance and operational requirements.

(i) SUBCONTRACTOR may submit to McKinstry, a substitution request for material and equipment alternatives to the Basis of Design.

(ii) Substitution requests must provide at a minimum the manufacturer, model, performance specifications, and the change in overall bid price compared to the Basis of Design.

(iii) Substitution requests shall not relieve the SUBCONTRACTOR from their responsibility to provide the Basis of Design materials and equipment.

(iv) At its sole discretion, McKinstry shall evaluate substitution requests. If a Substitution Request is granted, McKinstry shall then notify all bidders of the approved alternate.

(v) SUBCONTRACTOR shall be responsible for all changes to supporting systems resulting from acceptance to substitutions H. SUBCONTRACTOR shall furnish, receive, offload, provide crane and rigging, and install new equipment and associated materials as shown.

1) This RFP outlines the scope associated with the installation of the ground heat exchanger. Installation of HVAC equipment and piping inside of the building to be excluded from this RFP. Subcontractor to coordinate connection to building HVAC system with Subcontractor selected for that work.

2) Geothermal SUBCONTRACTOR is responsible for the installation of ground heat exchanger piping. SUBCONTRACTOR to conduct hydrostatic pressure testing to ensure leak free installation as described in scope of work, construction drawings, and project specifications.

3) Provide cleaning and flushing of all newly installed piping prior to startup.

4) Mechanical SUBCONTRACTOR selected for HVAC work inside the building will be responsible for fill of ground heat exchanger piping with appropriate glycol solution. Geothermal SUBCONTRACTOR responding to this RFP to exclude glycol from bids.

5) TAB of ground heat exchanger to be excluded. TAB will be provided by Mechanical HVAC contractor selected for HVAC installation inside building.

I. All systems to be Commissioned by third party commissioning agent

(i) SUBCONTRACTOR shall support commissioning activities as described in project documentation and specifications.

4. STRUCTURAL

A. By others

5. CONTROLS

A. By Others

6. ELECTRICAL

A. By Others

7. DESIGN

A. McKinstry shall be responsible for Mechanical, Geothermal, Structural, and Electrical Design for the scope of work. SUBCONTRACTOR shall work with McKinstry engineers to verify equipment location, mounting and isolation details before installation.

8. COMMISSIONING

A. Functional performance testing (FPT) and system commissioning to be conducted by others.

B. Please refer to the Controls Commissioning Roles and Responsibilities attachment for SUBCONTRACTOR commissioning requirements.

9. TRAINING

A. SUBCONTRACTOR shall provide training, as required, for Scope of Work herein.

10. SUBMITTALS AND SCHEDULING

A. SUBCONTRACTOR is liable for damages to McKinstry for Subcontractor’s sole failure to coordinate schedule and/or meet agreed upon durations and completion dates.

B. SUBCONTRACTOR acknowledges that associated work is taking place on this project site concurrently with this scope.

C. Provide coordination drawings as requested by McKinstry.

D. Provide as-built drawings as requested by McKinstry.

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