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Gas Project Stages
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CONSTRUCTION PHASE
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DESCRIPTION
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TYPICAL DURATION
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Site Mobilization
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Contractor moves equipment and material near the construction area or to their storage yard. Contractor marks the boundaries of the area for underground Service Alert (USA).
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1 - 2 working days
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USA / Survey
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Underground Service Alert (USA) and City Survey Crew marks out existing utilities and proposed gas main alignment on the street pavement with spray paint.
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2 - 5 working days
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Sawcutting
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The Contractor sawcuts existing pavement as marked by the survey crew.
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1 - 3 working days
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Excavation
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The Contractor removes pavement and excavates soil to prepare for installation of a new gas main and services.
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1-3 working days
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New Gas Main, Services Installation, and Existing Services Reconnection
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The Contractor installs the new polyethylene gas main by directional boring methods and either installs new or reconnects existing services.
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2-6 working days
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New gas main and service air pressure test
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The Contractor performs air pressure tests on the new gas main and services before connecting them.
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The gas main and services are pressurized with air at 100 PSIG for 24 hours.
For a typical city block: 2 - 5 working days.
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Backfilling
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Contractor fills and compacts the ground openings with backfill material as the new main is installed.
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Performed concurrently with the new main and services installation and connection
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Install Temporary Pavement or "Cutback"
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Temporary cold asphalt mix is placed on the backfilled area to temporarily restore the roadway service. If your street is concrete, steel plates will be placed on top of the trench in order for the concrete base to cure, prior to final restoration.
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Performed concurrently with the new main and service installation, connection, and backfill
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Purging the new gas main and services and tie-in into the system
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The City crews purge air from the new main and services and connect the main into the existing gas system.
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3-5 days per block
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Final Pavement Restoration
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The Contractor removes temporary asphalt pavement, steel plates, and restores pavement and all surface improvements to the preconstruction condition
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1-3 days per block
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Modification of house gas plumbing systems
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If gas meter has been relocated, the Contractor modifies and tests the customer’s house gas plumbing system.
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4 hours to 1 working day
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Surface restoration
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The Contractor restores all existing improvements and landscaping at each location to the preconstruction condition.
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After completing the plumbing work at each house location
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Service Transfer
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The City crews transfers each building’s individual gas supply from the old to the new gas system.
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Gas service interruption due to transfer should not exceed 8 hours.
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Pilot Relighting
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The City customer service representatives relight pilots at each house that was transferred from the old to the new gas systems.
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Before 5 p.m. on the day of the service interruption or after hours upon contact from customer. Please call (650) 329-2413 or (650) 329-2579.
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Final cleaning
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The Contractor sweeps the street affected by the project and removes USA markings.
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1-2 days per block
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