ELECTRICAL UPGRADES AT MILITARY OCEAN TERMINAL CONCORD (MOTCO)

  • Client: US Army Corps of Engineers
  • Location: Concord, CA
  • Date: 2015
  • Contract #: W941238-11-D-0031-0002
  • Value: $3,134,594

Cerrudo Services, Inc. designed and constructed the electrical upgrades for the military ammunition distribution post Military Ocean Terminal Concord (MOTCO).  MOTCO’s mission is to receive ammunition from ships at piers on the Sacramento River and distribute the ammunition to various Army posts via rail.

The project scope of work consisted of five parts:  1) upgrade of the PG&E Bay Point Feed substation; 2) upgrade of Pier 3 electrical distribution; 3) replace pole type transformers with pad mount transformers; 4) replace overhead power and communication distribution with a new underground system; and 5) provide pad-mounted primary voltage switches/junction boxes on 5 KV circuit along a section of White Road.

The design included electrical design drawings, calculations and specifications.  Design elements included calculations for electrical load, roadway lighting foot candles, voltage drop and arc flash.  Brokaw provided a layout for underground alignment indicating trenching population and location of underground structures, typical trench cross-sections, utility conflicts, and placement of hand holes and vaults.  Replacement requirements of Bay Point Feed fuse cut-outs were developed.  Layouts were provided for pole to underground transition at riser locations, pad mounted transformer and primary sectionalizing switch equipment and secondary service panel replacement.  Single line diagrams for electrical, telecom and signal distribution systems were provided.

There was a “moderate to high” risk of encountering MEC (munitions and explosives of concern) in the area of underground work.  Once the alignment was approved, the installation of underground work began.  The UXO (unexploded ordnance) team was on-site to provide UXO construction support during excavation and backfill operations.  The trench alignment was marked and staked.  After trenching, PVC conduit supports were installed for the high voltage duct bank locations.  After low voltage conduits were installed, the trench was backfilled and compacted.  After inspection and approval of the high voltage duct bank conduit installation, concrete was poured around duct bank conduits.  Once the concrete had cured, the trench was backfilled to the top of the existing grade.

After the conduits were in place, underground conductor was pulled for the primary power, fiber optic, telecommunications and CATV systems.  This work included pulling new conductor into the underground conduit, constructing pads for new transformers and switches, installation and testing of new equipment and panels and connections for all of the systems.  We coordinated with PG&E to upgrade the new Bay Point Feed by installation of a new pole top air switch on an existing pole.

Cerrudo upgraded the electrical distribution at Piers 3 and 4 with a new dry type pad mounted transformer installed in the same location as the demolished transformers at buildings A-22 and A-23.  New 800 amp panel boards at buildings A-22 and A-23 were installed.  We installed a new secondary feeder conduit and conductor between the new transformers and panel boards were installed, and terminated and energized existing circuits to new panel boards.  Pads were constructed and new transformers installed at four locations, connected to existing primary and secondary feeders.  Four new fused pad mounted switches along the White Road primary feeders were installed.  Work included new pads, cutting into the existing duct bank and conductor and installation of the switches.  New underground primary power wiring and equipment were provided to replace the demolished overhead system.