4. Best Building Project – Specialty Contractor (Under $2 Million)

Specialty Contractor: Intermountain Electric, Inc.

Project: Green Mountain Pump Station (GMPS) Electrical

Intermountain Electric (IME) was hired for the project’s switchyard removal and replacement of

existing motor control center (MCC) lineup for 3 medium-voltage pumps. Green Mountain

Pump Station (GMPS) is an unmanned pump station facility owned by Denver Water, located in

Lakewood, Colorado. GMPS services approximately 9,480 residential customers and 760

commercial taps.

IME’s scope of work included removing and disposing of the existing equipment; and electrical

furnishings, installation and commissioning of the new equipment. The project included conduit

duct bank, transformers, medium voltage switchgear, new MCC lineup, PLC, fire alarm system,

and security system. IME provided new medium voltage from Xcel cabinet to new switchyard.

The switchyard replacement included a 15K metal clad switch, (2) 2,000Kva transformer 15K-

4160 substation and a walk-in switchgear section. Then all fed to the building to feed the new

MCC lineup to feed the pumps.

Biggest challenge: logistics for conduit duct bank – 36 conduits underground, gathering into a

pump gallery, and direct burial to the exposed conduit system.

There was a slim 3-ft. clearance to work around the header pipe, 5–tier rack that the 36 conduits

fanned out upon. IME had to transition those stacked conduits to fan out, so that they could

elevate to the MCC level above. IME had about 30-40 ft to make that transition to fan those

conduits out. The majority of the GRC conduit bending was fabricated in IME’s fabrication shop

with high precision. Which, given the restraints of the project area, would have made it

extremely difficult to bend and thread all of that work on-site. So we had to measure it, bend it,

prefabricate it all off site and essentially bring it on site to build the duct bank. We left the last

and pivotal piece, the adjustable piece, as the final transition from conduit to a PT nipple. This

decision would give us some flexibility to increase or decrease that nipple length to make sure

we actually hit our tolerances.

There was a high level of BIM and coordination. Before we could start any of the work, we had

to demo part of the existing facility and the existing switch yard. There were no As-Built

drawings, so we had to shoot point with Trimble to create drawings that didn’t previously exist

for a starting point to our BIM efforts.

Overcoming schedule: IME was not able to get started on its scope of work on time because of

issues with easements and utilities not allowing site shut down the existing service per the

original schedule. IME was scheduled to do the duct bank work in end of October, but

excavation didn’t start until mid-December. We reached substantial completion on the project,

and the pumps were up and running by the end of March, so minus the delay, and the weeks of

the commissioning, actual work was compressed into about 13 weeks with about 75% on site and

25% in our BIM and Fabrication shop. We made up the front end of the schedule by heavily

loading the project with additional manpower.

Major obstacles:

Duct bank and trying to figure out how to transition 36 conduits from 5-levels of racking to the

same vertical plane and fan them out, turn them up into the wall, using offsets, kicks, and various

transitions in order to get them up to the same level. The tricky part is where they come in from

the duct bank to their respective destinations so they’re not saddling and jumping conduit.

That’s where BIM came in handy. We modeled up the conduits and fanned them out and if we

saw a conflict then swapped conduits until they nested correctly. This took precision modeling

and layout and precision bending. There was no room for trial and error. We had to build it in the

virtual environment and trust that we got it right in the virtual space and then upon fabrication.

Lack of existing information in the systems. For example, there was an existing HV generator

that the current set of drawings did not accurately represent the control schematics. The older

equipment had to be integrated into the new equipment. The facility unmanned and everything

was automated through their Programmable Logic Controllers (PLC’s) from remote

headquarters. We had to tie-back in the existing generator and a couple different systems. The

control schematics regarding their existing generator was our biggest issue with respect to

lacking existing information.

Partnering – client required that we provide a detailed ‘step-by-step’ commissioning plan.

Part of the commissioning process required IME to essentially energize virtually every

component through each and every point of its relay or protective schemes in sequence -

then demonstrate to the client that the equipment and installation works as designed. IME

partnered with its sister company Dashiell. They wrote the commissioning documents for

the project and test procedures. They were critical in meeting the deadline.

Safety – equipment better and safer, we had a specific safety plan. IME worked 10,141

without a recordable incident. Green Building techniques included in-shop recycling,

smaller footprint at the site. Kitted and packaged delivery allowed a safer work

environment.

Commissioning was efficient and smooth – we did a full ‘dry-run’ pre-commissioning

exercise using the commissioning checklist to ensure when the client would join the

actual commissioning process, we were 100 percent confident that they would get

nothing but full reliability, removed of any and all bugs and kinks. We spent two weeks,

and 1 week on the actual commissioning with Denver Water. IME had 18 different

components to commission - including the PLC’s. (Amwest was the system integrator)