SSC Completes Unique Project for Army Corps of Engineers

In June 2011, SSC was given the opportunity to contract with Sybrant Construction, a local General Contractor, to perform work on a tunnel for the Army Corps of Engineers. Sybrant is a frequent contractor on military construction projects and SSC was honored to be selected as a part of their subcontractor team to successfully complete this project.

The project was a continuation of one started earlier in the year by another out of state tunneling contractor. Sybrant had first constructed an entry shaft 10′ in diameter and 40′ deep. Using this shaft, a 180′ tunnel had been constructed and then abandoned for the Army to use for communication and detection testing. Following this initial testing, the Army required the tunnel to be extended to a finished length of 300′, and SSC was brought in to construct this additional 120′ of tunnel.


The excavation was rectangular, 5 ½’ wide and 7 ½’ tall, working inside of a tunnel shield and excavating out 3′ in front of the shield. Once the area in front of the shield was excavated, the shield was jacked forward hydraulically, and in the space left behind a wooden cribbing system was constructed.

The ceiling and walls of the tunnel were built using 8″x8″ timbers on the walls and 8″ x 10″ timbers on the ceiling (ribs), and filled in between with 3′ x 6′ x 32″ lagging sets. The finished product was a 5′ tall by 3′ wide wooden framed tunnel. Along the bottom of the completed tunnel was a track system, used to push a muck cart in and out of the tunnel to carry supplies in and spoils out.


The process was repeated over and over (40 times total) until the full 120′ of additional tunnel was excavated and framed out. Each time the shield was pushed and a set was built, new hose would have to be added for the ventilation system, compressed air for the jackhammers used for excavating and hydraulics for the jacks on the tunnel shield. The entire distance also had to be lighted, and new track had to be added for the cart to travel on. On average the SSC crew dug 5′ each day and built 2 sets of cribbing. This equates into 9 yards of dirt being excavated and removed each day, totaling 600,000 lbs of earth being moved by hand over the course of the project.

The power behind this job was almost all manual labor performed by SSC’s crew. The excavation was done utilizing jackhammers – being held out ahead and overhead – a very physically demanding assignment. The earth being excavated was extremely dense – almost a caliche-type soil.


This made for slow and hard digging. Once the earth was hammered loose, it had to be shoveled out of the new excavation and into the muck cart. Each time the cart was filled with soil, weighing approximately 2300 lbs, it had to be pushed, by hand, through the 5′ tall tunnel out to the shaft, where it was lifted out and dumped by a crane. When it was time to build a set of the cribbing, the timbers and lumber were loaded into the cart and those materials were pushed by hand back to the face of the excavation.

The fact that SSC’s 5 man crew was able to withstand these extreme physical challenges and complete this work in 33 days is an almost Herculean accomplishment. Compounded on top of the physical demands were challenges with the tunnel shield that had been constructed by the prior tunneling contractor. It was a non-steerable shield which made keeping on line and grade difficult.


SSC’s team was able to maintain near perfect line and grade, however, and were able to correct issues inherited on the first 180’section of tunnel. The finished project was constructed exactly to the Army Corps’ specifications and will be used for years to come by the various divisions of the military for testing to improve border security and operations in the Middle East. The overwhelming success of this project can be fully attributed to the can-do attitude of SSC’s team.

What Our Clients Say:

  • “Just wanted to say thank you for the safety culture your company has. It’s a breath of fresh air to see other companies embracing being safe. I sat in on your crews’ safety meeting this morning prior to the start of their work on Ray Rd. “

    Scott Nunemaker – Vice President, RCCM

  • “Kuddos to your guys. Not once has any of your foreman’s EVER put up a fuss when I’ve asked them to work a little late. Response is always “whatever you want and we’ll stay as long as you need us to.” I really appreciate all the hard work they do for me. Thank you sir.”

    Travis Barrick – Field Supervisor, Felix Construction

  • “A big thank you to SSC for jumping on this quickly as they did to help the team get this information so quickly. It’s much appreciated and was pretty impressive to see 5 separate potholing crews descend upon Rio Salado the way they did today!”

    Christopher Laute, Resident Engineer, Valley Metro

  • We’ve used SSC for a number of years and I’ve been very pleased. Thanks and keep up the great work.

    Dave Klann, Staff Engineer, Mactec

  • SSC did a great job. Their assistance during pre-construction was greatly appreciated and differentiated them from the competition. Keep doing what you do best!

    Jim Drago, Sundt Construction

  • I called with short notice to some work and SSC responded immediately. In this market, dollars seem to control everything and quality of people and work seem to have diminished. The professionalism and hard work of your crew takes me back to when people knew what they were doing and cared. Intelligent guys that work […]

    Lonnie Ferguson, Project Manager, Construction 70

  • As a civil engineering consultant, I usually recommend your services but rarely use them with the exception being vacuum excavating. I have attended your seminars in the past and find them very helpful. I recommend continuing the education to make designers better. If we understand and know how to specify your service, we are more […]

    Bill Gasque, Sr. Civil Engineer, Dowl HKM

  • SSC handled the project perfectly even went above to schedule directly with the gas company, made my job easier.

    Tony Smith, Owner, Western Underground

  • You and your staff are always responsive to our needs and make sure you clearly understand the scope of the work in advance, so there are no surprises. I really appreciate that attitude.

    Michael Rhodes, Civil Engineer, Gila River Indian Community

  • Overall a good company. Very professional in approach and execution of work. Courtesy and respect shown by all personnel, a welcome rarity in the business. Keep doing what you’re doing, and thank you.

    M. Gartner, Project Manager, Sybrant Construction

  • We have been using your company’s services for about 3 years now. I have never heard a negative comment. Bringing Curtis on board is a definite plus as far as I am concerned. He keeps me informed about the work that I have done and he is very through and dependable.

    David Cross, Utility Coordinator, MCDOT

  • Your field crew did a great job!

    Nick Nikrant, Project Manager, Builders Guild

  • Crew was courteous & helpful.

    Jayde Bullard, Project Manager, Caljet of America, LLC.

  • This is the second time working with this foreman. Will request him again. Easy to work with.

    David Willett, Aero Automatic Sprinkler Co.

  • Superb foreman…Exceptional!

    Curtis Briggs, Shea Homes

  • Great work! SSC was timely, responsive and professional. I would use them again.

    Stewart Vaghti, Project Engineer, Gannett Fleming, Inc.

  • I have always had good and quick service from SSC.

    Sally Raymer, Sundt Construction

  • Arvid was very accommodating in getting crew onsite within 2 hours of my call.

    Dennis Sime, Project Superintendent, Hunter Contracting

  • First I want to express once again how impressed I am with you and your support group. You are all “top notch.” Yes the job went well and I appreciate your help. It really made a huge difference on such a critical facility. I still can’t believe (even though I saw it with my own […]

    David McKinley, VFC-Arizona

  • Great service on short notice. Thanks!

    Richard Komzelman, Carson Construction

  • The entire SSC crew was extremely professional and flexible. All of your company’s efforts are greatly appreciated and you will be our boring subcontractor on any future projects.

    Ben Myers, Project Manager, GRG Construction

  • Your team made this challenging casing push a success.

    Michael Fossett, Project Manager, SDB Inc.

  • Extensive knowledge of the local soil conditions coupled with their proven skills has insured that every job is completed within our schedule and budget. We’ve worked with SSC for many years and always found them to more than equal our high required standards and able to complete any task.

    Brian Chavez, Chief Estimator/Project Manager, Tyers Contracting

  • I would like to thank you for your prompt response to our urgent need for your services. The men you sent did a fantastic and quick bore. We do so appreciate your company for that. Thanks!

    Patricia Riggs, Town of Gila Bend

  • Our job was especially challenging. The SSC team worked six days, around the clock and the testimony to the success of their efforts is that the general public never knew they were here. An additional thanks to SSC for their professional courtesy. In our industry, it is something I do not encounter often enough.

    Chris McCoy, Superintendent, Gilbane Building Company

  • Your project manpower’s knowledge, attitude, safety and work ethic are outstanding!

    Mike Levi, Estimator/Project Manager, Holloman Corporation