Unsuitable Soil

Keith Brubacher

Keith A. Brubacher

Unsuitable Soil – two words developers and site contractors spend a lot of time discussing in many contract negotiations. Thorough pre-project soil analysis, a realistic plan and clear communication are the three keys to handling the associated risks while retaining trust.

Using diverse skills, the Brubacher team did just that on a recent project you'll read about next. The site was previously disturbed, interwoven with soil layers of varying suitability. During the bid stage, Brubacher's estimating team built a digital model depicting what geo-technical probes revealed. Using this to base the bid upon, a digital terrain model (DTM) was created by the Brubacher Survey dept. to guide GPS-equipped earthmoving machines. Upon excavation, additional areas of non-structural material were discovered in between areas the client probed. This required additional changes to earthwork balance and design models.

Using the original 3D model for comparison, the project team worked with the client to determine a mutually acceptable way of tracking and compensation for the additional scope. Coordination between the site engineer along with Brubacher's estimator & quantity take-off tech ensured that cut/fill amounts balanced.

Bringing the process full-circle, GPS-equipped dozers and an excavator followed undulating profiles of various soil layers. Unsuitable material was placed in non-structural areas of the site while suitable material was compacted in structural areas. Borrow pits maximized availability of good soil and served as a receptacle for poor soil. All of this was accomplished over winter while protecting the precious stable fill material from unnecessary exposure to frost and water puddles.

To the average passerby the project looked like a normal earthmoving project... big equipment moving dirt from here to there. To the equipment operator it looked like a spider web of detailed layers and grade lines. To the experienced construction professional, it was a well-orchestrated plan come to life. To me the project showcased the value of Brubacher's integrated team solving challenges, leveraging technology and communicating well. Most importantly... to the client it was a trusted business partner sharing Insight. On Site to reduce stress and manage risk to ensure a successful project.