Rock-Water-Sewers

October 2012, Vol. 67 No. 10

Vincent Rice has considerable experience planning underground installation jobs and is proud of his company’s successful pre-planning project track record. Rice, founder and president of Aaron Enterprises, York, PA, is extremely knowledgeable in the various disciplines of trenchless technology, and has been providing personalized trenchless installation services since 1976. The company focuses on auger boring, tunneling and directional drilling, and is known within their south central Pennsylvania trade territory as “rock specialists.”

With more than 60 employees currently on staff, Aaron Enterprises has enjoyed steady growth over the years and earned the respect of numerous engineering firms that often turn to Rice and his team of installation professionals to determine the feasibility and most effective approach for completing trenchless projects. Having encountered nearly every challenge imaginable within the realm of the underground world, even Rice could not have anticipated the additional influx of water created by an angry Hurricane Irene as she invaded the inland Pennsylvania jobsite where his crews were tackling an intricate sewer installation project.

Aaron Enterprises served as general contractor for the gravity sewer job that was initiated as a precursor to a road construction project that required existing sewer mains be relocated due to a design change in the approach and exit ramps of Benjamin Franklin Hwy. The project -- situated on the outskirts of Pottstown, Montgomery County, PA -- had its fair share of inherent challenges from the onset. At .22 percent minimum slope, grade tolerance was critical. Additionally, the lines were to be positioned at a relatively aggressive depth, often exceeding 20 feet. Groundwater, originating from the shallow water table of the nearby Schuylkill River, was also a concern.

“Maintaining the gradient was absolutely critical,” says Rice. “The carrier pipe of the sewer was specified as 24-inch iron mainline and the casing pipe was only 36-inches in diameter, so we didn’t have much tolerance. The other concern was the close proximity of the existing sewer. Alignment was critical because of the new highway changes, At many points along the bore path, the new line was within five inches of the existing sewer.”

And then, there was the rock.