Playing to Strengths
Established in 2014, Bourn Environmental is the brainchild of Christopher Perry, a U.S. Army veteran of two tours in Iraq and one in Afghanistan, and holder of a BS in environmental science from West Point and an MS in environmental planning and management from Johns Hopkins University. After first working for a larger firm doing similar work, striking out on his own made perfect sense to Perry.
“Even when I was much younger, I always loved nature and wildlife,” he said. “My experience in the Army was as a combat engineer so, when I separated, someone suggested that I should pair up my two strengths — engineering and love of the environment — by doing wetlands mitigation. So here we are today with a crew of nearly 20, capabilities in stormwater management, living shorelines, streams — really anything having to do with wetlands — and some exciting work ahead.”
The work in which Perry and his team are currently involved, calls for the remediation of more than three miles of a Piney Run tributary near the village of Sykesville, Maryland. He said the project — being done for the State to earn credits under Clean Water Act provisions — is an effort to correct decades of stormwater mismanagement.
“As a company, the vast majority of the problems we see involve serious stream bed erosion, largely the result of development in the region,” he said. “Having all that impervious surface increases the likelihood of flash flooding, which yields massive amounts of sediment along with nutrients like phosphorus, nitrogen, etc. — all headed downstream and eventually to the Bay. Piney Run was a perfect example of that.”
Change of Tactics
Since its inception, Bourn Environmental had performed its work using traditional techniques: largely relying on survey stakes and a laser level for layout, and a small excavator to handle the earthmoving facets of the job. However, a visit to a training session in Wyoming provided the impetus Perry needed to take his operation to the next level.
“While at those sessions, some of the larger environmental remediation companies from North Carolina were singing the praises of GPS technology, raving about how much it sped up their production,” he said. “I thought the time had come give it a try, and having the Piney Run job coming up, it seemed that this would be the ideal opportunity to do so.”
With that in mind, Perry contacted the team at JESCO, Inc., the local Topcon dealer, from whom they’d been renting their machine, levels, etc. Although Bourn’s initial interest was in a dozer that featured GNSS-based machine control, the JESCO team felt it important to let Perry know of some other options available to enhance their operation.
“We knew we wanted a dozer with machine control because of all the time we felt it could save us in doing our flood-plain work,” said Perry. “However, JESCO was great in starting the conversation about what GPS in an excavator could do for us. They brought a machine equipped with a Topcon X-53i system out for us to demo and our guys loved it to the point of arguing over who got to use it. We placed our order for a second machine on the spot. Today, we have that same system on a pair of John Deere 245G excavators and can’t imagine doing another project without it.”
After the delivery, according to Brett Howett, JESCO’s territory manager, his company gave Bourn their initial training on all the machine control systems and will follow up as needed and as they continue to become adept with it. “We’ve found that, most often, we give the customer the basics and as they start using it, their proficiency goes way up — and that’s definitely been the case with the Bourn team. Right now, their guys can probably run a rover better than any of us.”
To appreciate the value of a GNSS solution to Bourn’s operation, one need first understand what it is they do to remediate a stream like Piney Run. There, what was once a meandering, at-grade stream, now has sections, which feature 8-10 feet banks due to relentless scouring from flash storms. Under normal conditions, the stream would simply overflow and empty onto the adjacent flood plain. That’s no longer possible.
“So, at Piney Run, we have literally buried the old channel and are carving a new one through the flood plain,” said Perry. “We’ve raised the stream bed and lowered the plain so that water can empty onto it more easily like it was meant to do. In addition, the project’s engineering firm has designed a series of structures throughout the course of the project that will affect the direction and velocity of the stream in different ways. Our excavator operators have really taken to the GPS in making those structures — which are made of either wood or imbricated stone — happen. If they are wood, they are massive logs or root wads; if they are stone, they can be anything from small aggregate, to huge boulders stacked atop each other. Regardless of the material, however, we have to maintain tolerances of .2 throughout the project.”
In the case of the larger boulders, which generally weigh 3-4 tons, the excavators must dig deep into the stream’s subbase so that the top of the structure can hold that grade and create a pool after it. Bourn’s operators used the strengths of the GNSS solution to make that part of the job fast and accurate.
“It’s hard to get huge boulders to stack perfectly and then try to do so in a circle for a step-pool, but still make it all look uniform,” said Steve Griffin, Bourn’s Foreman. “That’s why digging down to a specific grade for two different rocks each time allows us to keep a constant elevation on the top. Our operators would measure two rocks that stacked well on top of each other, subtract that from final grade on the system to get that number on the screen, and then simply dig to that subgrade. It’s fast and reliable and has worked out great.”