Locals refer to it as “The Missing Link,” a 1.65-mile stretch in the foothills of the Great Smoky Mountains that for years has proved an obstacle to completing a key segment of the envisioned 72-mile national scenic road called the Foothills Parkway.

Previous attempts to construct the gap in the Parkway were abandoned before completion, as ravines and rocky ridges created engineering obstacles.

Beginning in 2010, the Federal Highway Administration's Eastern Federal Lands Highway Division partnering with the National Park Service, contracted The Lane Construction Corporation to design and construct the remaining $48.5 million portion of The Missing Link. A crew of skilled operators led by Lane’s construction manager, Tom Meador, is carving out a .9 mile, two-lane roadway along the western flank of Rocky Mountain.  The remaining portion of The Missing Link which included four bridges and connecting road segments, was completed by other contractors.

Lane’s portion of the project calls for construction of five bridges. It also includes building retaining walls as high as 48 feet and making cuts into the mountainside that can reach depths of 90 feet. The width of the construction limits for this two-lane road ranges from 100-120 feet with elevation changes as much as 100 feet within those limits. The project from end to end has elevation changes in excess of 300 feet. Due to the remote location, Lane operates its own concrete plant onsite. 

Labor intensive

Given the higher elevation and narrow construction corridor, normal production rates are drastically reduced. “Excavated material is handled many times over as part of a concerted effort to minimize any environmental impacts,” Meador says.

One aspect of the project involves blasting Cambrian Era rock, consisting of dense conglomerates and some sandstone. As part of a painstaking process, the rock is crushed and reused as structural fill. It starts off with a cubic yard of material being blasted loose, loaded into off-road trucks, and reloaded into on-road trucks. These trucks take the material down the Parkway to a crusher, where materials are crushed and stockpiled for later use and the hauling cycle is reversed.

“For access to a lot of the project, we only have a 20-foot wide pioneer road, which is a one-lane road,” Meador says. “So, the reason it takes that long is that one operation commencing could stop another because of the limited access. We use many spotters, going up and down the mountain, so that we can safely pass each other with our equipment and vehicles.”

Counting on Caterpillar

Lane Construction uses Cat® equipment to complete the challenging task of pioneering a road on the side of a mountain. Four Cat 336E Hydraulic Excavators play key roles in carving out the right of way.

“When it comes to our choice of Cat equipment, it’s really a matter of reliability,” Meador says. “We’re on top of a mountain, but we’re really on an island, because if we have an issue up here, the mountain is very unforgiving. If you have an issue, it’s going to multiply because of the terrain that we have. So having dependable equipment is vital. And we know that we can count on our Cat machines.”

“I HAVE RUN ALL THE EXCAVATORS—ALL TYPES AND ALL SIZES—AND THIS ONE, POUND FOR POUND, IS ACTUALLY THE CADILLAC OF EXCAVATORS.”

In November 2012, Lane took over all the civil construction on the job. This included all of the excavation, roadwork and retaining wall construction with the company’s own crews and equipment.

“That’s when we decided to purchase and rent equipment from Stowers Machinery and hire local people,” Meador says. “Getting the equipment from Stowers is the easy part. Finding talented operators to come up here and run it was our bigger challenge.”

“Stowers is very responsive—anything we need, they will come up and help us,” Meador adds. “They have been very helpful in providing us with parts and consumable items.”

Standing with a sweeping mountain vista over his shoulder, Lane equipment operator Greg Holsinger said the Cat 336E Hydraulic Excavator is the best he has ever run.

“I have run all the excavators—all types and all sizes—and this one, pound for pound, is actually the Cadillac of excavators,” Holsinger said. “It’s strong, it’s got a good base to it, and it’s got a good feel. The Eco-Mode saves a lot of fuel, and it doesn’t affect the performance of the machine one bit, other than saving fuel. I can’t tell whether it’s on high horsepower or in Eco-Mode, there’s not one bit of difference in the performance.”

Environmental considerations

In the course of their work, Lane crews take great care not to damage the surrounding environment. The company can incur penalties if a falling rock damages a tree or a limb.

“The environmental aspects are very important on this job, and we are careful to follow all of the guidelines from the Tennessee Department of Environment and Conservation,” Meador says.

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Considerable effort goes into containing blasted and excavated rock. A prime concern for both Lane and the National Park Service is acidic runoff from certain rock formations. Lane is responsible for identifying the pyritic rock, containing it, and treating it. Lane is practicing both identification and treatment to minimize impacts to the Park’s ecosystem.

To construct the bridges, Lane builds them into the mountainside in top-down fashion. Crews build a trestle across the span of the bridge, and then go back and build the bridge itself. “This way, the only disturbance to the ground is the actual footprint of the temporary foundations for the trestle that goes across,” Meador says, thus keeping the natural vegetation intact to the extent possible.

Safety concerns

Given the unique setting, maintaining adequate safety is a constant focus, Meador says. Lane has 50 employees working at the jobsite, as well as 20 to 25 workers through its subcontractors.

Lane holds daily safety briefings, first meeting as a group. Job superintendents also hold individual briefings, called a job hazard analysis, based on the actual tasks assigned to crew members that day.

“When we cut down rock on slopes, we will go back with the hammer and re-scale it to make sure there are no loose rocks up there,” Meador says. “So, everything is about safety. It goes back to making sure that we have spotters when needed. You can tell by the equipment that we have up here that our operators are very skilled, and they need to be.

“This is the type of project where ‘slow and steady’ wins the race,” Meador says. “We are committed to completing the project and bridging the gap on this key section of the Parkway.”