Foundation Drilling Ensures
Frequently, the workers on the side of bridges, overpasses, highways or soundwalls are ignored or unnoticed by motorists.
These workers, called foundation drillers, are an obscure but key specialty within the Caltrans Division of Structural Foundations. Their job is to test drill through existing or planned roads, highways, bridges, overpasses and foundations.
Drilling is tough, arduous work that requires being on the road almost non-stop, working mostly outside up to 10 hours a day for up to six days a week. Working in crews of three to four, California’s foundation drillers ensure the strength and integrity of 15,200 miles of public thoroughfares, including 22,000 bridges and overpasses.
When floating barges to access pillars, rappelling steep mountainsides to board a bridge, airlifting heavy equipment via helicopter into remote areas or logging up to 50,000 miles annually per crew-cab truck, the foundation driller’s mission is to ensure safety for 33 million residents – and millions of free-spending tourists. The drilling crews must comply with many state and federal safety and environmental regulations protecting people, places and property.
“If we’re not doing the job right, roads would crumble, fall or fail in some way,” says Norm Webb, who was a drilling technician for Local 3 from 1986 to 1999 and then became a state foundation driller for Unit 12.
There were only 18 drillers statewide in 1997 but because of increased transportation demands, there now are 47.
Prior to ConstructionIt is through test drilling that engineers and planners assess the strength, size, scope and appropriateness of the foundation for a new or soon-to-be remodeled project. After construction, drilling is part of the preparations for renovation, replacement or seismic retrofitting.
Drillers provide the engineering data and parameters for the design of bridge foundations, roadway sections, retaining walls, soundwalls, cut slopes and landslides.
“We’re the ones who drill holes in the ground, take samples and turn them in to the lab, which determines the depth of new foundations,” Webb explained. “The results depend on the density of the soil and other concerns, like an earthquake (threat) or flood or whatever.
“When the life span of a bridge goes out, and they’re thinking about replacing it, we do a study to (help) figure out the costs. We account for what type of foundation, how deep it’s going to go – that kind of thing.”
Webb’s supervisor, Ed Leivas, agrees. As chief of drilling services, Leivas has overall responsibility for his 10 to 13 three- and four-person crews that include truck and trailer-mounted drills, several all-terrain drill rigs and smaller specialty rigs that can be broken down and reassembled for remote locations.
Because of the valuable background, training and experience offered by Local 3, many drillers cited their skills as former operating engineers as a key element in their success.
Leivas’ crews are dispatched statewide as needed, and are at risk daily from motorists who might not give them a break and from on-the-job perils like working closely with heavy, high-speed equipment. They regularly attend mandatory safety days, and each fall in the Sierra Nevada there are week-long “driller academies,” which are a mixture of classroom and hands-on training.
“Our guys do the best job,” Leivas says. “The quality and amount of their work is way up there. I’m really proud of them.”
The Need Is NowRenovation, replacement or retrofitting is needed now more than ever because much of the Golden State’s infrastructure is heavily tarnished.
Many of the state’s aging highways, bridges and overpasses are nearing the end of their designed life span or are inadequate in a state where population – and vehicle numbers – have grown exponentially since the 1950s.
Substantial state and federal funding has followed that growth, as has Gov. Gray Davis’ $1 billion-plus annual increase in highway projects. But in the view of many Caltrans officials, those commitments are not enough to keep up with demand in a fast-growing state with aging infrastructure.
At the same time, changing requirements brought on by improved technology, an increased emphasis on earthquake safety and a soaring population have had a direct impact on the division’s workload.
For example, foundation drillers used to bore down an average of 70 feet to assess the density, condition and type of supporting material. Today, foundation drillers often must bore 120 feet to 150 feet, reflecting improvements in technology and advanced knowledge of earthquake preparedness, according to Laurel S. Jensen, senior engineering geologist for the foundation drillers who has been in charge of most of the hiring since 1997.
“Foundation drilling is an art,” Jensen says about the mechanical and computer skills drillers must possess. “Not every driller can do this.” The job is demanding technically and personally. “They use laptops for downloading info from their (motel) rooms when on the road and to communicate with maintenance stations or the home shop.”
Soil conditions can vary widely site to site. Skill, technique and intuition are required to efficiently retrieve the proper sample, says Jan Rutenbergs, a senior engineering geologist. Because samples must be kept five years in case questions arise, great care is taken to ensure their accuracy.
These demands make it necessary for every worker to be able do anyone else’s job on a given day, according to Carl Boling, senior foundation driller. “The good thing about here is there’s 47 of us and you can put any one of them on any piece of 90 different pieces of equipment and they’ll know what to do,” Boling says. “That shows what their qualifications are. They’re a great bunch of guys, and it takes all of us to make things happen.”