Significant Fossil Find Unearthed in Colorado by Gould Construction

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Joe Enzer, the owner's representative for Snowmass Water and Sanitation, and Gould Construction employees Kent Olson and Jesse Stele hold mastodon tusks uncovered last fall at teh reservoir site near Snowmass, Colorado.
Mark Gould, at left, gets a behind-the-scenes tour at the Denver Museum of Nature and Science from Chief Curator Kirk Johnson.
An excavation project near Snowmass Village last fall by Gould Construction Inc. took on mammoth significance when a dozer operator uncovered a cache of ice age bones.

An excavation project near Snowmass Village last fall by Gould Construction Inc. took on mammoth significance when a dozer operator uncovered a cache of ice age bones.

It is considered one of the most important fossil discoveries in Colorado history according to scientists with the Denver Museum of Nature and Science, although the first reaction of Mark Gould (CivEngr '81, MS '82), the company's president and CEO, was concern about keeping the construction job on schedule.

"The first thing that went through my mind," says Gould, "was, oh no, the job's going to shut down."

Roughly 600 countable bones have been recovered so far, from Columbian mammoths and American mastodons to ice age bison and deer, as well as numerous frogs, snakes, and salamanders. A variety of well-preserved plants, insects, and shelled creatures were also recovered. The bones are estimated to be between 45,000 and 130,000 years old; testing is continuing.

Once Gould realized the magnitude of the once-in-a-lifetime discovery, he became excited about the find and has since developed a passion for paleontology. At the time, however, he had to balance his contractual commitment to finish the job with accommodating the scientists' requirements as they recovered the fossils.

Gould Construction was under contract with Snowmass Water and Sanitation to excavate the foundation for a new dam at Ziegler Reservoir, which meant removing roughly 76,000 yards of dirt from the site. There were multiple layers of sediment in the footprint of the dam, including five to 15 feet of silt, five feet of peat moss, and five feet of clay.

The excavation job, which began Sept. 15, was proceeding as planned until Oct. 14 when the first mammoth bones were uncovered by a dozer operating in the peat layer of what had once been an ancient mountain lake.

The discovery was made by Jesse Steele, a heavy-equipment operator with Gould Construction, who saw what looked like a cow's rib bone. Taking a closer look in the dirt around the dozer, workers found more large fossils, including the jawbone of a mammoth. Steele and Kent Olson, a site supervisor, conducted an online search for mammoth bone photos, which matched the bones they had uncovered.

"Bones the size of your leg popped out," says Gould. "When peat is excavated, it's like a feathery down material. As the dozer blade was going over the bones, the peat kept them fluffed up like a pillow of down, which kept the bones from being too badly fractured by the dozer blade."

A Colorado state law basically states that if fossils are found on property owned by the state or one of its districts (which Snowmass Water and Sanitation is), then the fossils are the property of the state of Colorado. The state's agent, which in this case was the Denver Museum of Nature and Science, was tasked with recovering the bones. A frenzy of phone calls later, Kirk Johnson, chief curator and vice president for research and collection at the museum, was reached.

"Single mammoth finds are relatively common, but multiples are not," says Johnson. "In the initial stages of excavation, we didn't know if what we'd found was important or not. It quickly became clear that this site was significant. When we realized that this was a real site and not a single occurrence and we saw all the bones coming up, it became an adrenaline sprint.

"We dropped what we were doing and ran up there," he says. "We flew in a number of world experts and what came out of that was that it's a unique site for a number of reasons."

In addition to the numerous animals found, two significant finds were a Jefferson's ground sloth and a massive ice age bison. The sloth is the first of its species found in Colorado and it was found at the highest elevation of any sloth found in North America. The bison find was impressive due to its size. From tip to tip, the bison's horns measured an astonishing seven feet wide.

During the hubbub of discovery, Gould Construction was allowed to keep working, although the work proceeded much differently than before. Each time a dozer was deployed to dig, paleontologists walked on each side of the machine looking for fossils.

"The state of Colorado has established an awesome fossil site that wouldn't have come to light if it hadn't been for Gould Construction and its employees and the folks at Snowmass Water and Sanitation," says Johnson.

Paleontologists scrambled to dig out as much as possible before winter weather set in, while Gould Construction hurried to finish its work. Despite the interruption, Gould Construction was able to meet its deadline by working 10 hours a day, six days a week. The Denver Museum of Nature and Science was able to deploy more than 40 trained volunteers within days of the discovery and their efforts logged the 3,600 man-hours of excavation in the 18-day window between October 29 and November 15.

"Mother Nature gave us extra days of good weather to find more animals and to finish our contract," says Gould. "We initially had a loss of productivity, but we were able to catch up and get our work done on time."

After receiving a bachelor's degree in 1981 and a master's degree in 1982 in civil engineering, Gould joined Gould Construction Inc., a family-owned operation in Glenwood Springs, Colorado, and serves as president and CEO of the company. His two sons are CU graduates and now work for the company. Mark Jr. has a business degree and is vice president of operations. Evan, who received a communication degree, is safety director and heads up the trucking department. Gould's daughter, Megan, is studying mechanical engineering at Cornell University.

Gould Construction received a Build America Award from the Associated General Contractors of America. The award was given for Grizzly Creek diversion and pipeline construction in a remote, environmentally sensitive area of the White River National Forest. Gould assembled a design team that included classmates W. Scott McNary (CivEngr '81, MS '84) of McNary Bergeron and Associates, and Frank Harrison (MS CivEngr '84) with Michael W. West and Associates.

All construction was accomplished with helicopter support. Construction crews camped on site throughout the project to minimize impact. It's all part of the comprehensive approach Gould Construction takes, both in meeting construction requirements of a project and being responsible environmental stewards.

On May 14, scientists will return to the Snowmass site hoping to uncover more fossils. Although Gould Construction's job is finished at that site, Gould will be keeping an eye on what they find.

"It's possible this find will rewrite paleontology books, as well as paleobotany and geology books," says Gould. "For generations, my family will get to go to the museum and see the animals we dug up in Snowmass. It was really neat to be involved in this."

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