A special concrete pouring and cooling method reduced the impact on the environment.

Fossil fi nd

Prior to construction, the entire right-of-way was evaluated for historical signifi cance. Along the State Highway 130 route, crews found a prehistoric site where more than 75 archaeological features were investigated.

The site contained the skeleton of a bison, and 31 materials that dated back to between 400 B.C. and 1200 A.D., including stone cooking hearths, carbonized plants, arrows and dart points. Materials were carefully dug up, documented and curated with the Texas Historical Commission.

through the site to determine the necessary steps, such as saving trees or implementing erosion control measures. “We had a project archaeologist, a water quality specialist and an endangered species expert on call at all times, in addition to the normal every day staff,” said Jon Geiselbrecht, environmental coordinator for the Turnpike. And, the team adopted even more stringent rules than were required. For example, they adopted a tougher water quality standard than the national standard, even though the construction wasn’t in the aquifer area. These standards regulated everything from preventive

From the beginning, the project

team adopted an aggressive and proactive stance on environmental issues. TxDOT, Lone Star Infrastructure, and Hicks and Company co-developed an award- winning environmental management system for the State Highway 130 project. The creation of the system, an uncommon practice for most construction projects, meant numerous staff and specialists were always available to examine any environmental issue.

For example, after each parcel of land was acquired for the project, the environmental staff and the construction supervisor would walk

34 | Green & Clean

measures to discharge allowances to spill clean up.

Construction techniques

During construction, crews used a concrete pouring and cooling technique that simplifi ed installation, strengthened the concrete and lessened the environmental impact. Typically, concrete is cooled using ice. Ice can usually only cool concrete by about 20 degrees. When temperatures are warm, ice is not a practical or simple solution. Crews used liquid nitrogen to lower the temperature of the fresh concrete, and at a much faster rate. Studies have shown cooler fresh concrete results in

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stronger concrete.

Wildlife and wetland mitigation

To offset the impact on wetlands and wildlife in the area, TxDOT worked with the Army Corps of Engineers to create 175 acres of new and preserved wetlands on a 265-acre tract.

TxDOT is partnering with Caldwell County and the City of Lockhart to create a public wildlife area with nature trails. This will be the fi rst county park in Caldwell County. “Instead of us buying the 265 acres and just fencing it off, we said let’s open it up to the public so they can get some benefi t from it,” Geiselbrecht said. As part of the development, TxDOT planted 70,000 trees and created ponds and wildlife habitats. The park will open when the newly planted trees are well established and growing. Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36