For 12 years, Teamster Gary Mecham has been hauling Hanford waste over the same few miles of road from the Columbia River to central Hanford.

He watches for deer and elk, sometimes sees a porcupine and, frequently, a coyote. He knows every bump in the roads, and each of them is felt as his truck bounces along, carrying up to 22 tons of waste.

He and the other Washington Closure Hanford drivers who haul waste to Hanford's central landfill have driven 12 million miles since the Environmental Restoration Disposal Facility opened in 1996. The truckers have had only one at-fault accident.

"That's huge," said Bruce Covert, director of waste operations for Washington Closure Hanford.

Mecham was there at the beginning, the only one of the project's 38 truckers who has been driving the routes from the river since the landfill opened. He's seen plenty of changes as buildings have been torn down and waste dug up along the Columbia River.

And now he's seeing changes at the landfill. Not only is work under way to expand it, but it's going high-tech as the result of problems discovered in early 2007. A former worker made up the results of compaction testing at the landfill and an unrelated malfunction in the water collection system within the landfill's lining went undetected for months.

As Washington Closure Hanford has addressed the problems, it is modernizing the landfill for low-level radioactive waste with equipment not available when it opened.

Next week, two new compactors with cleated rollers will compact waste to make sure that a cap to be placed over the landfill does not develop sink holes. They're equipped with global positioning systems that keep track of how many times each inch of the landfill has been compacted as more waste is added and how much the level changes with each pass.

The new system will replace the former requirement for manual compaction testing.

"No longer will people have to suit up and go into the contaminated area," said Owen Robertson, the project engineer for the Department of Energy.

The new compaction system also will provide the certainty needed to reduce the ratio of soil to debris from 3-to-1 to equal amounts debris and soil. That decreases the possibility that clean soil will have to be used or disposal of debris will have to wait until more contaminated soil is available.

The leachate collection system at the bottom of the lined landfill will be monitored using a new computerized system that tracks the status of the pumping system and levels in the water tanks and sumps. Data is transmitted by radio frequency to the computer, which automatically telephones managers if it detects a problem.

The landfill, which was designed to have 10 disposal cells, is being expanded by subcontractor DelHur Industries to add cells seven and eight. Workers have dug up 600,000 cubic yards of soil and will dig up a total of 1.3 million to finish the two cells in early 2009.

The cells will be 70 feet deep and measure a combined 500 feet by 1,000 feet at their base. That's large enough to hold about 2.8 million tons of material.

The two cells will be the first to include a monitoring system for water beneath its clay base that can be used after the landfill is closed. The system will serve as a check for moisture beneath the clay bottom of the landfill that could indicate contamination is seeping from the landfill long before radionuclides are detected in nearby monitoring wells.

The changes to the landfill come as Washington Closure Hanford is preparing to start accepting more waste from central Hanford in addition to building debris, waste retrieved from old burial grounds and contaminated soil from along Hanford's river corridor.

An estimated 237,000 cubic yards of dirt are expected to be removed from a central Hanford area where animals attracted to radioactive salts are believed to have spread contamination over miles of desert during the Cold War.

Washington Closure has added a scale and is adding six new trucks to be ready for the increased waste shipments to the landfill. Drivers bring in about 150 truckloads of debris a day, which could increase to as much as 250 truckloads.

Already trucks roll to the landfill over two 10-hour shifts four days a week. Mecham, by virtue of seniority, drives 6 a.m. to 4:30 p.m.

"I really like the job," he said. "We know we've actually accomplished something when we look back at the end of the day. ... We're really helping in the cleanup process."