St. Paul Project Utilizes Variety of Products and Services

Hammer & Steel customers and equipment are playing a big part in the ongoing improvements at the Metro Waste Water Treatment Plant in St. Paul, Minn. The $200 million project of St. Paul's Metropolitan Council Environmental Services includes construction of a new 300 dry ton per day solids processing facility, with completion scheduled for the end of 2005.

Veit & Companies of Rogers, Minn., did the site preparation - installing shoring for excavation - from October 2001 to January 2002. The company installed a 185-foot by 370-foot sheet piling cell, using a variety of equipment rented from Hammer & Steel.

Veit tried several hammers before deciding the best one for the job was the PVE 2520 vibratory driver/extractor, which it decided to buy. "We used the PVE 2520 on the majority of sheets," noted Jim Brunkhorst, project manager for Veit. "The output of this unit matched the soils we were working in." The paired 65-foot cold rolled sheet pile was driven to grade through fills to about 20 feet and then through natural till of soft clay to medium clay.

When Veit was looking for the most appropriate hammer, "Todd Maxa [territory manager] and Joe Dittmeier [Hammer & Steel president] were very helpful in putting a variety of solutions in front of us," Brunkhorst said. "And there was no problem in getting the iron to us," he added. "This is a project where we need a variety of equipment. That's where rental comes in handy."

For shorter sheet piles, Veit used an ABI HVR-75 excavator-mounted vibratory driver/extractor mounted on a Caterpillar 330. "It was versatile and allowed us to get in tight areas," Brunkhorst commented. "It worked out well because we needed the crane for the longer sheets. By using the excavator-mounted hammer to drive the smaller sheets, we could dedicate the crane for the higher work."

The biggest challenges on the project, according to Brunkhorst, were working with the 65-foot piles and observing an FAA-imposed ceiling height of 165 feet for a nearby airport. "Because we were threading the long sheets, we were working 150-160 feet up in the air," he said.

On calm days, Veit used man buckets to thread the sheets, but when the wind picked up, the company utilized the Dawson Universal Sheet Piling Threader and Ground Release Shackles from Hammer & Steel. "The threader enabled us to keep working and continue operations," Brunkhorst noted.

The ability to keep the project moving was also important for L.H. Bolduc Co. Inc. of Anoka, Minn., the subcontractor that drove the foundation piles. The company was on site from mid-December 2001 to May 2002, driving 1,958 bearing piles and filling them with concrete. The piling, 12.75" O.D. x .375 wall pipe, was up to 70 feet long. In all, the company drove 118,000 linear feet of pile.

Bolduc used two Delmag D19-42 diesel hammers to drive the piles through soils that were described by Robert Werness, president of Bolduc, as "40 feet of very poor organics and river silt, then sands and colluvial deposits." He continued, "The bearing strata was at 60 feet below existing grade."

The company, which had two piling rigs going at a time on the St. Paul project, already owned a Delmag and purchased another. "They ran well in the various types of driving. We had little or no downtime with the Delmags," Werness said. "That was key. We had a schedule to keep and we finished ahead of schedule - we helped improve the final finishing date for the project."

Veit returned to work on the second phase of the project, a 25-foot deep, 1,200-foot-long tunnel connecting the new solids processing plant to the existing plant. By the end of 2002, the company had driven 575 bearing piles - 70-foot, 12.75" pipe piles - and installed 60-foot paired hot rolled sheet piling. Workers used the Delmag 19-42 for the pipe piles and the PVE 2520 for the sheet piling.

The general contractor for the project is Madsen Johnson Corp. of Hudson, Wis. Both Werness and Brunkhorst said the St. Paul project has been a smooth one for their companies, and both give credit to the equipment.

"So far it's been a successful project," said Brunkhorst. "Having the right equipment was a help." Werness echoed that sentiment. "It was enjoyable. Things went well. We had good relationships on the site and we had the right hammers there."