The 850-foot Trails Arch Bridge crosses the Colorado River, connecting Topock, AZ, and Needles, CA. Built in 1916, it was once part of U.S. Route 66 but now carries a natural gas pipeline owned by PG&E and Kinder Morgan. The Trails Arch Bridge was named to the National Register of Historic Places in 1988.
Safely remove potentially hazardous lead paint while providing full environmental containment and allowing the owners to maintain production. Brock was contracted to abate and contain low-level paint on the span in order to avoid potential contamination of the river and surrounding environment.
Our crews needed to build access suspended across a public waterway to perform the work, which included blasting and removing more than 1 million pounds of waste. Additional project challenges included wind and live load considerations as scaffold placement was designed and the need for 40,000 CFM units to clean the air and remove product.
The project was executed in three phases, with containment barrier walls separating the phases.
To perform the abatement, Brock crews first had to provide access over 150,000 square feet of structural steel and piping. We used a standard “ring-lock” system scaffold that weighed more than 1.3 million pounds. Although scaffold crews gained initial access to the bridge from the California side, where the first 285 feet of scaffold were installed, the blasting and paint activity was conducted from the Arizona side. It took more than 850 feet of piping and hose to reach the work area.
Abrasive blasting was used to remove the lead-contaminated paint. Timing was critical to limit exposure during days when temperatures exceeded 120 degrees.
By utilizing Blastox, a calcium silicate-based material that encapsulates the lead, we were able to make the spent abrasives and paint chips non-hazardous for proper disposal. We disposed of more than 1 million pounds of non-hazardous waste.
After abatement and preparation, we recoated the bridge, using a total of 3000 gallons of primer, intermediate and finish products. This was a very detailed process requiring us to get behind and between hundreds of nuts, bolts and seams. The use of containment barriers allowed blasting activities to proceed while scaffold was being installed. Clean air tunnels required during phases two and three allowed work activities on both ends of the bridge without affecting blasting and coatings production.
The execution of this project presented a number of unusual challenges, including days where temperatures reached 120 degrees outside and 130 degrees inside the containment area. The project required more than 30 semi loads of scaffold weighing 1.3 million pounds that were transported manually in carts across the bridge runway.
In addition, we were working in two different states, and traveling from one side of the project to another required a 20 minute drive along rural roads. Most of the property on the Arizona side is privately owned, and developing good relationships with landowners resulted in unprecedented cooperation from them.
In January 2013, we received the George Campbell Award for outstanding achievement in the completion of difficult or complex industrial or commercial coatings projects from SSPC: The Society for Protective Coatings.
Established in 2007, the George Campbell Award honors owners and contractors who overcame issues such as extreme environmental conditions, strict time constraints, limited access or high-traffic areas, complex structural components or coordination with multiple trades and subcontractors.