Oroville >> Nearly 80 days after winning the bid to fix the disastrous Oroville Dam spillways, the contractor Kiewit offered the Chico Enterprise-Record and Oroville Mercury-Register Friday a close-up view of construction efforts.

The best way to describe the site is perhaps “organized chaos,” with over 400 employees and equipment like 60-ton trucks zipping about. There were massive projects ongoing in each direction, as the contractor is racing to reconstruct the bulk of the structure by a Nov. 1 deadline.

Crossing over the top of the dam, the top of the spillway is visible. There was little activity there Friday, as the state Department of Water Resources wants to hold off on major repairs because the rock foundation is better than that lower in the structure. Some of it will be patched, but DWR does not plan to rebuild it until next season.

The top of the upper chute was mainly being used as a holding place for materials and equipment like mounds of rebar which will eventually be layered into concrete for the spillway.

Further down, trucks were removing dirt in order to clean the bedrock, preparing to line it with leveling concrete, a temporary means of covering and protecting the surface. Eventually permanent structural concrete will go in, said Jeff Petersen, project manager and vice president of Kiewit’s Northern California branch. Petersen has been with the employee-owned company for 29 years.

Clearing efforts were further along from the lower to middle sections of the spillway. Craftspeople worked their way down, cleaning the bedrock and waiting for leveling concrete to arrive at the higher portions, where it would be placed several feet high, Petersen said.

Construction workers refer to the rock exposed there as “moonscape rock,” apt for the gray and rugged landscape where the spillway used to be. After areas of the site are power washed, geological technicians come and give the OK before leveling concrete is poured, he said. Roller-compacted concrete is only going into the middle chute areas where there are extremely large holes because it is the quickest and most affordable method, Petersen said.

At the bottom of the emergency spillway, crews drilled test sections for the cutoff wall, which will go between 35 to 65 feet below ground, depending upon the rock quality, said Erin Mellon with the Natural Resources Agency.

Simultaneous with clearing and testing projects, material going into the new structure this season is being prepared. Rocks go through a crushing process and the aggregate into the roller-compacted concrete batch plant. Coming from the crumbling spillway, this is all recycled material from the site.

There is a second batch plant for Portland cement concrete. As not enough materials for this aggregate could be found at the dam, Kiewit purchased them from a local company, Matthews Readymix.

Keeping cool

To cope with the extreme heat this summer, employees are briefed on safety precautions to avoid heat-related incidents before their shifts and cooling stations are set up around the site. Concrete also has to be cooled, as the material needs to be maintained at a certain temperature in order for it to set correctly. Usually, adding ice to the mixture and misting it is enough, though there is also liquid nitrogen in case the other methods don’t get the job done.

With 100 degree plus temperatures, no one has been rushed to the hospital, Petersen said. Kiewit is avoiding putting workers out between 12 p.m. to 6 p.m. There was recently one incident which was not heat-related, he said. An employee with one of the subcontractors broke his hand in a welding accident.

In employees’ eyes

Leo Gilbert, a member of the Craft Voice in Safety Group, said he quit a better paying job for a chance to work at the dam with Kiewit.

“I knew they treat their guys well, top notch,” Gilbert said. “(It’s a) high profile job.”

In the group, he is one of the people workers can bring their safety concerns to. They may be less likely to speak up to a supervisor, he explained.

Also on board to be a part of history is Lonnie Morelock, an operations manager for the contractor. Morelock is now a third-generation worker at the Oroville Dam, as his father, grandfather and uncle worked on the dam prior to its construction, all Operating Engineers Local 3 members. In town to work at the dam, his father met his mother in Paradise.

“But not for the Oroville Dam, I wouldn’t be here!” he said.

Morelock was set to follow in his father and grandfather’s footsteps from an early age, with his father bringing him to sites starting at the age of 4, he said. He likened working with Kiewit on the dam to being on an Olympic team.

“It’s an amazing project to be a part of,” Morelock said. “These opportunities in your career are few and far between.”