Monday, July 26, 2010

Scenic job sites, part two...

This photo of a spyder excavator working on a slope west of the Golden Gate Bridge is one of my favorites, and I didn't even shoot it. The project was to remove two cliff-side landfills from the Presidio of San Francisco. We used spyder excavators, conveyors and a bucket brigade of long-stick excavators to remove 73,000 tons of debris. The job was a lot of fun, although the 30 mph winds that came up nearly every afternoon made dust control an occasional problem. We uncovered all kinds of junk including several pieces of post-civil war unexploded ordnance. The possibility of lurking explosives kept everyone on their toes, lest they lose their toes, or worse. We also learned about the differences between the military's approach to ordnance disposal and the SFPD's Bomb Squad approach...but that's a post for another day.

Monday, July 12, 2010

Digging where the scenery is really nice

AIS speicalizes in difficult jobs.  The down side is the jobs are, well, difficult.  One of the upsides is that we work in a lot of scenic areas.  Here's a picture from a landslide repair we completed near Mariposa, California.  This picture shows a spyder excavator working to clear landslide debris from a slope high above Highway 49 and the Merced River.  The picture doesn't show it, but the temperature was routinely over 100 degrees in the canyon.  The cool river was very inviting, but we had a rule - no swimming until after qutting time.

Wednesday, July 7, 2010

It was a long haul, but worth it in the end.

AIS recently completed a big chunk of dredging work for CH2MHILL in the Spring Creek Arm of Keswick Reservoir.  Our dredge Corrin removed approximately 150,000 cubic yards of contaminated sediment from this tributary of the Sacramento River.  CH2MHILL and the US EPA have been working together to clean up acid mine drainage from the former Iron Mountain Mine.  AIS worked closely with AHTNA Government Services on this job.  They operated the mud treatment facility.  Dredging work goes on 24 hours a day and seven days a week, so it is very tiring.  Most of us plan to rest for about a year after this one.