The primary purpose for Yo2’s existence in ’87 was to build a septic system for the Vogelsang High Sierra Camp (VHSC).
http://www.yosemitepark.com/Vogelsang-High-Sierra-Camp.aspx
Yosemite has a ring of five primitive lodges strung around the high country. Each lodge is about 10 miles or so from the next one in the ring. Starting out from Yosemite Valley and going up through Little Yosemite Valley behind Half Dome, the first lodge one comes to is Merced Lake. The next one in line is Vogelsang, which is also the highest of the lodges at 10,100 feet. The Yosemite concessioner runs saddle trips around this loop. Ten miles makes a good ride for one day, leaving the guests plenty of time to relax at each gorgeous spot. The entire loop can be completed in one week.
I call them ‘lodges’ instead of ‘camps’ because of the civilized amenities each one has. Guests sleep in tent cabins. A tent cabin has a wood floor and canvas walls and roof. There is a kitchen and a dining hall…also in a tent cabin. Some of the lodges have showers. Vogelsang does not have that particular luxury. There are toilets…which brings us to our project. Over the years, the septic system at VHSC failed and the effluent found its way down to Fletcher Creek. The locals started calling it ‘Flusher Creek’.
The first attempted solution was to build a set of Clivus Multrum composting toilets. They actually worked the way they were supposed to, reducing human waste to compost with no odor.
http://en.wikipedia.org/wiki/Clivus_Multrum
They only had one problem. The compost from the toilets cannot be used in the backcountry. It has to be flown out for proper disposal. Helicopters are expensive. Somebody decided that in the long run, it would be cheaper to build an old fashioned septic system with a vault and a leach field. At 10,000 feet. On top of slick rock. (OK…I might be editorializing too soon here.)
To make room for the cinder block vault, a hole needed to be blasted into the bedrock big enough to fit the vault. We showed up in the middle of this project. They had already blasted once and we showed up just in time for the second blast. While the NPS workers started laying cinder blocks for the vault, we Corpsmembers started digging the trench for the 4” PVC pipe that was going to connect the vault to the leach field.
The leach field. Our nemesis for the summer.
One of the problems inherent in backcountry septic systems is the lack of any soil depth. For a leach field to work, effluent needs to be able to percolate down through the soil or small rocks. At 10,000 feet, the soil is very thin. The effluent would just flow across the top of the slick rock and remain a health hazard.
Engineers ran the numbers and calculated that enough percolation could be obtained by creating a mound of crushed rock 100 feet long by 100 feet wide and 18 inches deep. This was about 555 cubic yards of crushed fill, or about enough to fill 55 large dump trucks. It was also critical that the crushed rock have the dimensions of 2”x2”x6”.
And guess how all of that rock was going to get crushed? With sledge hammers (or double jacks, as trail crews call them) swung by members of Yo2, including our attached NPS sponsors.
We could see now the problem that our dwindling crew numbers presented. We had already lost manpower and skill. Yo2 had been promoted during recruitment as a construction project. We had been told before we even applied that this crew would be building a backcountry sewer system instead of most of the trails that Backcountry crews normally worked. Every Backcountry applicant was asked if he/she was willing to work on this crew on this project. Every one of us had volunteered for this. Three Corpsmembers had been recruited specifically for their construction skills. Two of them had quit in Wawona. Wayne Vanderleest, from Placer Energy Center, was the only technically trained Corpsmember left on the crew. And crushing that much fill would have been hard enough with the full crew of 17 that we had started the season with. We were down to 13 crewmembers.
This was going to be a long project.
Three Years With the C's 