hawk metheny - batch-bin composting systems on the appalachian trail
TRANSCRIPT
Batch-Bin Composting Systemson the Appalachian Trail
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Exit Strategies ConferenceJuly 30, 2010
Hawk MethenyAppalachian Trail Conservancy
Appalachian Mountain Club
The Appalachian Trail
• 2,179 miles long through 14 states• Designated a National Scenic Trail by the 1968 National
Scenic Trails Act. A unit of the National Park System.• Foot travel only• ~2 million visitors per year• Maintained by the Cooperative Management System .
Federal and state agencies/non-profit/volunteers• 30 Trail Clubs• ~270 designated overnight sites—each with a toilet!
14 States
Six NPS units
Eight National Forests
History of Composting on the A.T.
• Batch-Bin composting systems were developed by AMC on the A.T. in the White Mountains in the mid-1970’s in response to a sharp increase in visitation at remote backcountry campsites. Previous waste management systems were pit toilets, Clivus, Soltran, or airlifting out of waste.
• Earlier systems collected both urine and feces in the same container—required significantly more bark mulch to absorb liquids and properly compost sewage.
• “Beyond-The-Bin (B-T-B) system developed in 1995 with 2 prototypes. Liquid separation is fundamental benefit. Full upgrade by 1998 to 12 systems.
B-T-B overview
Conditions necessary for effective composting
• Oxygen• Heat• Absorption
• Dedicated operator
• Time• * Hardwood Bark*
Hardwood Barkacquired from local lumber mill
50 lb. bags~12 new bags per compost run16-40 bags per site/per season
Bell-Jet Ranger800 lb. external load capacity
(16) 50lb. bags
Essential tools
Urine collection barrel
Pros and Cons
++ Highly effective pathogen
mortality-- over >99.99% reduction
+ Inert, soil-like end product+ Inoffensive outhouse odor+Suitable for high use areas capable of processing
substantial volume in one season
+Visitor education and stewardship opportunity
+ Relatively low tech
-- External mixing agent required- Dedicated personnel- Moderate amount of infrastructure- Moderate initial upfront cost
