This document summarizes different types of remote toilets and their performance. It finds that pit toilets and composting toilets often fail to properly treat and manage human waste, posing risks to human and environmental health. Urine-diverting vermicomposting toilets have much lower operation and maintenance costs than other options, with fewer health exposures and better waste treatment. The document recommends source-separating urine and feces for remote sites and looking to local decomposer organisms to naturally process separated human waste over long time periods without adding bulking agents. Urine-diverting toilets offer a better paradigm for sustainable remote sanitation.

1. HOW REMOTE TOILETS
WORK (OR FAIL TO)
And what they should really be doing
Geoff Hill, PhD
Sustainable Summits Conference
Golden, CO

2. Waterless Toilet Overview Comparison
Elbow Lake, AB
Campground, open 3 months per year
Use/yr: 5000
2 stall - 2 Composting Toilets
Annual O&M cost: $2660
O&M Freq: weekly
Cost per use: $0.53
OSHA Exposure Events/yr: 33
Material removal: every year (dump)
Faverges, France
Road Side, open 12 months per year
Use/yr: 20000
1 Stall – Urine Diverting + Vermicomposting
Annual O&M cost: $700
O&M Freq: yearly
Cost per use: $0.035
OSHA Exposure Events/yr: 3
Material Removal: every 10-20 years (dump)

3. Outline
• Waste Paradigm
• Compost – what it actually is
• Remote Site Challenges
• Types, Objectives, Evaluation of Remote Toilets
• Human Waste Composition & Production
• Source Separation
• Urine Diversion
• Performance of Urine Diversion vermicomposting toilets
• Future Direction

4. Flush Toilet
• Homes in the Western world
• Water (cheap / limitless)
• Power (cheap / limitless)
• Onsite labor (cheap, home owner)
• Nutrients needs (garden, lawn)
• We FLUSH it away
• Waste Management Paradigm
• Toilet #1 invention for human health
• Water as vehicle – everything removed at WWTP

5. Compost from biosolids in USA
• Biosolids extracted from WWTP – burned, land applied, or
composted
• Public operations are held to EPA 503 rules, thermophilic
engineered process for degrading and sanitizing waste
• 5 turns in 15 days, >55C, fecal coliform testing to assure process,
• Very rigorous and challenging
• Done at centralized facilities
• Still very difficult to make profitable and worthwhile

6. Remote sites
• No power / solar power
• No water
• Limited / expensive labor
• Cold
• No use for nutrients or organic
matter

7. Types of Toilets at Remote Sites
• Pit
• Dig hole (6-10’ deep), fill up, cap, dig another.
• Composting
• Buy unit, users add wood, ‘service’ weekly, blackwater leaches, dump
solids onsite yearly (or pack-out)
• Vault (concrete or plastic barrel)
• Buy precast unit, pump yearly, remove to WWTP
• Incinerating (very few – private)
• Urine Diverting Vermicomposting (France)
• Not covering dispersed
• Pack-out
• Cat hole

8. Objective of These Toilets
• Pit
• Lowest cost regardless of human health & environment
• Composting
• Make compost, regardless of O&M cost & safety
• Vault (concrete or plastic barrel)
• Least environmental impact, safety, O&M cost
• UDVCT
• Lowest life cycle cost O&M, acceptable environmental impact, and
high health & safety standard

9. Pit Toilet In Ground Water: World Heritage
Site, BC

10. Pits
• Pits can be found years later – no
decay
• Many toilets dug into ground water
• With 1m unsaturated soil
• Viral pathogens can travel 3000m
• Hepatitis A, Polio, Astrovirus, Calcivirus,
Rotavirus, Norwalk, Coxsackievirus,
Echovirus
Sources:
WHO Funded: “Guidelines for Assessing the Risk to Groundwater from On-Site Sanitation”, British Geological Survey
Moore, C., 2010. Institute of Environmental Science and Research (N.Z.) Staff. Guidelines for separation distances based
on virus transport between on-site domestic wastewater systems and wells. ESR Communicable Disease Centre, Porirua,
New Zealand.

11. Pits
• Treatment paradigm
• Not effective
• Dumps in our parks?
• Waste Management Paradigm
• Not safe
• Virus travel very far
• Very hard to detect (few labs culture viruses)
• NPS – should all be replaced
• With…..

12. Composting toilets
• Don’t compost shit at home…
• Why compost shit in the woods?
• Tried to failure dozens –
hundreds of times

13. Composting Toilet Photo Tour

29. Composting toilets (CTs): a misnomer
• PhD + 5 peer review publications
• 4 brands, 12 sites, 16 chambers, 100+
samples
• 0/16 chambers pass NSF Standard 41
• 0/16 processes meet EPA 503 regulations
• None heat up more than 10C above ambient
• 0/100 samples meet definition of compost
• Stability, maturity, smell
• Raw fecal matter no different from CT end-
product (E.coli, volatile solids, stability)
• All continuous flow
• Effective residence time: 1-2 days
6yr old ‘compost’

30. 2 outcomes
• Ammonification toilet
• Primarily urine – ammonia & pH escalate – inhibits all life
• Not effective enough to reliably sanitize
• Many campgrounds and trailheads
• Pathogen brew pot
• Primarily fecal matter
• UBC CK Choi – Flagship of composting toilets, maintained by paid
personnel every day.
• >100,000 E.coli in 5yr old material (E.coli breeding ground)

31. Composting Toilets as Waste
Management (typical 3000 user site)
• $2665/yr to maintain
• 33 occupational exposure events / yr (face close to
fecal)
• Effective?

32. Vault Toilets - Barrel
• True waste management perspective
• Terribly expensive and hazardous to operate
• $0.30 to $1.00 per use
• Requires an operator to change barrels

33. Human Waste Production / Composition
• Urine
• 160-200ml per use
• 80% of plant nutrients (NPK)
• Zero heavy metals
• Zero pathogens
• Self sanitizing (storage)
• Flows by gravity
• Fecal matter
• 80-100g per use
• 20% of plant nutrients
• 100% of heavy metals
• 100% of pathogens (106-8bacteria,
helminth, viral, protozoan)
• Doesn’t flow

34. Source Separation
• For maximum value & least cost ‘waste management’
• Waste Management BMP
• Lets apply to wilderness waste
• Human waste = urine + fecal (2:1)

35. Urine Diversion Retrofits (2)
• Ecovita 501 Privy
• Clogged within a week of installation

36. Urine Diverting Vermicomposting
(UDVCT)
• Ecosphere Technologies & Ecodomeo (France)
• No bulking agent

37. UDVCT
End-Product Waste Management
Stable – Very Stable O&M costs/yr = $273
No odor Exposure events/yr = 3
<200 CFU/g E.coli Dry matter reduction = 40%
Lots of trash Emptied every 10-20 years

38. UDVCT vs CT
UDVCT CT Comparison
O&M costs/yr = $273 $2665 10x
Exposure events/yr 3 33 10x
Dry matter reduction -40% +300% Almost 10x
Disposal Emptied every
10-20 years
Every 6mo – 2
yrs
5-20x
E.Coli <200CFU/g 104-106 CFU/g 100x lower

39. North American Implications
• Step 1: divert urine
• Gravity manage to septic field 66% of daily mass
• Step 2: don’t add bulking agent
• Step 3: look and see what’s eating local horse manure
(naturally source separated) and put it into fecal matter &
toilet paper
• Step 4: don’t touch the poo, leave it for as long as
possible
• Step 5: budget a decadal line item for removal and
disposal

40. Slugs in the Pacific Northwest

41. Step 1: Divert Urine (the hard step)
• Behavior
• Ecovita seat – private only
• Mechanical (Toilet Tech Solutions)

42. TTS Below-the-Floor
Glacier Bay National Park, AK

43. TTS Behind-the-Wall
Glacier Bay National Park, AK
Neat and Cool, Squamish Smoke Bluffs, B.C.
Sponsored by MEC, District of Squamish, and
Climate action network.
$4000 plus or minus