OPERATION AND MAINTENANCE
MANUAL FOR CRAG CAMP
COMPOSTING TOILET
Model : Bio-Sun Systems Inc. WRS 1000 PS
Compiled by : Paul Lachapelle, Sept. 1995
Toilet Installed : July, 1995
TABLE OF CONTENTS
I BACKGROUND
II HOW THE COMPOSTER WORKS
A) Composting Overview
B) The Bio-Sun System
- Electrical System
- Liquids
- Solids
III MAINTENANCE
A) Work Schedule
- Daily or As Needed
- Weekly
- Monthly
- Twice/Year
- Yearly
B) Other Responsibilities
C) Tools, Supplies Needed
IV PROBLEMS / RECOMMENDATIONS
V WARRANTY INFORMATION
APPENDIX
This composting toilet operates on the principle that the
human waste within the tank, if
given enough air and time, will
decompose into a soil-like material. Natural oxygen-using
bacteria
(aerobes) consume harmful organisms (pathogens) within the waste. The
pathogens within the human waste are also eliminated over time when
exposed to oxygen
or as a result of the competition between
organisms, natural antibiotics, the loss of nutrients
and heat. The
total volume of the pile is reduced as some of the mass is converted to
carbon dioxide and water vapor by the aerobes.
The aim of
composting technology is to optimize conditions for microbial activity.
The
essential ingredients of a compost pile are organic material,
microorganisms, moisture,
oxygen and heat. The process of
transforming raw waste into finished compost results
primarily from
natural soil microorganisms such as bacteria, fungi and actinomycetes.
Soil
invertebrates such as springtails, mites, millipedes and beetles
also contribute to waste
decomposition. Adding wood chips increases
the amount of organic material or carbon,
absorbs moisture and odors
and provides air space and structure within the pile. This
carbon
source, preferably hardwood shavings, must be added periodically in order
to
support aerobic decomposition. The compost pile must also be
mixed to increase aeration.
B) The Bio-Sun System
Note: the
front of the tank refers to tank access door and exhaust vent area. (see
Appendix,
figures 2 - 14)
The structure was built by John
Tremblay and Pat Hackett and opened in July 1995. The
tank measures
51" high x 71" wide x 101" long and has a total internal area of 1000
gallons
(130 cubic foot). The tank has a total liquid capacity of
126 gallons before an overflow
situation occurs. This Bio-Sun toilet
differs from other composting systems because of the
high air-flow
volume and ratio of air interfacing with the waste surface. The
temperatures
reached within the waste pile are in the mesophilic
range (50_ F to 120_ F). This differs
from the batch or bin
composting technique, which is a thermophilic (120_ F+) method.
This
technique is widely used at facilities maintained by the Green Mountain
Club and
Appalachian Mountain Club. The aim of thermophilic
composting, which requires frequent
mixing and high wood chip input,
is to kill pathogens quickly and with hot temperatures. In
comparison, mesophilic composting is a long-term method which can take
years to
effectively reduce or eliminate pathogens within the waste.
Mesophilic composting differs
from thermophilic composting because
the mixing process is not as often and the amount of
wood chips added
is much lower. Wood chips must be added to the tank at a ratio of one
full 8 oz. coffee can per 25 uses. The wood chips should be
deposited through the toilet
seat. In order to maintain a consistent
supply of carbon added into the tank, only the
caretaker should add
the wood chips. While the caretaker may add organic food scraps,
guests should not be allowed to put food into the system.
The toilet
is situated over a sealed container. Inside the chimney is a fan that is
powered
by a solar (photovoltaic) panel. The fan draws air through
the system. The waste is
suspended on a perforated liner and air is
able to circulate above and below the waste pile.
The air enters the tank through the toilet seat. The air is then drawn
into the primary air
inlet tube at the back of the tank. The air
also travels along the sides of the tank and
underneath the waste
pile into the perforated inlet tube running the length of the tank. The
air passes the centrifuge vaporizer unit in the base of the exhaust
vent then past the fan
and back outside. The box around the tank is
stained black to increase heat absorption. A
thermometer has been
mounted inside the tank to monitor the ambient air temperature. A
second thermometer is situated in the waste pile to record temperatures
within the pile.
 the high liquid light and 2) the
array voltage. In full sun, the volt <BR> meter should read as
follows:<BR>
everything off - 37 v<BR>
fan only (full) - 31 v<BR>
fan & vaporizer - 30 v<BR>
vaporizer only - 36 v<BR> The system is equipped with a fan to
increase the amount of air flowing through the <BR> compost tank. The fan
is located directly below the ventilator. The fan will operate year <BR>
round, regardless of how low the temperature gets. However, a thermostat
(TH-1) will shut-<BR> down the entire system, including the fan, if the
temperature reaches 165_ F. The fan <BR> speed control is located on the
right side of the control panel and should be left on full. The <BR> fan
speed will vary depending on the amount of available sunlight. A fire
extinguisher (non-<BR> electrical) has been mounted on the inside of the
tank and contains a fusible link. The link <BR> will activate the fire
extinguisher when the temperature inside the tank exceeds 165_ F.<BR>
<p>
<U>Liquids<BR>
<p>
</U>Unlike many composting toilet systems, it is all right
for users to urinate into this system. <BR> This system is designed to
increase the evaporation rate of liquids. The four factors that <BR>
affect the evaporation of liquids are 1) the relative humidity of the air,
2) the temperature of <BR> the ambient air, 3) the evacuation/replacement
of the ambient air and 4) the efficiency of <BR> the liquid surface
interface with the evacuation/replacement air flow stream.<BR> The
centrifuge vaporizer will activate if the accumulation of liquid is faster
than the <BR> evaporation rate. The vaporizer activates when the liquid
level raises the black ball <BR> attached to a steel rod and turns on the
float switch (FS-1). The vaporizer will operate only <BR> when there is
direct sunlight. When there is sufficient voltage, the relay that is
mounted <BR> below FS-1 will open the connection between the photovoltaic
panel and the vaporizer. <BR> When activated, the vaporizer motor spins a
hollow cone which draws the liquid upwards. <BR> As the liquid spins, it
changes to a mist thereby increasing its evaporation rate. The <BR>
vaporizer will run until the liquid level decreases, the ball drops and
the float switch is <BR> returned to the off position. To avoid damaging
the vaporizer, a thermostat (TH-2) will <BR> deactivate the vaporizer when
the temperature goes below 36_ F. The vaporizer will <BR> reactivate when
the temperature returns to 36_ F or higher. Liquid evaporation within the
<BR> tank occurs while temperatures are below freezing due to sublimation,
the process by <BR> which solids change to a gas without becoming a
liquid. <BR> When 72 gallons of liquid has accumulated, the float switch
(FS-2) will illuminate the high <BR> liquid light in the control panel.
The tank can hold an additional 70 gallons before an <BR> overflow
situation occurs. A ruler has been attached to the bulkhead divider in
order to <BR> determine liquid level changes. A faucet attached to a hose
has been installed at the <BR> access door area of the tank. If an
overflow situation is expected, the caretaker can drain <BR> liquids into
a provided bucket. The caretaker should mix bleach (store-bought brand)
with <BR> the liquid. The ratio should be 1 ounce bleach to 1 gallon
liquid. The bucket should be <BR> mixed with a stick and then stored
overnight. Some foaming will occur and should be <BR> expected. The
bucket should be emptied into a nearby hole. The hole should be <BR>
approximately 2 feet deep and away from the camp and water supplies.<BR>
<p>
<U>Solids<BR> </U>
<p>
The compost pile must be thoroughly mixed once a month
during the warm summer months <BR> of June through September. If a cone
of fresh waste and wood chips builds underneath the <BR> toilet chute, the
caretaker should use a garden hoe to push the fresh waste towards the <BR>
back of the tank. This should be done regardless of the temperature.
Older compost <BR> should be kept towards the front. Fresh waste should
not come in contact with the older <BR> compost. After several years, a
portion of the contents can be removed and disposed of <BR> on-site,
spread thinly on the forest floor in the early summer and away from the
camp or <BR> water supplies. Finished compost should be removed from the
front portion of the tank <BR> only. The manufacturer recommends that
only 2 cubic feet of finished compost be removed <BR> from the front of
the tank (directly behind the dividing bulkhead). Do not remove garbage
<BR> that has been deposited into the tank. Let the garbage complete the
cycle with the compost <BR> and dispose of off USFS land. <BR>
<p>
<CENTER>III
<B><U>MAINTENANCE<BR> </CENTER></B></U>A) <B>Work Schedule<BR>
<p>
</B>Abbreviations:<BR>
Y/R = To be done year round<BR>
40+ = To be done when temperatures are above 40_ F<BR> (See Appendix,
figure 15 for this section)<BR> <U>Daily or as needed<BR> </U>Y/R <B>Add
wood chips</B> according to usage. The manufacturer recommends 2 lbs/100
<BR> uses (one full 8 oz. coffee can/ 25 uses). DO NOT over-add wood
chips. A handful <BR> or two of dry forest duff can be added periodically
to the pile to increase the soil <BR> invertebrate population.<BR> Y/R<B>
Sweep</B> outhouse floor.<BR> Y/R<B> Monitor waste pile and tank</B>
conditions for odor, flies, and garbage (do not remove <BR> contaminated
garbage but rather try to apprehend the party to educate).<BR>
<p>
<U>Weekly<BR> </U>Y/R<B> Check control panel</B> above toilet seat in
daylight hours to see if 1) the high liquid <BR> level light is
illuminated and 2) the array voltage gauge is reading between 0 and 37
<BR> volts (depending on the amount of light). The array voltage gauge
indicates that the <BR> photovoltaic panel is producing electricity. If
the high liquid light is illuminated, open <BR> the access door and check
liquid level in the tank. If liquids are above the faucet <BR> outlet,
open the faucet and drain off excess liquids into one of the supplied <BR>
containers. Dispose of liquids as outlined in the
Problems/Recommendations <BR> section.<BR> 40+<B> Check liquid level</B>
by opening access door and observing area in front of bulkhead <BR>
divider. <B>Special attention should be paid during spring melt
period.<BR>
<p>
</B><U>Monthly<BR> </U>40+<B> Test high liquid level light</B>
(during daylight hours) by pressing the red test button <BR> located on
the control panel door. This indicates that the system is working
properly <BR> and that the vaporizer will activate when the float switch
(FS-1) is turned on.<BR> <U>Monthly</U> (continued)<BR> 40+<B> Test the
Vaporizer</B> (during daylight hours with full sunlight) by gently lifting
up on <BR> the black ball attached to the float switch (FS-1). The float
switch may already be <BR> activated. When activated, the vaporizer will
spin the liquid and will be audible from <BR> the back of the tank.<BR>
<p>
<U>Twice / Year<BR> </U>40+<B> Oil vaporizer</B> motor through the clear
tubes attached to the exhaust vent with a <BR> synthetic 5W/30 motor
oil.<BR> 40+<B> Check fire extinguisher</B> pressure gauge.<BR>
<p>
<U>Yearly<BR> </U>40+<B> Remove finished compost</B> from the front
portion of the tank only. DO NOT empty <BR> the tank! The manufacturer
recommends removing finished compost )
inches below
the top of the divider bulkhead to approximately 12 inches behind the
divider bulkhead. This will amount to about 2 cubic feet of material."
Compost may
not need to be removed every year or for the first
several years of operation. Early
summer is the best period to
dispose of finished compost because of the occurrence
of high soil
organism activity. The finished compost should be spread thinly on the
forest floor and away from the camp and water sources. Care should
be taken when
handling and spreading the finished compost because of
the potential that
pathogens remain. Non-organic material should be
bagged and disposed of off
USFS land.
40+ Check wood chip
supply stored inside Crag Camp and contact Camps
Supervisors to
re-stock. The manufacturer recommends using thumbnail-size
hardwood
chips (no cedar or redwood chips).
40+ The manufacturer recommends
that the fusible link on the fire extinguisher be
changed yearly. The link is date stamped on the brass disk.
Replacement links are
available from Bio-Sun. The fusible link
screws into the fire extinguisher pressure
gauge.
40+ Clear
out ditch extending from the northwest corner of the tank to insure
adequate
drainage.
B) Other Responsibilities
Above
40_ F Temperatures
-
* IMPORTANT * The waste pile at the
back of the tank should be mixed
thoroughly once a
month between June 1 and September 30. Using the long
handled garden
hoe, rake and shovel, the pile should be turned and aerated,
intermixing wood chips with fresh waste. Additional wood chips should not
be added
to the pile. The wood chips and the waste should be
uniformly mixed. New waste
should be pushed to the back of the tank
(away from access door). Access the
waste pile from the left side of
the exhaust vent when facing the access door. Knock
off excess waste
particles on the hoe into the tank and store hoe outside. Remove
any
mulch material that may have fallen in front of the bulkhead divider in
the float
switch area. Be careful not to contaminate yourself during
the mixing. Wash
thoroughly with anti-bacterial soap afterwards.
- Dust off photovoltaic panel periodically with a cotton rag.
-
The black box around the tank will have to be re-stained
(not painted) every
several years Use an oil-based black stain such
as Thompson's brand wood
protector. DO NOT stain or paint over the
cedar shingles.
- The door and window frame will need to be
re-stained with a clear wood
preservative periodically.
- Trim the tops of trees on the SE, S and SW sides of the
photovoltaic panel
periodically. A small shadow on the panel will
decrease the voltage output
significantly.
Below 40_ F
Temperatures
- Clear snow off of photovoltaic panel with a
broom and from the ramp with a snow
shovel after every precipitation
event. The panel should be carefully brushed but
not scraped.
-
The liquid level will have to be checked in the spring and the waste cone
that forms
beneath the toilet seat may have to be knocked over
several times during the cold
season. Therefore, the access door
area should remain free of snow in order to
access the waste pile
and check the liquid level.
C) Tools / Supplies Needed
Tools
- Garden hoe
- Rake
- Long-handled shovel
- Short-handled shovel
- Snow shovel
- Broom
Supplies
- Wood chips (hardwood, thumbnail size, no cedar or redwood)
-
Extra 5 amp fuses (cylinder-shaped automobile type)
- Extra relay
- Anti-bacterial soap
- 2 locks with keys for access door and control
panel door
- Toilet brush
- 5 gallon bucket
- 30 gallon
plastic garbage can
- Synthetic 5W/30 motor oil (for vaporizer
motor)
- Cotton rags
- Bleach
- A faucet attached to a hose has been
installed at the access door area of the tank. If
an overflow
situation is expected, the caretaker can drain liquids into a provided
bucket. The caretaker should mix bleach (store-bought brand) with
the liquid. The
ratio should be 1 ounce bleach to 1 gallon liquid.
The bucket should be mixed with a
stick and then stored overnight.
Some foaming will occur and should be expected.
Empty the bucket
into a nearby hole. The hole should be approximately 2 feet deep
and
away from the camp and water supplies.
- If the high liquid light
does not illuminate when test button is pressed check 1) that
there
is adequate sunlight, 2) the fuse in the control panel, 3) the light bulb,
4) the
wiring.
- If vaporizer does not run when the float switch
is activated check 1) that there is
adequate sunlight to power the
vaporizer, 2) the temperature is above 36_ F, 3) the
relay adjacent
to the float switch (FS-1) is not faulty, 4) the vaporizer is not
damaged.
Flies
- Flies can be controlled by installing a
non-toxic fly strip near the access door inside
the waste tank and by
adding wood chips more frequently. DO NOT add more than
is
recommended.
Volume
- If the problem of excessive waste
volume within the tank occurs, remove waste from
the front of the
tank into a 30 gallon plastic garbage can. A bleach (store-bought
brand) and water solution of 1 ounce bleach to 1 gallon water should be
added to
the garbage can. The waste should be saturated with the
solution. The contents of
the garbage can should be mixed thoroughly
with a stick and left overnight. The
contents should then be emptied
into a nearby hole which is 2 feet deep and away
from the camp and
water supplies. A vermiculture or enzyme additive can be
introduced
to the compost pile to aid the composting process. Contact Camp
Supervisors or Bio-Sun, Inc. for further information.
Fan
-
If the fan needs to be serviced, remove the ventilator from the top of the
chimney.
The back wall of the chimney may not have to be removed.
The fan is attached to
the stainless steel fan housing with two hex
head bolts. The fan should be installed
so that the blades face up.
This will draw the air upwards. If the fan is blowing air
into the
tank simply reverse the wires in the control panel. Check the air flow
direction by lighting a match near the toilet seat and observing the
smoke. Re-
silicon the ventilator casing to the top of the chimney
walls when finished.
Odors
- Odors can be controlled by
adding wood chips or by making sure the fan speed
control is on full.
DO NOT add more than is recommended.
For technical assistance or questions contact: