HomeMy WebLinkAbout08.a. (Handout) TuckerAddressing the Septic Tank Controversy
Jill Tucker
Orinda CA 94563
July 19, 2012
$.a.
( Handout)
Tucker
(2-pp)
Members of the Sanitary District Board have stated or implied that septic tanks are bad
for the environment, whereas sewers are good. Recent presentations have included some
contrary facts and of course, we've all seen and read about aging sewer pipes rupturing
and spewing thousands of gallons of waste onto city streets. In comparison, those of us
who urge you not to make an exception to the CAD policy have presented evidence that
properly maintained septic systems can function well for decades.
It has even been mentioned by the District's engineer, Mr. Mills, that septic tanks
perform, on a local level, the same service as the Sanitation District. There are five or six
pumping stations in Orinda, moving sewage continuously to Martinez. In fact, it could
be argued that our septic tanks save the District money in that we are not part of that
system.
The people who inhabit Upper El Toyonal hill are overwhelmingly college- educated
professionals and small business owners — some now retired - who care deeply about our
environment. We maintain our septic tanks, checking for leaks and when necessary
pumping them out. I believe that not one of us would knowingly, thoughtlessly or
recklessly pollute the drinking water supply for hundreds of thousands of people
(including ourselves).
Yet, many of those who support the advance of the sewer claim that the area smells rank
after it rains and have concluded that the odor is emanating from leaking septic tanks.
But there are about two dozen horses and an equal number of cattle in the immediate
area. As you will see from Attachment B, the average horse drops nine tons of urine and
feces on the ground every year. Both horses and cattle release the same ammonium
nitrates as found in human waste, and with a similar smell. Right now, horses and cattle
outnumber the humans who inhabit this part of the hill. Their droppings are deposited in
neither septic nor sewer systems.
We believe that if lot owners want to hook up to the sewer, they should do so at their own
expense, and those who wish not to participate should not be penalized. Those of us who
live in our homes have many other concerns and expenses related to the area's geological
fragility, the extreme fire danger in summer, the rain forest -sized downpours in winter
and our location so near the Hayward Fault.
I ask that you reconsider the exceptions to the CAD policy that would force a debt upon
septic tank users who are responsible, environmentally conscious citizens. I further ask
you to reconsider the assumption that all septic systems are bad and all sewers are good.
When we apply the word ALL, we can almost always be proved wrong.
ATTACHMENT B Website:
http: / /www.esc.rutgers.edu /pubi !cations /stablemgVFS036.htm
Horses and Manure
Michael Westendorf, Extension Specialist in Animal Sciences & Uta Krogmann, Extension Specialist in Solid Waste Management
Published 21162004
Fact Sheet # 036
Manure Quantity and Composition
A 1000 -pound horse will defecate from 4 to 13 times each day and produce 35 to 50 pounds of wet
manure (feces plus urine) daily, or approximately 9.1 tons per year. Typically a ton of horse manure will
contain 11 pounds of N, 2 pounds of P, and 8 pounds of potassium (K). To obtain more accurate
numbers, manure should be tested for nutrient content. Check Rutgers Cooperative Extension fact sheet,
FS935, Feed and Forage Testing Labs for more information.
Nutrients: When not managed properly, horse manure (feces and urine) can pollute the environment,
mainly as ground or surface water pollution due to the nutrients nitrogen, phosphorus, and
carbon (organic matter). These nutrients can reach waterways as surface runoff or leachate from
the manure pile.
Nitrogen excreted from horses is usually present either as urea in urine, which is quickly converted to
ammonia (NHA or it remains in association with organic matter in the feces. Ammonia (NH3) can be
volatilized into the atmosphere. If NH3 from horse manure comes into contact with surface waters, it
can cause nutrient enrichment and excessive algae growth. This process is referred to as
eutrophication. Eutrophication is the process of nutrient enrichment in a lake or slow- moving stream
occurring when excess nutrients from manure, fertilization, sewage, etc. are deposited. This can result in
waters rich in mineral and organic nutrients that promote a proliferation of plant life, especially algae,
which reduces the dissolved oxygen content and often causes the extinction of other organisms.
(Adapted from Concise Columbia Electronic Encyclopedia, 1999 & American Heritage Dic. of the English
Language, 4th ed.) In the case of nitrogen, the excessive algae and conversion of ammonia to nitrate
(NO3) causes a reduction in dissolved oxygen in the water, which can contribute to fish kills through
oxygen depletion.
Nitrogen present in organic matter in horse urine and feces will be converted in the soil to ammonia
and then nitrate, which can be taken up by plants. If plants do not take up nitrate it will easily move
through the soil and can eventually leach into the groundwater where it can be a human health concern.
Nitrate can also undergo the process of denitrification in the soil and be lost into the atmosphere as
gaseous nitrogen (NO, NZO, or Nz).
Phosphorus is also present in manure. When spread on the land it will not leach like nitrogen, unless
the soil matrix where phosphorus binds becomes overly saturated with phosphorus. However,
phosphorus will run off if applied at the wrong time of the year and /or when soil erosion occurs. This can
lead to contamination of surface waters where it may cause eutrophication.
When manure is not properly incorporated into the soil, organic matter present in manure (contains
carbon, nitrogen and phosphorus) can be a concern when it runs off into surface waters. Eutrophication
and additional oxygen depletion may occur due to the decomposition of the organic matter.
Pathogens and Vermin: In addition to the above concerns, pathogens may be present in manure.
Some of these are, E. Coll, Salmonella, and Cryptosporidium parvum.
0