Investigation of the feasibility of testing one or more alternative on-site sewage treatment systems in the Richmond region

[From the U.S. Government Printing Office, www.gpo.gov]

FY 1992 FINAL PRODUCT Task 34
Technical Assistance

An Investigation of the Feasibility
of Testing One or More
Alternative On-Site Sewage Treatment
Systems in the Richmond -Region

Prepared by the
Richmond Regional Planning District Commission

November, 1993

A Report of the Virginia Department of Environmental Quality's
Coastal Resources Management Program pursuant to
National oceanic and Atmospheric Administration Award
No. NA27240Z0312-01

This paper is funded in part by a grant from the
National oceanic and Atmospheric Administration.
The views expressed herein are those of the author and do not
necessarily reflect the view of NOAA or any sub-agencies.

An Investigation of the Feasibility
of Testing One or More
Alternative On-Site Sewage Treatment Systems
in the Richmond Region

According to a report issued by the Task Force on Septic
Regulations, 650,000 year round housing units in Virginia use on-
site sewage disposal systems. That represents slightly over one
third of all housing in Virginia. In rural areas, more than 70*1 of
all households and most businesses depend on on-site systems.'

1@y far, the vast majority of households served by on-site
systems are served by conventional septic tank/drainfield systems.
These systems represent a safe, cost effective way of treating and
disposing of household and small business sewage. Properly sited,
designed,2installed and maintained, such systems can last for up to
50 years.

Unfortunately the conditions necessary for such long term
service are not always available. Some home owners have difficulty
finding a site suitable for a septic system on their property. In
addition, septic systems sometimes fail, that is, stop operating
properly. In fact, it is reported that one half of all septic
systems in the United States fail after only 15 to 20 years. 3

The problems associated with the installation of new septic
systems and the failure of exiting systems are found here in the
Richmond region. Installation can be difficult due to poorly
drained soils and high water tables, especially in the coastal
plain. These same factors can also lead to septic system failure.
As development continues to occur in the coastal plain, finding
sites that meet the requirements of the property owner and the
Virginia State Board of Health, the agency that regulates septic
systems, may become more difficult.

The purpose of this report is to examine the issue of
household wastewater and how traditional septic systems work. The
report also examines factors that limit the location of septic
tanks and what causes these systems to fail.

'Re-oort of the Task Force on Septic Regulations, Institute for
Environmental Negotiations, University of Virginia,
(Charlottesville, Virginia, July 1991), p. 4.

2Kathryn 0. Sevebeck and Carolyn J. Kroehler, A Guide to Septic
.Systems and Alternatives, Virginia Water Resources Research
Center, Virginia Polytechnic Institute and State University,
(Blacksburg, Virginia, 1992), p. 1.

31bid.

The report then examines alternatives to traditional systems.
Three alternative systems are discussed along with the strengths
and weaknesses of each system.

The report then discusses the need for more information
concerning alternative sewage treatment systems. It examines how
such information could be gathered. Finally, the likelihood of
conducting such an examination in this region is examined.

During the course of this investigation, RRPDC staff members
talked with many individuals familiar with traditional septic
systems and alternative sewage treatment systems. Individuals for
the Virginia Department of Health and Virginia Polytechnic
Institute and State University were interviewed. Also interviewed
were individuals involved in the distribution of equipment used to
construct alternative systems and persons involved in the
installation of on-site waste water systems. A complete list of
those that helped with the preparation of this report is included
in the acknowledgement section.

WASTEWATER CONTAMINANTS

Wastewater treatment is necessary because of the many
contaminants found in the water. While sewage entering the
traditional septic tank is 9901 water, it contains biological,
physical and chemical contaminants. Following is a brief
description of these contaminants taken from The Systematic
Evaluation and Re-pair of Failing Drainfields in the Coastal Zone
Area of Virginia, published by the Department of Health .4

Biological Contaminants

Domestic sewage contains bacteria and viruses. Some of these
organisms can cause disease. The presence of these contaminants is
measured indirectly by testing for fecal organisms such as fecal
coliform and fecal streptococcus bacteria. These are used as
indicators to determine the presence of sewage in water.

The septic tank itself provides little wastewater treatment.
It is the conditions found in the drainfield that reduce the
bacteria in the wastewater. Simply put, the purpose of the septic
tank drainfield is to reduce or eliminate these bacteria as the
water seeps through the soil beneath the drainfield. This happens
as the bacteria competes with native soil bacteria and organisms in
the drainfield trench, as the wastewater is filtered by the soil

4Donald J. Alexander, M.S., Calvin Jones, and Paul Sandman,
M.S., The Systematic Evaluation and Repair of Failing-Drainfields
in the Coastal Zone Area of Virginia, Virginia Department of
Health, Division of Onsite Sewage and Water Services, (September
25, 1992).

and as the bacteria die off due to time and hostile environmental
conditions.

Viruses in the wastewater are treated in a different manner.
They are adsorbed by the soil due to the difference in electrical
charges between the negative charge of the soil and the positive
charge of viruses. As it turns out, clayey soils have a higher
ability to adsorb viruses than sandy soils.

Physical and Chemical Contaminants

One element used to evaluate wastewater is biochemical oxygen
demand (BOD). A f ive day biochemical oxygen demand test (BOD.)
measures how much oxygen must be consumed to biologically digest
and chemically stabilize the organic components of wastewater.
While BOD is not a contaminant, it does provide a way to determine
the characteristics of wastewater.

Another contaminant is suspended solids. These are materials
such as filamentous material, hair and biological wastes. These do
not always settle in the septic tank. High suspended solids can
clog pumps and other machinery in a treatment system as well as the
soil pores in the absorption field.

A final contaminant is nitrogen, considered by some to be the
most important chemical constituent in wastewater. Nitrates,
forms of nitrogren which come from urin, are highly soluble in
water and do not bind to soil. Nitrates can cause both public
5
health and environmental problems.

HOW A SEPTIC TANK/DRAINFIELD SYSTEM WORKS

The traditional septic system is rather simple in design. It
works totally on gravity and has no moving parts. A septic system
consists of the septic tank which collects the wastewater and
solids, a distribution box which splits the wastewater (effluent)
evenly among a series of drain pipes and an absorption field 6 which
allows the wastewater to percolate (seep) into the ground.

Treatment of household sewage begins when it enters the septic
tank. Here heavy solids sink to the bottom. These solids are
acted on by bacteria through a process of known as anaerobic
(without oxygen) decomposition. This process creates a material
called sludge which sinks to the bottom of the tank and must
periodically be pumped out of the tank. The liquid from the tank
floats to the top. Grease and light particles remain in the tank

'Alexander, Jones and Sandman, pp 3-6.

6Sevebeck and Kroehler, p. 3.

due to an outlet tee. Wastewater is transported to the
distribution box and to a series of perforated pipe or open jointed
drain tile buried in the ground. There the wastewater passes
through a layer of coarse gravel and then enters the soil in the
absorption field. Bacteria and oxygen in the soil help treat the
liquid. Eventually the treated water reaches the groundwater.'

While the process of wastewater treatment in a septic system
is biologically complicated, the system itself is relatively simple
from an engineering point of view. In addition, it is relatively
inexpensive to build and maintain. In 1991, it was estimated that
the average cost of installing a septic tank was between $3,000 and
$4,000, depending on location, size, engineering and other
variables. Maintenance is usually limited to the periodic pumpout
of the tank.8

A variety of factors are examined to determine if a particular
site is appropriate for a septic tank system. These f actors
include topography, available area, soil type and depth, slope of
the land, depth to water table, proximity to drinking water
supplies, bodies of water and shellfish areas, and the ability of
the soil to absorb moisture (percolation rate).9

The installation of a septic system, and all other types of
on-site, non-discharging systems is governed by regulations issued
by the Virginia State Board of Health. These regulations detail
the requirements for the siting and installation of septic
systems.10

7Small Wastewater Systems: Alternative Systems for Small
Communities and Rural Areas, U.S. Environmental Protection Agency,
Office of Water Program Operations, (Washington, DC, January 1980),
no page number.

8Peterson, Craig E. and Thomas W. Simpson, Alternative On-site
Wastewater Treatment and Disposal Systems, Department of Crop and
Soil Environmental Sciences and Virginia Cooperative Extension
Service, College of Agriculture and Life Sciences, Virginia
Polytechnic Institute and State University, (Blacksburg, Virginia,
1992), p. 9.

'Peterson and Simpson, p. 10.

"Regulations governing discharging wastewater treatment
systems are governed by the Water Division of the Department of
Environmental Quality. Those systems and regulations are not
discussed in this paper.

LIMITATIONS TO THE USE OF TRADITIONAL SEPTIC TANK SYSTEMS

The low cost and ease of installation of a traditional septic
system, plus the minimal maintenance requirements make this type of
system very attractive. And for a great majority of homeowners and
businesses, this type of system is the best and most economical way
to deal with wastewater.

There are some areas, however, where the installation of a
traditional sept.ic system may present problems. This was
discovered in work done by the Richmond Regional Planning District
Commission. The Commission assisted both New Kent County and
Charles City County with the preparation of their land use plans.
In each case, the RRPDC worked with representatives of the U.S.
Soil Conservation Service, the Virginia Department of Health,
Virginia Polytechnic Institute and State University and each county
to determine the suitability of soil types for on-site sewage
treatment. Conditions such as soil permeability, depth to water
table, slope and existing Department of Health regulations were
examined to determine the potential for installing conventional
septic systems. In both counties, it was determined that over 60%
of the generalized soil types in each county had severe limitations
for the installation of on-site wastewater treatment systems,
especially septic systems. The predominant reason for this
determination was the presence of wet soils that could not
adequately absorb wastewater from a septic system.

This does not mean that development is at a stand still in
these two counties. Houses are being built and septic systems are
being installed on a regular basis. It does mean, however, that
siting septic tanks is difficult at best. It also means that some
land that is desirable for development is not being developed.

SEPTIC TANK FAILURES

Septic system failure can be an inconvenience. They can also
be a potential threat to the homeowner and the general public.
Liquid waste can back up into the residence or business. Liquid
waste can also pond on the property creating a health hazard due to
viruses and bacteria and providing breeding places for mosquitoes
and other insects.

Equally important, a failed system can contaminate ground and
surface water. Improperly treated wastewater can allow bacteria,
viruses, detergents and a variety of potentially toxic chemicals
found in household cleaners to enter ground and surface water.
This type of problem may be more difficult to detect since
contamination can occur to groundwater without any outward signs."
According to the U.S. Environmental Protection Agency, septic

I'Sevebeck and Kroehler, p. 15.

systems are the most frequently reported sources of groundwater
contamination in the nation. 12

There are four primary reasons for the failure of a septic
system. These are hydraulic overloading, failure of a physical
component due to stress or deterioration, landscape problems and
unsuitable soil conditions. The following discussion is taken from
the aforementioned Systematic Evaluation and Re-pair of Failincr
Drainfields in the Coastal Plain Area of Virginia.

Hydraulic Overload

Hydraulic overload occurs when more effluent (wastewater) is
applied to the drainfield than can be absorbed by the drainfield.
This can occur periodically or, in some instances, can occur all
the time. According to some sources, excessive overload of the
drainfield may be the leading cause of drainfield failure.
overloads can be caused by several factors.

One possible cause is water usage in excess of the designed
capacity of the septic system. A growing problem is increased
water usage. This can come from such varied sources as the
addition of a hot tub, a home occupation such as a beauty shop or
a hobby such as photography. Any of these factors can add extra
flow which may exceed the capacity of the drainfield to absorb the
wastewater.

Another problem is leaking fixtures. A small leak can add the
equivalent of an additional bedroom to the daily wastewater flow.
A severe leak or leaks can double the estimated wastewater flow.

Another problem stems from the design of the traditional
septic tank system. As discussed above, the system contains a
distribution box to equalize the flow to the drainfield. Equal
distribution among the drain lines is difficult to achieve. The
uneven flow may not cause a problem in flat terrains. However, in
sloping terrains, problems can develop, especially if downhill
lines receive added flow. This problem can be increased if the
distribution box was not properly installed.

Physical Failures

One problem associated with a conventional drainfield is tree
roots. Water loving trees such as maples can send roots out to
drainfields, even when located 100 feet or more away. These roots
can enter the drainfield, grow back to the distribution box and
septic tank and block the flow of wastewater.

12 Sevebeck and Kroehler, p. 1.

Some failures are caused as materials used in the system wear
out. Some older materials such as piping and some concrete
products have a history of early failure. Some modern materials,
such as plastic pipe, tend to not deteriorate, but are subject to
stress. Some failures of materials are caused by operating heavy
machinery over the drainfield.

Another cause of failure associated with older systems or ones
that are not well maintained is clogging or organic mats. A mat
forms at the interface between drainfield lines and the soil. This
is normal. However, there are activities that cause this mat to
clog the system. The use of garbage disposals increases the
organic loading placed on the system. Compounds such as cellulose,
which are difficult to breakdown in the septic tank, can also cause
problems. A third problem is related to the excessive water flow
caused by hot tubs which increase the loading on the system.

Soil Related Failures

one soil related problem can be a high seasonal water table.
These high water tables usually occur due to site or soil
conditions that do not allow the adequate disposal of precipitation
falling or flowing onto the site. Wastewater disposal adds to the
problem. Treatment efficiency is reduced due to an increased need
for time and distance to adequately treat wastewater.

Another problem is slow infiltration rates for soils. That
is, the soil is very slow to allow water to pass through it. In
these types of soils, treatment and disposal is directly related to
rainfall. When rainfall is high, normally spring and fall,
treatment will be lessened. The ability of soils to transport
rainwater and wastewater is important due to the heavy load a
septic systems places on the soil. While rainfall in Virginia is
ypically 40 inches per year, adding a drainfield adds the
equivalent of 120 additional inches of rain per year.
t

High shrink-swell soils, soils which contain active clays,
generally have difficulty providing treatment for wastewater. These
soils expand when they are wet and shrink when they are dry. The
addition of wastewater to these types of soils causes the soil to
swell shut, leading to system failure.

A final problem area is soils that have what is called
restrictive horizons, or barriers in the soil which slows the
downward flow of water. These soils may also contribute to what is
called "perched" water tables which, due to soil conditions, limit
the downward flow of water. The closer this restrictive layer is
to the drainfield and the less the permeability (ability to pass
water) of the soil, the greater the problem."

"Alexander, Jones and Sandman, pp. 7-12.

ALTERNATIVE ON-SITE SEWAGE TREATMENT SYSTEMS

Alternative wastewater treatment systems were developed to
address the limitations of conventional septic systems. That is,
these alternative systems were designed to work where traditional
septic systems cannot work. Furthermore, they are designed to
address conditions which may lead to the failure of a traditional
septic system.

There are a variety of these types of alternative systems.
Many of them inc*(orporate the traditional septic tank, but use a
variety of means to dispose of the wastewater. Each system was
designed to overcome one or more conditions that limit the
installation of a traditional system. Each system has its pros and
cons as well as its proponents and detractors.

After conversations with many people ' RRPDC staff selected
three systems which appear to address some or all of the
constraints that limit the installation of a traditional septic
tank system. These systems are low pressure distribution systems,
elevated sand mounds and constructed wetlands. Following is a
brief description of each of these systems.

Low Pressure Distribution Systems

A low pressure distribution system is designed to overcome
some of the constraints which limit the use of traditional septic
system. Specifically, low pressure distribution systems can work
in rapidly permeable coastal sands, inland soils with high water
tables and in situations where the area available for wastewater
disposal is small relative to the space needed for a conventional
absorption field. 14

These systems are designed to maintain an even distribution of
wastewater in the entire absorption field, optimize dosing and
resting cycles and provide for maximum separation of the
distribution lines above the water table and any restrictive soil
layers. These systems can effectively utilize the treatment
characteristics of the soil, reducing the travel distance of
pollutants."

A low pressure distribution system begins with a traditional
septic tank. To this is added a dosing tank and pump. The pump
evenly distributes wastewater through a series of perforated
plastic pipes that replace the traditional absorption field. This
allows for a more efficient distribution of the wastewater through
the entire drainfield. This system also allows the drainfield to

14 Peterson and Simpson, p. 61.

"Peterson and Simpson, p. GO.

dry between dosings. In some applications a second septic tank is
used to provide more settling room for solids. The drainfield may
be the same size as that of the conventional septic tank/absorption
field system, but regulations may permit a reduction of the
drainfield size by up to 50 percent. 16

These systems can cost twice as much as a traditional septic
tank system to install. Furthermore, there are periodic
maintenance costs and energy costs which need to be paid on a
17
regular basis.

Evidence indicates that low pressure distribution systems are
suitable for use in areas of rapidly permeable coastal sands, some
inland soils with high water tables and some soils with restrictive
horizons. However, it must be remembered that while these systems
are effective in environmentally sensitive areas, they do have
constraints that limit their application. one report indicated
that these systems do not always operate properly in areas with
high water tables. This was due to ground water infiltrating the
pump chamber. Simply stated, low pressure distribution systems are
not a cure all for site problems, but can perform better than
typical septic systems when properly designed.'8

FIGURE I

LOW-PRESSURE DISTRIBUTION SYSTEM

Septic Tank Perforated Plastic Pipe

Dosing Tank
with Pump

Source: A Guide-to Sentic Systems and Alternatives, Virginia
Water Resources Research Center.

"Sevebeck and Kroehler, p. 27.

17 Ibid.
@c4

"Peterson and Simpson, pp. 61-62.

Elevated Sand Mounds

Another alternative is the elevated sand mound system. The
elevated sand mound was developed to overcome several problems.
These include high seasonal water tables, slow permeability of
soils and shallow soil to bedrock.19

The sand mound system includes a traditional septic tank, but
a mound of sand is used to raise the level at which the wastewater
.s disposed into.-the ground. In addition, there is a pumping
chamber, an effluent pump, high-water alarm, supply line,
perforated distribution lines and a mound made of sand covered with
soil. The perforated pipe is placed in the sand mound. The
purpose of this mound is to increase the amount of soil available
to treat the wastewater. A two chamber septic tank or two tanks
placed in series are sometimes recommended to reduce solids that
may clog the distribution pipes.20

FIGURE 2

MOUND SYSTEM

Perforated Pipe

Absorption Field
Topsoil
Inlet Pipe from Vegetation
Septic Tank Sol-I Fill & Sand@'

Plowed Surface, Original Grade
Cross
Section
Diagram

Source: A Guide to Septic Systems and Alternatives, Vir ginia
Water Resources Research Center.

19peterson and Simpson, p. 101.

Sevebeck and Kroehler pp. 28-29.
Topsoil Absorptio,
m
ro
nLk @ _.,W
0\@S @O@ @i I I & S a n @d

The operating mechanism of a mound system requires periodic
maintenance. In addition, the mound itself must be keep free of
traffic and free of deep-rooted plants. Costwise, the mound system
can cost two to five times more than a conventional septic system.
21
Plus there are annual maintenance costs to pay.

Mound systems have had problems. one evaluation in
Pennsylvania found 5111 of the mounds malfunctioning. The causes
were related to poor site selection, system design and construction
techniques, including improper, but cheaper, sand. Improper site
evaluation often leads to insufficient separation between seasonal
high water tables and impervious soils. Failure to pump out the
septic tank also contributed to failures. A later study indicates
that systems that are adequatel@ sited, designed, constructed and
maintained have fewer problems.

Constructed Wetlands

Constructed wetlands are yet another alternative sewage
treatment system. Constructed wetlands have been used in clay
soils where percolation rates are very slow. In conjunction with
sand mounds, constructed wetlands have been used in very wet soils.
They have also been used where nitrogen contamination of ground and
surface water was a concern due to their ability to denitrify
wastewater. 23

A constructed wetlands system begins with a typical septic
tank. The septic tank removes coarse and heavy solids. To this is
added one or more wetland "cells". Two cells are normally used in
residential applications. These cells are basically constructed
areas that contain wetlands plants growing in a medium.

Wastewater enters the f irst cell where it is distributed
evenly across the width of the cell by a series of pipes and
valves. This cell contains a plastic sheet liner on the sides and
bottom which keeps the water from escaping. Wetland plants placed
in gravel f ill the cell. As the wastewater passes through the
cell, suspended solids are filtered. Trace metals are absorbed by
plants and organic material. organisms in the wetlands, along with
the roots of the plants, use these organic materials and nutrients
as food. The plants provide the oxygen needed by the organism.
Plant roots keep the rocks and soil loose so that water flows
through them easily.

21 Ibid.

22 Peterson and Simpson, pp. 101 and 102.

23 Peterson and Simpson, p. 190.

FIGURE 3

CONSTRUCTED WETLAND

Arrows indicate wastewater flow direction
2. Aquatic vegetation p!anted in gravel
3. Swivel standpipes regulate water level
4. Plant roots form a dense mat

L tA
re
Y

Source: A Guide to Sentic Systems and Alternatives, Virginia
Water Resources Research Center. (Revised)

The wastewater then passes into the second cell. which also
contains wetlands plants in a layer of sand. Sand is used in the
second cell to retain moisture and to aid the plants during dry
periods. Again the water is distributed through a series of pipes.
This cell is unlined, allowing the water to flow into the ground
below. (Note: Constructed wetlands can be built as described or
with a point source discharge or as a combination point source and
non-point source discharge system. Where the wetland is designed
to be a point source system, the second cell is lined.) They can

J')

be inexpensive to build and when compared to other alternative
systems, are relatively maintenance free. 24

There are limitations to the use of constructed wetlands.
They should be constructed away from major streams and springs to
avoid potential flooding and to avoid high water tables and
saturated soils. The sites should also be flat or gently
sloping. 25

NEED FOR ADDITIONAL TESTING OF ALTERNATIVE SYSTEMS

The above discussion examined three types of alternative
sewage treatment systems. while each has bee 'n used in Virginia and
in other states, discussions with a variety of individuals
indicates a general agreement that additional information is needed
about these systems. Specifically, more information is needed
about how these systems function in the various so il and water
table conditions found in the coastal region of Virginia.

In order to find out additional information about the
operation of these systems in the coastal plain, it has been
suggested that one or more of these systems be tested in this
region. These tests would involve actually installing one or more
of these systems in the ground and operating the system for a
prescribed length of time while testing the quality of the water in
or around the drainfield. The purpose of the remainder of this
paper is to discuss how such a test would be run and to examine the
feasibility of funding such a test.

TESTING THE SYSTEMS

Testing an alternative sewage treatment system would involve
several steps. These include the selection of the problem or
limitation that needs to be overcome, the selection of a system to
address this limitation, the selection of a site or sites to
conduct this test and the design of the procedure to test the
effectiveness of the system in dealing with the problem. Prior to
doing any work, however, it would be imperative to meet with
representatives of the Department of Health. Their assistance
would be necessary to obtain the necessary permits. More

24 General Design, Construction, and Operation Guidelines:
Constructed Wetlands Wastewater Treatment Systems for Small Users
Includincr Residences, TVA/WR/WQ-91/2, March 1991, Water Resources
River Basin Operations Resource Development, Tennessee Valley
Authority, (Chattanooga, Tennessee), pp. 1-17.

Constructed Wetlands, Tennessee Valley Authority, Chattanooga,
Tennessee. No date, no page number.

'Peterson and Simpson, p. 191.

importantly, their guidance and assistance during the process would
ensure that the results of the test would be useful to the
Commonwealth.

During the preparation of this report, the Department of
Health showed much interest in the testing of one or more
alternative systems. This interest is found both in the central
office and from local environmental health managers. Unfortunately
a lack of funding and staff has kept the Department from carrying
out this research on its own.

Condition to be Examined

The first step in the test would be to determine what
limitation or condition the test would attempt to address.
Discussions with Health Department officials indicate that there
are two problems that are normally encountered in attempting to
install an on-site sewage treatment system in the coastal plain
region. By far the most often encountered problem is a high
seasonal water table. Another problem is clay soils. These soils
can experience problems due to shrinking and swelling during dry
and wet periods. In addition, clay soils can have low perculation
rates. It would seem appropriate that sites with these limitations
be found and that systems to overcome these limitations be tested.

Site Selection

Once the specific limitations to be examined are selected, a
site would have to be chosen. Two options are available. A test
could be conducted at an actual residence or at a site selected
strictly for testing purposes. It appears that an experimental
site is preferable over an actual residence. First, this gives the
testing agency more latitude to control input. Second, there is
the possibility that the alternative system may not function
properly. This would mean additional expense to provide a properly
functioning system for the homeowner, not to mention the
inconvenience to the homeowner.

It has been suggested that a campus at one of the area, s
community colleges may be an appropriate site. Such a location
would have a source of wastewater input as well as provide an
opportunity for around the clock surveillance and access. The
issue would be f inding a site at one of these colleges that has the
desired limiting factors.

Another alternative would be a site owned by a local
government. This could be done in conjunction with a governmental
facility or on a vacant piece of property. A vacant site would be
preferable for the reasons stated above.

Yet another possibility is a parcel owned by a land developer
that has not yet been developed. This would demonstrate the
potential for the use of a system in close proximity to actual or
potential home sites. This would also allow the developer to
become involved in the test and may increase interest in one or
more alternative systems in the development community. This is
important if these alternative systems are ever to be used in more
than limited applications.

System Selection.

Once a site is selected, the specific type of system must be
determined to meet the needs of the site and of the issues to be
tested. As stated previously, each system has its strengths and
weaknesses when dealing with the various factors that warrant the
use of alternative systems.

System selection will be influenced by the funds available to
test the alternative systems. The costs of these systems vary.

Finally, the type of system selected may be impacted by the
amount of interest shown in the system. This report has discussed
three types of systems, but there are several other types of
alternatives available. As stated before, each has its supporters
and detractors. It may be a particular system is selected first
for'funding or other reasons. In that case, a site would need to
be selected that provides the appropriate type of conditions for
the selected system to attempt to overcome.

Test Design

The next step would be the actual design of the test. This
includes decisions about the length of the test, the number and
depth of the monitoring wells, how to provide influent to the
system and the number and timing of the test samples that will be
collected. Following are some broad guidelines that can be used to
begin to think about this phase of the process.

Ideally, there would be three phases to the test. The first
step would be to examine ground water quality at the site before
installation of a system. While this is not always done, due to
funding limitations, obtaining information about pre-test
conditions is strongly recommended. The second phase would be the
actual installation of the system. The final step is the actual
operation and testing of the output of the system under simulated
residential usage.

In developing a testing procedure, it is important to remember
that the State does not have specific standards for wastewater
effluent with regard to its impact on ground water. Therefore, any
testing should attempt to test the relative effectiveness of a
system to treat wastewater. In other words, the test should

compare the quality of water coming into the system (the influent)
with the quality of water leaving the absorption field (the
effluent). From this, conclusions can be drawn about the ability
of a system to treat wastewater.

Testing is usually done by taking water samples from a series
of monitoring wells. While the exact number of wells varies based
on the type of test being run, the topography of the- site and
funding, it is recommended that at least two to four wells be dug.
Many times these are very shallow wells, with a depth of
approximately six feet. on occasion, wells eight to ten feet are
professionally dug.

The influent and effluent of the system is sampled for a
variety of contaminants. These are fecal coliform, ammonia,
nitrates, nitrites, BOD (bio-chemical oxygen demand) , suspended
solids, orthophosphate, pH and TKN (total kjeldahl nitrogen) .
Again, it is important to determine exactly what you are trying to
evaluate in order to determine what tests need to be run.

Decisions also need to be made about the length of the testing
period and the frequency of testing. While recommendations vary,
it is important to take sufficient samples to properly test the
performance of the system. Ideally tests of pre-installation
conditions should be run for a period of 3 to. 6 months to establish
base data. Water samples should be taken at least every 2 weeks at
the beginning of the testing period. It may be possible to reduce
testing time to once per month if there is no variability in
results.

During the actual testing of effluent, it is necessary to test
water samples every one or two weeks. Again, if there is no
variability in samples, it may be possible to reduce testing to
once per month. If there is a considerable amount of variability
during first the 18 months, additional sampling may be necessary.

The actual period of testing should be a minimum of 18 months.
Preferably, the test should be run for a longer period, with 36
months being a preferred length.

The important point to remember before developing any testing
scheme is to be sure what the test is attempting to accomplish.
Clear goals are needed regarding the purpose of the test. The main
reason for testing any sewage treatment system is to determine the
performance of the system. The principal issues that need to be
examined are how effective is the system in treating the wastewater
and/or how effective is the system in disposing of the wastewater.

PROJECT COSTS

The total cost of the project will be based upon three
factors--the goals of the monitoring program, the type of system

being tested and the number and frequency of water samples that are
taken for testing. As stated previously, alternative treatment
.systems can cost between $7,500 and $15,000. Testing can cost
$1,000 per month and more. Therefore, a test of alternative
systems could cost $50,000. This is a substantial amount of money.
However, the results of this test would add greatly to the body of
knowledge available about alternative systems.

FUNDING THE PROJECT

Funds for testing alternative sewage treatment systems in
Virginia are almost non-existent. While the Department of Health
wants and needs additional information about such systems, their
resources are stretched to the limit. Anyone contemplating any
funding from that Department will find much enthusiasm, but little
or no money.

Virginia Polytechnic Institute and State University does
conduct tests similar to what is being proposed. It may be
possible to work with Virginia Tech to arrange full or partial
funding for such a test.

Funding from a non-profit organization such as an
environmentally and/or water quality focused organization may be
possible. During the course of the investigation, one such agency
was approached about funding such an activity. Unfortunately funds
were not available. However, there are agencies that have a high
level of interest in protecting water quality that may be of
assistance. The Virginia Environmental Endowment may be one such
agency.

Another possible source o f funding is the private sector.
While there may be funds available, preliminary inquiries again
turned up much enthusiasm for such a project, but limited funding
possibilities.

one area investigated was manufacturers of the equipment used
to construct alternative systems. It was discovered that these
systems are essentially a collection of pumps, piping and other
materials that are put together by the installer. There is no real
alternative system "industry". The large, well funded corporations
that fund experiments for other types of wastewater testing do not
exist. Since most of these parts are made by small manufacturers
and/or by companies that sell the parts for a variety of
applications, there appears to be little interest or capital
available from this sector.

Another possibility is the home building industry. Developers
are looking at ways to construct homes in a variety of locations.
Some of these are without public sewer and are marginal when it
comes to the installation of traditional septic tanks. Funding
from this source may be possible.

PROJECT PARTICIPATION

While finding financial support for testing these alternative
systems is very important, and will be difficult, there is another
type of support that must be garnered. That is the support of the
various agencies and groups that will contribute to public
acceptance of alternative sewage treatment systems. The needs and
concerns of these groups have to be addressed before and during the
testing period.

The Department of Health must be involved from the beginning.
The Department continues to show great interest in testing
alternative systems and, as the preparation of this report has
shown, the Department is willing to help with efforts to expand the
information available concerning these alternative systems. Their
involvement in any testing is vital.

Another group that will need to be included in the testing
process is the development community. This includes developers,
builders and realtors. These individuals must be given a chance to
see how these alternative systems are installed and how they
function. It is important that this segment of the community
understand and have confidence in alternative systems. If they
do, they will be more likely to support the use of these systems
and recommend these systems to potential home owners.

Local officials must also be involved in this process. As
with the development community, local elected and appointed
officials must become comfortable with these alternative systems.
If they are not, local governments are less likely to approve new
developments that depend on these alternatives systems for sewage
disposal.

Finally, the individuals in the community that will be
installing these systems in the years to come must see and
understand these alternative systems. These individuals must
understand these systems and support them. If they do not, the
likelihood of local acceptance is reduced.

Therefore, any testing program must be widely publicized.
Efforts.must be made to involve the parties mentioned above. They
should be involved from the beginning. Furthermore, the
installation process must include time for these groups to see how
these system are actually constructed, from ground breaking to
final completion. These groups should also be involved in the
testing phase. They need to understand why the testing is being
conducted, what the results are and what these results mean.

It may be appropriate to form a technical advisory committee
with representatives from these various interest groups as part of
the test procedure. This advisory committee could be involved-in
decision making regarding the test. It could also help publicize

the results of the test. The more local people are involved and
understand the strengths and limitations of these alternative
systems, the more they are likely to support to use of these
systems in they future.

CONCLUSION

This paper has examined the issue of alternative on-site
sewage treatment systems. It has also examined the feasibility of
testing one or more systems to find determine their suitability in
the coastal plain region. Several conclusions can be drawn based
on the information presented.

1. Septic tank/drainfield systems are, and will continue to
be, the system of choice for most people. This is due to
the low installation costs, low maintenance costs and
relative ease of operation.

2. Septic tanks are highly effective, but will not work in
every situation.

3. Alternative sewage treatment systems expand the options
available to land owners by permitting development on
sites where traditional septic systems cannot be located
or have failed.

4. of the variety of alternative systems exist, the types of
systems most commonly mentioned during the preparation of
this paper were low pressure distribution systems,
elevated sand mound and created wetlands.

5. While alternative systems have been tested before, there
is substantial interest in testing these systems further
to determine their effectiveness under varying conditions
in Virginia, especially in the coastal plain region.

6. Any testing of such systems should involve both the
Department of Health, local officials, land developers
and installers.

7. Public money for additional testing is in very short
supply and may not be availalbe. Private funds may be
available, but this is not certain.

8. Any effort to fund additional testing will require a
concerted effort to involve public regulators, local
governments, private installers, land developers and
realtors in the testing process.

Hopefully this paper will stimulate interest in this activity.
it is especially hoped that funding from one or more agencies or
individuals can be arranged to carry on this vital research.

BIBLIOGRAPHY

Alexander, Donald J., M.S., Calvin Jones, Paul Sandman, M.S. The
Systematic Evaluation and Repair of Failing Drainf ields in the
Coastal Zone Area of Virginia. Virginia Department of Health,
Division of Onsite Sewage and Water Services, September 25,
1992.

Constructed Wetlands, Tennessee Valley Authority, Chattanooga,
Tennessee. n.d.

General Design Construction, and Operation Guidelines:
Constructed Wetlands Wastewater Treatment Systems for Small Users
Including Residences, TVA/WR/WQ-91/2, March 1991, Water Resources
River Basin Oper@tions Resource Development, Tennessee Valley
Authority, Chattanooga, Tennessee.

Peterson, Craig E. and Thomas W. Simpson. Alternative On-site
Wastewater Treatment and Disposal Systems. Department of Crop
and Soil Environmental Sciences and Virginia Cooperative
Extension Service, College of Agriculture and Life Sciences,
Virginia Polytechnic Institute and State University,
Blacksburg, Virginia, 1992.

Report of the Task Force on Septic Recrulations. Institute for
Environmental Negotiations, University of Virginia,
Charlottesville, Virginia, July 1991.

sevebeck, Kathryn 0. and Carolyn J. Kroehler. A Guide to Septic
Systems and Alternatives. Virginia Water Resources Research
Center, Virginia Polytechnic Institute and State University,
Blacksburg, Virginia, 1992.

Sewage Handling and Disposal Regulations. Commonwealth of
Virginia, State Board of Health, Virginia Department of
Health, Richmond, Virginia, May 1989.

Small Wastewater Systems: Alternative Systems for Small
Communities and Rural Areas. U.S. Environmental Protection
Agency, Office of Water Program Operations, Washington, DC,
January 1980.

ACKNOWLEDGEMENTS

The RRPDC would like to acknowledge the assistance it received
in this investigation. Without this assistance, this study could
not have been possible.

The largest thank you goes to the Virginia Department of
Health. Specifically, assistance was rendered by Mr. Don
Alexander, Mr. Roger Cooley, Mr. Dave Effert, Mr. Mike Campbell,
Mr. Duke Price, 'and Mr. Lewis Walker.

Assistance was also received from staff of the Virginia
Polytechnic Institute and State University. This assistance was
provided by Mr. Jay Conta and Dr. Raymond B. Reneau, Jr.

Assistance was also provided by several people from the
private section. This included Mr. Bob Mayer, M.S., P.E., Ms.
Bambi Barnette, Home Builders Association of Richmond, Mr. Ted
Baxter, Gentry Well Works, Mr. Harold Mathews, Mathews Soil
Consultants, and Mr. Peter Books.

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