905R81120
5599 REGION V GUIDANCE . . . .... „,
1 ' . ! • ; j
SITE SPECIFIC NEE:~
DETERMINATION AND ALTERNATIVE, PLANNING
FOR UNSEWERED AREAS..'! J.'. ' £.'G iv] 3-33
I. Objective , . , • , . - ... ,, ,
The objective of this guidance is to clarify fulfillment of the require-
ments regarding the demonstration of need for sewage treatment associated with.
the application of Program Requirements Memorandum (PRM) 78-9, "Funding of
Sewage Collection System Projects," and PRM 79-8, "Small Wastewater Systems."
This guidance is written particularly with respect to the needs of small,
rural communities and the consideration of individual on-site and small scale
technologies. It suggests procedures which may be utilized to minimize the
time, effort, and expense necessary to demonstrate facilities needs. It is
also intended to provide guidance pertaining to the selection of decentraliza-
tion alternatives for a cost-effectiveness comparison. It is intended to
prevent indiscriminate definition of need based upon "broad brush" use of a
sing.le criterion or on decisions unsupported by fact.
The procedure recommended herein may not be the optimum procedure for all
projects. However, compliance with this approach will be prima facie evidence
for the acceptability of the "needs" portion of a proposed plan of study. If
another method is proposed for documenting needs for wastewater facilities, it
is recommended that the grant applicant discuss the proposed approach with
reviewing authorities prior to the submission of the Plan of Study and the
Step 1 grant application.
This guidance is predicated on the premise that planning expenditures
should be commensurate with the cost and risk of implementing feasible alter-
natives for a specific planning area. The guidance further recognizes the
complexity of planning alternative technology. It presents procedures for,
and rationally limits, the amount of detailed site investigation necessary to
determine the suitability of alternative technology for specific areas within
the community, and allows for a degree of risk inherent to limited data
gathering.
II. Goal
The goal of this process is to enable communities to categorize existing
on-site treatment systems into three groups. The groups are those experi-
encing: (a) obvious sewage treatment problems, (b) no problem, and (c)
potential problems representing a planning risk that requires resolution by
the acquisition of original data.
The acquisition of original data as described will support not only
documentation of need but also development of appropriate alternatives and
their associated costs.
U.S. Environmental Protection Agency
Region V, Library
230 South Dearborn Street
Chicago, Illinois 60604
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UjS. Environmental Protection
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III. Criteria for site-specific needs determination
A. Direct evidence that demonstrates obvious problems includes:
1. Failure by surface (breakout) ponding of filter field discharges
can be identified through direct observations, mailed question-
naires, and remote imagery.
2. Sewage backup in residences can be identified through respones
to mailed questionnaires, knowledge of local septage haulers, or
knowledge of local health or zoning officials.
3. Flowing effluent pipes detected by aerial photography, site
visits, knowledge of local officials, or results of mailed ques-
tionnnaires.
A. Contamination of water supply wells (groundwater) by sewage can
be demonstrated by well inspection and sampling and analyses for
whiteners, chlorides, nitrates, fecal coliform bacteria, or
other indicators, and a finding of their presence in concen-
trations which significantly exceed background levels in ground-
waters of the area or primary drinking water quality standards.
Improperly constructed wells or wells inadequately protected
from surface runoff cannot be used to demonstrate an obvious
need. Wells for which construction and protection are unknown
cannot be used to demonstrate an obvious need.
5. Samples taken from effluents entering surface water through soil
that analysis shows to have unacceptable quantities of nutrients
or bacteria.
B. Indirect evidence that indicates potential problems due to site
limitations or inadequate design of treatment systems includes:
1. Seasonal or year-round high water table. Seasonal or annual
water table can be determined by taking transit sightings from a
known lake level, if the dwelling in question is adjacent to a
lake or other surface waters. Elsewhere, Soil Conservation
Service maps may indicate depth to groundwater.
2. Water well isolation distances (depending on depth of well and
presence or absence of impermeable soils). Isolation distances
may be addressed in part by lot size. In cases where a commu-
nity water system is installed or is concurrently planned, this
criterion will not be considered. Lots, including consolidated
lots, which are less than 10,000 square feet in area, will be
assumed to have insufficient isolation distances. However,
before this criterion may be used as areawide evidence, a corre-
lation with results of limited representative sampling which
substantiate water well contamination must be made.
3. Documented groundwater flow from a filter fie,ld toward a water
supply well may override seemingly adequate separation
distances.
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4. Sewage effluent or tracer dye in surface water detected by site
visit or various effluent detection systems. Additional tests
that indicate unacceptable quantities of nutrients or bacteria
in the effluent reaching surface water will establish direct
evidence of need.
5. Bedrock proximity (within three feet of filter field pipe) can
be assessed by utilizing existing SCS soils maps.
6. Slowly permeable soils with greater than 60 minutes/inch perc-
olation rate.
7. Rapidly permeable soil with less than 0.1 minutes/inch percola-
tion rate. Soil permeability may be assessed by evaluating
existing SCS maps.
8. While holding tanks, in certain cases, can be a cost-effective
alternative, for purposes of site-specific needs determination,
a residence equipped with a holding tank for domestic sewage
should be considered as indirect evidence of need for sewage
treatment facilities. Location of holding tanks will be identi-
fied through records of local permitting officials, septage
haulers, or results of mailed questionnaires.
9. On-site treatment systems which do not conform to accepted prac-
tices or current sanitary codes may be documented by owners,
installers, or local permitting officials. This category would
include cesspools, inadequately sized system components (the
proverbial "55 gallon drum" septic tank), and systems which
feature direct discharge of septic tank effluent to surface
water.
10. On-site systems: (a) incorporating components, (b) installed on
individual lots, or (c) of an age, that local data indicate are
characterized by excessive defect and failure rates, or non-
cost-effective maintenance requirements.
Indirect evidence may not be used alone to document the need for
either centralized or decentralized facilities. Prior to field
investigation, indirect evidence should be used to define the scope
and level of effort of the investigations. When the investigations
are finalized, indirect evidence and results of the field work can
be used together to predict the type and number of on-site and small
scale facilities needed in the community. Facilities predictions
form the basis for alternatives development in Step 1 facilities
planning.
IV. Needs determination for unsewered communities
For projects in which the scope of work is difficult to assess during the
Step 1 application, it is recommended that Step 1 be divided into two phases
to more effectively allow estimation of the planning scope and associated
costs. Phase I will consist of a review of existing or 'easily obtainable
data. Phase II will include on-site investigations and representative sam-
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pling necessary to adequately define water quality and public health problems,
identify causes of the problems and predict measures that remedy the problems.
Phase II will also include development of alternatives and completion of the
facilities plans. Both phases should be addressed in the Plan of Study and
grant application. The phases are discussed in greater detail below.
A. Phase I
The review of existing or easily obtainable data may include the
following as appropriate:
1. Review of local well and septic tank permit records. Repair
permits for septic tank systems can provide valuable data on
rates and causes of system failures as well as information on the
repairability of local systems.
2. Interviews with health department or other officials responsible
for existing systems, with septic tank installers and haulers,
and with well drillers.
3. Review of soils maps
4. Calculation of lot sizes
• 5. Estimate depth to water table by reference to lake levels or from
information in soil maps.
6. Aerial photography interpreted to identify suspected surface
malfunctions
7. Leachate detection surveys of ground or surface water
8. A mailed questionnaire regarding each owner's or resident's
knowledge of the on-site system and its performance. Mailed
questionnaires will generate useful data only if well prepared.
Generally, mailed questionnaires should be used only where avail-
able information indicate very low problem rates (to support No
Action alternatives) or where the data indicate very high problem
rates (to support central collection and treatment alternatives).
This preliminary data will be used to categorize developed lots
within the planning area into one of three groups:
1. Obvious-problem
2. No-problem
3. Inconclusive
The"obvious-problem" group consists of those lots where at least one
criterion of direct evidence of a need (specified on Page 2 of this
guidance) is satisfied.
The "no-problem" group consists of theose lots where there is no
direct or indirect evidence to indicate that the present system is
inadequate or malfunctioning.
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The "inconclusive" group consist of developed lots with indirect
evidence of problems. The size of this group and the types of in-
direct evidence associated with it will dictate the scope and level
of effort of field investigations conducted during Phase II.
Typically field work in Phase I will be limited to rapid, community-
wide surveys which require little or no entry onto private property.
Examples are acquisition and interpretation of aerial photography,
field checking of aerial photography interpretations, and shoreline
effluent scans. Additionally, a windshield survey of the community
in the company of health department officials, soil scientists or
other locally knowledgeable persons will help the applicants' repre-
sentative or consultant develop a strategy and cost estimate for
Phase II field investigations.
To facilitate communication of Phase I information, preparation of a
planning area base map at a scale sufficient to locate individual
buildings will normally be helpful. U.S. Geological survey 7.5
minute maps (1:24,000) Soil Conservation Service soil maps (1:15,840)
or local tax maps can be used to inexpensively prepare base maps. At
the end of Phase I, base maps can be used to show developed areas
obviously requiring centralized facilities, individual buildings with
obvious problems and developed areas with indirect evidence of
problems.
Phase I as used here applies principally to needs documentation
activi ties. Obviously, other facilities planning tasks can proceed
concurrently with Phase I.
B. Mid-Course Review
At the end of Phase I, the results of the Phase I effort should be
presented for review and concurrence before proceeding to Phase II.
The Mid-Course Meeting facilities plan review is an appropriate time
for the presentation and discussion of the Phase I results.
The following should be considered at the Mid-Course Meeting:
1. It may become apparent during Phase I that on-site, alternative
technology systems will not be cost-effective for segments of the
community that have obvious needs. In this case, a preliminary
cost estimate for conventional collection and treatment should be
comparer to that for the innovative/alternative treatment solu-
tion. If cost estimates and technical analysis indicate that the
use of alternative technology is clearly not cost-effective,
needs documentation may be terminated for these segments without
proceeding to the on-site investigations of Phase II.
2. The number of lots to be investiaged during the on-site evalua-
tion should be reasonably estimated. If the original estimation
of on-site work included in the Step 1 Grant Agreement is found
to be in error at the end of the preliminary evaluation (Phase
I), a request to amend the grant amount, if necessary, may be
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submitted and a grant amendment expeditiously processed provided
there is concurrence at the Mid-Course Meeting.
C. Phase II Work
Field investigations in Phase II have two primary purposes:
• reclassification of buildings from the "inconclusive" category to
"obvious problem", "no problem" or "potential problem" categories
(defined below)
• development of information needed to predict the technologies and
their costs for^ responding to the community's waste water
problems.
Field investigations can also be designed to accomplish other objec-
tives such as public participation, socio-economic data collection,
etc.
During Phase II previously unrecognised but documentable water quali-
ty and public health problems may be identified, increasing the
number of "obvious problem" buildings. The remainder of buildings
investigated will be classified in the two remaining categories. In
order to do this, representative sampling of site conditions and
water quality in conjunction with partial santiary surveys may be
conducted. Both "obvious" and "inconclusive" problem buildings
should be included in the partial sanitary survey so that reasonable
correlations between site conditions, system usage and system
failures in the community can be made.
"Potential problems" are systems which do not yet exhibit direct
evidence of failure but which can reasonably be expected to fail in
the future. Justifying this expectation must rely on analysis of the
causes for failure of substantially similar systems in the community.
Similarity will be judged on informaton for system usage (number of
occupants and types of sanitary appliances), system design and age,
and verified site limitations (permeability, depth to groundwater or
bedrock, slope, surface drainage, etc.). Buildings in the "inclu-
sive" category whose systems are not similar to any documented fail-
ing system will be included in the "No Problem" category.
This work should be proposed and conducted with the knowledge that
adoption of decentralized alternatives will necessitate complete site
analysis for each building later in the Construction Grants process.
Work should, therefore, be thorough enough that augmentation of the
Phase II work by later studies can be accomplished without duplicat-
ing the Phase II work. The work should also seek the causes of
problem, not just their existence, so that typical on-site and small
scale technologies can be tentatively identified and incorporated
into community alternatives.
Representative sampling of site conditions and water quality should
be carefully coordinated with partial sanitary sifrveys. While the
design of this work will obviously have to be tailored to each com-
munity's unique situation, general guidance is provided here.
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1. Representative Sampling
a. Seasonal or permanent high water table. Soil surveys and
comparison with known lake levels reviewed in Phase I may not
be accurate enough to explain specific on-site system problems
or to carefully delineate groups of lots where high water
table is a serious site limitation. Soil to a depth of 5 or 6
feet on or adjacent to suspect lots can resolve such uncer-
tainties. Where seasonal high water table is suspected and
work has to be conducted during dry weather, a soil scientist
with knowledge of local soils should be involved.
b. Groundwater Flow. The safety of on-site well water supplies
and springs on small lots may depend on the rate and direction
of groundwater flow. Estimating the effects of effluents on
surface waters may also require such information. Methods
which indicate groundwater flow characteristics should be
selected and supervised by qualified professionals. Generally
this work in Phase II will be limited to evaluation of well
logs and other available data and of rapid surveys in special
areas such as lakeshores. Exceptions for more intensive work
will be considered where uncertainties about sources of well
contamination need to be resolved for specific lots or groups
of lots.
c. Well water contamination. Where lot sizes are small or soils
are especially permeable, collection and analysis of well
water samples at residences included in sanitary surveys
should be considered. Parameters that can be evaluated as
pollution indicators include, but are not limited to: chlo-
rides, nitrates, phosphates, fecal coliforms, surfactants,
whiteners and other readily detectable constituents inherent
to domestic waste water. No well samples should be collected
from wells that are improperly protected from surface runoff
or other non-wastewater sources. An inspection report should
accompany each well analysis.
d. Shallow groundwater contamination. In areas with drainfield
to groundwater separation distances less than state standards,
shallow groundwater at or near affected water bodies (lake,
stream, unconfined aquifers) should be sampled before aban-
doning on-site wastewater systems on the basis of high water
tables. Discrete samples may be collected during checks of
high water tables for analysis of conventional parameters as
listed above. Alternatively, as rapid survey techniques are
perfected, they may be more appropriate.
e. Soil permeability. If very slow or very rapid soil per-
meability is suspected of contributing to surface malfunc-
tions, backups or groundwater contamination, soil characteris-
tics can be evaluated by augcring to 5 or 6t foot depth on or
adjacent to selected lots. Usually, descriptions of soil
horizons by depth, color, texture arid presence of mottling,
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water or bedrock will suffice. Percolation tests for existing
systems will be necessary only in extraordinary circumstances.
2. Partial Sanitary Surveys
It is not the intent of needs documentation to finally identify
each and every wastewater problem in a community. It is not
cost-effective to select appropriate technologies for each
property in Step 1.
Therefore, Phase II sanitary surveys will include only a suf-
ficient number of existing buildings to confirm the level and type
of need present, and to predict the type and approximate number of
measures to correct the problems. Correlation of partial sanitary
survey data, representative sampling, and indirect evidence of
system problems should be sufficient to meet these objectives.
Sanitary surveys should include for each building:
• an interview with the resident to determine age of the build-
ing and sewage disposal system, design and location of the
sewage disposal system, system maintenance, occupancy of the
building, water using appliances, use of water conservation
devices, and problems with the wastewater system.
* an inspection of the property, preferably in the company of the
resident, noting location of well, septic tank, soil absorption
system, pit privies and other sanitary facilities; lot dimen-
sions; slope; roof and surface drainage; evidence of past and
present malfunctions; and other relevant information such as a
algae growth in shoreline areas.
» any representative sampling that is appropriate to the site and
that can be scheduled concurrently.
• preliminary conclusions on maintenance, repairs, applicable
water conservation methods, and types and location of replace-
ment or upgrading for existing wastewater systems.
As a rule of thumb, the number of buildings surveyed should not
exceed 30 percent. Where Phase I data is very incomplete, the
buildings may be selected on a random basis and should include a
minimum of 20 percent of existing buildings. Where buildings with
obvious problems and areas with indirect evidence of problems are
well delineated in Phase I, the surveys can be better focused,
perhaps requiring fewer buildings to be surveyed. From 10 to 50
percent of buildings having obvious problems should be surveyed.
In areas with indirect evidence of problems, 20 to 30 percent
would be sufficient. Areas with neither direct nor indirect
evidence may be surveyed where system age, unusual occupancy
patterns or especially severe consequences of system failure so
indicate. ,
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V. Planning of Alternatives
In unsewered, low housing density areas, PRM 78-9, "Funding of Sewage
Collection System Projects", puts the burden of proof for need and cost-
effectiveness of sewers on the applicant. The four criteria outlined in PRM
78-9 for eligibility of collector sewers are:
• need
• cost-effectiveness
• substantial human habitation in 1972
« 2/3 rule
Figure 1 portrays the relationship of these criteria in a decision flow
diagram.
Definition of need by the approach outlined above will address the first
criterion. Estimating cost-effectiveness will typically require two steps:
determining the feasibility of non-sewered technologies for remedying obvious
and potential problems, and comparing the present worth of feasible non-
sewered technologies with the present worth of sewers.
The determination of feasibility for non-sewered technologies should not
be limited to standard septic tank/soil absorption systems. Where lot sites,
site limitations or excessive flows can be overcome by alternative techno-
logies, these must be considered. To the extent that the needs documentation
results show that existing soil absorption systems smaller than current code
requirements can operate satisfactorily, sub-code replacements for obvious
problems should also be considered if lot site or other restrictions preclude
full sized systems.
The use of needs documentation results in developing alternatives should
be guided by methods selected to design the Phase II field investigations. If
sanitary surveys and representative sampling were conducted on a random basis,
then the types and numbers of technical remedies should be projected for the
entire area surveyed without bias. However, if efforts were focused on
identified problem or inconclusive segments of a community, then predictions
from the data should be made for surveyed segments only. Real but unre-
cognized problems in "no problem" areas can be accounted for by assuming
upgrading or replacement of existing systems in these areas at frequencies
reasonably lower than surveyed segments.
Infeasibility of remedying individual, obvious problems on-site will not
be sufficient justification for proposing central sewering of a community or
segment of a community. Off-site treatment can be achieved by pumping and
hauling and by small scale, neighborhood collection and treatment systems.
The choice between these approaches should be based upon a cost comparison
which includes serious flow reduction measures in conjunction with any holding
tanks.
Segment by segment cost-effectiveness comparisons will be required only
for those segments where new facilities for off-site treatment are proposed.
Community-wide cost estimates for upgrading or replacement of on-site systems
in decentralized areas will generally be adequate for description of Proposed
Actions pending detailed site analysis and cost estimates for each building in
Step 2.
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Field work necessary to thoroughly evaluate the condition of individual
on-site systems and to select technology for necessary upgrading or replace-
ment is generally to be viewed as Step 2 or Step 2 + 3 work. Typical field
work for this level of analysis includes completion of the sanitary survey
and, as appropriate to each building, installation and monitoring of water
meters, inspection of septic tanks, rodding house sewers and effluent lines,
probing or limited excavation of soil absorption systems for inspection, and
other measures listed above for representative sampling. Construction of
on-site replacements and upgrading may proceed in tandem with this site
specific analysis provided:
• state and local officials concur (their prior concurrence might
be limited to standard systems),
« contract language allows for flexibility in the facilities to
be constructed,
• property owner concurrence with the selected alterations is obtained,
and
• additional cost-effectiveness analysis to support technology selection
is not necessary.
Necessary state and local agency approval of off-site, non-standard, or
owner-protested facilities or those requiring additional cost analysis would
optimally proceed on a segment-by-segment basis to minimize the time between
technology selection and construction.
The establishment of a management district's authority to accept re-
sponsibility for the proper installation, operation and maintenance of indi-
vidual systems per 40 CFR 35.918-1(e) and (i) should be completed before award
of Step 2 or Step 2 + 3 grants. Development of a management district's pro-
gram for regulation and inspection of systems must be completed before a Step
3 grant award or before authorization to proceed with construction procurement
is granted under a Step 2+3 grant.
VI. Public participation
The following comments are intended to demonstrate how this guidance
relates to the standard requirements for public participation. It is not all
inclusive.
A. Although mailed questionnaries have limited utility for needs docu-
mentation, they can serve as useful public participation tools. A
useful "mailing list" may include all owners of residences within
unsewered areas in the planning area and other interested and
affected parties.
The requirement for consulting with the public set forth in 40 CFR
35.917-5(b)(5) will be considered satisfied if questionnaires are
submitted by individuals on the "mailing list."
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¥ •'
B. The public meeting required by 40 CFR 35.917-5(b) (6) provides an
opportunity for property owners to be informed of whether or not
they have been found to need wastewater treatment facilities. During
the meeting they can respond to the consultant's determination of
their need status. A map with each lot designated as no-need,
obvious-problem, or inconclusive would be helpful for public under-
standing. This meeting could be conveniently scheduled at the end of
Phase I.
C. Partial sanitary surveys conducted during Phase 2 of needs documen-
tation offer an excellent opportunity to gain public input provided
surveyors are adequately informed about the project or can refer
difficult questions to a knowledgeable person for immediate re-
sponse.
D. The final public hearing required by 40 CFR 35.917-5 should be sche-
duled at the end of facilities planning. At this public hearing a
map showing service areas for grantee supervised decentralized
technologies will be displayed. Within service areas, tentatively
proposed methods of treatment and disposal for individual developed
lots will be available to the lot owners. It should made clear to
the public that site investigations conducted in Steps 2 or 3 may
result in adjustments to the proposed treatment and disposal methods
for individual lots.
,f,
Region V, Libra:/
SOUtn Dearborn
go, Illinois 60604
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