Haw-To Manual:
Update and Enhance Your Local
Source Water Protection Assessments

  The U.S. Environmental Protection Agency (EPA) prepared this Manual to help you update and enhance your
  source water protection assessment.  This document does not impose legally binding requirements on EPA,
  states, tribes, or the regulated community, and it may or may not be applicable to a particular situation
  depending on the circumstances. Updating and/or enhancing a source water protection assessment is
  voluntary.  Source Water Protection Partners (public and private individuals/organizations interested in
  protecting source waters) who choose to enhance and/or update assessments, retain the discretion to adopt
  none, any, or all of the approaches described in this document, on a case-by-case basis. EPA may change
  this Manual in the future.  To obtain additional copies of this document, contact the Safe Drinking Water
  Hotline at (800) 426-4791.

Office of Water
September 2006


   A. The Purpose of This Manual	3
       Who Is the Biggest Beneficiary of an Updated Assessment?	4
   B. Why Your State Assessment Could Benefit From Updating	4
       State Assessments May Contain Limited Data	4
       State Assessments Address Only Most Significant Threats	4
   C. Additional Reasons For Updating/Enhancing Assessments	4
   D. The Role Played by Source Water Protection  Partners	5
   E.  Initiating Action and Building Support	5

   A. How Source Water Protection Partners Can Update and Enhance Delineations	6
       Partners Can Improve Delineation of Ground-Water Supplied Source Water
         Areas Through a Variety of Methods	6
       Partners Can Improve Surface-Water Critical-Area Delineation	8
          Arbitrary RodiaI Distanee	8
          Strea m Ti me -of-Trave I Dista nee	8
          Buffer Zones	9
          Ti me- of-Travel Area	9
       Partners Can Improve Ground-Water/Surface-Water Conjunctive Delineations	1 0
   B. Reasons to Update and Enhance Contaminant Source Inventories	1 0
       How States Developed the Contaminant Source Inventory	1 0
       The Contaminant Source Inventory as an Opportunity to Enhance an Assessment	1 0
          Li mited I nventory	11
          Changes With Time	11
          Emerging, and Other Unregulated, Contaminants	11
       Contaminant Source Inventory Methods Used by States	1 1
       Partner Actions to Update/Enhance Contaminant Source Inventories	1 2
          Supplementing Initial Inventory with Local Data	13
          Adding Information to Existing Data Sources and Obtaining
            Additional Information From Data Gatherers	13
          Ascertaining That All Significant Potential Contamination Sources are Identified
            and Located	14
          Evaluating Implementation and Effectiveness of Existing
            Protection Strategies 	14

          Performing Other Activities	15
          Encouraging Participation of Source Water Protection Partners	15

   A. Critical Factors to Consider When Determining the Susceptibility of the Public Water Supply	1 6
       Presence of Potential Contaminant Sources and the Impacts of Contaminant
          Characteristics and Management Practices	16
       PhysicaI I ntegrity	17
       Sensitivity of the Natural Setting	1 7
       Presence of Natural Contamination in the Source Water	1 7
   B. How States Combined These Factors to Arrive at a Susceptibility Determination	1 8
   C. The Intra-system and Inter-system Approaches to Susceptibility Determination	1 8
   D. When and How Source Water Protection Partners Can Recalculate/Revise the
        Susceptibility Determination	19




This is a general document that is applicable
across the country.  States may have similar docu-
ments or information targeted specifically to their
own Source Water Protection Partners.  The contact
information for the source water assessment and
protection agency in each state can be found at:

A.  The Purpose of This Manual

This manual is intended to help Source Water
Protection (SWP) Partners protect the raw sources
of their drinking water from Potential Contaminant
Sources (PCSs).  (For additional guidance, Source
Water Protection Partners might also refer to the
State Source Water Assessment and Protection Pro-
grams Guidance [1 997 Guidance], EPA 81 6-R-97-
009; (http://www.epa.gov/safewater/

Source Water  Protection Partners involved in SWP
include: community leaders, local officials, local-
agency and public water supply personnel, com-
munity-based  environmental groups, watershed
and public organizations, farmers and businesses,
concerned citizens and state source water  protec-
tion implementing agencies. This manual provides
the reasons for updating your state's Source Water
assessment, explains how Partners are major play-
ers, and describes opportunities for enhancing/up-
dating your state's assessment1 with:

     More accurate delineations.
     Contaminant Source Inventories (CSIs)
      updated with local information.
     Modified or recalculated Susceptibility
      Determinations (SDs).
Information collected and analyzed by states across
the country through source water assessments
("assessments"), are used to help determine priori-
ties needed to protect local  drinking-water sources
of each Public Water Supply (PWS). The assess-
ments, performed under the Safe Drinking Water
Act section 1453, were required as a one-time
effort.  The information from a local assessment
can be used by SWP Partners to develop or expand
activities to prevent  contamination of local sources
of drinking water.

States were required to conduct an assessment
for the source of supply for  every PWS - from the
roadside diner's well to the river providing drinking
Public water system's no trespassing sign.
1 States that regulate source water and/or wellhead protection generally require periodic review and revision of the protection plans. In
these states, contact the state implementing agency to ensure that any revision will meet their requirements. In states where source water
and/or wellhead protection is voluntary, check with the state to determine whether or not supplying them with enhancement results would
prove useful. Asking the state for technical assistance might be helpful, but Partners need to be aware that the state's capacity to provide
it is limited.

www.epa.gov/safewater                                                                                      3

water for a major metropolitan area.  Most assess-
ments have been completed. However, because
states had a limited timeframe, baseline assess-
ments, which states completed for all community
water systems using readily available information,
might be improved  by additional data. In addition,
there may have been changes in land uses or other
activities that would affect the baseline assessment.
In such cases, opportunities exist for SWP Partners
to add local data to the state's initial assessment.

Who Is the Biggest Beneficiary of an Updated
The more comprehensive and current an assess-
ment, the more it is likely to be useful for providing
a basis for regulatory flexibility under current or
planned rules under the Safe Drinking Water Act
and state laws (e.g., waivers or alternative monitor-
ing schedules).
   Economic savings resulting from such flex-
     ibility could benefit many public water
  systems, particularly if the assessments are
            updated periodically.
B.  Why Your State Assessment
    Could Benefit From Updating

Your state was probably only able to complete a
baseline assessment for all community water
systems. These assessments may be short of infor-
mation, particularly local data, and do not reflect
changes in land use or other activities that may
have occurred since the assessments were com-
pleted. This is because your state, like all states,
had only 3 ]/2 years to complete assessments for all
of its PWSs.

State Assessments May Contain Limited Data
Many states had hundreds or thousands of assess-
ments to complete and needed to budget time and
resources in order to meet the required deadline.
Most states relied primarily on readily available in-
formation. Depending on the state's priorities and
resources, the depth of detail and technical com-
plexity of the assessments varied across the Nation
and within some states.  For example, according
to New York's priority-setting process, assessments
for systems that serve large populations and those
that have existing contamination problems were
conducted in greater detail than those for other
4                                    Hoiv-To Manual:
Other states used less rigorous methods for con-
ducting assessments for small or transient systems,
or for systems in certain hydrogeologic settings
such as confined aquifers. Where states asked
water systems or local government agencies to
conduct all or part of the  assessments, the  level of
detail and thoroughness likely varied depending
on the local resources and expertise available to
complete the work.

State Assessments Address Only Most
Significant Threats
Although state and federal regulations focus on the
large, obvious water dischargers, sometimes it's
the  less obvious unregulated contamination sources
that cause a community's water supply to become
contaminated. Unregulated sources such as con-
taminated runoff from communities and agricul-
tural activities can  also transport contaminants to a
water source.
   There are hundreds of sources that could
    potentially contaminate a community's
   water supplies, resulting in considerable
   expense to the community. For instance,
   PCSs could include: an accidental release
   from a town's sewage treatment plant up-
   stream, a leaky backyard heating-oil tank,
   the rupture of a gasoline pipeline near a
   community well, or a small hog farm dis-
   charging excess waste to a local stream.
C.  Additional Reasons For

Updating or enhancing assessments is a natural
next step because:
     Many states adopted an iterative approach
     to source water assessment and protection;
     promoting local enhancement/updating of
     assessments supports both iterative state
     source water assessment plans and source
     water protection implementation.
     Completed assessments provide, for this first
     time in many cases, a platform from which
     to work.
     Time constraints associated with initial dead-
     lines have passed.

     Land use activities, and hence potential con-
     taminant sources, change over time.
     Additional data sources may now be avail-
     able to support enhancements and updates.

Enhanced/updated assessments can:
      "Ground truth" initial-assessment results,
      especially if they are not consistent with lo-
      cal knowledge or do not reflect site-specific
     Help define  priorities for protection activities.
     Result in improved or maintained high, raw-
     water quality and  its attendant cost savings.
     Provide greater accuracy and facilitate imple-
     mentation of protection measures.

D.  The Role  Played by Source
    Wafer Protection Partners

EPA encourages Partners to build on the core
program developed by the state, by updating and
enhancing the initial assessment with additional
local data and/or more rigorous approaches to
make assessments meaningful tools for protection

Partners can gather local data on PCSs that may
not be available to state agencies, collect addition-
al information on  PCSs  that may threaten the water
supply, create a comprehensive inventory of poten-
tial threats to the water supply, and create a more
detailed and thorough local assessment that can
be used to more accurately identify priority protec-
tion needs. Once these priorities are identified,
SWP Partners can begin working on a balanced
and justifiable plan to manage threats and prevent
contamination of the drinking-water supply.

The initial assessment may have provided recom-
mendations for actions that SWP Partners could
take to protect the source water. In such cases, the
assessment may be enhanced as recommended,
to help community leaders begin to plan and
implement a protection program based on the
assessment's findings, and to adapt the protection
program overtime.

f.  Initiating Action and Building

In some cases, community leaders will take the
initial action and engage other SWP Partners in
enhancing/updating assessments.  In other cases,
the initial action will be taken by local organiza-
tions such as a watershed  group or the League of
Women Voters.

Broad support for protecting the drinking-water
source can be built if a wide cross-section of SWP
Partners is engaged in the assessment and protec-
tion process.
                                                          Public involvement educates individuals
                                                        about how their own actions may impact the
                                                                community's water source.
                                                      When a broad array of local officials, youth and
                                                      community groups, businesses and other inter-
                                                      ested community members become informed and
                                                      engaged in the process of protecting the water
                                                      source, obstacles can be overcome and a stage set
                                                      for the implementation of a protection program.  A
                                                      safe and reliable source of drinking water is  im-
                                                      portant to everyone, and creative and cooperative
                                                      approaches can be developed once community
                                                      leaders join  other SWP Partners to work together to
                                                      periodically  enhance and update assessments.
Source Water Protection Partners inputting locations of potential
contaminant sources into a computer. Photo by Stephen Ausmus;
U.S. Department of Agriculture, Agricultural Research Service

This section is intended to help Source Water
Protection (SWP) Partners look closely at the meth-
ods and techniques used in conducting their local
assessment and to help determine if the assessment
should be updated or if new information is avail-
able that could enhance the detail and accuracy of
the current assessment.

The actual work of enhancing/updating assess-
ments can be performed not only by public-water-
supply (PWS) and state/local-government employ-
ees, but also by other Partners.  For example, with
training, volunteers such as local civic organiza-
tions, youth groups or retirees can provide valuable
assistance in gathering and consolidating local
data to enhance the assessment. Communities
may be able to reach an agreement with the state
implementing agency to receive training  on per-
forming the elements of interest in the assessment
enhancement/updating process. Although Partners
might ask the state for technical assistance, they
should be aware that the state's capacity to provide
it is limited.

A.  How Source Water Protection
     Partners  Can Update and
     Enhance  Delineations

Partners Con Improve Delineation of
Ground-Water Supplied Source Water
Areas Through a Variety of Methods
The states employed a variety of methods for
delineating the source water areas (SWAs) of PWS
wells. Some of these methods are more scientifi-
cally based than others, and in many communities
opportunities exist to refine the initial delinea-
tion2. Partners should consider employing a more
sophisticated, ground-water delineation method,
particularly when (1) a more accurately delineated
SWA is desired  in order to target or justify SWP
measures and/or (2) the well is located in a karst,
or other hydrogeologically complex, setting and
the initial delineation method was not hydrogeo-
logic mapping. All methods, except arbitrary fixed
radius and hydrogeologic mapping, can  provide a
ground-water travel-time distance to a well.

The order of increasing accuracy and sophistication
of the methods is as follows:
    Arbitrary fixed radius
    Calculated fixed radius
    Fixed variable shapes
    Analytical methods (such as the uniform flow
    Hydrogeologic mapping
    Numerical flow or flow-and-transport com-
     puter models
Brief descriptions of these methods are provided in
Appendix A.

Two methods could be combined. For example, the
boundary selected could be the closer of the hydro-
geologic boundary and the 1 0-year ground-water
travel-time boundary determined by flow modeling.
Partners might also want to consider expanding the
SWA by selecting a larger fixed radius or a longer
ground-water travel time to the well.
2 Partners are advised to contact the appropriate municipal, county and, where appropriate, state authorities, when enhanced or updated
delineation yields revised source watch protection area boundaries.
6                                   How- To Manual: Update and Enhance Your Local Source Water Protection Assessments

 Fixed-radius methods tend to overprotect a well in
 the direction of ground-water flow and underpro-
 tect in the direction opposite to ground-water flow.
 Communities/PWSs could upgrade their delineation
 approach and, where it would add accuracy, take
 advantage of the user-friendly Wellhead Analytical
 Element Model (WhAEM), or other computer-mod-
 eling programs.

 Enhancing ground-water delineations requires
 more technical expertise than enhancement of
 other aspects of the assessment.
    If Partners revise a delineation, then they
    likely will need to revise the contaminant
  source inventory and recalculate the results
       of the susceptibility determination.
Again, in states where Source Water Protection and/
or Wellhead Protection are required, state regulations
generally have requirements for periodic review and
revision of the protection plans. In these states, Part-
ners should consult with the implementing agency to
ensure that enhanced delineations will meet state re-
quirements.  In states where Source Water Protection
and/or Wellhead Protection are voluntary, Partners
may check with the state early in the enhancement
process, and  provide results if the state would like to
have them. The state implementing agency may be
able to provide  information on appropriate delinea-
tion methods, or information on why the original
method was chosen.  In general, simpler methods
had been selected because of the lack of information
necessary to perform more sophisticated analyses,
and because  of the lack of funding to collect addi-
tional information and support technical staffers who
could perform more complex analyses.

The use of any delineation method except the ar-
bitrary fixed radius requires some hydrogeologic
knowledge, (see Appendix A)  However, moving up
from the arbitrary fixed radius to the calculated fixed
radius method is generally not costly and needs only
minimal input from a hydrogeologic expert.  Thus,
for communities in those states that have employed
the arbitrary fixed  radius method, recalculating the
SWA with the calculated fixed radius method may
be fairly straightforward.  The fixed variable shapes
method likely will require  a moderate amount of in-
put from a hydrogeologic expert, who will be needed
to supply the ground-water flow directions and the
values of the hydrogeologic parameters.

Hydrogeologic mapping can include improved
information about natural sensitivity and/or about
underground barriers to ground-water flow. Such
information needs should  require input from
technical experts. Incorporating sensitivity and/or
barrier information likely will increase the accuracy
and protective ness of the delineation of the SWA
for a well. Partners have the opportunity to delin-
eate entire aquifer outcrop areas as sensitive areas
and are encouraged  to identify karst features, such
as sinkholes, as potential contaminant sources

The Environmental Protection Agency's WhAEM  nu-
merical flow computer model  has been modified to
be more  user-friendly. Some states have used other
sophisticated computer models to perform delinea-
tions.  The use of any computer model requires the
services of a technical expert;  simple-to-use mod-
els require, at a minimum, expert opinion on flow
boundaries and parameter values.  Upgrading to
computer modeling with all but the simplest-to-use
models is probably realistic only for moderate to
large  PWSs.

It could become costly for  a community to hire out-
side experts to enhance a  delineation,  depending
on the rates charged and the  method to be used.
However, there are several sources  of potential as-
sistance available; some may provide low-cost or
free services to communities.  Technical assistance
resources might include:
      State SWP implementing agency (http://www.
      EPA regional office (http://www.epa.gov/
      saf ewate r/so u rcewate r).
      US Geological  Survey District Office (http://
      US Department of Agriculture Cooperative
      Extension System Office (http://www.csrees.
      State geological survey; the simplest link is
      through the Association  of American State
      Geologists (http://www.gsa.state.al.us/).
      State Rural Water Association wellhead and
      source water programs (http://www.nrwa.
      Local health department.

      Professors or graduate students at a local
      college or university in the departments of
      Environmental Studies, Geology/Hydrology,
      Engineering (civil, hydrologic or
      Hydrogeologists, engineers or environmental
      professionals  in the community.
      Hydrogeologic and environmental consulting

Partners Can Improve Surface-Wafer
Critical-Area Delineation
All states delineated the SWA as the entire water-
shed upstream  of a surface-water intake up to the
watershed boundary or to the state boundary, if it
is closer. Because some watersheds are very  large,
states frequently segmented them, identifying a
smaller "critical area" for higher-priority assess-
ment.  Critical areas were used solely to determine
the intensity of the contaminant source  inventory
(CSI) and as one of many factors in determining
Reservoir catchment area. Photo by Tim McCabe, USD A Natural
Resources Conservation Service.

A more detailed CSI was usually conducted in the
critical area rather than in the rest of the water-
shed, because contaminants released in this area
are more likely to reach and contaminate surface
source water. Areas outside the critical area were
inventoried for larger potential contaminant sourc-
es, those within the critical area for all potential
contaminant sources, and the results were analyzed
for susceptibility.
States generally selected one of four general
types of critical-area delineation approaches:  (1)
a stream time-of-travel distance upstream of an
intake; (2) an area defined by an arbitrary radial
distance either around, or uphill of, the intake; (3)
a buffer-zone setback, and (4) a stream time-of-
travel area.  Some states used a combination of
these delineation approaches.
   The primary reason to update the delinea-
   tion of a critical area is that the delineated
   area was not large enough to incorporate
   significant potential contaminant sources.
As examples, some states have not included buffer
zones along upstream tributaries and, perhaps with
rare exception, states have not incorporated land
area into a stream time-of-travel delineation. Ad-
ditionally, actual monitoring data  may indicate that
sources of contaminants in surface waters in the
SWA may lie outside of the current critical area.

Partners might be particularly interested in expand-
ing stream buffers (1) where buffers only extend a
few hours stream travel  time upstream of an intake,
or (2) along streams where the selected  delinea-
tion  method was a stream travel-time distance and,
hence, no buffer exists.

Partners should consider expanding existing critical
areas to include as much of the watershed as pos-
sible in  order to expand the CSI.  This will facilitate
development of better protection programs.

Arbitrary Radial Distance
The area that is defined with the arbitrary radial
distance method is bounded by a circle centered at
the water supply intake, or by the upstream half of
that  circle. The radius of the circle is defined arbi-
trarily or by factors unrelated to hydrology.

Stream  Time-of-Travel Distance
The stream time-of-travel distance approach
defines  the length  of the stream, above an intake,
through which a particle of water  will travel in a
state-defined time period.  (Some states use this
approach specifically for transportation routes
and  other facilities with the potential to spill con-
taminants directly into a stream. This approach is
particularly useful for setting up contingency plans
with local  law enforcement and with facility man-

agers.) However, unless combined with a buffer
zone, this approach does not have an associated
land area and so, no preferentially intensive CSI is

Buffer Zones
Partners may want to  enhance SWAs by expand-
ing buffer zones to include more of the PCSs that
are near the source water. Expanded buffers are
helpful if Partners believe that the original buffers
exclude PCSs that could contaminate the source
water. Because overland travel time after a moder-
ate to heavy rain can  be quite short, contaminants
released from PCSs could quickly reach the source-
water stream or body. Although the United States
Department of Agriculture has technical assistance
for calculating buffer  width to help protect surface
water from  nutrients,  there is no hydrologic ba-
sis for other buffer setbacks or for time-of-travel
distance upstream. However, as a general rule of
thumb, "bigger is better". When considering ex-
pansion of buffers, Partners should consider factors
such as: costs, availability of staff and/or volun-
teers, the hydrogeologic/hydrologic setting, and the
CSI that will be performed.

Many states delineated buffer zones ("setbacks")
along stream banks,  upstream  of PWS intakes, to
designate critical areas.  Many of these states chose
to use the minimum 1,000 ft width approvable  by
EPA.  The upstream extent of these buffers varies by
state, as does whether or not upstream tributaries
also have buffers delineated. Some states define
the upstream limit of  the setback  by employing a
fixed  distance or a state-selected, average-stream-
flow travel time, such  as  5 hours, perhaps associ-
ated with the response time needed to respond  to a
spill into the stream.

T/me-of-Trave/ Area
Source Water Protection Partners may want to
enhance SWAs by expanding them to the area
defined by the Time-of-Travel Area approach.  This
creative approach is based on a pre-selected travel
time, applied to not only the flow of the stream, but
also to the travel time of overland flow.  States can
use any travel time that they choose, such as the
time needed to respond to a spill. This approach
leads to a "leaf-shaped" region, whose boundary
contains all  the area that drains to an intake within
the state-specified travel  time.   Figure 1  depicts an
area defined by a 4-hour stream  travel time.  A
very similar approach is used by the state of
Figure 1: Diagram of area defined by the 4-hour stream travel

A modification of this  method, shown in Figure 2,
yields a larger, more easily calculated  SWA.  Figure
2 depicts an area defined by the distance traveled
in 4 hours, ending at the intake, by water in the
fastest flowing stream. The 4-hour distance is ap-
plied not only to the fastest flowing stream, but also
to all other streams' lengths  and overland travel
paths ending at the water supply intake.
Figure 2: Area defined by 4-hour travel time of fastest stream or
www. epa.gov/safewater

Partners Can Improve Ground-Water/Surface-
Water Conjunctive Delineations
In many places, water moves routinely between
a surface-water source such as a river, stream or
lake, and the underlying and adjacent ground
water.  Wells that are located within river flood-
plains often draw part of their water from the
rivers.  Similarly, in many places for at least part of
the year, much or most of a stream's flow results
from ground water that recharges the stream. The
US Geological Survey estimates that about 40% of
stream flow nationwide comes from ground water
discharging into streams.

"Conjunctive delineation" was recommended in
the 1 997 Guidance for PWS wells withdrawing
from where the quality of a drinking-water source
is strongly influenced by both ground-water and
surface-water sources. Such a delineation includes
both the surface-water and the ground-water areas
that could contribute water and pollutants to the
drinking-water supply. Conjunctive delineation
results  in a delineation of both a SWA for the well
and the watershed  area upstream of where the
well's SWA intersects the stream. An inventory of
PCSs should be conducted  in both the surface-wa-
ter and the ground-water areas. Remember that
changing the delineated area of a well  may also
alter the conjunctively  delineated SWA.

If a state did not initially perform a conjunctive
delineation, and there is a  reason to believe that
a PWS  well is influenced by both ground water
and surface water (for example, if surface-water
contaminants are present in a ground-water sup-
ply),  SWP Partners should consider discussing the
possibility of conducting a conjunctive delinea-
tion.  As stated earlier, states where Source Water
and/or Wellhead Protection are required under
state regulations generally  have requirements for
periodic review and revision of protection plans.  In
these states,  SWP Partners should ensure that their
process meets state requirements.  In states where
Source Water and/or Wellhead Protection are
voluntary, it would  be a courtesy to check with the
state and provide the results of the enhancement, if
the state has the capacity to use it.
B.  Reasons to Update and Enhance
    Contaminant Source Inventories

How States Developed the Contaminant
Source Inventory
As with other parts of the Source Water Protection
program, states were given flexibility in design-
ing the CSI methods to be used.  This resulted in a
variety of inventory methods in the SWP programs
among different states.  Also, a state may have
used a variety of inventory methods, each method
being based on the size or type of water system.
For instance, the inventory for a well serving a
roadside public drinking fountain  might consist of
only the PCSs of such contaminants  as bacteria
and nitrates, that is, those contaminants that could
make someone sick with a limited consumption
of the water. By comparison, the inventory for a
water system serving a metropolitan area would
include all types of regulated drinking water con-
taminants, and the inventory could extend up to,
or perhaps into, upstream states.  Many states
conducted inventories primarily using databases of
regulated activities, supplemented with additional
information such as land use.  States may or may
not have included local information  in the initial
effort, depending on such factors as availability, lo-
cal participation, and state resources to gather this

States included in their inventories potential sources
of chemicals regulated under the Safe Drinking
Water Act (contaminants with a maximum contami-
nant level, contaminants regulated under the En-
hanced Surface Water Treatment Rule, and the mi-
croorganism Cryptosporidium). In addition, states
were invited to include other contaminants that are
not federally regulated, but which the state had de-
termined may present a threat to public health.  For
instance, New York included pathogenic viruses as
a contaminant of concern in its assessments, even
though the federal government does not currently
regulate them.

The Confam/nanf Source  Inventory as an
Opportunity to Enhance an Assessment
The CSI is  an opportunity for SWP Partners to
enhance an assessment with local information.
EPA encourages Partners to invest the time and
resources in contributing additional  information
to the inventory, since this will ensure that the list
of PCSs is as comprehensive as possible.  For

example, information on abandoned waste sites,
industrial septic tanks, home fuel oil tanks, small
livestock operations, golf courses and other land
uses or activities that could release pollutants to the
water supply, could be added to the initial inventory
through local efforts.  Another approach to  identify-
ing contaminant sources is performing, or identify-
ing studies that have performed, reverse-tracking
computer modeling of contaminants causing drink-
ing water violations.

In addition, local involvement can greatly increase
public knowledge of the resource and generate
support for activities to protect the community's
source water.  Lastly, if new wells or intakes  have
come online, or wells/intakes have been relocated,
a complete source water assessment should be

There are three primary reasons for updating and
enhancing contaminant source inventories:  limited
inventory; changes with  time; and emerging, and
other unregulated, contaminants.

Limited Inventory
To enhance a limited inventory: because of the
limited  time available to states, many chose to
perform limited CSIs. Even those states that per-
formed more extensive inventories  may have PCSs
that were not identified or field-verified, or that
came into existence after the initial assessment was

Source  Water Protection Partners particularly should
consider enhancing the  initial inventory if:
     The inventory is based solely on information
      from state or federal databases (no local data
      were used).
     Primary categories of PCSs are not invento-
     Locations of PCSs  are not verified in the field.
     Specific PCSs are not identified, only the PCS
      category is  mentioned.
     The community has additional information
      and data to enhance the inventory.
     The hydrogeologic setting is sensitive/vulner-
             THIS SITE
Sign stating change in land use from farming to commercial. Photo
by Lynn Betts, USD A Natural Resources Conservation Service.

Changes With Time
To reflect changes with time: EPA encourages SWP
Partners to regularly update CSIs to reflect chang-
ing land use and activities, and/or PCSs introduced
into the SWA by virtue of a change in the delineat-
ed boundary of a SWA for a well, or a critical area
fora surface-water-supplied intake.

Emerging, and Other Unregulated,  Contaminants
Partners might want to perform a CSI to address
emerging contaminants.  Some system manag-
ers are becoming particularly concerned about
Pharmaceuticals, chlorophyll A and caffeine. When
these are found in drinking water, it is likely that
they have come from an upstream waste treatment
plant. Water system managers should be alert to
this emerging issue.  In addition, some constituents
on the Contaminant Candidate List have risen to
national attention; these, too, might  be consid-
ered when updating/enhancing assessments. EPA
recommends that all relevant unregulated contami-
nants be considered in an assessment update.

Confam/nanf Source Inventory Methods Used
by States
Because states used an array of methods to con-
duct their CSI, the inventories varied  considerably
in level of detail  and comprehensiveness.  Most
states conducted database searches  of regulated
facilities as an initial step  in the inventory. In some
www. epa.gov/safewater

states, such database searches comprised the
entire inventory. In other states, a more detailed
investigation on the ground for some or all PWSs,
revealed considerable information that may not
have been found in the databases.  If a state relied
mostly on regulatory and land use databases, it
may have missed many smaller unregulated  PCSs
(such as residential septic tanks, underground stor-
age tanks, storm-sewer outfalls, pesticide mixing
areas, etc.) that could severely impact drinking-wa-
ter sources. Source Water Protection Partners now
have the opportunity to update and  enhance their
Examples of potential contaminant sources sometimes missed in
initial source water assessments.
Methods used by states to inventory PCSs in their
approved plan include, but are not limited to:
     Database searches of regulated facilities
      (those facilities with Clean Water Act dis-
      charge permits, with hazardous- or solid-
      waste permits, underground storage tanks,
      etc.) on state and federal databases.
     Additional/updated databases of PCSs avail-
      able from state and/or local health depart-
      ments and from environmental agencies.
     Land use maps of the delineated area (agri-
      cultural, high  intensity to low intensity resi-
      dential, industrial, etc.) usually created  at the
      state or local levels.
     Information from sanitary surveys and other
      local health- or environmental-agency data.
     On-site field inspections in the delineated
     Aerial photographs.
     Local tax and land-ownership  maps.
                 Complete inventories are important, because
                  unidentified potential contaminant sources
                     can endanger public water supplies.
                  Including one or more of these methods/tools
                  during assessment enhancement could be helpful
                  in states where these methods/tools had not been
                  used in the initial assessments.

                  States generally chose to perform either inventories
                  of contaminant sources, or inventories of specific
                  contaminants.  Examples of the former category
                  are gas stations, commercial  laundries, and photo
                  developers. In contrast, examples of the  latter
                  include Fecal Coliform, Triazine, and paint thinner.
                  The 1997 Guidance presents a "cross walk" listing
                  potential contaminants within specific PCS types.
                  Some state inventories were developed, at least
                  in part, by cross-referencing to either match facil-
                  ity/land use type with suites of contaminants, or the
                  specific contaminants were cross-referenced with
                  specific land uses/facilities. Where it is possible
                  to do so with reasonable resources, SWP Partners
                  might want to consider enhancing an assessment
                  by ground-truthing for the presence of the actual
                  contaminants  of concern at the inventoried  PCS
                  locations. Partners could prioritize ground-truthing
                  efforts by identifying those PCSs, such as railroad
                  yards,  most likely to have a very wide variety of
                  contaminants  not captured in the 1 997 Guidance's
                  cross walk.

                  Partner Actions to Update/Enhance
                  Contaminant Source Inventories
                  Source Water  Protection Partners may take any of a
                  variety of actions (some of which are listed below)
                  to enhance their CSI, if an enhanced or updated
                  inventory is considered to be  beneficial.

                  Partners may choose to undertake just one of these
                  activities, or conduct several at once or sequen-
                  tially overtime.  Most require little or no financial
                  resources, but all require an investment of time by
                  community employees or volunteers. These activi-
                  ties include:
How- To Manual: Update and Enhance Your Local Source Water Protection Assessments

  Encouraging broad participation of Partners
  in contaminant source inventories' updates/
  enhancements can lead to a wide range of
     people bringing the skills and energy
        needed to complete the effort.
Supplementing Initial Inventory with Local Data
     Convene a community meeting in the assess-
     ment area to obtain public input on PCSs.
     Conduct a more detailed inventory by walk-
     ing or driving through SWAs to locate addi-
     tional PCSs.
     Review the PWS's Consumer Confidence
     Look for other hidden routes of potential
     pollution reaching the drinking water supply
     (infiltration of urban runoff to ground water,
     unused  private wells or abandoned natural
     gas wells  providing a direct conduit to ground
     water, illegal hookups of sewer lines to storm
     drains, etc.).
     Identify wells under the influence of surface
     water that were not previously identified as
     Verify that the database information on  regu-
     lated facilities and land  uses is complete and
     Investigate local interest in obtaining the help
     of a source water or wellhead protection
     specialist from the state affiliate office of the
     National Rural Water Association to conduct
     a detailed inventory as part of a protection
     plan for the  community.
  Source Water Protection Partners convene community members
  to obtain public input.
     Work through sanitary survey technicians to
     have well/intake problems and additional
     PCSs identified (see Appendix B).
     Obtain information from relevant EPA reports
     and databases: (1) the National Water Qual-
     ity Inventory "305(b) report" (http://www.
     epa.gov/305b/2000report/ or contact the
     state agency; also see http://www.epa.gov/
     waters/305b/index.html); (2) the 303(d) list
     of impaired waters for the state (http://www.
     epa.gov/owow/tmdl/); (3) EnviroMapper
     (http://maps.epa.gov/enviromapper), which
     provides locations of, among other data
     elements, selected types of PCSs and their
     locations; (4) EPA's list of Potential Contami-
     nant Source Inventory Tools (http://www.epa.
     gov/safewater/mcl.html#mcls); and (5) EPA's
     list of watershed groups (http://www.epa.gov/
     adopt/network, htm I).
     Access the state geological survey website
     and the US Geological Survey website (http://
     www.usgs.gov) to determine if water-qual-
     ity data, documents and/or reports exist that
     include the SWA.
     Overlay locations of PCSs with ownership
     information to determine responsibility for
     on-site management.
     Contact facilities identified as PCSs to verify
     the CSI information.

Adding Information to Existing Data Sources and
Obtaining Additional Information From Data
     Add new types of data to existing data sourc-
     es to make these  sources more valuable for
     updating and  enhancing source water assess-
     ments.  For example, a tax map showing the
     presence of commercial establishments could
     be  enhanced to indicate parcels occupied by
     specific businesses,  and therefore, by implica-
     tion, PCSs, such as gas stations, dry cleaners,
     Local or state government employees who
     regularly visit sites located within SWAs could
     report new PCSs. (Some training likely would
     be  helpful, but this training  could be very
     basic.  In addition, new or increasingly lower-
     priced hand-held tools, for example, per-
     sonal data assistants and global  positioning
     systems, can expedite the process of precisely
     locating and reporting information about
     points of interest.)

 -" *FU-;    "          *:   V;'* >*^Ttf^*;. i***'*.
' *  '*./ '  '  '  "        * " - *\'j*" *   ; .    *' ' '"5^ -- *  
.-j.iwflr.i!"   .   - . * -j,  ^JiJto.<*T^k'   '"  *. ''    *.<     *-  *
Confirmation of the location of a septic system.

                                                         in place, etc., in order to determine if there
                                                         already are active pollution-prevention or
                                                         management efforts that could prevent the
                                                         release of PCS pollutants to the source water.
                                                         Review compliance records of identified PCSs.
                                                         Look at permit and monitoring data from
                                                         facilities that discharge wastewater to see the
                                                         types,  qualities and quantities of drinking-
                                                         water contaminants that are released to the
                                                         source water.
                                                         Obtain local other-than-PCS  information
                                                         (such as land-use descriptions, and state and
                                                         federal land management agency manage-
                                                         ment prescriptions).
Ascertaining That All Significant Potential
Contamination Sources are Identified and Located
     Verify that the locations of PCSs from the
     initial inventory are accurate.
     Map the locations of individual PCSs on local
     large-scale  maps to assist in prioritizing PCS
     impacts on the source water.
     Work with state and local agencies to ensure
     that PCS databases are updated to show im-
     proved or updated information (for example,
     add locally inventoried Class V wells to the
     state's Underground Injection  Control Class V

Evaluating Implementation and Effectiveness of
Existing Protection Strategies
     Perform interviews, owner surveys, tours of
     facilities, examinations of facility regulatory
     permits, expedited inspections, identifications
     and inventories of Best Management Practices

Performing Other Activities
     Update the initial inventory at regular inter-
     vals (every 3 or 5 years, etc.) to address new
     or discontinued land uses or activities.
     Determine if new PCSs added through local
     information-collection activities change the
     priorities identified in the initial assessment
     (see next section for information on updating
     the susceptibility determination).
     Check with state and federal agencies to
     determine if new data have, or access to
     existing data has, become available since the
     initial assessment was done.
     Inform and involve many local Partners to
     help in enhancing the initial assessment in a
     variety of ways.  All segments of the commu-
     nity should be involved in order to create an
     effective program.
     Review the following:  local and state land-
     use restrictions, comprehensive planning
     requirements,  and permitting requirements.
     Update them to include specific consider-
     ations of drinking-water quality impacts.
Encourag/ng Participation of Source Water
Protection Partners
Examples of local people and organizations that
can collect and compile information on past and
present PCSs include:
     Local public works or water system employees
     Local Board of Health, Planning Board or
     Conservation Commission members or staff
     Scout troops
     Retired  citizens and their organizations (for
     example, the Retired and Senior Volunteer
     Civic groups (Lions' Club, League of Women
     Voters, etc.)
     Neighborhood associations
     Environmental groups and watershed groups
     Building inspectors
     Local businesses and industry
     Other interested residents

A.  Critical Factors to Consider
    When Determining the
    Susceptibility of the Public
    Water Supply
 Source river to a public water supply.
   The susceptibility determination is the final
   result of a local source water assessment.
The susceptibility determination (SD) describes how
susceptible the public water supply PWS is (1) to
contamination from the identified potential contam-
inant sources (PCSs), or (2) to particular contami-
nants that could be released from those PCSs. The
1 997 Guidance recommended that states consider
and integrate four critical factors in their SD pro-
                    The presence of PCSs (from the inventory),
                    and the likelihood that contaminants will be
                    released from those contamination sources
                    (due to management practices and the nature
                    of the contaminant).
                    The physical integrity of the well or intake
                     (How likely is it that contaminants can enter
                     the drinking water system through physical
                     breaks or cracks in the well or the pipeline
                     connecting the well or intake to the public
                     water supply [PWS] facility?).
                    The sensitivity of the natural setting (the
                     degree and amount of protection afforded
                     by the natural hydrogeologic and hydrologic
                    The presence of existing or likely contamina-
                     tion in the source water.

                Presence of Potential Contaminant Sources
                and the Impacts of Contaminant
                Characteristics  and Management Practices
                The contaminant source inventory provides a list
                of PCSs within the source water area. Evaluation
                of the likelihood of contaminants from the PCSs
                reaching the source water will require that Source
                Water Protection  (SWP) Partners develop a process
                to periodically evaluate the likelihood that a con-
                taminant will escape from its containment.  The
                process can consist of maintaining and reviewing
                records from scheduled inspections; developing,
                distributing and possibly reviewing the responses
                to, a checklist mailed to PCS owners/operators;
                and/or employing any other vehicle that Partners
                view as protective.  The process should incorpo-
                rate obtaining information on the nature of the
                PCSs themselves, the  nature of the contaminants
How- To Manual: Update and Enhance Your Local Source Water Protection Assessments

contained within the PCSs, and the diligence and
training of the PCS owners/operators.

Physical Integrity
The large number of PWSs and the relatively short
time frame for submitting assessments led, for the
most part, to states making assumptions based on
age or similar factors related to the physical integ-
rity of wells, intakes and the conduits connecting
them to the PWS facility. An updating/enhance-
ment effort provides an opportunity for Partners
to take a closer look and reconsider the initial
assumption. Sanitary surveys provide a means of
evaluating the condition of a well and its likelihood
of being impacted by overland transport of con-
taminants.  Well integrity tests can be performed
but are  costly,  and may only be warranted if a PWS
owner/operator suspects a problem with the well
itself.  The concern over the physical integrity of an
intake is, more precisely, a concern regarding the
integrity of the entire pipeline from the source
water's  point of entry into the intake to  its point of
entry into the facility.

All above-ground portions of the intake/well-to-
pipeline-to-facility conduit may already be regularly
inspected.  However, the buried  portion is more
problematic and probably more costly to inspect.
Depending on the nature of the pipeline and the
flow within it, remote techniques may be available
to evaluate the integrity of the buried pipeline.  If
a PWS owner/operator has a reason to suspect
that breaches have occurred in the conduit (e.g.,
exposure to a natural or man-made event such as
an earthquake, landslide or explosion) the cost of
remotely inspecting the conduit is likely justified,
particularly if water-quality monitoring indicates a
post-event degradation in water quality.

Sensitivity of the Natural Setting
States addressed hydrogeologic sensitivity in their
initial assessment. However, natural and  human
forces can modify hydrogeologic sensitivity, al-
though  it is relatively stable.  For example, if the
confining layer that provides an aquifer with natu-
ral protection from pollutants has been compro-
mised by forces such as earthquakes or by human
activities such as well drilling or blasting for roads,
the sensitivity of the aquifer would have increased.

Source Water Protection Partners should also
consider if natural events such as earthquakes and
landslides may have altered not only the geologic
protection of an aquifer, but also the effectiveness
of vegetal cover and/or topographic features.

Presence of Natural Contamination in the
Source Wafer
Changes in the quality of source waters are gener-
ally related to the presence and management of
PCSs.  However, situations can occur where natu-
ral events lead to  changes in source-water qual-
ity.  The most obvious events are landslides and
flooding.  Catastrophic flooding of the Mississippi
River in the early 1 990s led to shallow floodplain-
aquifer contamination that likely lasted far beyond
the  period offloading. Chlorination and flushing
of wells would  only have resolved  the contamina-
tion problem for the area immediately around a
well and possibly  only temporarily. Fire damage
over extended  areas can also change source-water
quality, not just immediately from  burnt material
washing into surface water and from carbon leach-
ing  into the ground water, but also from the loss of
the  protection that is afforded by vegetation and by
the  development of  hydrophobic layers that cause
most rain events to run off rather than infiltrate.
  2001 Mississippi River flood: Locks and dam 5NM Northwest
  of Red Wing, MN almg the Mississippi River. Photo by NOAA.

B.  How States Combined These
    Factors to Arrive at a
    Susceptibility Determination

In general, the approach developed by each state
is fairly complicated; revising it may be beyond the
abilities of SWP partners, although revision is at the
discretion of the Partners.  Each state developed its
own system for combining information about (1)
the delineated area, (2) the  contaminant source
inventory, (3) PCS management and (4) the other
factors (for example, physical integrity of the well),
to determine the susceptibility of the raw-water
source. Many states used multiple steps or a matrix
to integrate the different factors to arrive at the final
SD. In states where Source Water and/or Wellhead
Protection are voluntary, it would  be a courtesy to
check with the state and provide the results of the
enhancement, if the state has the  capacity to use it.
States where Source Water and/or Wellhead Protec-
tion are required understate regulations generally
have requirements for periodic review and revision
of the protection plans. In these states, Partners
should ensure that their process meets state re-
quirements.  If the state's source water assessment
and protection methodology did not include all four
elements recommended for a determination, Part-
ners may want to consider revising the SD method
itself.  Similarly, PWSs/communities may take this
opportunity to include more physical or other fac-
tors in  their determinations.

C.  The Infra-system and
    Inter-system Approaches to
    Susceptibility Determination

The 1 997 Guidance presented two types of SDs, in-
tra-system and inter-system.  Most states performed
intra-system determinations, that  is, determinations
in which the PCSs within a particular source wa-
ter  area (SWA) were relatively ranked. Few states
performed an inter-system determination, which
would  have  identified the SWAs that were the most
susceptible to contamination by PCSs.

A state's intra-system approach might take these
four steps:
  (1) First, determine the source water's sensitivity
     based on natural aquifer or watershed char-
   EPA recommends enhancing assessments
   by including both infra- and inter-system
  (2) Then combine the sensitivity with information
     on the physical integrity of the well, intake,
     and/or conduit.
  (3) For each PCS, relate the information from
     steps 1  and 2 with information on the state-
     selected PCS characteristics of concern (e.g.,
     volume of discharge, toxicity,  etc.) for each
  (4) Use a consistent process to determine the
     final susceptibility of the PWS  to each PCS.

A state's inter-system approach might take these
five steps:
   (1) First, determine the source water's sensitiv-
      ity based on natural-aquifer or watershed
   (2) Then combine the sensitivity with  information
      on the physical integrity of the well, intake,
      and/or conduit.
   (3) Relate the information from steps 1  and 2
      with information on existing contamination
      in the source water and with  information on
      the numbers, locations, and characteristics
      (volume of discharge, toxicity of potential
      contaminants, presence of management
      measures, etc.) of the significant PCSs within
      the SWA.  Alternately, relate the above infor-
      mation to the specific contaminants within the
   (4) Use a consistent process to compute the final
      SD for the PWS.
   (5) Select and use a criterion to rank order the
      PWSs according  to their SDs.

Approved intra-system SD approaches produced at
least one of the following results:
     The susceptibility of the PWS to PCSs.
     The susceptibility of the PWS to contamina-
     tion by particular contaminants or classes of
     The overall (e.g., high/medium/low) suscepti-
     bility of a PWS to contamination.
Approved inter-system  determinations produce
some type of relative ranking of the susceptibility to
contamination of a PWS compared to the suscep-
tibility to contamination of other PWSs in the state.
EPA recommends enhancing SDs by including both
intra- and inter-system determinations.

  Intra-system determinations help the public
  water supply to prioritize potential contami-
  nant sources and the inter-system determi-
 nations help the state and sub-state areas to
        prioritize public water supplies.
D.  When and How Source Wafer
    Protection Partners Can
    Recalculate/Revise the
    Susceptibility Determination

Sometimes communities and other Partners have
information that was not readily available at the
time of the initial assessment. For instance, the
state's data may show that a water supply well was
constructed according to acceptable standards, but
the  community may have local data showing that
the  well's integrity is not good since contamination

Public water supply well.

leaks into the well from the ground surface dur-
ing heavy rains.  Such information could alter the
susceptibility result.

The introduction of new PCSs, along with changes
in the management of existing  PCSs, is likely to be
the most  common change in an assessment that
would prompt a revision of a SD. A new residen-
tial development, a permit for a feedlot or a mine,
the construction of a shopping  center with  a large
parking lot, the opening of a gas station or a dry
cleaner - all these are the types of activities that
may warrant a revision of the determination.  The
operating history and physical upgrades at a  local
factory could reduce the likelihood that the factory
would contaminate the water supply, and so may
also alter protection priorities identified in the as-
sessment. A decision by an owner/operator of one
or more PCSs to relocate outside the SWA, or out-
side a delineated critical area within the SWA, may
also be an occasion to revisit the determination in
order to decide if the threat to the drinking-water
supply  is thereby reduced and priorities should be

Aside from the relocation of PCSs within, or their
introduction into, a  SWA, changes in the manage-
ment of PCSs may call for taking another look at
the SD.  New regulations to ban or restrict cer-
tain land uses or operating  practices,  revisions in
zoning, the purchase and protection of land for
environmental purposes, a septic tank inspection
and maintenance program,  new Best  Management
Practices for  road or housing construction or storm-
water control, the adoption  of agricultural Best
Management Practices for nutrient management,
control of soil erosion, and  integrated pest man-
agement are just some of the measures that could
significantly change the results of the initial SD.

If an updated contaminant source inventory (CSI)
is performed and additional PCSs are identified,
cease or significantly modify operations, or their
management through protection measures is
significantly altered or a delineated boundary is
changed, then the SD will have to be  recalculated.
 Road expansion may add potential sources of contamination.

Similarly, if the delineation is enhanced or there is
additional information about SD factors, it is pos-
sible that the enhancement or new information will
lead to a different SD result or clarify protection
    Susceptibility determination results may
   change if (1) the susceptibility determina-
   tion value is recalculated using improved,
  updated and/or newly acquired information,
   (2) critical factors not included in the initial
   susceptibility determination are added to
  the susceptibility determination process, and
   change the process itself, or (3) an entirely
            new procedure is used,
            changing the process.
In some cases, a state may have identified a need
to revise its algorithm, or SWP Partners may choose
to add an enhancement to the state's SD method in
order to meet a specific need. For example, if Part-
ners are interested in land conservation, they might
choose to use as an enhancement, the method that
is described in Barten and Ernst's article, "Land
Conservation and Watershed Management for
Source Protection,"  in the April 2004 issue of the
Journal of the American Water Works Association
(pp.1 21-1 35). Barten and Ernst presented a proj-
ect approach with four interrelated components.
"First, a "fast track" approach was developed
to build on the results of [the] S[ource] W[ater]
Assessment] P[rogram]. ... Second, a Geographic
Information System (GIS) with  commonly available
data was used to develop conservation, restora-
tion, and stormwater management priority indexes
to clearly identify challenges, opportunities, and
critical information gaps; formulate a watershed-
scale strategy; ...The third component - a blend of
voluntary, place-based strategies for conservation,
restoration and stormwater management and regu-
lation - was designed to reduce current pollutant
loading from ... .  Finally,  a combined emphasis on
building consensus and political commitment and
requisite funding for land  conservation and pollu-
tion mitigation helped  ensure that early outcomes
and successes would foster sustained efforts to
protect source water."  (pp.1 23-4).


The 1997 Guidance presented several possible
vehicles for disseminating the results of the assess-
ments.  However, because of heightened security
concerns, many states changed their guidelines
and initial public information plans to restrict ac-
cess to data that could be seen as sensitive.

The Environmental  Protection Agency's (EPA's) Of-
fice of Water has developed a policy to manage
access to sensitive drinking-water-related informa-
tion that attempts to balance security concerns and
diverse state handling requirements with public
health goals, right-to-know requirements, and
other program and statutory responsibilities. The
Office of Water recognizes that wide dissemination
of information  is critical for promoting the local
actions required to  protect drinking water resources
and that increased  awareness, as in other security
efforts, can help increase security.
  At a minimum, when a public water supply
  receives the assessment that was completed
   as part of the state's EPA-approved  1453
   Source Water Assessment and Protection
   Program7, the public water supply system
    is required to provide information in the
  Consumer Confidence Report about (1) the
   availability of that assessment and  (2) a
  summary of the susceptibility of the system
               to contamination.
Appendix C provides contact information for read-
ers who are interested in the Source Water Protec-
tion assessment for their PWS.

Most states will provide specific wording as part
of the assessment report that can be used for this
purpose. (Asheville, NC is a good example:

Public water suppliers may provide additional
information in the Consumer Confidence Report.
This can include the results of efforts to update the
assessments or progress towards developing and
implementing a protection plan.  Here are two
good examples of such information:
    Ambient Water Quality Testing for
     Microbial Contaminants in  Corvallis, OR.
    Annual Household Waste Collection Event
     in Milford, Ml. (http://www.villageofmilford.

Other good opportunities for publicizing assess-
ment information are through PWS consumer
information websites such as the  Des Moines Water
Works website for watershed volunteer monitoring:
http://www.dmww. com/em pact_volunteer.asp.
2 States use different terms for EPA's Source Water Assessment and Protection Program, such as the Source Water Assessment Program, the
Source Water Protection Program and the Protection Program.

www.epa.gov/safewater                                                                                 21

After an assessment is completed and its results are disseminated, Partners can tackle the task of creating and
helping to implement a coordinated action plan for protecting their drinking-water supplies. In most cases, this
can be done in cooperation with other communities that share the same surface-water or ground-water re-
source.  Partners can also consider development of coordinated emergency responses to contamination inci-
Reservoir with sign urging protection of this drinking water source.
How- To Manual: Update and Enhance Your Local Source Water Protection Assessments

 (from least to
 most technically
Arbitrary Fixed
Fixed Radius
Variable Shapes
A circle with an arbitrarily
specified radial distance
from the well is drawn
around the well.
A circle is drawn around
a well at a distance that
is assumed to specify a
selected "time of travel",
which is the time that it takes
ground water or a ground-
water contaminant to reach
the well.
This method assigns
simple shapes to define
protection areas, based on
hydrogeologic and pumping
conditions at a particular
well. Method uses analytical
models and time-of-travel
considerations to determine
the shapes of the down-
gradient and up-gradient
protection areas, thus
generally creating source
water areas that are not
Source water areas are
delineated through the
use of equations to define
ground-water flow and/or
contaminant flow-and-
transport to the well.
Either an existing geologic
map is used or the area is
mapped by using geological
and/or geophysical data
and/or dye tracing methods.
Water levels in wells and
springs are measured;
dye-tracing may be used to
identify recharge areas for
wells in karst areas.
Computer models that solve
mathematical equations to
determine ground-water
flow and/or contaminant
flow and transport.
Easy, inexpensive.
Easy, inexpensive,
limited technical
expertise required.
Once background
information is
collected, requires
a small amount of
field data; limited
technical expertise
is required.
easily used by
require site-specific
Suitable in many
settings, but
particularly useful
in karst, and
Most accurate of
methods when
performed by a
High degree of uncer-
tainly, likely to overprotect
the well in one direction
and under-protect in the
opposite direction.
More accurate than
arbitrary fixed radius,
but has a high degree of
uncertainly and is likely
to overprotect the well in
one direction and under-
protect in the opposite
May not be accurate in
areas where geology
varies locally or where
ground-water flow
direction varies.
Costs vary depending
on amount of field data
Requires: high level
of professional
judgment, expertise
in geologic mapping
and/or geologic-map
interpretation, and
possibly skill in dye
tracing; may be costly.
High level of expertise
required; higher cost;
extensive field data
may be needed; limited
models available for
fractured-bedrock, or
karst, aquifers.
Often considered an initial
delineation approach.
Requires well pumping
rate and an estimate of the
aquifer porosity.
Uses analytical models and
time-of-travel considerations;
rarely used method.
Widely used method.
Hydrogeologically based
SWA boundaries are
generally practical only when
geologic maps already exist.
Particularly useful where
geology is complex and/or
a relatively high level of
accuracy is needed.

Note:  In the examples below, the states use the
term "Source Water Assessment program".

Sanitary surveys (Surveys) can be adapted to sup-
port source water assessments. Three short ex-
amples and one extended example are presented
below. These approaches could be utilized by
other states wanting to take advantage of the Sur-
vey process to enhance or update their Susceptibil-
ity Determinations (SDs).

Example 1:  State of New York

As part of their agreement with the state, coun-
ties in the state of New York will collect additional
information about their PWSs during Surveys and
site inspections and enter the data into an add-on
that the state developed for the SDWIS database.
The Basic Facility Data form was modified for use
with the Source Water Assessment Program to con-
tain state-specific  information: contaminant history,
locations of potential contaminant sources and well
logs.  These data were incorporated into assess-
ments as Discrete Contaminant Source Public Wa-
ter Supply Inventory and as  sensitivity drivers and
other information pertinent to overall susceptibility.

Example 2:  State of Louisiana

Sanitarians in the Louisiana Department of  Health
and Hospitals have conducted sanitary surveys
that have proven useful for updating Source Water
Assessment Program  data.  Health and Hospitals
has access to the Source Water Assessment Pro-
gram reports and checks them against the infor-
mation obtained during sanitary surveys. Health
and Hospitals notifies the Louisiana Department of
Environmental Quality if there are any errors in the
report, such as wells that are incorrectly numbered
or no longer active. Health and Hospitals also no-
tifies Environmental Quality if new wells have been
drilled, if a system has been closed, or if a new
system has come online; new systems are added to
the source water assessment database.

One Health and Hospitals staff person works with
Environmental Quality to  update the contaminant
source inventories. This staffer performs the field
work and then Environmental Quality updates
the database.  Currently, source water areas are
prioritized for updating based on well-update
information provided by the Health and Hospitals
sanitarians, or on a request from such individuals
and entities as the public, a government agency, or
a water system.  In the future, further prioritization
would be based on susceptibility to contamination
(as indicated by Source Water Assessment Program

Example 3: State of Michigan

The Source Water Assessment Score provides a
susceptibility determination for Michigan's non-
community wells. One element of the Score is non-
community PWS-well construction, maintenance,
and use, which are determined as part of the
sanitary-survey process. States, the PWS, or Source
Water Protection  Partners could take advantage  of
this scoring system to re-evaluate well integrity as
information becomes available during the sanitary-
survey cycle.

Example 4: State of Nebraska

The description below consists of selected text from
Nebraska's Source Water Assessment Program,
Chapter V: Source Water Assessment Program
Vulnerability Analysis (http://www.ndeq.state.ne.us/
click on Water Division, scroll down and click on
SWA Program).

5.1 Vulnerability Definition

For purposes of Nebraska's Source Water Assessment Program, the terms susceptibility and "vulnerability" are
interchangeable. Nebraska has chosen to use the word vulnerability.  Both the Safe Drinking Water Act Amend-
ments and EPA's Source Water Assessment and Protection Programs Guidance encourage the use of existing
information and coordination with other programs. Using the existing Survey for the first phase of the vulner-
ability analysis is a use of effective information and cooperation between programs. The following chart shows
examples of the information examined and recorded when a Survey is completed by Nebraska Health and Hu-
man Services (Health Department).
Sanitary Survey Inspection Categories Examples
Well House Mechanical
Auxiliary Equipment
Storage Tanks
Truck Fill Location
Distribution System
Operating Practices
Treatment Plant
Water - Quality, Quantity, Use, Lab Reports
Site - Access, Drainage, Encroachment
Base - Seal, Motor Mount, Bolts
Piping - Supports, Ties, Sleeves, Corrosion
Chemical - Safety, Storage, Controls, Pump
Condition - Structural, Corrosion, Leaks
Backflow Prevention - Vacuum Breaker
Material Storage and Spare Parts
New Construction and Abandonment
Wellhead Encroachment Policy, Emergency Plan
Sites, Structures, Buildings and Bins, Waste Handling
A Public Water Supply System's (PWSS's) vulnerability to contamination is based on several factors:
     Integrity of the well (ground water) or intake (surface water) construction.
     Geologic environment, including depth to water, presence of retarding sediments in the subsurface
      (ground water).
     Nature of the surface water source and watershed-large lake, small stream, large river, etc.
     Locations of potential contaminant sources in the Wellhead Protection Area or watershed delineation area.

Nebraska is proposing a two phase Vulnerability Assessment, much like the two level Contaminant Source
Inventory (CSI). The database search that was done as the level one CSI will be provided to Health Department
field representatives to aid them in completing a Survey for a PWSS. The existing Survey vulnerability determina-
tion will be used for the first phase, and a  more detailed vulnerability analysis of the PWSS will be done using
the information from the "on-the-ground" inventory of potential contaminant sources ... and specific site infor-
mation. This second vulnerability will be called a "Contamination Potential Rating".

The first phase vulnerability analysis will assist PWSSs in focusing their local voluntary protection activities on the
wells and  locations that are more vulnerable to contamination. As Contamination Potential Ratings are complet-
ed, PWSSs will also benefit from this advanced analysis when assessing resources and protection activities for
the Assessment Area (24 hour Time of Travel) in the watershed or the Wellhead Protection Area. It is also pos-
sible that results of the second phase vulnerability will be coordinated in the future to the Drinking Water State
Revolving  Loan Fund ... priority list.

                         This page represents selected text from Nebraska's Source Water Assessment Program

5.2 Ground Water Systems

5.2.1 Phase One - Existing Sanitary Survey Program

The Health Department visits all PWSSs to conduct a  Survey. The phase one vulnerability analysis for the Source
Water Assessment will not change from the existing Health Department Survey rating. Community PWSSs are vis-
ited once every 3 years and Non-Community PWSS are visited once every 5 years. The Survey is a vulnerability
assessment done within 1 000 feet of a well. A well is given a  rating of vulnerable or not vulnerable to contami-
nation. Specific components of a PWSS are evaluated in a Survey, including source water, treatment, storage, the
distribution system, and maintenance.

The phase one vulnerability analysis 1 000 feet review distance is not inclusive of the entire source of drinking
water for the PWSS. However, it has been determined that for a "middle" sized PWSS well, 1 000 feet is inclusive
of the 2 year Time of Travel (TOT) zone within the Wellhead Protection  Area. This 1 000 foot radius may include
as much as the 5 year TOT (this 5 year TOT is  not routinely calculated  for the Wellhead  Protection Program). This
zone is the most crucial area to protect and  the Health Department's regulations reflect this need.

The Nebraska Department of Environmental Quality (Environment Department) intends to use all existing Survey
data with cooperation from the  Health Department to make a "first round" vulnerability analysis. This first phase
vulnerability analysis will  be accessed in the Health Department's files  for the initial  Source Water Assessment
given to the  PWS. ... It should be noted that no changes will be  made to this already existing Survey program
and vulnerability assessment.  PWSSs may challenge the "vulnerable" or "not vulnerable" rating given  to them by
the Health Department's  ... Being rated "vulnerable" usually means the  PWSS may not be eligible for  additional
monitoring waivers.

5.2.2 Phase Two - More Detailed Vulnerability Analysis

A more detailed vulnerability analysis will be made by the Environment Department after the results of the vol-
untary "on-the-ground" CSI by the  PWSS (or individuals, agencies, or organizations helping with inventories) are
given to the  Environment  Department.  A review of available PWS well  information from the Wellhead  Protection
Program file and EPA's database, SDWIS, of PWS information and violations, will be undertaken and a table
completed (see Table 5.2). A Vulnerability Score will be the result of filling out the table. The scores will fall into
different ranges, high to low, that will compare vulnerability of PWSSs  across the state (see Table 5.1). It should
be noted that vulnerability scores will be ranked differently for Community ground water systems, Non-Commu-
nity ground water systems, and surface water systems. This means a score of 40 does not mean the same thing
for the above noted categories (see Table 5.7). The second phase vulnerability determination  is independent
of the initial  rating by the Health Department's Survey. This second phase vulnerability determination will help
PWSSs prioritize and plan local  protection activities.

Table 5.1 Vulnerability Scores Ranking  for Ground Water Community PWSSs
                                                    < 45
It is likely that more information about the well(s) and local geology will be needed after an initial review of the
Wellhead Protection Program file is completed. The Environment Department will work with the local PWS opera-
tor, the Health Department's field representative and any other organizations which may have more site specific
information available (Nebraska Rural Water Association, Natural Resources Districts, University Nebraska Lin-
coln-Conservation and Survey Division, local County Health Departments, etc.). The Environment Department
may contract with consultants, agencies, or organizations to complete this task. A PWSS may hire a consultant or
engineer to complete this task, as an addition to a local Wellhead Protection Program. Vulnerability Analyses

                         This page represents selected text from Nebraska's Source Water Assessment Program

26                                                     i    ,                       ,

done by consultants and engineers on behalf of the PWS will be reviewed by the Environment Department for
completeness and adequacy prior to acceptance. By the Environment Department performing or reviewing all of
the Contamination Potential Ratings, statewide consistency will be maintained.

Table 5.2 - Second Phase Vulnerability Analysis for Ground Water Community PWS wells - ranking by well or by
well field, only if wells are in close proximity and share similar characteristics.
Characteristic Point System
Depth to water
Vadose (unsaturated) zone (zone above
water table)
Age of well
Potential Contaminant source within
Wellhead Protection Area1 - includes
potential nonpoint2 sources
Transportation corridors within Wellhead
Protection Area
Average PWSS nitrate as nitrogen
concentration over last 5 years
Detection of any contaminant regulated
under drinking water quality standards
in last 5 years (not including Coliform)
Existing land use or zoning ordinances
for water quality concerns or protecting
Natural Resources District Ground Water
Management Area in place
< 1 0 feet
1 0 - 50 feet
> 50 feet
All sand and/or gravel
1-15 feet of clay present
> 1 5 feet of clay present
Constructed before 5/77
Constructed after 5/77 , but before 5/86
Constructed (or reconstructed) after 5/86
Inside 2 year TOT
Within 2 year to 1 0 year TOT
Outside 1 0 year TOT
Mainline railroad or pipeline
Major highway or interstate intersection
State or federal highway or interstate
County roads or city/village streets
Below or equal to 5 parts/million (ppm)
Between 5-7 ppm
Between 7-10 ppm
At 1 0 ppm or above
Any at or below 50% max contaminant
level (MCL)
Any above 50% MCL, but < MCL
Any at or above MCL or Administrative Order
Local Wellhead Protection Program
Phase 1
Phase II higher
Choose one
Choose one
Choose one
Choose highest value
Choose highest value
Choose one
Choose one
Choose one
Choose one
1. Potential contaminant sources from "on-the-ground" inventory and from the Environment Department's database search.
2. Nonpoint sources are usually associated with agricultural production where fertilizers and pesticides are applied. Pasture or wooded
   land is not usually included as potential nonpoint sources of contamination.
                           This page represents selected text from Nebraska's Source Water Assessment Program

5.2.4 Non-Community PWSS

For Non-Community PWSS (both transient and non-transient), the same phased approach to vulnerability as-
sessments will be taken as for Community PWSS, but on a less detailed scale. The first phase will be simply the
Health Department's "vulnerable" or "not vulnerable" rating, based on the results of the Survey (done once
every 5 years for Non-Community PWSSs).

For the second phase, an area-wide approach will be used. All non-community PWSSs in a county will  be plot-
ted on a  county, Natural  Resources  District, or some regional  map. Ground water nitrate concentrations for the
county (or Natural Resources District) from the University of Nebraska - Water Center Clearinghouse project
(soon to  be accessible on the Nebraska Natural Resources Commission internet web site) will be plotted or as-
sessed within a one mile  radius of the PWS well(s). Regional nitrate concentrations,  PWSS monitoring violations,
and regional depth to water will be  taken into account for this Contamination Potential Rating.

Table 5.3 Second Phase Vulnerability Analysis for Non-Community PWSS
 Monitoring detections of
 regulated contaminant not
 meeting drinking water
 quality standards in last 5
 years (including coliform)
 Regional nitrate
 Regional depth to water
Point System
Average < 7 ppm in 1 mile radius
Average > 7 ppm in 1 mile radius
< 50 feet
> 50 feet
Table 5.4 Vulnerability Scores Ranking for Non-Community PWSS
 High Vulnerability
Medium Vulnerability
Low Vulnerability
                                   0- 10
As more information about these types of vulnerability assessments become available, the Environment Depart-
ment will consider refining this process. If deemed necessary, the Environment Department will submit a Source
Water Assessment Program amendment to EPA.

5.2.5 Vulnerability by Well, Wellfield, or by System

Currently, the Health Department determines vulnerability for individual wells, unless several wells use a com-
mon Point of Entry. This same rating by well or Point of Entry will be used for the first phase of vulnerability analy-
sis in the Source Water Assessment Program.

For the second  phase of the vulnerability analysis, the Environment Department will look at wells in the same
contiguous Wellhead  Protection Area for a common vulnerability rating. Often PWSSs will have more than one
wellfield, separated by more than a mile. Each separate Wellhead Protection Area will be rated using the appro-
priate table from this section. This second phase rating does not change the rating given by the Health Depart-
ment in the Survey process; it is intended to be used for planning purposes.
                         This page represents selected text from Nebraska's Source Water Assessment Program

5.3 Surface Water Systems

Surface water systems undergo the same Survey with the Health Department as the ground water PWSSs. The
same two-phased approach will be used for these systems, as explained above. The following table (Table 5.5)
reflects modifications needed for the surface water systems.

Table 5.5 Second Phase Vulnerability Analysis for Surface Water Systems
Characteristic Point System
Integrity of intake, from last Health
Department inspection
Size of Watershed Delineation Area
Potential contaminant source
within Assessment Area2 - includes
potential nonpoint3 sources and
permitted discharges
Transportation corridors within
Assessment Area (24 hour TOT)
Detection of any contaminant
regulated under drinking water
quality standards in last 5 years (not
including coliform)
Existing land use or zoning
ordinances for water quality
> 35 square miles
< 35 square miles
Main line railroad or
Major highway or interstate
State or federal highway or
County roads or city/village
Any at or below 50% MCL
Any above 50% MCL, but
less than MCL
Any at or above MCL or
Administrative Order
Local Watershed Protection
Program or project4
Choose one
Choose one
Choose one
Choose highest value
Choose highest value
Choose highest value
2. Potential contaminant sources from "on-the-ground" inventory
3. Nonpoint sources are usually associated with agricultural production where fertilizers and pesticides are applied. Pasture or wooded
  land are not usually included as potential nonpoint sources of contamination.
4. Local Watershed Protection program or project could be a CWA319 project, Nebraska Environmental
  Trust project, or other local/state program to protect the watershed and/or educate the public.
                           This page represents selected text from Nebraska's Source Water Assessment Program

Table 5.6 Vulnerability Scores Ranking for Surface Water Community PWSS
 High Vulnerability      Medium Vulnerability  Low Vulnerability
5.3.1 Explanation of Table Characteristics

Many of the Vulnerability Analysis characteristics are the same between ground water and surface water systems.
Please see section 5.2.3 for these common explanations.

Table 5.7 Summary of Different Types of PWSSs Vulnerability Scores
Type of PWSS High Vulnerability Medium Vulnerability Low Vulnerability
Community, Ground Water
Non-Community, Ground Water
Surface Water
> 65
> 20
> 40
45 -65
0- 10
< 20
Integrity of Intake, from Last Health Department Inspection
The health Department routinely inspects surface water intakes as part of their Survey program and ongoing
work with PWSSs. Integrity of an intake structure for a surface water system should include:
     Withdrawal of water from more than one level if quality varies with depth (most often in a lake, but if the
     potential exists for a chemical spill  it may also apply to a river).
     Should be a valve at each inlet and also a valve in the pipeline in case inlet valves are damaged/malfunc-
     Adequate protection against damage by ice, anchors, etc.
Integrity and safety of the intake to accident are evaluated in this inspection and  reflect on the vulnerability of the
system to contamination.

Size of Watershed Delineation Area
A PWSS in a larger watershed delineation area will be more vulnerable to contamination than a smaller one due
to a greater number of potential  sources.

Existing Land Use or Zoning Ordinances for Water Quality Concerns
Counties may have controls (zoning, ordinances, etc.) that are protective of water quality. Local sponsors (such
as Natural Resources Districts,  City of Omaha,  etc.) have implemented watershed or lake projects that put Best
Management Practices on the land and help educate land owners about surface  water quality.  Points are given
for these types of projects that could lower a  PWSS's vulnerability.

5.4 Responsibility

The Environment Department will assume the responsibility of  compiling the data from the Survey Program with
assistance from the Health Department, for the first phase of the vulnerability assessment/analysis. After the
results  of the voluntary "on-the-ground"  inventory  are given to the Environment Department, it will also under-
take the Contamination Potential Ratings for a PWSS. In addition, the state or its contractors/cooperotors will do
a Contamination Potential Rating (including a second round CSI  within 3 hour TOT)  for all surface water systems
in Nebraska by May 2003. The goal for the Contamination Potential Ratings is to complete 90% of the PWSSs by
the year  201 0. A new Source Water Assessment, reflecting the Contamination Potential Rating, will be sent to the
PWSS.  An explanation of  how the new vulnerability score was determined will be  provided. The PWSS owner will
be required to make this Assessment known and available to the public.

                         This page represents selected text from Nebraska's Source Water Assessment Program

                                                      ,     ..
                                           ^	; i:--:..v/-. L, ;J

(Note:  in many states where the water supplier is listed as the contact, the supplier has the option of providing
access to the assessments on a case-by-case basis.)
Alabama: contact the water supplier.

Alaska: contact the water supplier or Alaska
Resources Library and Information Services

Arizona: contact Donna Lucchese (602-771-
4641), Arizona Department of Environmental
Quality, Source Water Assessment and Protection

Arkansas: http://www.healthyarkansas.com/eng/
swp/swapinfo.htm (see pull-down menu; scroll
down to and click on, eng-public water system
information; navigate to water system of interest;
clearly state that  you would like a source water pro-
tection assessment report); alternately contact  Lyle
Godfrey (501 -661 -2623), Arkansas Department of

California: http://swap.ice.ucdavis.edu/TSinfo/

Colorado:  http://www.cdphe.state.co.us/wq/sw/
SWAP/swa preports. htm I

Connecticut:  http://www.dph.state.ct.us/BRS/

Delaware:  http://www.wr.udel.edu/swaphome/

District of Columbia:  http://www.potomacriver.
org/water_qua I ity/swa preport.htm

Florida:  http://www.dep.state.fl.us/swapp/

Georgia:  available for review at the Georgia
Environmental Protection Division office in Atlanta
(contact: Sue Grunwald, 404-656-071 9), or at the
water supplier.

Hawaii: contact  the water supplier.

Idaho:  http://www.deq.state.id.us/water/
Illinois:  http://www.epa.state.il.us/water/

Indiana:  contact the water supplier for community-
system assessments; for non-community assess-
ments contact James Sullivan (31 7-308-3388),
Indiana Department of Environmental Manage-

Iowa: contact Michael Anderson (515-725-0336),
Iowa Department of Natural Resources; assess-
ments are available on a case-by-case basis.

Kansas:  http://www.kdheks.gov/nps/swap/

Kentucky: contact Bill Caldwell (502-564-3410),
Natural Resources and Environmental Protection
Cabinet, Watershed Management Branch.

Louisiana: contact the water supplier.

Maine:  contact Robin Frost (207-287-2070),
Division of Environmental Health, Drinking Water

Maryland: contact the central  library of the county,
the County Environmental Health Director, the wa-
ter supplier, the County Public Works  or the Public
Planning and Zoning departments.

Massachusetts:  http://www.mass.gov/dep/water/
drinking/swap, htm

Michigan: contact Elgar Brown RE. (51 7-241 -
1359), Department of Environmental Quality.


Mississippi: http://deq.state.ms.us/MDEQ.nsf/

Missouri:  http://drinkingwater.missouri.edu (Note:
An ID must be obtained to use this website. IDs
are available from the water system or from the
Missouri Department of Natural Resources, Public
Drinking Water  Branch [573-751-5331]).

Montana: http://nris.state.mt.us/wis/swap/

Nebraska:  contact Deana Barker (402-471-6988),
Nebraska Department of Environmental Quality,
Water Quality Division.

Nevada: contact Jim Balderson (775-687-9517),
Nevada Division of Environmental Protection.

New Hampshire:  http://www.des.state.nh.us/
dwspp/reports, htm

New Jersey: http://www.state.nj.us/dep/swap/

New Mexico:  contact Darren Padilla (505-476-
8631), New Mexico Environment Department.

New York:  contact the County Health Department
or the water supplier.

North Carolina: http://www.deh.enr.state.nc.us/
pws/swap, click on Learn About Your Drinking Wa-
ter Source (Computer Application).

North Dakota: contact Jim Horner (701 - 328-
521 6), North  Dakota Department of Health.

Ohio:  contact the Ohio Environmental Protection
Agency, Division of Drinking and Ground Waters
(614-644-2752) or the water supplier.

Oklahoma: contact the Oklahoma Department of
Environmental Quality, Environmental Compliance
and Local Services Division (405-702-6100) for
further information.

Oregon: http://www.deq.state.or.us/wq/dwp/

has summaries only; for a full assessment report
contact the  water supplier or the regional office
of the Pennsylvania Department of Environmental

Puerto Rico: http://prdata.er.usgs.gov/swap/, click
on Search PWS database.

Rhode Island: http://www.health.ri.gov/
South Carolina: http://www.scdhec.net/water/

South Dakota: contact the water supplier; with the
supplier's concurrence the state will provide the

Tennessee:  summaries can be found  at:
http://gwidc.memphis.edu/website/dws/risk/ ; see
also http://www.state.tn.us/environment/dws/
dwassess.shtml; for further information, contact
Thomas A. Moss, (615-532-01 70), Tennessee
Department of Environment and Conservation,
Division of Water Supply.

Texas:  contact the water supplier.

Utah: contact the water supplier.

Vermont: assessments may be viewed at the water
system; they may also be viewed or obtained  from
the Vermont Department of Environmental Conser-
vation, Water Supply Division (802-241 -3400).

Virginia:  contact Virginia Department of Health,
Office of Water (804-864-7500) for field-office
phone numbers.

Washington:  contact David Jennings  (360-236-
3149), Washington State Department of Health,
Information Management Section.

West Virginia:  contact Scott Rodeheaver (304-558-
671 3), West Virginia Department of Health.

Wisconsin:  contact the water supplier.

Wyoming: contact Kim Parker (307-777-6128),
Wyoming Department of Environmental Quality.


Source Water Protection Partners may find reading the following assessments particularly helpful when
considering updates and enhancements (this is not an exhaustive list):

       Assessments posted on the Montana website
       New Jersey

CSI:    Contaminant Source Inventory

EPA:    Environmental Protection Agency (United States EPA, unless stated otherwise)

MCL:  Maximum Contaminant Limit

PCS:   Potential Contaminant Source

ppm:  parts per million

PWS:  Public Water Supply (depending on context, may also mean public water supply system)

PWSS:  Public Water Supply System

SD:    Susceptibility Determination

SWA:  Source Water Area (in some states, this area may be called the Source Water Protection Area,
       the 1 453 Area, or the Protection Area)

SWP:  Source Water Protection

TOT:   Time of Travel

LJSDA:  U.S. Department of Agriculture

Office of Water
September 2006