&EPA
Small Drinking Water Systems
Handbook

A Guide to "Packaged"
Filtration and Disinfection
Technologies
with
Remote Monitoring and
Control Tools
          A "Packaged" Solution For A Site In Rural West Virginia

          Filtration (Before)
          Ultrafiltration System
             (After)
                             Remote Monitoring
                               and Control

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                     DISCLAIMER

The information presented in this document relates to research
on small drinking water systems conducted by the Water Sup-
ply and Water Resources Division (WSWRD) of the United
States Environmental Protection Agency (EPA).  The
WSWRD is a  division of the National Risk Management
Research Laboratory, Office of Research & Development.

This research was performed at the EPA's Test & Evaluation
Facility in Cincinnati, Ohio, and at other field locations.  It
has been subjected to the EPA's peer and administrative re-
view.  Mention of trade names or commercial products in this
document does not constitute an endorsement or recommen-
dation for use.

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                                    EPA/600/R-03/041
                                        May 2003
   Small  Drinking Water Systems
               Handbook
 A Guide  to "Packaged" Filtration and
Disinfection Technologies with Remote
     Monitoring and Control Tools
            U.S. Environmental Protection Agency
            Office of Research and Development
          National Risk M anagem ent Rese arch Lab oratory
           Water Supply and Water Resources Division

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                                             Small Drinking Water Systems Handbook




Contents
                                                                     Page




    List of Tables  	ii




    List of Figures 	 iii




    Acronyms and Abbreviations	 iv




    1.0    Introduction 	1




    2.0    Contaminants in Drinking Water 	3




    3.0    Common Water Supply Problems and Recommended Solutions	5




    4.0    Reg u I atory Ove rvi ew	9




    5.0    Common Violations 	13




    6.0    Treatment Technologies	15




    7.0    Point-of-Use/Point-of-Entry Applications	35




    8.0    Remote Monitoring/Control 	41




    9.0    A Real World Packaged Solution	45




    10.0   Funding and Technical Resources	49




    11.0   Additional Information Sources	55




    12.0   References	63

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Small Drinking Water Systems Handbook
List of Tables
Table 3-1
Table 3-2
Table 4-1
Table 4-2
Table 4-3
Table 4-4
Table 4-5
Table 5-1
Table 5-2
Table 6-1
Table 6-2
Table 6-3
Table 6-4
Table 6-5
Table 6-6
Table 6-7
Table 6-8
Table 6-9
Table 6-10
Table 7-1
Table 7-2
Table 8-1
Table 8-2
Table 9-1
Table 10-1
Table 10-2
Table 10-3
Troubleshooting/Testing for Common Water Supply Problems
Emergency Disinfection Treatment for Drinking Water
Size Categories of Public Water Systems
Distribution of Water Systems
National Level Affordability Criteria
General Sample Monitoring Schedule for Small Systems
Small System Regulatory Summary
Total Coliform Bacteria Violations for the Period October 1, 1992 through
December 31, 1994
Chemical Contamination Violations for the Period October 1, 1992
Through December 31, 1994
Surface Water Treatment Compliance Technology
Regulated Contaminant List (partial) and Possible Removal Technologies
Bag Filter Characteristics
Bag Filtration Performance Summary
Cartridge Filter Characteristics
Cartridge Filtration Performance Summary
Membrane Filtration Performance Summary
Filtration Summary Table
Summary of Disinfectant Characteristics Relating to Biocidal Efficiency 	
Disinfection Summary Table
Key Feature Summary of Commonly used POU/POE Technologies
Summary of Treatment Technologies and Costs
Amenability of RTS to Treatment Technologies Used for Small Water
Systems
Cost Estimates of SCADA System Components
Raw Water Quality and Contaminant Specifications
Federal Funding Programs for Small Public Water Systems
Technical and Administrative Support for Small Public Water Systems 	
Foundation Backing Rural Economic Development Program
Page
5
6
10
10
11
11
12
13
13
16
17
20
22
24
25
25
26
29
33
37
38
42
42
45
52
52
53

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                                      Small Drinking Water Systems Handbook




List of Figures
Figure 1-1
Figure 3-1
Figure 6-1
Figure 6-2
Figure 6-3
Figure 6-4
Figure 6-5
Figure 6-6
Figure 6-7
Figure 6-8
Figure 6-9
Figure 6-10
Figure 6-11
Figure 6-12
Figure 6-13
Figure 6-14
Figure 6-15
Figure 6-16
Figure 6-17
Figure 6-18
Figure 6-19
Figure 6-20
Figure 6-21 a
Figure 6-21 b
Figure 6-22
Figure 6-23
Figure 6-24
Figure 6-25
Figure 6-26
Figure 6-27
Figure 7-1
Figure 7-2
Figure 8-1
Figure 9-1
Figure 9-2
Figure 9-3
Figure 9-4
Figure 9-5
Figure 9-6
EPA Test & Evaluation Facility, Cincinnati, OH
Canteen and Tablets for Emergency Purification Using Iodine
Particle Size Distribution of Common Contaminants and Associated
Filtration Technology
Clogged Prefilter
Typical Bag Filter
Cut-Away of Bag Filter
Bag Filter Showing Rip in Seam
Bag Filter Showing Bag Rupture
Bag Filters Showing Discoloration Associated with Bypass
Bag Filters Showing Discoloration Associated with Bypass
Different Configurations of Bag Filters Tested
Influent vs Effluent Particle Counts
New Bag
Dirty Bag
Cartridge Filters and Housings
Dirty and Clean Cartridge Filters
Normal Cartridge Filter
Collapsed Cartridge Filter
UF System
Cracked Plastic Adaptor Used Between Membranes
Log Removal of Beads vs. Membrane Run-Time
Number of Beads in Effluent vs. Run Time
Cryptosporidium Oocyst on Upper Surface of 3 Micron Pore
Cryptosporidium Oocyst Coming through 3 Micron Pore
Micro Filtration System
On-Site Chlorine Generator #1
On-Site Chlorine Generator #2
On-Site Chlorine Generator #3
Package AOP Plant MTBE Removal vs Time, 30 ug/L Batch Test Run 	
Package AOP Plant Formation of t-BF vs Time Injecting 30 ug/L MTBE _
Typical RO Unit under a Kitchen Sink
AOP POE Unit Installed in a Cellar
Possible Layout(s) of a Remote Telemetry System
McDowell County
Old Treatment System
Packaged UF System
New Cinder Block Building
Welcome Screen
System Summary
Page
1
7
18
19
20
21
21
21
21
21
21
22
22
23
23
24
24
24
26
26
27
27
27
27
27
32
32
32
34
34
36
40
43
45
45
46
46
47
47

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      Small Drinking Water Systems Handbook
     Acronyms  and Abbreviations

     AOP      advanced oxidation process           nm
     ARC      Appalachian Regional Commission    NPDWR
     BAT      best available technology
     bdl       below detection limit                 NTNCWS
     CCL      Contaminant Candidate List
     cfu       colony-forming unit                  NTU
     cm2      square centimeter                    O&M
     CT       contact time                        O3
     CTA      cellulose triacetate                   PCE
     CWS      community water systems             PAH
     DC       direct current                       PDCO
     D/DBP   disinfectants/disinfection by-products   PLC
     DWS     drinking water systems               POE
     DWSRF  Drinking Water State Revolving Fund   POU
     EPA      United States Environmental           ppb
               Protection Agency                   psi
     ESWTR  Enhanced Surface Water Treatment    PVC
               Rule                               PWS
     ETV      Environmental Technology Verification   REA
     GAC      granular activated carbon             RO
     gpd      gallons per day                     RTS
     gpm      gallons per minute                   RUS
     HAA     haloacetic  acid                      SCADA
     HFTF     high-flow,  thin film
     hh       household                          SOC
     HPC      heterotrophic plate count              SDWA
     HUD     Housing and Urban Development      SDWR
     IHS      Indian Health Service                SMCL
     IRS       Internal Revenue Service              SWTR
     MCL      maximum  contaminant level           T&E
     MCLG   maximum  contaminant level goal      TEA
     ME       microfiltration                       TFB
     MHI      median household income            TCDD
     |ig/L      micrograms per liter                  TCE
     MCPSD  McDowell County Public Services      TDS
               Division                            THM
     mg/L     milligrams per liter                   TNCWS
     mL       milliliter                            TOC
     mm      millimeter                          TT
     M/R      monitoring/reporting                 UF
     MTBE    methyl-tert-butyl-ether               UV
     MWCO   molecular weight cut-off              UV/O3
     mWsec   milliwatt second                     VOC
     NCWS   non-community water system          WSWRD
     nd       not detected
     NF       nanofiltration
nanometer
National Primary Drinking Water
Regulations
non-transient non-community water
system
nephelometric turbidity unit
operation and maintenance
ozone or ozonation
perchloroethylene
polynuclear aromatic hydrocarbon
pore diameter cut off
programmable logic controller
point of entry
point of use
parts per billion
pounds per square  inch
polyvinyl chloride
public water  system
Rural Electrification Administration
reverse osmosis
remote telemetry systems
Rural Utilities Service
Supervisory Control and Data
Acquisition
synthetic organic compound
Safe Drinking Water Act
Secondary Drinking Water Regulations
secondary maximum contaminant level
Surface Water Treatment Rule
Test and Evaluation
?-butyl  alcohol
£-butyl  formate
tetrachlorodibenzo-p-dioxin
trichloroethylene
total dissolved solids
trihalomethane
Transient non-community water system
total organic  carbon
treatment technology
ultrafiltration
ultraviolet
ultraviolet/ozone or ozonation
volatile organic compound
Water Supply and Water Resources
Division
IV

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    1.0  Introduction
                                                              Small Drinking Water Systems Handbook
    Those of you who live in small communities, enjoy
    camping, eating in restaurants, or work at a location
    that provides its own drinking water, are entitled to
    the safest and most economical supply of water. The
    federal government recognizes that safe and afford-
    able drinking water is something that all are entitled
    to and not just those who live in "big" cities. How-
    ever, with this recognition comes responsibility.
    Current and future drinking water regulations apply
    to all drinking water systems that serve at least 25
    consumers or 15 connections for at least 60 days per
    year. These  federal and state regulations are designed
    and implemented to manage, protect and enhance the
    quality of drinking water provided to all consumers.
To Find Reports on Several Small System Issues:
 www.epa.gov/safewater/smallsys/ssinfo.html
    These regulatory requirements pose a "serious"
    challenge to the small, public water system (PWS)
    operators (serving fewer than 10,000 people) that
    often do not have the technical, managerial, or
    financial resources to adequately meet these require-
    ments. Also, there are several different approaches to
    treating, distributing, and maintaining drinking water
    quality to meet the same regulatory requirements.
    Selecting an appropriate approach requires a basic
    knowledge and understanding of types of contamina-
    tion, available treatment technologies, distribution
    system fundamentals, and applicable regulations.
    Appropriate technology should be selected based
    upon an understanding of these elements combined
    with site-specific criteria, such as source water
    location, availability of funding, vendor support, and
    ease-of-operation.
    Considerable information about small drinking
    water systems is already available, much of it
    from the United States Environmental Protec-
    tion Agency (EPA). The intent of this
    handbook is to highlight information
    appropriate to small systems with an empha-
    sis on filtration and disinfection technologies
    and how they can be "packaged" with remote
    monitoring  and control technologies to providi
    a healthy and affordable solution for small
    systems. EPA evaluated several commercially
    available pre-fabricated "package plants"
    suitable for small systems. This document
    provides a background on regulations perti-
    nent to small systems and presents a sum-
    mary of related research conducted by EPA's
    Water Supply and Water Resources Division
    (WSWRD)  at the EPA Test & Evaluation
         (T&E) Facility (Figure 1-1) in Cincinnati, Ohio, and
         at other field locations. The WSWRD is a division of
         the National Risk Management Research Laboratory,
         Office of Research & Development.

         Thus, the objective of this handbook is to provide
         information to the small system operator, manager,
         and/or owner (you might be all of these) about
         different approaches to providing safe and affordable
         drinking water to your community.
            This handbook includes the following information:

            •   Common types of contaminants found in drinking
                water;
            •   Common water supply problems and
                recommended solutions;
            •   Applicable regulations, monitoring and reporting;
            •   Common regulatory violations;
            •   Treatment technologies most likely to work on a
                variety of contaminants;
            •   Specific information about innovative filtration
                and disinfection technologies;
            •   Information on Point-of-Use/Point-of-Entry
                systems;
            •   Information regarding remote monitoring and
                control of systems  from off-site locations (as well
                as filing state compliance reports on time);
            •   Real-world "lessons learned";
            •   Information about funding and technical resources
                to implement suitable technologies that meet
                applicable regulations; and
            •   Sources of additional information.
Figure 7-7.  EPA Test & Evaluation Facility, Cincinnati, OH.

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Small Drinking Water Systems Handbook

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                                                          Small Drinking Water Systems Handbook
2.0  Contaminants in  Drinking  Water
Water is the universal solvent, and most materials
will eventually dissolve in it. Water found in nature
generally contains a variety of contaminants such as
minerals, salts, heavy metals, organic compounds
(compounds that contain carbon and can occur
naturally or be man made, such as gasoline, dry
cleaning solvents, or pesticides); radioactive residues;
and living (microbiological) materials, such as
parasites, fungi, and bacteria.  These materials enter
water through natural processes, such as contact with
rocks, soil, decaying plant and animal matter, and
other materials. Human and animal wastes are the
primary contributors to microbiological contamina-
tion of water.  Industrial and agricultural sources can
also introduce chemical, pesticide, and herbicide
residues into water. [1]

When most people see or hear the word "contami-
nated," it signals danger or disease. However, EPA
defines a contaminant as "any physical, chemical,
biological, or radiological substance or matter in
water." Whether water is safe to drink depends on the
specific contaminants it contains, how much of each
contaminant is present,  and how these contaminants
affect human health.

For example, cloudy or slightly off-color water
sometimes may not be dangerous to drink, while
water that is perfectly clear may contain tasteless,
odorless, and colorless contaminants that cause
serious health effects. Similarly, some substances in
small concentrations, such as iron, are good for
human health.  Others, such as fluoride, may be
beneficial at low levels and cause health problems  at
higher levels.

Therefore, the PWS  source(s) must be protected from
harmful levels of contamination. The PWSs typically
treat the raw source water by filtration and disinfec-
tion. Disinfection is usually achieved by applying
chlorine or commercial bleaches. Combined filtra-
tion/disinfection treatment is usually  sufficient to
remove visible contaminants  and kill most bacteria/
viruses. However, too little filtration and disinfection
can result in a higher risk of a wide variety of
stomach and intestinal illnesses. Too much disinfec-
tant with too little filtration can result in the forma-
tion of disinfection byproducts (for example,
trihalomethanes) and a higher risk of cancer. There-
fore, it is important to have technologies in place to
monitor and enhance the treatment system operation,
thereby improving the overall water quality provided
to consumers.
Federal and/or state regulations are designed to
implement the following four basic strategies to
safeguard the quality of our drinking water:

•  Source Protection - Regulations are
    designed to prevent the contamination of
    source water, such as lakes, rivers and water
    wells that PWSs use. The government
    regulates land-use and the construction-
    location^) of water treatment facilities to
    control potential source(s) of pollution from
    contaminating source water.

•  Maximum Contaminant Levels (MCLs)
    and Maximum Contaminant Level Goals
    (MCLGs) - The MCLs are the highest level
    of a particular contaminant that is allowed in
    drinking  water. MCLGs are the highest level
    of a contaminant in drinking water below
    which there is no known or expected risk to
    health. MCLs are Federally enforceable
    standards, while MCLGs are non-enforceable
    guidance.

•  Treatment Technology (TT) - Most PWS s
    use some form of TT, so that the water will
    be palatable and safe to drink. Many systems
    (but not all) require routine disinfection as a
    safeguard against bacterial or  viral
    contamination.

•  Monitoring/Reporting (M/R) - M/R is
    critical for ensuring compliance with the
    various regulatory requirements.  Monitoring
    and reporting is essential in letting you know
    whether your system  is working properly and
    protecting your customers. Regulations
    typically require PWSs to routinely sample
    treated (or finished) water, and submit the
    samples to the state or local agencies. The
    submitted samples are tested for a broad
    range of  potential contaminants. If
    unacceptable levels of contaminants are
    found, the water supply owner or operator is
    legally responsible for informing the people
    who use  the water, and taking  steps to
    eliminate potential health hazards. The
    frequency of M/R activity varies depending
    upon location and system size.
                                                [2]

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Small Drinking Water Systems Handbook

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                                                       Small Drinking Water Systems Handbook
  3.0  Common  Water Supply  Problems
         and  Recommended  Solutions
  It is important to be able to identify common water
  supply problems because testing for every possible
  harmful contaminant (petroleum products, pesticides,
  heavy metals, bacteria, nitrate, volatile organic
  compounds, radioactive substances, etc.) is very
  expensive.  Therefore, it is important to be able to
  identify the potential contaminant and request a
  specific laboratory test. Table 3-1 provides general
  guidance on conditions that may prompt you to have
  your water tested.  Generally speaking, if your water
  changes taste, odor, or color suddenly, you may want
  to contact the local health department, state, or EPAs
  regional office for advice before you begin paying for
  any tests.

  Test samples should always be sent to a certified
  laboratory. The laboratory provides the test results in
  a report format that typically indicates the amount of
  a specific contaminant in your water sample ex-

For a List of Links to Certified Laboratories:
  www.epa.gov/safewater/faq/sco.html
pressed as a concentration, i.e., a specific weight of
the substance in a specific volume of water (e.g.,
milligrams/liter or mg/1). The test results also may
use other symbols and abbreviations. The laboratory
may also report the finding as "bdl" (below detection
limit) or "nd" (not detected) or a numerical result
using the symbol for "less than" (<). For example, if
your report lists a result of <0.03 mg/1 for arsenic,
this means that 0.03 mg/1 [milligrams per liter] is the
detection limit of the test for arsenic, and the water
had less than 0.03 mg/1 arsenic in it, if at all.

     The test result provided by the laboratory
should then be compared to the federal standards
(MCLs, MCLGs, etc.) and to other guidance num-
bers, such as health advisories, to assess the potential
for health problems. Health advisories specify levels
of contaminants that are acceptable for drinking
water over various lengths of time: one-day, ten-day,
longer-term  (approximately seven years), and lifetime
exposures (essentially the same as MCLGs).  These
standards are not legally enforceable, and typically
the numbers change as new information becomes
Table 3-1. Troubleshooting/Testing for Common Water Supply Problems [1]
Conditions or nearby activities
Recurrent gastrointestinal illness
Distribution system and/or household plumbing contains
lead
Radon in indoor air or region
Scaly residues and/or soaps do not lather
Stained plumbing fixtures, laundry
Objectionable taste or smell (such as rotten egg odor)
Water is cloudy, frothy, or colored
Corrosion of pipes, plumbing
Rapid wear of water treatment equipment
Nearby areas of intensive agriculture
Nearby coal, other mining operation
Gas drilling operation nearby
Gasoline or fuel oil odor
Nearby industrial activities
Dump, landfill, factory or dry-cleaning operation nearby
Salty taste and seawater, or a heavily salted roadway
nearby
Recommended test
Coliform
pH, alkalinity, hardness, lead, copper
Radon
Hardness
Iron, copper, manganese
Hydrogen sulfide, lead, copper, cadmium, pH, alkalinity,
hardness, metals
Color, detergents
pH, lead, copper, cadmium, alkalinity
pH, lead, copper, cadmium, alkalinity, hardness
Nitrate, pesticides, coliform bacteria
Metals, pH, lead, copper, cadmium
Chloride, sodium, barium, strontium
Volatile organic compounds (VOCs)
VOCs, synthetic organic compounds (SOCs)
VOCs, pH, sulfate, chloride, metals
Chloride, Total Dissolved Solids (IDS), sodium

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Small Drinking Water Systems Handbook
available. However, if MCLs are not being met and
the treatment system is working optimally, alternative
treatment technologies should be explored. Section
6.0 provides a brief overview of treatment technolo-
gies and their suitability to treat certain type(s) of
contaminants.

Emergency water purification
Microbiological contamination of a PWS may come
from the failure of a disinfection system, a cross
connection (a wastewater pipe gets connected to a
water pipe), a breach/break in the piping  system
(which allows non-treated water into the piping), or a
contaminated source (as in a well).  In the event of an
emergency, or due to a general concern over the
potential contamination of a drinking water source,
simple measures can be taken to disinfect sufficient
quantities of water to  satisfy basic household needs
until the crisis is resolved.  PWS Operators should
notify their customers about drinking water emer-
gency situations in the manner specified by their local
or state agency.  The operator should also advise their
customers of emergency water purification methods
under such circumstances.  Emergency water purifi-
cation methods include heat and chemical treatment.

Heat Treatment

1.  Strain water through a clean cloth into a clean
    pot to remove any sediment and/or floating
    debris.

2.  Heat and bring to a rolling boil for 1 full minute
    or more.  Allow the water to cool, and transfer it
    to a clean covered container. Refrigerate if
    possible. (Remember, at higher elevations,  water
    boils at lower temperatures and boiling may not
    treat parasites or  bacteria. Under such scenarios,
    chemicals or pressure cookers should be used.) [3]

Chemical Treatment*

Several chemical treatment alternatives are available
for emergency water disinfection. See Table 3-2 for a
summary of these methods.  Chlorine, in various
forms, is used for chemical disinfection. [3] The
other popular disinfection method uses iodine, such
as,  the tincture of iodine and tetraglycine
hydroperiodide (iodine) tablets. In case of using a
manufacturer supplied tablets, the manufacturer's
instructions should be followed carefully.  This type
of purification is intended for short-term  use only.
Remember to keep all disinfectants  out of the reach
of children or anyone  that may not understand the use
of these chemicals.

Also, the data in Table 3-2 indicate the quantity of the
product(s) required to release 10 mg of chlorine or
iodine per liter of water.  Recommended contact time
Table 3-2. Emergency Disinfection Treatment for
Drinking Water (W-mg /liter dose, 30-min.
contact time) [4]
Commercial
Product
Hypochloride
pellets
Iodine or
chlorine
tablets
Laundry
bleach
Tincture of
iodine
Available
Disinfectant
(%)
70
1.0-1.6
5.3
2
Disinfectant
Quantity
1 tablet
2 tablets
1
tablespoon
1
tablespoon
Gallons
Treated
80
0.25
20
8
is at least 30 minutes to ensure maximum disinfec-
tion. The following is a recommended method for
disinfection using chlorine or iodine tablets.

1.   Using chlorine tablets: Strain the water and fill a
    gallon-sized milk jug to approximately % full.
    Add six (6) drops of chlorine (household bleach)
    if the water is clear, or twice that amount if the
    water is cloudy. Shake vigorously and allow it
    to stand for 30 minutes. A slight odor of
    chlorine should be present.  Poorly strained
    water (i.e., water with debris) or water that is
    contaminated with very small particles or
    bacteria (and may be cloudy or clear) will use
    more chlorine. Therefore, it is  very important to
    use the proper amount of chlorine.  A basic pool
    grade chlorine test kit can be used to measure
    residual chlorine or simply smell the water. If
    there is no scent of chlorine, then repeat the
    dosage and let the water stand for an additional
    15 minutes.

2.   Using tetraglycine hydroperiodide (iodine)
    tablets, and iodine taste and odor neutralizing
    (ascorbic acid) tablets: Strain the water and fill a
    quart or liter container (canteen). Figure 3-1
    shows a picture of a canteen. Add two (2) iodine
    tablets to the container. Cap the container
    loosely to allow a small amount of leakage.
    Wait five (5) minutes (the tablets will dissolve
    but note that the tablets do not have to
    completely dissolve to be effective) and shake
    the container to allow the screw threads to
    moisten, then tighten the cap. Wait for thirty (30)
    minutes before drinking the water.  If after 30
    minutes the taste and odor of the  iodine is a
    problem,  then use two (2) tablets of ascorbic
    acid per liter of water to neutralize the iodine.
    Never add the iodine  and the ascorbic acid at the
    same time, this will stop the disinfection.

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                                                                Small  Drinking Water Systems Handbook
Figure 3- 7.  Canteen and tablets for emergency purification
using iodine.
       3.   Keep the water in a covered container.
           Refrigerate if possible.

       * Note: Certain organisms, such as Giardia and
              Cryptosporidium, are known to be chlorine
              and iodine resistant. Consequently, the heat-
              treatment method may be more reliable
              overall.

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Small Drinking Water Systems Handbook


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                                                          Small Drinking Water Systems Handbook
  4.0  Regulatory  Overview
  Prior to 1974, each state ran its own drinking water
  program and set standards that had to be met at the
  local level. As a result, drinking water protection
  standards differed from state to state. On December
  16, 1974, Congress enacted the original Safe Drink-
  ing Water Act (SDWA).  The SDWA was designed to
  protect public drinking water supplies from "harmful
  contaminants." Congress gave EPA the authority to
  establish acceptable or "safe" levels for known or
  suspected drinking water contaminants and to design
  a national drinking water protection program. Since
  then, EPA has set uniform nationwide minimum
  standards for drinking water by promulgating the
  National Primary Drinking Water Regulations
  (NPDWR) and Secondary Drinking Water Regula-
  tions (SDWR). State public health and environmental
  agencies have the primary responsibility for ensuring
  that the PWS meet federal drinking water quality
  standards (or more stringent ones as required by the
  state). [1]

  Between 1974 and 1986, EPA developed MCL
  standards under the NPDWR for 22 contaminants.
  Since 1986, EPA has issued seven major rules that
  establish standards for either a specific contaminant
  (83 in total) or groups of contaminants.

  In 1996, the SDWA was changed again.  Among the
  many changes to the SDWA, the 1996 amendments
  added provisions to provide funding to communities
  for drinking water mandates, focus regulatory efforts
  on contaminants posing health risks,  and added some
  flexibility to the regulatory process.
    To Find Out More About the SDWA:
 www.epa.gov/safewater/sdwa/sdwa.htm/
www.epa.gov/safewater/regs/swtr/ist.htm/
  The EPA is now required to select at least five new
  candidate contaminants to consider for regulation
  every five years. This list of contaminants is known
  as the Contaminant Candidate List (CCL). The new
  law also requires EPA to set MCLGs for each
  contaminant. MCLG is the level of a contaminant in
  drinking water below which there is no known or
  expected risk to health. MCLGs allow for a margin of
  safety and are non-enforceable public health goals from
  a regulatory perspective. EPA must then set an MCL as
  close to the MCLG as is "feasible" using the best
  available technology (BAT), taking costs into consid-
  eration (for MCL and MCLG definition, see box on
  page 3).
The SDWA standards are enforced through federal
and/or state regulations requiring PWSs to test for
contaminants and install new types of treatment
technologies if the test results indicate the presence
of contaminants in the treated water.
   To Find Out More About The MCLs and NPDWR:
         www. epa.gov/safewater/mcf.htm/
EPA also publishes standards for nuisance contami-
nants under the SDWR. The Secondary Maximum
Contaminant Levels (SMCLs) are concentration
limits for nuisance contaminants and physical
problems, such as offensive taste, color, odor,
corrosivity,  etc. The secondary standards are not
enforced, and PWSs are not required to test for and
remove secondary contaminants. However, these
standards are useful guidelines for PWS operators
who want to ensure that their water will be suitable
for all household uses. Typically, water utilities
receive more complaints because their water tastes or
smells funny, so these secondary standards should not
be ignored.
   To Find Out More About The SMCLs and SDWR:
 www.epa.gov/safewater/consumer/2ndstandards.html
It is important to understand that the regulations you
are responsible for depends upon which category of
small system you fall under. There are approximately
170,000 community water systems (CWS) and non-
community water systems (NCWS) in America.
NCWSs serve transient and non-transient populations
(see box on page 10). As you can see in Table 4-1,
small and very small systems account for the vast
majority of systems in the U.S. (>86%). [2]

PWSs derive their source water from both ground
and/or surface water. Table 4-2 describes the source
of water by system size and population served. As
you can see, the vast majority of systems use ground
water as their source of drinking water  (153,697 vs.
14,136); however, the majority of people served are
drinking river and lake water (179.9 vs. 103.9
million). Also,  almost 100% of non-community
systems are small.

Although the federal government defines "small
systems" as those serving fewer than 10,000 consum-
ers, it also recognizes that there is a quite a difference
between the "larger" small systems and the "smaller"

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      Small Drinking Water Systems Handbook
      There are two main categories of PWSs:

      1)   Community Water Systems (CWS) - CWSs
           provide drinking water to the same people
           year-round. Today, there are approximately
           54,000 CWSs serving more than 250 million
           Americans. All federal drinking water
           regulations apply to these systems.

      2)   Non-Community Water Systems (NCWS) -
           NCWSs serve customers on less than a year-
           round basis. NCWSs are, in turn, divided into
           two sub-categories:

           Non-transient (NTNCWS): Those that serve
           at least 25 of the same people for more than
           six months in a year but not year-round (e.g.,
           schools or factories that have their own water
           source);  most drinking water regulations
           apply to the 20,000 systems in this category.

           Transient (TNCWS): Those that provide
           water to places like gas stations and
           campgrounds where people do not remain for
           long periods of time; only regulations that
           control contaminants posing immediate
           health risks apply to the 96,000 systems in
           this category.                            /-o?
      ones that serve only a few hundred consumers. The
      1996 SDWA Amendments mandated that information
      about treatment technology performance and
      "affordability" be developed for the following size
      categories:

      •  3,301-10,000 people (medium)
      •  501-3,300 people (small)
      •  25-500 people (very small)

      Affordability criteria are based on a threshold of
      2.5% of the median household income (MHI).
      Nationally, the MHI is currently about 0.7% for the
      three size categories (Table 4-3).  Thus, any improve-
      ments to a small system cannot increase the annual
      cost of drinking water per household beyond the
      affordability threshold of 2.5%  of the MHI. For
      example, a drinking water system serving a popula-
      tion between  25-500 cannot put in improvements that
      raise the annual cost per household by more than
      $559 annually per household.  [5]

      The 1996 SDWA Amendments not only set in motion
      the development of a variety of new rules, but a new
      approach to setting future regulations. Of most
      concern to small systems is that they are ultimately
      going to be required to meet the same criteria that the
Table 4-1. Size Categories of Public Water Systems [2]
System Size
(population served)
Very Small
Small
(501 - 3,300)
Medium
(3,301 - 10,(
Large/Very Large
(>10,001)
Percent of Community
Water Systems
1980
67
22
6
5
1985
63
24
7
6
1990
63
24
7
6
1995
61
25
8
7
Table 4-2. Distribution of Water Systems [2]
System Type

NTNCWS
TNCWS
Surface
Water
Systems
11,403
821
1,912
People
Served
(millions)
178.1
.9
.9
Ground
Water
Systems
42,662
19,738
91,298
People
Served
(millions)
85.9
6.0
12.0
larger, more affluent systems do. Table 4-4 provides
the general sample monitoring schedule for small
systems.  Table 4-5 summarizes the current (2001)
and proposed regulations, their goal, and the  specific
types and sizes of small systems affected.  Note that
these requirements may vary by state and is depen-
dent upon the size or type of PWS.

A full discussion of each of these regulations and its
requirements for specific systems is beyond the scope
of this document. The most common types of
violations are discussed in Section  5.0 of this hand-
book.
10

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                                                             Small Drinking Water Systems Handbook
Table 4-3. National Level Affordability Criteria [5]
System Size
(Population Served)
25 - 500
501 - 3,300
3,301 -10,000
Baseline
MHI
($/year)
$30,785
$27,058
$27,641
Water Bills
($/hh/year)

$184
$181
Water Bills
(% MHI)
0.69%
0.68%
0.65%
Affordability
Threshold
(2.5% MHI)

$676
$691
Available Additional
Expenditure
($/hh/year increase)

$492
$474
MHI - median household income
hh - household
Table 4-4. General Sample Monitoring Schedule for Small Systems3-11
Contaminant
Minimum Monitoring Frequency
Acute contaminants - Immediate risk to human health
Bacteria
Nitrate
Protozoa and viruses
Monthly or quarterly, depending on system size and type
Annually
Future requirements for the Ground Water Rule may require monitoring and
Chronic contaminants - Long-term health effects if consumed at certain levels for extended periods of time
Volatile organics (e.g., benzene)
Synthetic organics (e.g., pesticides)
Inorganics/metals
Lead and copper
Radionuclides
Ground water systems - quarterly for the first year, annually for years 2 and 3,
after that depending on results; surface water systems - annually
Larger systems, twice in 3 years; smaller systems, once in 3 years
Ground water systems - once every 3 years; surface water systems - annually
Annually
Once every 4 years
aGeneral requirements may differ slightly depending on the State, size or type of drinking-water system.
"Source:  EPA Office of Ground Water and  Drinking Water (OGWDW) web site.
                                                                                                        11

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      Small Drinking Water Systems Handbook
Table 4-5. Small System Regulatory Summary [2] [6] [7] [8]
Regulation
Microbiological (National Primary
Drinking Water Regulations
Volatile Organic Chemicals
(NPDWR)
Radionuclides
Radon
Inorganic Chemicals (NPDWR)
Total Coliform Rule
Surface Water Treatment Rule
Lead and Copper Rule
Arsenic
Ground Water Rule
Long Term 1 Enhanced Surface
Water
Filter Backwash Rule
Stage 1 Disinfectants/Disinfection
By-Products Rule (D/DBP)
Long Term 2 Enhanced Surface
Water Rule and Stage 2 D/DBP
Rules
Contaminant Candidate List (CCL)
Summary
Coliform MCL
MCLsb
MCLsb
MCLsb
MCLsb
No more than 5% of samples positive for
Coliform; Distribution system sampling
3 Log (99.9%) removal of Giardia,
4 Log (99.99%) virus inactivation
Filtration treatment specified
Distribution System Action Levels
MCLsb
Appropriate use of disinfectants, multi-
barrier approach
2 Log removal (99%) of Cryptosporidium,
0.3 NTU for Turbidity; TOCC reductions for
precursor removal
Recycling filter backwash with treatment
Total Trihalomethane MCL reduced to 0.08
mg/L; 5 Haloacetic acidsd total of 0.060
mg/L; chlorite MCL 1.0 mg/L; bromate
0.010 mg/L MCL; maximum residual
disinfectant levels set (MRDLG/MRDL)
To be enacted together to balance
microbial and disinfectant by-product
formation; Possible lowering of current
MCLs and distribution system
requirements
Possible new MCLs
What Systems are Affected?
All types and sizes
All CWSs and NTNCWSs
All types and sizes
All types and sizes
All CWSs and NTNCWSs; transient
systems exempt except for
nitrates, nitrites
All types and sizes
All surface water and ground water
under the direct influence of
surface water
All CWSs and NTNCWSs
All CWSs and NTNCWSs
All systems using ground water as
source
All surface water and ground water
under the direct influence of
surface water
All conventional (flocculation/
coagulation/sedimentation) and
direct filtration systems
CWSs and NTNCWSs that use a
chemical disinfectant
All types and sizes
All types and sizes
       aNephelometric Turbidity Unit
       bFor MCL information, please visit: www.epa.gov/safewater/mcl.html
       Total Organic Carbon
       dincludes dichloroacetic acid, trichloroacetic acid, monochloroacetic acid, bromoacetic acid, and dibromoacetic acid
12

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5.0  Common Violations
                                                         Small Drinking Water Systems Handbook
Generally, larger PWSs have more resources and
lower costs per customer to comply with regulations.
Thus, larger PWSs incur fewer violations, despite the
fact that larger PWSs have historically complied with
more regulations than smaller systems.

Small systems, however, account for the vast majority
of violations for both MCLs and M/R.  According to
a 1993 survey, small treatment systems serving fewer
than 10,000 people represented 94% of all water
supply systems in America and served only 21% of
the national population.  Also,  these Small Systems
accounted for 93% of the MCL violations and 94% of
the M/R violations.  The majority of the MCL
violations involved microbial parameters. M/R
violations could be the result of no sampling being
performed, insufficient recording of data, or failure to
report the data. The number of chemical contamina-
tion violations were also exceedingly high for small
utilities. (See Tables 5-1 and 5-2 below).

EPA has also identified M/R violations associated
with human errors related to operators' handwriting,
There are three main types of violations:

Maximum Contaminant Level (MCL) violation -
MCL violation occurs when tests indicate that the level
of a contaminant in treated water is above EPA's or the
state's legal limit (states may set standards equal to, or
more protective than, EPA's). These violations indicate a
potential health risk, which may be immediate or long-
term.

Treatment Technique (TT) violation - TT violation
occurs when a water system fails to treat  its water in the
way EPA prescribes (for example, by not disinfecting).
Similar to MCL violations,  TT violations indicate a
potential health risk to consumers.

Monitoring/Reporting (M/R) violation  - M/R viola-
tion occurs when a system fails to test its water for
certain contaminants, or fails to report test results  in a
timely fashion. If a water system does not monitor its
water properly, it is difficult to know whether or not the
water poses a health risk to consumers.              m
Table 5-1. Total Coliform Bacteria Violations for the Period October 1, 1992 through December 31, 1994 [9]
Number of
Consumers
<500
501 - 3,300
3,301 -10,000
> 10,000
Systems with Violations
Number of Systems
10,509
1,938
592
487
Percent of
Total (%)
29.5
13.4
14.4
14.4
Violations by Source Water
Ground Water
Systems (%)
95.0
84.8
71.8
59.1
Surface Water
Systems (%)
5.0
15.2
28.2
40.9
Table 5-2. Chemical Contamination Violations for the Period October 1, 1992 through December 31, 1994 [9]
Number of
Consumers
<500
501 - 3,300
3,301 -10,000
> 10,000
Systems with Violations
Number of Systems
531
162
25
15
Percent of
Total (%)
1.5
1.1
0.6
0.4
Violations by Source Water
Ground Water
Systems (%)
96.4
73.5
60.0
33.3
Surface Water
Systems (%)
3.6
26.5
40.0
66.7
                                                                                                     13

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      Small Drinking Water Systems Handbook
      such as the way a person records "D," "P," entries into
      the reporting document.

      In the past, this type of violation was one of the
      leading causes for water systems being out of
      compliance in the Commonwealth of Kentucky.
      Recently, through a certification course, Kentucky
      has provided handwriting suggestions to the small
      system operators, which apparently have reduced the
      number of M/R violations there. However, there is no
      way to estimate the number of erroneous entries due
      to penmanship. Operators should remember that a
      hand-written report is only as good as the penman-
      ship of the  person filling out the document.
Small System operators need to take time and care
when filling out the reporting documents. The Com-
monwealth of Kentucky identified hand-writing
problems associated with report forms for bacteriologi-
cal analysis of water samples sent to various laborato-
ries.

For example, Small System operators may first fill out
parts of the form. After analysis, the laboratory
(another person, company, etc.) completes the remain-
ing information on the form and forwards a copy to the
state (primacy) agency. The portion the operator fills
out has a box to identify the type  of sample collected.
Kentucky uses letter codes to identify the collected
sample: the two relevant codes are "D" for "distribu-
tion" and "P" for "plant" sample.  Each PWS is re-
quired to send in an assigned number of "distribution"
samples each month. If an operator is not careful and
enters a "D" with a small tail, it can appear as a "P."
Even though the primacy agency knows that the PWS
purchases water and does not even have a treatment
plant, the form still appears to have  a "P" and will list
the water system as out of compliance (M/R) until the
Small System operator that filed the form makes
corrections.
14

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                                                          Small Drinking Water Systems Handbook
6.0  Treatment Technologies
When the SDWA was reauthorized in 1996, it
addressed small system drinking water concerns and
required EPA to assess treatment technologies
relevant to small systems serving fewer than 10,000
people.  The 1996 SDWA Amendments also identified
two distinct classes of treatment technologies for
small systems:

•    Compliance technologies, which may refer to:

       (1)  a technology or other means that is
           affordable and that achieves compliance
           with the MCL, and

       (2)  a technology or other means that satisfies
           a treatment technique requirement.

•    Variance technologies that are only specified for
     those system  size/source water quality
     combinations for which there are no listed
     compliance technologies. [10]

Thus, listing a compliance technology for a size
category/source water combination prohibits listing
variance technologies for that combination. While
variance technologies may not achieve compliance
with the MCL or treatment technique requirement,
they must achieve the maximum reduction or inacti-
vation efficiency affordable considering the size of
the system and the quality of the source water.
Variance technologies must also achieve a level of
contaminant reduction that protects public health.
Possible compliance technologies include packaged
or modular systems and point-of-use (POU) or point-
of-entry (POE) treatment units. POU/POE systems
are discussed further in  Section 7 of this handbook.
[11]

The  1996 SDWA Amendments did not specify the
format for the compliance technology lists and stated
that the variance technology lists can be issued either
through guidance or regulations. Rather than provide
the compliance technology list through rule-making,
EPA provided the listing in the form of guidance
without any changes to existing rules or passing new
ones. This guidance, which is summarized in Table
6-1,  may be found in:

     Small System Compliance Technology List for
     the Surface Water Treatment Rule and Total
     Coliform Rule (EPA 815-R-98-001)

-    Small System Compliance Technology List for
     the Non-Microbial Contaminants Regulated
     Before 1996 (EPA  815-R-98-002)

     Variance Technology Findings for Contaminants
   In anticipation of the states' needs for innovative and
   cost-effective small system treatment technology, the
   EPA Water Supply and Water Resources Division
   (WSWRD) has focused on the smallest of these
   systems in the 25-500 population range and on those
   technologies that are easy to operate and maintain.
   WSWRD is a division of EPAs Office  of Research &
   Development, National Risk Management Research
   Laboratory.   Alternative treatment systems/technolo-
   gies (package plants) are perceived as "high tech"
   and are sometimes more expensive to purchase than
   state-accepted conventional technologies.  However,
   in many cases, alternative treatment systems/
   technologies are easier to operate, monitor, and
   service, and less expensive to maintain and service
   in the long-run.

     Regulated Before 1996 (EPA 815-R-98-003)

A matrix of contaminants that are regulated under the
SDWA and possible treatment technologies for water
containing these contaminants  are shown in Table 6-2.

Of the compliance technologies listed in Table 6-1, a
majority of the EPA WSWRD small systems research
has focused on evaluating "packaged" filtration and
disinfection technologies that are most useful to
small system operators. This handbook is  a product  of
ongoing research conducted by the WSWRD to
compile and evaluate the best available technology so
as to provide information about cost-effective
drinking water treatment technology options to the
small system operators. Filtration efforts  have
focused on evaluating various bag filters,  cartridge
and membrane filters. Disinfection techniques
evaluated included a variety of onsite chlorine
generators and packaged ultraviolet (UV)/ozonation
plants. Details regarding these efforts are  presented
below.

Filtration
Filtration is the removal of particulates, and thus
some contaminants, by water flowing through a
porous media. Filtration is considered to be the most
likely and practical treatment process or technology
to be used for removing suspended particles and
turbidity from a drinking water supply. Federal and
state laws require all surface water systems and
systems under the influence of surface water to filter
their water. Filtration methods include slow and
rapid sand filtration, diatomaceous earth filtration,
direct filtration, membrane filtration, bag  filtration,
and cartridge filtration. As discussed earlier, the
research at the EPA T&E Facility (Figure  1-1)
                                                                                                      15

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       Small  Drinking Water Systems Handbook
Table 6-1. Surface Water Treatment Compliance Technology Table [11]
Disinfection Technologies
Unit Technologies
Free Chlorine
Ozone
Chloramines
Ultraviolet Radiation
Chlorine Dioxide
Removals:
Log Giardia & Log Virus w/CT's
indicated in ( )
3 log (104a) &4 log (6)
3 log (1.43) &4 log (1.0)
3 log (1850) &4 log (1491)
1 log Giardia (80-120), better for
Cryptosporidium, & 4 log viruses
(90-140) (mWsec/cm2 doses in
parentheses)
3 log (23) & 4 log (25)
Comment
Requires basic operator skills. Better for water systems with
good quality source water, low in organics and
iron/manganese. Concerns with disinfection byproducts.
Storage and handling precautions required.
Requires intermediate operator skills. Ozone leaks can be
hazardous. Does not provide residual disinfection protection
for distributed water. Concerns with disinfection byproducts.
Requires intermediate operator skills. The ratio of chlorine to
ammonia must be carefully monitored. Requires large CT.
Requires basic operator skills. Relatively clean water source
necessary. Does not provide residual disinfection protection
for distributed water.
Requires intermediate operator skills. Better for larger
drinking water systems. Storage and handling precautions
required. Concerns with disinfection byproducts.
Filtration Technologies
Unit Technologies
Conventional Filtration and
Specific Variations on
Conventional
Direct Filtration
Slow Sand Filtration
Diatomaceous Earth Filtration
Reverse Osmosis
Nanofiltration
Ultrafiltration
Microfiltration
Cartridge/Bag/Backwashable
Depth Filtration
Removals:
Log Giardia & Log Virus
2-3 log Giardia & 1 log viruses
0.5 log Giardia & 1-2 log viruses
(and 1.5-2 log Giardia with
coagulation)
4 log Giardia & 1 -6 log viruses
Very effective for Giardia (2 to 3-
log) and Cryptosporidium; low
bacteria and virus removal
Very effective, absolute barrier
(cysts and viruses)
Very effective, absolute barrier
(cysts and viruses)
Very effective Giardia, >5-6 log;
Partial removal viruses
Very effective Giardia, >5-6 log;
Partial removal viruses
Variable Giardia removal &
disinfection required for virus
removal
Comment
Advanced operator skills required. High monitoring
requirements. May require coagulation, flocculation,
sedimentation or flotation as prefiltration. Will not remove all
microorganisms.
Advanced operator skills required. High monitoring
requirements. May require coagulation, flocculation,
sedimentation, or flotation as prefiltration. Will not remove
all microorganisms.
Requires basic operator skills. Most effective on high quality
water source. Will not remove all microorganisms.
Requires intermediate operator skills. Good for source water
with low turbidity and color. Will not remove all
microorganisms.
Requires intermediate to advanced operator skills, depending
on the amount of pretreatment necessary. Post disinfection
required under regulation. Briny waste can be toxic for
disposal.
Requires intermediate to advanced operator skills, depending
on the amount of pretreatment necessary. Post disinfection
required under regulation.
Requires intermediate to advanced operator skills, depending
on the amount of pretreatment necessary. Post disinfection
required under regulation.
Requires intermediate to advanced operator skills, depending
on the amount of pretreatment necessary. Disinfection
required for viral inactivation.
Requires basic operator skills. Requires low turbidity water.
Disinfection required for viral inactivation. Care must be
taken toward end of bag/cartridge life to prevent
breakthrough.
        aA 3 log (104) removal indicates that 99.9 % (or three 9's) of Giardia was removed in 104 minutes of contact time (CT) with free
        chlorine disinfection. Similarly, 1 log would indicate only one-9 removal i.e., 90% removal and a 4 log removal indicate 99.99%
        removal. CT is a measurement of the length of time it takes for a disinfectant to kill, for example, giardia lamblia, at a specified
        disinfectant concentration. If the disinfectant concentration is half the specified dosage in a CT table, the contact time should be
        double the specified number in the CT table to ensure proper disinfection and vice-versa (twice the specified dosage requires only
        half the contact time).  CT requirements also assume there is sufficient mixing of the disinfectant and water and are dependent on
        the pH and temperature of the water.
16

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Small Drinking Water Systems Handbook
Table 6-2. Regulated Contaminant List (partial) and Possible Removal Technologies [10]
Microbial Contaminants and Turbidity
Turbidity (Suspended material)
Coliform Bacteria, Viruses,
Cryptosporidium oocysts and Giardia
cysts
Filtration
Turbidity reduction by filtration as noted above followed by disinfection
Radioactivity
Beta particle and photon activity
Gross Alpha Particle activity
Radium 226 and Radium 228
Radon
Uranium
Mixed Bed Ion Exchange. Reverse Osmosis
Treatment method depends on the specific radionuclide (e.g., radium, radon
or uranium)
Cation Ion Exchange, Reverse Osmosis
Activated Carbon
Anion Ion Exchange, Activated Alumina, Microfiltration, Reverse Osmosis
Health-Related Inorganic Contaminants
Antimony
Arsenic (+3)
Arsenic (+5)
Organic Arsenic Complexes
Asbestos
Barium
Beryllium
Cadmium
Chromium (+3)
Chromium (+6)
Organic Chromium Complexes
Copper, Nickel
Fluoride

Mercury (+2)
Mercury (HgCIS -1)
Organic Mercury Complexes
Nitrate and Nitrite
Selenium (+4)
Selenium (+6)

Thallium
Microfiltration, Reverse Osmosis
Reverse Osmosis
Submicron Filtration, Anion Ion Exchange, Activated Alumina, Reverse Osmosis
Activated Carbon
Submicron filtration. Reverse Osmosis
Cation Ion Exchange, Reverse Osmosis
Submicron Filtration & Carbon, Activated Alumina, Cation Ion Exchange, Reverse Osmosis
Submicron Filtration, Cation Ion Exchange, Reverse Osmosis
Cation Ion Exchange, Reverse Osmosis
Anion Ion Exchange, Reverse Osmosis
Activated Carbon
Cation Ion Exchange, Reverse Osmosis
Activated Alumina, Reverse Osmosis
Cation Ion Exchange, Submicron Filtration & Carbon, Reverse Osmosis
Cation Ion Exchange, Submicron Filtration & Carbon, Reverse Osmosis
Anion Ion Exchange, Reverse Osmosis
Activated Carbon
Anion Ion Exchange, Reverse Osmosis
Submicron Filtration & Carbon, Anion Ion Exchange, Activated Alumina, Reverse Osmosis
Anion Ion Exchange, Activated Alumina, Reverse Osmosis
Anion Ion Exchange, Activated Alumina, Reverse Osmosis
Cation Ion Exchange, Activated Alumina
Health-Related Organic Compounds
Use Activated Carbon or Aeration to Remove the Following Contaminants
Adipates
Benzene
Carbon Tetrachloride
Dibromochloropropane
Dichlorobenzene (o-, m-, p-)
1,2-Dichloroethane
1,1-Dichloroethene
cis- and trans-1,2-Dichloroethene Tetrachloroethylene
1,2-Dichloropropane Toluene
Ethylbenzene 1,2,4- Trichlorobenzene
Ethylene Dibromide 1,1,1-Trichloroethane
Hexachlorocyclopentadiene 1,1,2-Trichloroethane
Monochlorobenzene Trichloroethylene
Styrene Trihalomethanes
Use Activated Carbon to Remove the Following Contaminants
Alachlor
Aldicarb
Aldicarb Sulfone
Aldicarb Sulfoxide
Altrazine
Benzo(a)anthracene (PAH)
Benzo(a)pyrene (PAH)
Benzo(b)fluoranthene (PAH)
Benzo(k)fluoranthene (PAH)
Butyl benzyl phthlate (PAH)
Carbofuran
Chlordane Lindane
Chrysene (PAH) Methoxychlor
2,4-D Oxamyl
Dalapon Pentachlorophenol
Di (2-ethylhexyl) adipate Picloram
Dibenz(a,h)anthracene (PAH) Polychlorinated Biphenyls
Glyphosate Simarzine
Heptachlor 2,3,7,8-TCDD (dioxin)
Epoxide Hexachlorobenzene Toxaphene
Indeno (1 ,2,3-c,d) Pyrene (PAH) 2,4,5-TP (Silvex)
                                    17

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       Small Drinking Water Systems Handbook
       focused on "packaged" bag, cartridge and ultrafiltra-
       tion units. The other filtration methods typically use
       natural filtration media (e.g., granulated media
       particles, such as carbon, garnet, or sand, alone or in
       combination). Bags and cartridge filtration media are
       commonly made from synthetic fibers designed with
       a specific pore size.  The type of filter media most
       suited for an application depends mainly on the
       impurities present in the source (raw) water.  Specifi-
       cally, the particle size of the impurity present in the
       raw water typically dictates the type of filter media.
       The particle sizes of common water contaminants and
       the filtration devices required for their treatment (or
       removal) are shown in Figure 6-1.

       If the source water contains particle (large size)
       impurities, prefiltration is generally applied in front
       of bag or cartridge type filters. Prefiltration removes
       the larger particulate material from the water stream
       by using coarse, often back-washable granular media.
       The prefilters protect the more expensive bag and/or
       cartridge type units from frequent "fouling."  Figure
       6-2 shows a picture of a clogged prefilter.

       A source water may contain turbidity, particles,  or
       organic material. These materials consume and
       compete for chemicals used in the treatment  process,
       such as chlorine. Thus, operators should find a
       mechanism to filter the particles,  turbidity or organic
       material out of the water. Filtration can remove
       certain types of color and particulate matter down to
       any micron size. Special microfiltration devices or
       submicron filters are capable of removing various
       bacteria, viruses, and protozoa.

       Bags and cartridge filters can be used to remove
       contaminants down to approximately the 1-micron
       particle size (l/10th the size of a human hair).
       However, a prefilter (such as another bag or cartridge
       filter of greater pore size) is typically recommended
       prior to using a submicron filter.  Microfiltration is
       used to remove particles in the 0.5 to 10 micron size
   Operators should find a mechanism to filter particles,
   turbidity or organic material out of the source water
   and should realize that each particle removed by a
   filter could be microscopic parasites such as the
   Cryptosporidium sp.  parasite.  Removing particles
   also allows the disinfectant to be more effective.
   However, the best option would be to find a good
   quality of source water, i.e., a source water that has
   very low particle counts, turbidity, or organic material.
range with the membrane acting as a simple sieving
device.  In ultrafiltration, nanofiltration, and reverse
osmosis processes, one stream of untreated water
enters the unit but two streams of water leave the
unit: one is treated water and the other is reject water
containing the concentrated contaminants removed
from the water. Microfiltration systems will remove
some microbes, such as protozoa and bacteria, but not
viruses. Unlike nanofiltration and reverse osmosis,
microfiltration cannot remove calcium and magne-
sium from water.  Ultrafiltration is used to remove
some dissolved material (such as large organic
molecules) from water. Particles down to 0.001 to
0.02 micron size range are removed.  Most microbial
contaminants are  removed including bacteria,
protozoa, and the larger virus sizes.  Nanofiltration is
used to remove particles in the 0.001 to 0.002 micron
size range, polyvalent ions, and smaller organic
molecules (down  to a molecular weight of about 200-
500 daltons).   Reverse osmosis (RO) can remove
most contaminants dissolved in water including
arsenic, asbestos, protozoa, pyrogens, sediment, and
viruses.  [12]

Performance Evaluation  of Filtration Media
Different vendors present filtration performance  data
in different ways, leading to some confusion. For
example, the pore size specification for a filter can be
the absolute or nominal pore size. Absolute size
generally refers to a 100% removal of solids above
Microns 
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                                                                   Small Drinking Water Systems Handbook
Figure 6-2. Clogged prefliter.

       the specified size rating on a single pass. Nominal
       pore size generally refers to an average pore size of
       the filter media itself and typically nominal values
       indicate a certain percent removal of particles of the
       specified size and higher.

       Different filters have different operating pressure
       ranges depending on the type of media, construction,
       flow rates, etc.  Filter performance may vary depend-
       ing on the change in pressures across the filter.  As a
       filter becomes clogged, the difference between the
       pressure coming into the filter and the pressure
       leaving the filter becomes larger and is a good
       operational tool to determine when a filter should be
       replaced, cleaned, or backwashed. Sudden change in
       the exiting pressure can mean a bag or cartridge has
       ruptured and is providing no protection.  The high
       pressure in the operating range typically  indicates
       that the media is clogged and the bag or cartridge
       needs to be "washed" or replaced.

       The performance of each filter can be judged based
       on the removal of turbidity, particle-count, and
       microbe (and/or surrogate) removal relative to its run-
       time. A number of evaluations have been conducted at
       the T&E Facility using Cryptosporidium and/or
       equivalent size micro-spheres (plastic beads).
       Turbidity is  defined as  an "expression of the optical
       property that cause light to be scattered and absorbed
       rather than transmitted in straight lines through the
       sample." Simply stated, turbidity is the measure of
       relative sample clarity or cloudiness (it is not associ-
       ated with color).  When a light beam passes through a
       sample of "turbid" water, the suspended solids scatter
       the light, thus reducing the intensity of the light
       beam.  This  reduction in intensity of the light beam is
       measured  optically/electronically using a turbidime-
       ter. Turbidity is reported in Nephelometric Turbidity
       Unit (NTU); typically,  the regulations require PWSs
       to supply water with turbidity less than 0.50 NTU.
However, the mere presence of turbidity cannot be
directly related to the presence of microbial organ-
isms; therefore, other measurements such as particle
counts might be performed.

Particle counting involves counting each particle
individually in a sample of water.  Various electronic
measuring devices are available that can be used to
count particles.  One can imagine the difficulty
associated with manually counting thousands of
microscopic particles.  Most particle counters have a
"sensing" zone that measures the particles individu-
ally. As a particle is detected, it is sorted into a
"channel" based on magnitude (or size).  Particle
counters are expensive ($20,000) and often difficult
to operate, thus limiting their usefulness to Small
System operators.

Also, different microbial organisms vary in size,
Crypto sporidium range between 3-7 micrometers in
size and Giardia range between 6-9 micrometers.
Typically, tests  are performed to either measure the
actual Crytosporidium removal, the removal of test
surrogates, such as microspheres or naturally occur-
ring spores.  The surrogate is considered to be the
equivalent for Crypto sporidium removal. EPA
evaluated the performance of different types of
filtration media by operating various filtration
systems under various "test" conditions. The evalua-
tion summaries for various types of filters are
presented in the following subsections.

Bag Filtration
Bag filtration systems are based on physical screen-
ing processes. If the pore size of the bag filter is
smaller than the microbe, some removal will occur.
Depending on the quality of the raw water, EPA
suggests a series of filters, such as sand or multimedia
filters followed by bag or cartridge filtration, to
increase particulate removal efficiencies and to
extend the life of the secondary filter. Bag filters can
be used as a pre-filter to other filters as well.

Bag filters are disposable, non-ridged replaceable
fabric units contained either singly in series or
parallel or grouped together in multiples within one
vessel.  The vessels are usually fabricated of stainless
steel (Figure 6-3) for corrosion resistance, strength,
cleaning, and disinfection.  Supply (non-treated or
treated) water can be introduced into the vessel from
the top, side, or bottom, and flows from the inside of
the bag to the outside.  Research conducted by EPA
has not shown any specific method of water introduc-
tion into the vessel to be superior to  others.  However,
there  are significant differences between manufactur-
ers  in the engineering design of closing devices and
gasket types used to seal the bag tightly into the
vessel and prevent filter by-pass.  Each operator
                                                                                                                  19

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       Small  Drinking Water Systems  Handbook
                Figure 6-3.  Typical bag filter.

       should be shown by the vessel vendor the proper fit of
       the filter and lid to the body "housing" before
       agreeing to purchase or set-up a bag filtration system.
       Improper filter installation can cause water hammer
       and can sometimes damage the bag. A vendor may
       sometimes claim that improper bag "installation" was
       the reason for poor performance of a bag filter (see
       box on page 23).

       Bag filters are designed in a variety of ways. They
       can be fabricated of multiple layers and varying
       materials. One of the most cost-effective benefits  of
       bag filters is their common use without costly
       chemical additions, such as coagulation, flocculation,
       or filter-coated chemicals. These filters have pore
       sizes designed into them to contain and capture
       oocysts, protozoa, or parasites Figure 6-4 is a picture
       of a bag filter that has been cut away to view the
       various layers and configuration. Caution should be
       taken when handling  spent filters due to the potential
       concentration of the debris, protozoan, parasite,  or
                                                              EPA found that different bags, even with the same
                                                              stock and lot numbers, can exhibit a wide range of
                                                              water treatment capacity. Some bags may treat
                                                              many thousands of gallons of water while others
                                                              may treat only a few hundred gallons of water.
                                                              Thus, although bags may be rated similarly, their
                                                              performance can vary significantly, and bag selec-
                                                              tion becomes more involved than a straightforward
                                                              matching of pore size and the size of the particle or
                                                              the turbidity to be removed from the water supply.
                                                              The selection of the best bag depends on the specific
                                                              water quality characteristics and treated water
                                                              (effluent) regulatory requirements or objectives.
oocyst.  If the operator suspects oocysts are in the
filter, then the operator should wear proper personal
protective equipment to remove the filter.  The filter
could then be placed in a secured location where it
can dry completely. The operator should then be able
to dispose of the filter normally.

Figures 6-5, 6-6, 6-7 and 6-8 show rupture and bypass
scenarios. Ruptures in fabric and/or gaps in heat
welded bags can allow particles to pass through into the
treated drinking water (as shown in Figure 6-5, with a
pen inserted to mark the tear, and in Figure 6-6).  A
bypass is typically associated with significant
discoloration of the bag.  Figure 6-7 shows discolora-
tion on both ends of the bag filter.  The most common
location for bypass is generally near the lid of each
filter housing as shown in Figure 6-8.

EPA has evaluated several types  of bag filters at the
T&E Facility. Different configurations of bag
filtration systems (see Table 6-3  and Figure 6-9) were
challenged under controlled turbidity levels and flow
rates. The research was not intended to compare
systems but to identify the most important design and
operational characteristics that provide for the most
economical application in various raw water situa-
tions. Important design considerations are bag
quality,  gasket integrity, and hydraulic reliability.
Operational factors include continuous vs. intermit-
tent operation, flow rate,  and pressure differential.
Turbidity challenges ranged from 1 NTU to 10 NTU.
Table 6-3. Bag Filter Characteristics (see Figure 6-9)
Bag Filter
1
2
3
Pore Size
3 micron (average)
3 micron (average)
99 % removal of 2.5 micron
95 % removal of 1 .5 micron
# of Layers
9
1
18
Surface Area (sq. ft)
41
2-3
35
Seam Const.
Sewn
Sewn
Sewn
20

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                                                                  Small Drinking Water Systems  Handbook
Figure 6-4. Cut-away of bag filter.

       Average % reduction ranged from 40% to 93%. Of
       course, at higher influent turbidity levels,  greater
       removals can be demonstrated but there seems to be a
       "best" (e.g.,  0.50 NTU) turbidity level that each brand
       of bag filter  can reach regardless of the initial influent
       quality.

       During initial start-up, removal was better and then
       settled into a fairly steady performance rate until near
       the end of the bag's life. Flow rate and starting water
       quality (or lack of) did not seem to be a major factor
       in filter performance.  Once a bag begins  to foul at 5
       to 10 pounds per square inch (psi) differential, the
       time until the bag must be replaced quickly de-
       creases. High NTU scenarios (>5  NTU) indicate the
       need for multiple filtration barriers in order to not be
       bankrupted by having to buy replacement  bags every
       few days. Bag rupture is more likely near  the end of
       the filter run as the pressure differential reaches its
       maximum.  Once a rupture or hole occurs, the
                                                           Figure 6-6. Bag filter showing fabric rupture.
Figure 6-7 and 6-8.  Bag filters showing discoloration
associated with bypass.
Figure 6-5. Bag filter showing rip in seam (where pen is
inserted).
Figure 6-9. Different configurations of bag filters tested.
(see Table 6-3)
                                                                                                                21

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       Small  Drinking Water Systems Handbook
       treatment barrier is gone with effluent water quality
       the same or worse than influent. The results indicate
       that for systems with little water storage, or without on-
       site/automatic operator control to stop flow at this point,
       it is critical to be conservative in estimating bag life.

       Particle count analyses were also performed simulta-
       neously. Figure 6-10 demonstrates that during the
       experiment, one of the bags removed nearly all
       particles greater than 8 micron in size, although not
       immediately after installation.  All bags in the study
       were rated with average pore sizes in the 2-5 micron
       range. Thus, a Small System operator must be aware
       that pore size only provides a general idea of the
       filter's capability. The raw water used in these
       experiments exhibit a majority of small (1-3 micron)
       particles whereas other water sources with turbidity
       made up of larger particles may be filtered better by
       bag filtration. Another operational characteristic
       observed for all filters was an initial loss of removal
       efficiency  and pressure differential when first turned
       on after having been out of operation for several
       hours. Within approximately 30 minutes, removal
       and pressure differential returned to the levels of the
       previous day. [14]

       A fourth bag was initially  tested with a 1 micron
       absolute pore size,  1 layer, and heat-welded seems
       but could only run for a few hours before becoming
       clogged.  It could however be used in series following
       one of the other bags.

       Cryptosporidium challenges  were also conducted
       along with the beads.  Table 6-4 summarizes all the
       contaminant challenges that took place over a range
       of flow rates, pressure differentials (bag age), and raw
       water loadings.  Although  Bag  3 showed the highest
       removal rates, it varied considerably  during filter runs
       and was the most likely to experience a rupture. Bag
       1 was extremely steady in its removal and would
       probably be easier to operate over time. [15]

       Figures 6-11 and 6-12 show the inner structure of a
       new and used bag (as viewed under an electron
       microscope).  It appears that as a bag continues to be
       used, the smaller particles (dirt) can work their way
                      Particle Size (microns)
Figure 6-10.  Influent vs Effluent Particle Counts

through the bag layers and ultimately pass through.

Bag filtration should not be used as a single barrier to
remove parasites, such as Cryptosporidium.  How-
ever, it can be used as a pretreatment step before
cartridge filtration to remove large particles and high
levels of turbidity to improve parasite removal and
then polish or treat with a disinfectant to remove any
microbial or  bacterial contaminant.
    15k U   XI,008
Figure 6-11. New bag.
                                              1 1 0702
Table 6-4. Bag Filtration Performance Summary [15]
Bag Filter System
Bag1
Bag 2
Bag 3
Percent Reduction
Beads or
Microspheres3
93%
50%
99.1%
Turbidity
80%
10%
93%
Particle Count"
95%
10%
97%
Cryptosporidium
94%
40%
99.94%
        a4.5 micron plastic beads
        M to 6 microns
22

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                                                                    Small Drinking Water Systems Handbook
Figure 6-12.  Dirty bag.


       Cartridge Filtration
       Cartridge filters are a technology suitable for remov-
       ing many microbes and reducing turbidity. These
       filters are easy to operate and maintain, making them
       suitable for treating low-turbidity water.  They can
       become fouled relatively quickly and must be
       replaced with new units.  Although these filter
       systems are operationally simple, they are not
       automated and can require relatively large operating
       budgets. A disinfectant may be recommended to
       prevent surface-fouling via microbial growth on the
       cartridge filters and to reduce microbial pass-through.
       Figure 6-13 shows a cartridge filter and housing.

       Cartridge filters are rigid cores (usually PVC) with
       surrounding deep-pleated filter media much like a
       Shop-Vac™ air filter. They are available in various
       pore sizes and materials depending on the intention of
       filtration and the source water quality.  The filter
       media are typically constructed of Polypropylene or
       Polyester but may be of other fibers for specific
       applications.  Pore sizes available may vary by
       vendor and material, but  are typically 100, 50, 25,  10,
       5, and 1 micron.  Cartridge filters may be disposable
       or washable depending on the material and vendor.
       Depending on the inlet water quality, flow rate, and
       filter pore size, a filter may last from one  hour to
       longer than a month.  If inlet water quality is poor, a
       pre-filtration step may be best to reduce filter changes
       and minimize cost. This can be achieved by using one
       cartridge filter system with a 50 or 25 micron filter for
       pre-filtration, followed by another cartridge filter
       system with a 5 or 1  micron filter for finer filtration.

       Cartridge filter housings  are generally made of
       stainless steel or fiberglass-reinforced-plastic for
       chemical resistance.  The housings may be equipped
       with one or two pressure gauges, drain ports, and an
                                                                Bag and Cartridge Filter Observations

                                                                Vendor support for systems can vary significantly
                                                                based on the experience of the representative
                                                                contacted. One vendor insisted on the use of a
                                                                special "installation" tool for proper bag filter
                                                                operation.  The special tool turned out to be a
                                                                baseball bat!

                                                                Seasonal variability in source water quality may
                                                                significantly impact the  life of the bag/cartridge
                                                                filter.  For surface water systems, influent turbidity
                                                                may increase dramatically following rain.
air release valve. The typical housing has a top-
placement lid, which  seals with an o-ring and is
clamped or bolted into place after a filter has been
inserted (Figure 6-13).

Inlet and outlet pressure gauges are used to determine
filter status. The pressure drop is measured and used
to indicate when the life of the filter has expired. It is
important to adhere to the manufacturer's recom-
mended pressure drops for replacement/cleaning to
prevent break-through and contamination of the
treated water.  Figure 6-14 shows dirty and clean
cartridge filters.

Cartridge filters can be "ganged", i.e., bundled
together, or set up in  various single configurations.
The units can be contained either singly in series or
parallel or ganged together in multiples within one

                                                             Figure 6-13. Cartridge filters and housings.
                                                                                                                   23

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       Small  Drinking Water Systems Handbook
       Figure 6-14. Dirty and clean cartridge filters.

       vessel. Like bag filters, cartridge filters can be
       designed for a variety of filtration applications. Most
       times the cartridge filter is used as a polishing filter
       following coarse sand filtration or bag treatment
       technologies. Again, like bag filters, one of the most
       cost-effective benefits of the cartridge filter is that it
       is commonly used without costly chemical additions,
       such as coagulation, flocculation, or filter-coated
       chemicals.  Like bag filtration technology, cartridge
       filters are designed  to capture protozoa,  parasites, or
       oocysts. These filters have "absolute" pore sizes
       designed and engineered into them that are reported
       to be uniform to contain and capture oocysts, protozo-
       ans, or parasites. At the same time, these filters permit
       bacteria, viruses, and fine colloids to pass through.

       Figure 6-15 shows a filter without internal structure
       failure. Figure 6-16  shows  the filter after water ham-
       mered the filter and caused the unit to collapse. These
       figures of the cartridge filter demonstrate that cartridge
       filters can be damaged under certain types of operation.

       EPA has evaluated several types of cartridge filters at
       the T&E Facility (see Table  6-5). Please note that the
       performance of the  filters varies widely with the inlet
       water flowrate, inlet turbidity and particle size.  A
       presentation of performance data that represents a full
       range of test conditions is  beyond the scope  of this
       document.  However, a summary of these evaluations
       is presented in Table 6-6.

       Membrane Filtration [13]
       Membranes act as selective barriers, allowing some
       contaminants to pass through the membrane while
       blocking the passage of others.  Membranes  may be
       made from a wide variety  of polymers consisting of
       several different materials for the substrate, the thin
       film, and other functional layers of the membranes.
       The thin film is typically made from materials like
Table 6-5. Cartridge Filter Characteristics
Cartridge
Filter
Cartridge 1
Cartridge 2
Cartridge 3
Pore
Size
1 micron
1 micron
2 micron
Construction
Vertical Pleated
Vertical Pleated
Compound Radial
Pleated
Surface
Area (sq. ft.)
30
40
117
    \
Figure 6-15. Normal cartridge filter.
A
Figure 6-16. Collapsed cartridge filter.

cellulose acetate that have tiny pores that allow the
passage of water while blocking bigger molecules.
The movement of material across a membrane
typically requires water pressure as the driving force.
There are four categories of pressure-driven mem-
brane processes:  microfiltration (MF), ultrafiltration
(UF), nanofiltration (NF), and reverse osmosis (RO).
24

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                                                            Small Drinking Water Systems  Handbook
Table 6-6. Cartridge Filtration Performance Summary
Filter System
Cartridge 1
Cartridge 2
Cartridge 3
Percent Reduction
Turbidity
50% - 80%
77% - 88%
70% - 89%
Particle Count
80% - 96%
89% - 96%

Membrane filters (such as MF and UF) act as sieves,
much like the bag and cartridge filters, just with smaller
pore sizes (0.003 to 0.5 microns). Other membrane
systems, NF and RO, actually block contaminants
dissolved in water down to the molecular level. RO and
NF processes are typically applied to remove dissolved
contaminants, including both inorganic and organic
compounds, and these processes operate at pressures
significantly higher (e.g., 800-1500 psi) than MF and
UF.  Low-pressure membrane processes (i.e., MF and
UF) are typically applied to remove paniculate and
microbial contaminants and can be operated under
positive or negative pressure (i.e., vacuum pressure).
Positive-pressure systems typically operate between 3
and 60 psi, whereas vacuum systems operate between -3
and -12 psi.  There is no significant difference between
the range of pressures at which MF and UF systems
operate. EPA has evaluated both MF and UF systems.
The performance summaries for both systems are
presented in Table 6-7.

Ultrafiltration
Ultrafiltration (UF) systems are effective for remov-
ing pathogens, while being affordable for small
systems.  Ultrafiltration is one of many processes
used to remove particles and microorganisms from
water. The Ultrafiltration technology  falls between
nanofiltration and microfiltration  on the filtration
spectrum. Systems may be designed to operate in a
single pass or in a recirculation mode.

UF systems are operated by pumping water through a
recirculation loop containing the membrane housing,
and through several membranes, which are usually
positioned in series.  The UF membranes are usually
large cartridges (EPA studied 8" x 40" cartridges) that
can range in pore size from 0.003 to 0.1 microns.  They
are usually constructed of plastic material.  These can be
hollow-fiber or spiral-wound membranes. The mem-
branes are also classified by pore diameter cut off
(PDCO), which is the diameter of the smallest particles it
retains, typically in the range of 0.1 to 10 microns. UF is
used for separating large macromolecules, such as
proteins and starches in other industry sectors.  Some-
times, UF membranes are classified by the molecular
weight cut off (MWCO) number.  MWCO is defined as
the molecular weight of the smallest molecule, 90% of
which is filtered by the membrane. The range of UF
systems typically spans between 10,000 to 500,000
MWCO.

When UF membranes begin to clog, a pressure drop
between the inlet and outlet will occur, along with a
reduction in flow rate. Adjustments should be made to
the raw inlet valve and reject water valve to maintain
flow as the membrane fouls. UF membranes must be
periodically backwashed according to their rated
pressure drops. It is important to follow manufacturer's
recommended pressure drops for backwashing and/or
manual cleaning to prevent permanent fouling, break-
through or pressure build-ups. Membranes are typically
cleaned with high concentrations of chlorine, acid, or
bases.  These are typically the only chemicals used for
these systems thus reducing operator attention from that
required for coagulation and flocculation.

EPA has conducted UF research studies at the T&E
Facility using a spiral wound membrane package plant.
The UF system had a nominal pore size of 0.005 mm
with a MWCO of 10,000. This package plant can treat
water at flow rates up to 15 gallons per minute (gpm).
Figure 6-17 depicts the UF system operated at the T&E
Facility. The results of these studies are included in
Table 6-8.

Studies were conducted to determine the efficiency of
the UF system to remove Cryptosporidium-sized
particles (4.5 micron plastic beads termed
"microspheres"). Initial testing showed an unacceptable
99.5% removal of the microspheres. However, there
was no indication from flow, pressure, or turbidity that
the spiral wound system was not properly removing the
microspheres.  Maintenance/inspection of the mem-
branes showed a crack in a plastic adaptor between the
membranes and the downstream end of the permeate
tube (see Figure 6-17[b]); this crack allowed raw water
to pass directly into the finished water. Figure 6-18
shows a photograph of the cracked adaptor. The
malfunctioning unit did not demonstrate any  problems
with pressure losses through the membrane due to the
Table 6-7. Membrane Filtration Performance Summary [15]
Filter System
MF System
UF System

Microspheres
99.95 - 99.99
99.3 - 99.998
Particle Count
99.985 -99.914
94 - 99.91
Cryptosporidium
99.957
99.95 - 99.994
MS2 Bacteriophages
NA

                                                                                                           25

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       Small  Drinking Water Systems Handbook
Table 6-8. Filtration Summary Table (as tested)
Technology
Bag Filter
Cartridge Filter
UF Membrane
Average
Cryptosporidium
Removal (%)
90.0
90 - 99.0
99.9 - 99.99
Filter Size
(microns)
1 +
0.5 +
0.005 - 1
Flow Rate
(gpm)a
Up to 40
up to 100
up to 30
Purchase
Price ($)
2,000
2,000
50,000
Filter Replace-
ment Cost ($)
50/bag
50-300/cartridge
5,000/element
Expected Filter Life
Hours/days/weeks
Hours/days/ weeks
Up to 3 years
        agpm = Gallons per minute
       Figure 6-17.
       (a) UF System
       (b) UF System Cartridges in Series
       (c) UF System Cartridge Cut-Out
       cracked adaptor and showed acceptable turbidity
       removal results. Small system operators should be
       aware that EPA has also observed and identified this
       situation in the field. Each observance was related to
       improperly installed UF filters, broken o-rings, or
       (cracked) adaptors. After each of the units was repaired,
       results indicated up to 99.998% removal of
       microspheres using the UF treatment package plant.
       Cryptosporidium sp. was also injected into the feed
       supply water to the UF package plant.  Under laboratory
       conditions, the UF plant achieved a removal of 99.95%
       to 99.994%. A test was conducted using bacillus spores
       to simulate cyptosporidium removal. These tests
       showed removals similar to that obtained in the tests
       using Cryptosporidium (about 99.99%).

       Twenty-four studies were performed at an average inlet
       pressure of 29 psi; the effluent flow rate averaged 7.2
       gpm. The sample collection  duration of each test ranged
       from 218 to 5,532 minutes with an average of 1,110
       minutes.  The  system was operated continuously and
       was purged with tap water at least 8 hours between each
       test run. Results indicated a 99.9% to 99.99% removal
       range of microspheres from the influent to the permeate,
with an overall removal average of 99.5% (Figure 6-19).
As a comparison, Cryptosporidium filtration achieved a
removal of 99.5% oocysts, which was very similar to the
average log removal of the 4.5 microns standardized
plastic test beads.

However, the last data point in Figure 6-19 is shown in
detail in Figure 6-20. This data point represents samples
Figure 6- 7 8.  Cracked plastic adaptor used
between membranes.
26

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  b.uu

  5.00
B 4'00
g
| 3.00

S1
J 2.00
  1.00
  0.00
     0        5000       10000      15000      2000C
                       Tima /min\
      Figure 6-19.  Log removal of beads vs. membrane
      run-time.
100000

100000

 10000

 1000

  100

  10

   1

   0
iiiin
        1328     2846     4174    4870    5234     5532
                        Time (min.)
      Figure 6-20.  Number of Beads in Effluent vs Run
      Time
      being taken from the permeate over almost four days
      compared to just one day for the other data points shown
      in Figure 6-19. After 5,532 minutes (approximately
      3.84 days) of run time, plastic test beads were still found
      in the permeate even though influent spiking had
      occurred over a two-hour period at the beginning of the
      experiment four days earlier. Removal was 99.5% for
      the individual experiment, lower than most of the
      previous experiments. The higher removal rate achieved
      by the shorter experiments could be the effect of
      insufficient sample collection time, and suggests that
      particles may have long residence times in membrane
      filters but are still capable of ultimately passing through.

      Tests were also conducted to evaluate the effectiveness
      of the UF system in removing a virus. MS2 bacterioph-
      age was used in the experimental runs to simulate a
      particle similar in size to a virus. The test conditions
      were similar to the conditions used for the
      cryptosporidum  tests. There were no MS2 bacterioph-
      ages detected in the permeate from the UF. However,
      this is a likely result of the sampling technique used
      since the permeate could be examined in discrete
      intervals only because of the small size of the MS2
      bacteriophage. (In the cryptosporidum study, a portion
      of the permeate was constantly filtered to catch any
      particles. In this study, this was not possible because a
      filter to catch the MS2 bateriophages is not available).
                                                        Small Drinking Water Systems Handbook
                                               It should be noted that although Cryptosporidium is
                                               4-6 microns in size, it can still pass through an
                                               absolute 3-micron size filter by deforming and
                                               squeezing through. The pliability of Cryptosporidium
                                               is demonstrated in Figures 6-21 (a) and (b).

Figure 6-21 a. Cryptosporidium oocyst on upper surface of
3 micron pore.
    •2 5 k V   X r j 5 0 8
        ^•1
figure 6-276.  Cryptosporidium oocyst coming
3 micron pore.
                                                                                0113-04

                                                                                through
                                            Figure 6-22. Micro Filtration System.
                                                                                               27

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       Small Drinking Water Systems Handbook
   United States  Forest Service—Hybrid Filtration/
   Disinfection System (see Figure 6-24)

   A hybrid filtration/disinfection system was commis-
   sioned by the United States Forest Service San Dimas
   Technology and Development Center in Los Angeles,
   California, as a follow up to EPA's bag filtration and on-
   site chlorine generation studies.  This system incorpo-
   rated bag or cartridge filters prior to an on-site chlorine
   generator onto a skid specially designed for intermittent
   operation at campgrounds.  The skid was designed to fit
   into the bed of a pickup truck capable of being lifted
   and installed manually (four people) at the campground.
   An ion-exchange softener was included on the skid to
   produce brine-free water to maintain pump operation.
   The system was also designed for remote monitoring
   and control, and solar power with battery backup.
   Based on the campground needs, it was determined that
   cartridge filtration was preferable and more economical
   because of the low turbidity in the raw mountain water
   and the desire for a better Cryptosporidium and Giardia
   barrier.

   In-house research at the San Dimas facility concluded
   that the cartridge filters can achieve 99% (2 Log)
   removal of Giardia-sized particles (5- to 15-micron
   size) in low-turbidity (<0.60 NTU) raw waters.  Inter-
   mittent operation did not appear to cause any additional
   problems, nor did there appear to be any loss in removal
   efficiencies immediately after the system was turned
   off. The removals were achieved 95% of the time, and
   the system was able to function beyond the 20-psi
   differential pressure between raw and finished sampling
   points (that determines cartridge life). The cartridge
   filters were able to handle short-term spikes, although
   algae blooms in raw water resulted in short filter life
   and early filter failure.  Particle-counting instruments
   also proved problematic.

       Thus, it is assumed that the UF system effectiveness in
       removing MS2 bacteriophages is similar to that
       observed during the cryptosporidiiim study, or about a
       99.99% removal.

       Microfiltration
       Various field evaluations have been conducted to
       assess the operational performance of  microfiltration
       technology and provide information  about the
       removal of physical and biological contaminants
       under continuous operation.  Figure 6-22 shows a
       typical MF unit.  Microfiltration membranes nor-
       mally have pore sizes 0.1  microns or greater [16].
       The water flow of the test system ranged between 15
       and 34 gpm.  Standardized plastic test  beads of 4.5
       microns were injected into the raw untreated test
       water. The reduction of turbidity was 93.33% and the
       reduction of Cryptosporidium was 99.957%. Particle
       counts were performed resulting in removals of
       99.985% for particles in the 4-6 micron range and
  In anticipation of small system needs in meeting the
  Stage 1 Disinfectants/Disinfection Byproducts Rule, the
  Ground Water Rule, and the Stage 1 Enhanced Surface
  Water Treatment Rule, the WSWRD has investigated
  alternative technologies focusing on their ability to
  inactivate Cryptosporidium while at the same time
  being affordable and easy to operate and maintain.

99.914% for particles in the 1-25 micron range.  Thus,
even though the plastic test beads have a diameter of
4.5 microns, beads are seen to pass through the
membrane (or through seals, adapters,  or gaskets) even
within the 1 to 4 micron range. Collectively, results
showed no influence due to the different flow rates.
The results indicate that microfiltration technology is a
feasible small system drinking  water treatment technol-
ogy for particle removal [13].

Note that the final turbidity achieved by a UF system
was <0.2 NTU regardless of the influent turbidity. Thus
percent removal does not provide a meaningful measure
of UF performance for turbidity. This is not, however,
true for MF systems where the effluent turbidity is
dependent on the influent turbidity. The MF systems
tested at T&E achieved removals of 90% to 98% with
finished turbidity levels ranging between 0.1 to 0.6 microns.
A real-world case study and example of a UF System
package plant is included in Section  9 of this document.

Filtration Summary
As discussed previously in this section, EPA has
evaluated several types of filtration systems at the T&E
Facility and various field locations. The operating
conditions, microbe  (Cryptosporidium)  removal
efficiency, initial and operating cost for the individual
units vary widely. Table 6-8 presents a summary of
information for each type of filter.

Based upon the above technology investigations, it
appears that there are several alternative filtration
technologies. Depending on raw water characteris-
tics, a likely configuration can consist of filters in
series with decreasingly small pore  sizes that can, in
effect, remove most microbiological contaminants,
reducing the need for chemical coagulants and
disinfectants. Operation  and  maintenance would be
simplified, thus enhancing long-term compliance.

Disinfection
Disinfection is the process used to reduce the number of
pathogenic microbes in water.  The Surface Water
Treatment Rule (SWTR) [18] requires PWSs to disinfect
water obtained from surface water supplies or ground
water sources under the influence of surface water. The
proposed Ground Water Rule may require PWSs to
disinfect their well water supplies. MCL and M/R
violations of the SDWA and its amendments over the
28

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  Several guidance manuals are available to help PWS
  operators comply with the Stage 1 Disinfectants/
  Disinfection Byproducts Rule. Examples of such
  guidance manuals include:

  •   Disinfection Profiling and Benchmarking
       Guidance Manual (EPA 815-R-99-013), August
       1999.

  •   Alternative Disinfectants and Oxidants Guidance
       Manual (EPA 815-R-99-014), April 1999.

  •   Microbial and Disinfection Byproduct Rules
       Simultaneous Compliance Guidance Manual
       (EPA 815-R-99-015), August 1999.

      years show that small systems are either (1) unable to
      simply disinfect their water or (2) record and submit their
      data to the appropriate oversight agency.  Typically,
      some form of chlorine is used as a disinfectant. More
      recently, ultra-violet (UV) radiation, Ozonation (O3) or a
      combination of UV/O3 technologies are being used for
      disinfection.

      The use of chlorine as a disinfectant is commonly
      accepted worldwide. Chlorination is a popular choice
      because of its residual disinfection characteristics. Its
      effectiveness is very simple to test; one need only
      measure the residual chlorine at the point of consump-
      tion to ensure proper disinfection. Test procedures for
      measuring chlorine are presented later in this section.

      However, people are becoming more concerned about
      the disinfection by-products (DBPs) of chlorine and are
      looking for alternatives. Chlorine reduces  bacteria, but
      it also reacts with other organic impurities  present in
      water producing various trihalomethanes (THMs) which
      are listed as probable or possible human carcinogens
      (cancer-causing agents). Other disadvantages of
      chlorination are undesirable tastes and odors, require-
      ment of additional equipment (such as tanks) to
      guarantee proper contact time, and extra time to monitor
      and ensure proper residual concentration level. It also
       Small Drinking Water Systems  Handbook


performs poorly in removing viruses (such as enterovirus
and hepatitis A) and protozoa (such as Cryptosporidia
and Giardia).

Ozonation is another disinfection method. Ozone is
effective as an oxidizing agent in removing bacteria with
a relatively short exposure time. Ozone generators are
used to produce ozone gas on site, since the gas is
unstable and has a very short life. These generators must
be installed and monitored cautiously, because high
concentration levels of ozone will oxidize and deterio-
rate all downstream piping and components. With home
ozone systems, leftover ozone must be removed with an
off-gas tank to ensure homeowners are not exposed to
ozone gas, which is a strong irritant. High levels of
ozone are extremely harmful especially in enclosed or
low-ventilation areas. Ozone also forms highly carcino-
genic DBPs with bromide to form bromate, broform,
dibromeacetic acid, and others. Thus, there is no "silver
bullet" for disinfection that does not have some draw-
backs.  In PWSs, UV equipment or biological filters are
typically installed to remove ozone residuals prior to
filtration.

On site ozone generating equipment is costly compared
to other disinfection technologies. The effectiveness of
the forms of chlorine and ozone in killing micro-
organisms (i.e., biocidal efficiency) varies with the type
of micro-organism and  the water quality conditions
(such as pH). The relative effectiveness of chlorine and
ozone in killing microbes and the stability of each
disinfectant is summarized in Table 6-9.

The use of UV light as means of water disinfection has
been a proven process for many years. The benefit of the
UV disinfection process is that  it does not use any
chemicals and appears to be effective for Cryptosporidium.
However, residual disinfection (to account for contami-
nation via the distribution system) is not possible.

Operators need to use  the optimum amount of
disinfecting agent to achieve appropriate disinfection
and minimize DBP formation.  Currently, the regu-
Table 6-9. Summary of Disinfectant Characteristics Relating to Biocidal Efficiency [19]
Disinfectant
Ozone
Chlorine dioxide13
Free chlorine13
Rank3
Biocidal Efficiency
1
2
3
Stability
4
2
3
pH Effects on Efficiency
(pH ranges 6-9)
Little effect
pH increase is beneficial
pH increase is detrimental
a 1  = best, 4 = worst.
13 Ranking influenced by pH.
                                                                                                                  29

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       Small Drinking Water Systems Handbook
       lated DBFs in the United States are trihalomethanes
       (THMs) with a maximum contaminant level of 80 parts
       per billion (ppb).  However, the practice of chlorination
       for pre-oxidation or for disinfection can result in the
       formation of chlorinated organic by-products.  The
       recently promulgated Disinfectant/Disinfection
       Byproducts (D/DBP) Rule will result in the regulation
       of several other by-products of chlorination, such as
       haloacetic acids (HAAS) (to 0.060 mg/L), along  with a
       potential reduction in the current THM standard  of 80
       ppb (Federal Register, 1998). In some cases this might
       result in a change to an alternative pre-oxidant, or
       disinfectant, use of membranes, or elimination of the
       use of free chlorine [9]. To minimize the formation of
       DBFs, under the SWTR [18] and the proposed Enhanced
       Surface Water Treatment Rule (ESWTR) [20] most
       utilities are also required to filter their water unless the
       following conditions are met in the surface water prior
       to disinfection:
       •    fecal coliform bacteria <20/100 milliliters (mL)
           in 90% of samples,
           total coliform bacteria <100/100 mL in 90% of
           samples,
           turbidity <5 NTU, and
       •    other MCLs met.

       Treatment plants exempt from filtration must disinfect
       to achieve 99.99% inactivation of viruses, and 99.9%
       inactivation of Giardia lamblia cysts. For systems that
       use chlorine for disinfection, compliance with these
       requirements must be demonstrated with the CT
       approach (the product of the average disinfectant
       concentration and contact time). CT values estimated
       for actual disinfection systems must be equal to or
       greater than those published in the SWTR Guidance
       Manual for viruses and G. Lamblia cysts respectively [9].
             For a List of CT Values, go to:
  www.epa.gov/safewater/mdbp/pdf/profile/benchpt4.pdf
       Also, EPA studies have demonstrated that the pliabil-
       ity of Cryptosporidium oocysts may permit the
       oocysts to pass through a filtration system, thus
       making disinfection that much more important as a
       barrier [17]. Just like large systems,  small systems
       have to be even more concerned with the safety and
       ease of handling, shipping, storage, and the capital,
       and operation and maintenance (O&M) costs associ-
       ated with the use of appropriate disinfectant technology.

       EPA has evaluated several disinfection technologies
       that are affordable and easy to use from a small
       systems perspective.  An evaluation summary of these
       technologies is presented in the following subsec-
       tions.
Chlorine Residual and Monitoring [9]
As identified earlier, chlorination is preferred for
disinfection at small treatment plants and for small
utilities.  The following four methods are popularly
used to monitor residual (free and total) chlorine in
treated water supplies:

1.  N,N-diethyl-p-phenylenediamine (DPD)
    colorimetric method

2.  lodometric method,

3.  Polarographic membrane sensors, and

4.  Amperometric Electrodes

The DPD colorimetric method is most commonly used
and is based on the American Society for Testing and
Materials (ASTM) Standard Method. In this method,
DPD is oxidized by chlorine to form two oxidation
products with one product being darker in color than
the other. The color intensity is measured by either a
colorimeter (color  wheel) or spectrophotometer and
corresponds to the amount of free and total chlorine
present in the sample.  This method can measure both
free and total chlorine.

The lodometric method involves adding potassium
iodide  to a water sample to react with the available
chlorine to form iodine. The amount of free iodine
generated is monitored and correlated to the amount
of chlorine present.  Since this method does not
distinguish between free and combined chlorine, it
should only be used when monitoring for total
chlorine.

The Polarographic Membrane sensor method consists
of a pair of electrodes that monitor free chlorine. The
electrodes are immersed in a conductive electrolyte
and isolated from the sample by a chlorine-permeable
membrane.  Free chlorine diffuses through the
membrane and is reduced to chloride on the surface of
the electrodes, generating a flow of electrons between
the two electrodes.  The current generated is propor-
tional to the concentration of the free chlorine.

Amperometric Electrodes method consist of two
combination probes that use a platinum cathode and a
silver anode to amperometrically measure free chlorine
along with pH and temperature. Within these elec-
trodes, an electrochemical reaction occurs based on
the available chlorine concentration, generating a
proportional current. This method can measure free
chlorine.

EPA found the cost of the various sensors to range
from $400 to over  $10,000 for stand-alone,  sophisti-
cated sensors that were automated and combined
multiple monitoring parameters. A standard, online,
process control instrument with sampling assembly
and analyzer ranged in cost from $2,000 and $10,000.
30

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                                                                Small  Drinking Water Systems Handbook
    Disinfection by Chlorination
    Chlorine is generally obtained for disinfection in the
    form of gaseous chlorine, onsite chlorine dioxide
    generators, solid calcium hypochlorite tablets, or
    liquid sodium hypochlorite (bleach).  Gaseous
    chlorine and onsite chlorine dioxide generators are
    typically found at larger drinking water systems.
    Small drinking water systems sometimes use solid
    calcium hypochlorite, which is  typically sold as a dry
    solid or in the form of tablets for use in proprietary
    dispensers.  This method of disinfection is, however,
    expensive, suitable mainly for low flow applications,
    and the use of calcium can lead to scale formation.
    For the most part, small system operators continue to
    disinfect water using common household liquid
    bleach or swimming pool chlorine.

    There are, however, other chlorination processes
    available that small system operators should consider.
    One such alternative that has been evaluated exten-
    sively by EPA's WSWRD is the on-site salt brine
    electrolysis chlorine generator system. The salt brine
    solution together with the electrolytic cell generates a
    solution (liquor) of primarily sodium  hypochlorous
    (chlorine) acid.  Operators should be aware that some
    vendors claim that their electrolytic generator
    enhances pathogen (Cryptosporidium  sp.  and Giardia
    sp.) inactivation by using the combined actions of
    various mixed oxidant reactions generated from the
    electrolytic cell. The further claim is  that this mix of
    oxidants minimizes DBF formation.  However, EPA
    has not been able to demonstrate the presence of any
    other oxidant (other than sodium hypochlorous acid)
    generated from these units.

    Electrolysis of salt brine to produce hypochlorite has
On-site salt-brine electrolysis chlorine generator
systems can be very attractive to small operators,
because they are generally safer to handle and operate
than chlorine gas or liquid (sodium hypochlorite or
calcium hypochlorite) systems.  EPA conducted studies
to evaluate three different on-site salt brine based
chlorine generators and compared them to each other
and to liquid bleach.  EPA noted a wide variation in
prices when purchasing these units. The prices for the
three salt-brine generators designed specifically for
small systems cost in the range of $18,000 to $35,000
(depending on the manufacturer).  Since most small
treatment system operators and facilities have a limited
budget, EPA decided to evaluate other avenues and
options for the small system operator.  As a fourth
system, EPA purchased a salt-brine generator from a
swimming pool supply company for $750 and added
plumbing, pump, pressure gauge, flow control and
brine tank for  $525 for a total equipment cost of
$1,275! (Figure 6-23)
    Breakpoint Chlorination [9]
    Small treatment operators should remember that
    ground water, primarily in rural areas, tends to be
    seasonally contaminated with ammonia nitrogen
    from sources that may include crop fertilizers.
    Because of this, they must achieve a stable residual
    of stronger disinfectant-free chlorine. In other
    words, the formation of chloramines must be
    avoided by practicing "breakpoint chlorination."
    Breakpoint chlorination is the process in which
    chlorine is added at levels that result in the oxida-
    tion (removal) of ammonia nitrogen.  This happens
    by converting the ammonia-nitrogen to nitrogen
    gas in the presence of chlorine. The rate of
    breakpoint chlorination is fastest at pH levels in the
    range of 7 to 8, and tends to slow-down below and
    above the optimum pH range.  Thus monitoring and
    controlling the pH is critical for optimization.
been practiced for nearly a century and was the early
method for industrial preparation of the chemical.
The basic operating principle involves electrolyzing a
concentrated brine solution which generates chlorine
at the anode and hydrogen together with sodium
hydroxide at the cathode. The hydrogen is allowed to
vent whereas the chlorine is allowed to remain in
contact with the electrolyte thus forming sodium
hypochlorite. Basically, the formation of sodium
hypochlorite occurs as follows:

Salt + Water + Energy => Sodium Hypochlorite +
Hydrogen Gas

When selecting an electrolytic chlorine generator,
operators should be aware that the performance of
each unit may be significantly affected by the quality
of the salt. Each vendor will recommend the type of
salt to be used in its unit. It is important to note that
all salt is not the same. Bromide levels in the salt can
significantly affect the level of bromate found in the
treated (chlorinated) water.  Although  safer than
conventional chlorine gas treatment, safety can also
be an issue with the chlorine salt brine generators. As
identified above, hydrogen gas is generated, and
although it is in very small amounts and for the most
part not considered hazardous, any collection of
hydrogen gas can be a potential for explosion or fire.
Thus, each electrolytic chlorine generating unit, or
the building in which it is set up, should have some
type of ventilation system to assure hydrogen gas
does not collect. It must be noted that the salt brine
electrolysis-based generators are generally safer to
handle and operate than conventional liquid or solid
sodium hypochlorite, calcium hypochlorite, or
chlorine gas systems.
                                                                                                              31

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       Small Drinking Water Systems Handbook
      Each utility or operator should evaluate the volume
      and quality of salt being used to generate the required
      amount of chlorine.  Replacement parts and life for
      items, such as electrolytic cell, static mixers, power
      supplies and tubing and connectors, should be
      considered. The operator should note that EPA has
      demonstrated that drinking water disinfectants, such
      as chlorine or monochloramine, at typical dosages
      have virtually no effect on the inactivation of
      Cryptosporidium oocysts. [21]

      EPA conducted studies to evaluate three different on-
      site salt brine-based chlorine generators and com-
      pared them to each other and to liquid bleach (see
      insert). Each unit was capable of generating sodium
      hypochlorite on an as-needed basis by electrolyzing
      salt water. Figures 6-23 through 6-25 show pictures
      of the four on site chlorine generators evaluated.

      Performance Evaluation of Various
      Disinfection Technologies
      For the on-site chlorine generators, the performance
      can be evaluated based on the amount of chlorine
      generated. The overall performance of the disinfec-
      tion system is based on the removal efficiency of
      microbial organisms, such as Total Coliforms, Fecal
      Coliforms, E. Coli, Cryptosporidium, etc.  EPA
      evaluated the performance of disinfection systems by
      operating these systems under various "test" conditions.

      Disinfection Summary
      Each of the three chlorine generators evaluated
      showed high concentrations (as much as 400 mg/L)
      of free chlorine to be generated.  A wide variety of
      analytical methods were used to evaluate the disinfec-
      tant generation at the actual anode and cathode cells.
      Based on the analytical results, EPA concluded that
      only free chlorine was produced [22]. EPA studies
      involving Cryptosporidium oocysts also  did not show
      any enhanced disinfection from using the electro-
      lyzed salt-brine "chlorine" solutions when compared
      to liquid bleach "chlorine." Cryptosporidium removal
      efficiencies were less than 90%.

      Ultraviolet (UV)/Ozone (O3)
      EPA evaluated a packaged UV/O3 (also referred to as
      Advanced Oxidation Process or AOP) system for
      inactivating microorganisms. The unit evaluated was
      capable of processing up to 10 gpm of water and is
      engineered to  ensure adequate UV intensity and
      ozone residuals for advanced oxidation processes.
      The UV/O3 system has a custom-built ozone genera-
      tion, injection and contacting system. The combined
      system consists of a  13 gallon (49 liter) contact tank,
      a 5 gram/hour ozone generator with air dryer, and a
      cylindrical low-pressure 254 nm UV lamp reactor, and
      a recirculation pump. The use of purity components,
Figure 6-23. On-Site Chlorine Generator #1.
Figure 6-24. On-Site Chlorine Generator #2.
Figure 6-25. On-Site Chlorine Generator #3.
32

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                                                                  Small Drinking Water Systems Handbook
 Disinfection System Observations:
 Research on on-site chlorine generators and UV/O3
 treatment technologies have resulted in the following
 observations:

 The disinfection capabilities of disinfection systems
 are a function of dosage and contact time.  For the on-
 site chlorine generators, the chlorine dosage and free
 residual chlorine are critical performance parameters.
 For UV/O3 treatment technologies, the UV intensity
 and ozone dosage are critical performance parameters.
 For both technologies, a reaction chamber or a contact
 tank provides a mixing "area" for the disinfecting
 agent(s) and microorganisms  in the water.

 On-site chlorine generators are designed to convert salt
 to chlorine via an electrolytic cell. As a result, the
 hazards  associated with handling liquid chlorine are
 not a concern.  Salt is added to the chlorine generator
 or contact tank in bulk and requires lifting by the
 operator. Brine concentration levels are critical for
 proper operation of on-site chlorine generators. The
 accumulation of salt residue requires maintenance of
 system tanks and piping.

 UV/O3 systems oxidize organics instantly.  Ozone
 reacts quickly without leaving a residual disinfectant.
 UV disinfection depends upon the intensity of the light
 contacting the water. As a result,  waters with low
 turbidity and color are preferred for UV treatment.
 Providing  stable ozone dosage and UV intensity are
 critical for providing consistent disinfection.

 Several things can be done to improve UV/O3 system
 performance. Air dryer dessicant  can be replaced on a
 regular basis to improve ozone generation. Ozone
 dosage can be improved by increasing the  air flow into
 the ozone generator and optimizing the vacuum at the
 venturi injector.  For optimal  performance, the UV/O3
 system should be operated as specified by  the manu-
 facturer. Alternatively, an oxygen generator can be
 used to feed the ozone generator; this can be, however,
 an expensive option.
such as a natural kynar venturi injector, a stainless steel
UV light housing, stainless steel recirculation loop
piping, and a rust proof extruded aluminum frame are
also features of this system. The total volume of the
UV/O3 system is 15 gallons (57 liters).

The combined UV/O3 system by far achieved the
highest disinfection rates for bacterial contamination.
The UV/O3 disinfection technology is useful in removing
other organic contaminants, such as MTBE, perchloroet-
hylene, and trichloroethylene.  Table 6-10 provides a
summary of the UV/O3 disinfection study evaluations.

As discussed before, EPA evaluated several types of
disinfection systems at the T&E Facility and various
field locations. The operating conditions, microbe
removal efficiency, and initial and operating cost for the
individual units vary widely. Table 6-9 presents a
summary of information for each type of disinfection
system.  Note that the flow rates and the chlorine
generation rates, replacement part(s) cost(s), and
replacement frequency varies widely depending upon
the  generator unit. The chlorine generation rate depends
upon the electrolytic cell size and the direct current
(DC) capacity of the system. Typically, the parts that
need to be replaced on an annual basis (depending upon
use) include: feed pump(s), electrolytic cell, and filters.
The replacement costs range between $100-$1,000
depending on the unit and the replacement part.

Advanced Oxidation Process  for Disinfection &
Destruction
Advanced oxidation processes (AOP) use oxidants  to
destroy  organic contamination in drinking water.
Several  different oxidants, such as ozone, hydrogen
peroxide, and hydroxyl radicals, may be used. EPA
evaluated the use of an AOP system comprised of
UV/O3 for disinfection potential and MTBE destruc-
tion. This effort was intended to investigate if an
AOP system can be used to disinfect the water, and at
the  same time destroy organic compounds.

AOP Using UV/Ozonation for MTBE  Removal
Methyl-tert-Butyl-Ether (MTBE)  is a gasoline
additive that has been found in drinking water. UV
irradiation and ozonation are  known  to effectively
destroy  organic compounds in drinking water and
Table 6-10. Disinfection Summary Table (as tested)
Technology
Chlorine Generators
UV
Ozone
UV/Ozone
Cryptosporidium Removal

99 - 99.9%
99 - 99.9%
99.9 - 99.99%
Flow Rate (gpm)a
varies
12

12
Purchase Price
$800 - 20,00i
$2,000

$7,000
agpm = Gallons per minute
                                                                                                                33

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      Small Drinking Water Systems Handbook
   Chlorine exists in water in various forms.  These
   forms include free and combined chlorine and are
   measures of the residual chlorine in the water supply.
   [23]

   Free Chlorine: Chlorine that is applied to water in its
   liquid or gas form (hypochlorite) undergoes hydroly-
   sis (chlorine mixed with water) to form free (avail-
   able) chlorine. This free chlorine is in the form of
   aqueous molecular chlorine,  hypochlorous acid, and
   hypochlorite ion.  The proportions of these free
   chlorine forms are dependent on pH  and temperature.
   At the normal pH of most waters hypochlorous acid
   and hypochlorite ion will predominate the solution.

   Combined Chlorine: Free chlorine reacts easily with
   ammonia and certain nitrogenous compounds to form
   combined chlorine.  Chlorine reacts with the ammonia
   it forms chloramines.  The chloramines are
   monochloramine, dichloramine, and nitrogen trichlo-
   ride as well as some other chloro-derivatives.  The
   presence and concentrations  of these combined forms
   depend on pH, temperature, initial chlorine-to-
   nitrogen ratio, absolute chlorine demand, and reaction
   time.  Note that both free and combined chlorine
   maybe present at the same time and, historically, the
   principal analytical problem  has been to distinguish
   between free and combined forms of chlorine.
   Combined chlorine is determined by running free
   chlorine and total chlorine tests and then subtracting
   the free chlorine result from  the total chlorine result.

   Residual Chlorine: Residual chlorine is the amount
   of chlorine remaining in the water after a specified
   contact period.
                     1       10      20       30
                          Tllnr (rtnulel)

                      • UV      * Ozone       » OzonaUV
Figure 6-26. Package AOP Plant MTBE Removal vs Time,
        Batch Test Run
Figure 6-27. Package AOP Plant Formation of t-BF vs Time
Injecting 30 [ig/L MTBE.
      other matrices.  Thus, in addition to treatment for
      Cryptosporidium, UV/O3 systems have also demon-
      strated the ability to treat MTBE in drinking water.
      EPA has evaluated the removal of MTBE at influent
      concentrations of 30  and 75 micrograms per liter (jag/
      L) in a water supply. Ultraviolet light treatment alone
      effected negligible MTBE removal. O3 alone was
      capable of removing  >80% of the MTBE after 60
      minutes, but removal efficiency depended strongly on
      the reaction time and on the initial MTBE concentra-
      tion.  The combined UV/O3 process showed the best
      potential for MTBE removal.  Complete MTBE
      removal was observed within 20 minutes reaction
      time. Several by-products are generated as a result of
      MTBE treatment.  These by-products include f-butyl
      alcohol (TEA), f-butyl formate (TBF), formaldehyde,
      isopropyl alcohol, acetone, and acetic acid methyl
      ester. [24] [25]  Figures 6-26 and 6-27 demonstrate
      the formation of byproducts and removal of MTBE in
      the AOP process.
34

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                                                         Small  Drinking Water Systems Handbook
7.0  Point-of-Use/Point-of-Entry Applications
Public water supply consumers may not always
possess the financial resources, technical ability, or
physical space to own and operate custom-built
treatment plants. Small drinking water treatment
systems, such as Point-Of-Use and Point-Of-Entry
(POU/POE) units, may be the best solution for
providing safe drinking water to individual homes,
businesses, apartment buildings, and even small
towns. These small system alternatives can be used
for not only treating some raw water problems, but
they are excellent for treating finished water that may
have degraded in distribution or storage or to ensure that
susceptible consumers, such as the very young, very old,
or immuno-compromised, receive safe drinking water.
 For additional  information, please see:
        www.nsf. org/water. html
             www.wqa.org
          www.ndwc.wvu.edu
As discussed in Section 6, the 1996 SDWA Amend-
ments identified two classes of technologies for Small
Systems: (1) compliance technologies and (2)
variance technologies. //1] A "compliance technol-
ogy" may refer to a technology or any other technique
that is affordable by a small system that achieves
compliance with the MCL.  These could include POU/
POE systems. "Variance technologies" are only
approved for those system sizes/source water quality
combinations when there is no available "compliance
technology." So, if there is  a "compliance technol-
ogy" listed for your system, other "variance technolo-
gies" will not be allowed. While "variance technolo-
gies" might not reach the MCLs, they must achieve
the maximum removal or inactivation efficiency
affordable considering the size of your system and the
water quality of the source water.  Public health must
be protected.

The 1996 SDWA require that the MCLs be set  as
close as possible  to the MCLGs as is "feasible."
Feasible meant that the best technology or treatment
technique had to be determined based upon field
conditions, taking cost into  account.  The technolo-
gies that meet this criterion are called "Best Available
Technology" (BAT). [10] Major concerns  regarding
the use of POU/POE technology  are:

    the problem of monitoring treatment
    performance so that it  is comparable to central
    treatment;

    POU devices only treat water at an individual tap
    (usually the kitchen faucet) and therefore  raise
    the possibility of potential exposure at other
    faucets. Also, they do not treat contaminants
    introduced by the shower (breathing) and skin
    contact (bathing). Thus, POU/POE devices are
    not designated as BAT;

    these devices are generally not affordable by
    large metropolitan water systems.

POU devices are only considered acceptable for use
as interim measures, such as a condition of obtaining
a variance or exemption to  avoid unreasonable risks
to health before full compliance can be achieved. [26]

POE systems could be used if:

a.  The device is kept in working order. The PWS is
    responsible for operating and maintaining all
    parts  of the treatment system although central
    ownership is not necessary.

b.  An effective monitoring plan must be developed
    and approved by the state before POE devices
    are installed.  A unique monitoring plan must be
    installed that ensures that the POE device
    provides health  protection equivalent to central
    water treatment.

c.  Because there are no generally accepted
    standards for design and construction of POE
    devices, and there are a variety of designs
    available, the state may require adequate
    certification of performance testing and field
    testing. A rigorous engineering design and
    review of each type of device is required.  Either
    the State, or a third party acceptable to the State,
    can conduct a certification program.

d.  A key factor in applying POE treatment is
    maintaining the microbiological safety of treated
    water. There is  a tendency for POE devices to
    increase bacterial concentrations in treated
    water. This is a particular problem for activated
    carbon technologies. Therefore, it may be
    necessary to use frequent back-washing,
    post-filter disinfection, and monitoring to ensure
    the microbiological safety of the treated water.
    The EPA considers this a necessary condition
    because disinfection is not normally provided
    after POE treatment, while it is commonly used
    in central treatment.

e.  The EPA requires that  every building connected
    to a PWS have a POE  device that is installed,
    maintained, and adequately monitored.  The
    rights and responsibilities of the utility customer
    must be transferred to  the new owner with the
                                                                                                     35

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      Small Drinking Water Systems Handbook
           title when the building is sold (Federal Register,
           1987).

      In 1996, things changed. POU/POE could now be
      considered a "Final Solution." The 1996 regulations
      required the POU/POE units to be "owned, con-
      trolled,  and maintained by the PWS or by a person
      under contract with the PWS operator to ensure
      proper operation and maintenance and compliance
      with the MCLs or treatment technique and equipped
      with mechanical warnings to ensure that customers
      are automatically notified of operational problems"
      [10]. Under this  rule, POE devices are considered an
      acceptable means of compliance because POE can
      provide water that meets MCLs at all points in  the
      home.  It is also possible that POE devices may be
      cost effective for small systems or NTNCWS.  In
      many cases, these devices are essentially the same as
      central treatment. In 1998, POU devices were listed
      as "compliance technologies" for inorganics, syn-
      thetic organic chemicals, and radionuclides, but not
      for volatile organic chemicals (VOCs).

      POU/POE Treatment
      Currently, POU/POE treatment is used to control a
      wide variety of contaminants in drinking water.
      When evaluating various POU/POE treatment
      systems, six major factors need to be considered in
      the decision process.  These factors are:

      1.   quality and type of water source,

      2.   type and extent of contamination,

      3.   cost of water,

      4.   treatment requirements,

      5.   waste disposal requirements,

      6.   state-approved operation and maintenance plan.

      Basically, the same technology used in treatment
      plants for community water systems can be used in
      POU/POE treatment. POU/POE treatment is applied
      to reduce levels of organic contaminants, turbidity,
      fluoride, iron, radium, chlorine, arsenic, nitrate,
      ammonia, microorganisms including cysts, and many
      other contaminants.  Aesthetic parameters, such as
      taste, odor, or color, can also be improved with POU/
      POE treatment [26]. Table 7-1 summarizes key
      features of commonly used POU/POE technologies.
      Figure 7-1 shows a typical POU (under a kitchen
      sink) RO Unit.

      POU/POE Cost
      The cost and application of POU/POE as a final
      solution for a small system or portion of a larger
      system is highly  dependent upon the situation.  Table
7-2 summarizes relative costs associated with various
POU/POE technologies.  A major factor is whether
there is already in place a distribution system, versus
whether additional treatment must be installed in the
existing central system. Approximately 80% of the
total cost of any water utility is the installation and
maintenance of the distribution system. So in cases
where a distribution system would have to be in-
stalled to treat a contaminated drinking water source,
it may be more cost effective to install POU/POE
units.  An example of this would be a community
where each home has a well and it was discovered
that the ground water was contaminated with a
pesticide, fertilizer, or chemical. Rather than install
miles  of pipe, pumps, and storage facilities, a small
system could get state approval to install and main-
tain units in each home.  This might be economical
for upward of 100 homes depending on the cost of the
home  units versus the amount and difficulty of
installing a distribution system and central treatment
facility.  For those small  systems that already have a
distribution system in place, the break-even point
would be for fewer home units (< 50). However, in
situations where the existing treatment plant could
not be economically or physically upgraded or if the
water  quality is severely  degraded while in the
distribution system, POU/POE may once again be a
Figure 7- 7. Typical RO Unit under a kitchen sink.
36

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                                                                 Small Drinking Water Systems Handbook
 Table 7-1 Key Feature Summary of Commonly Used POU/POE Technologies  [26]
         Technology
                                  Comments
Filtration
Filtration of water supplies is a highly effective public health practice.  Microfiltration,
ultrafiltration, and reverse osmosis filtration systems have been shown to be
effective technologies for removing pathogens while being affordable for small
systems.
Activated Carbon
Activated Carbon is the most widely used POU/POE system for home water
treatment.  Easy to install and maintain with low operating costs, usually limited to
filter replacement.  Can remove most organic and some inorganic contaminants.
Membranes
Most POU membrane systems are reverse osmosis filters installed under the kitchen
sink, typically with either an activated carbon prefilter and an additional UV light
disinfection step to combat bacteria since the water is often stored under the sink
until used.
Ion Exchange
Commonly called water softeners when used for removing calcium and magnesium
from water.  Other types of units remove anions, such as arsenic (arsenate),
hexavalent chromium, selenium (selenate), and sulfate.
Distillation
Distillation is most effective in removing inorganic compounds, such as metal (iron
and lead) and nitrates, hardness, and particulates, from contaminated water. Also
removes most pathogens.  Can be effective in removing organic compounds
depending on the chemical characteristics of the compounds, such as water
solubility and boiling point. Distilling units have relatively high electrical demands
and require approximately 3 kilowatt-hours per gallon of water treated.
Air Stripping or Aeration
Aeration is a proven technology for removing volatile organic chemicals (for
example, dry cleaning fluid) from drinking water supplies for POE applications.
Aeration systems include: packed tower systems, diffused bubble aerators, multiple
tray aerators, spray aerators, and mechanical aerators.  Storage, repumping, and
possibly disinfection  facilities are needed after air stripping to distribute treated
water.  Air stripping is typically used for POE applications where high concentrations
of volatile organics need to be removed from drinking water where carbon can be
used only for short periods of operation.  Radon gas can also be removed by
aeration.
Modular Slow Sand Filtration
Slow sand filters housed in round fiberglass tanks (approx. 6 ft tall x 2.5 ft in
diameter) can treat 400-500 gallons daily. The systems are simple to operate and
have low capital (approx. $2,000) and operating costs. The unique feature of this
system is a very thin 1/8" thick filter blanket followed by a 1" thick polypropylene filter
blanket (similar to a furnace filter) to replace the biological mat that typically grows
on top of the sand (schmutzdecke). The blankets can simply be replaced when flow
is restricted without losing much sand or significant down-time.
Disinfection and Destruction
Disinfection is the most important consideration for POU/POE systems.  Disinfectants
that are generally used in POU/POE systems are ultraviolet light, ozone,  chlorine,
silver impregnated carbon, and iodine.
Chlorine - The most widely used water disinfectant.  Can be used in the  form of
liquid bleach, solid tablets, or generated onsite in portable generators.
Ultraviolet Light (UV) - Ultraviolet light is a popular home disinfection method in
combination with other treatment techniques.  Does not add chemicals that can
cause secondary taste and odor problems.  Units require little maintenance and
overdose is not a danger.
Ozone - Ozone has been used for disinfection,  destruction, and precepitation of iron,
manganese,  and some chemical contaminants. Ozone has to be generated and used
on-site as needed.
Iodine - Iodine has been  used as an alternative disinfectant to chlorine because it is
easier to maintain a  residual. However, iodine  will not remove iron or manganese,
nor will  it treat for taste and  odors.
                                                                                                               37

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      Small Drinking Water Systems Handbook
Table 7-2. Summary of Treatment Technologies and Costs [12]
Technology
Chlorine, Iodine
UV Ozone
Sub-Micron Cartridge
Filtration
Reverse Osmosis
Activated Carbon
Packed Tower
Aeration
Ion Exchange
Activated Alumina
Contaminants Removed
Microbial
Microbial
Protozoa, Bacteria
Microbial, inorganic chemicals,
metals, radium, minerals, some
organic chemicals
Organic Chemicals, radon, odors
(solid block can filter protozoa, and
some bacteria)
Radon, volatile organic chemicals,
tastes, odors
Inorganic chemicals, radium, nitrate
Arsenic, Selenium, fluoride
Initial Cost
Low
Moderate
Low
Moderate
Moderate
Moderate
Moderate
High
Operating Costs
Low
Low
Low to Moderate
High
Moderate to High
Low
Moderate to High
High
Operation and
Maintenance Skills
Low
Moderate
Low
High
Low
High
Moderate
High
       Low Cost:  $0 to $100   Moderate Cost: $100 to $1,000   High Cost: >$1,000
      practical alternative.  [27]

      Reverse  Osmosis  (RO) Home
      Membrane  Systems  Field Study

      The experiences presented below are from a field
      study (in Virginia) focusing  on removing naturally
      occurring fluoride at the tap by using a POU system.
      [28] The water being supplied to the homes was
      provided by a well located within the local subdivi-
      sion.  However, the driving force in the ultimate
      acceptance by the Commonwealth of Virginia was the
      POU treatment device's ability to provide finished
      water with acceptable levels of heterotrophic plate
      count (HPC). A public-private partnership between
      Virginia, EPA, and three POU vendors demonstrated
      the use of RO systems to reduce fluoride for this
      subdivision. This was a lower cost alternative to
      abandoning the well and installing a large transmission
      line to connect with a PWS several miles away.

      Prior to this project, no treatment existed at the
      subdivision's  well. The RO POU devices were
      designed to treat only the water used for drinking and
      cooking, and  in some homes, the ice-making units in
      refrigerators.  The devices consisted of a sediment
      prefilter, a high-flow,  thin film (HFTF) RO mem-
      brane, a storage tank, and an activated carbon post
      filter. Basic parameters, such as conductivity,
      fluoride, HPC, total coliform, chlorine residual, pH,
      sodium, total  dissolved solids (TDS) and turbidity, were
      used to evaluate the performance of the RO units.

      Fluoride reduction was easily achieved for the entire
duration of the study, maintaining levels below the
secondary maximum contaminant level (SMCL) of
2.0 mg/L. However, HPC counts were elevated and
the decision was made to centrally chlorinate at the
well and replace the HFTF membranes with chlorine-
resistant cellulose triacetate (CTA) membranes and
remove the activated carbon post-filter. Subsequent
sampling demonstrated satisfactory fluoride and HPC
levels.  Variances in fluoride and HPC concentrations
from site to site was explained by membrane degrada-
tion and water use. The life expectancy of the
membrane depends on the environmental conditions.
High temperatures, bacteria, and high pH have an
adverse affect on the membrane life and result in poor
performance.  Membranes were replaced when the
conductivity reduction decreased to 70% of the
influent.  It was observed that conductivity reduction
was generally lower than fluoride rejection, so this
became a convenient, inexpensive, and conservative
means of monitoring system efficacy.  A correlation
between HPC and chlorine residual was also ob-
served. In fact,  much of the project focused on
maintaining HPC levels below 500 cfu/mL.

Water quality sampling data indicated that the risk of
exceeding 500 cfu/mL at the tap was inversely
proportional to the chlorine residual in the post-RO
holding tank located under the kitchen sink. Any
time the residual exceeded 0.5 mg/L free chlorine, the
HPC limit was maintained, without exception.  This
is extremely relevant, because an RO membrane
allows some chlorine  to pass through, thus maintain-
ing a residual at the tap. In this case, the water
reaching each household typically exhibited chlorine
residuals of 1 to 1.5 mg/L.  Concentrations in the
38

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                                                           Small Drinking Water Systems Handbook
holding tank between 0.5 and 1 mg/L were observed
frequently, indicating 33 to 50% passage of chlorine
through the membrane.  This concentration decreases
over time in the finished water holding tank as it is
consumed through various oxidation reactions.
Because of this, it can be presumed that negligible
chlorine residuals indicate the unit has not been used
recently.

It was concluded that the HPC concern can be
eliminated by using chlorine-tolerant membranes and
by continually chlorinating the  subdivision's well. In
most cases, the RO storage tank unit was continually
refilled with chlorinated water.  The HPC depended
on the  chlorine residual in the storage tank, and
usually the residual chlorine remained high enough to
keep the unit clean.  However, if the units were not
used daily, stagnant water in the tank caused a loss of
residual chlorine,  and the water was susceptible to
microbiological growth. Researchers found that one
way to overcome this was to flush the tank daily.
This concept was  demonstrated at a business site
during  the study where the water was only used
sporadically.

Public Acceptance
At least 1 gallon per day (gpd) of RO water was
consumed by 77% of the homeowners, corresponding
to the 75% who used the system for all of their
drinking and cooking needs.  Just 6% of participants
claimed to rarely use the RO  water.  Although
demonstrating fluoride reduction with RO has been
done before, the challenge in this study was maintain-
ing microbiological integrity and gaining public and
regulatory acceptance for POU treatment. This
required an entirely different relationship between the
state authorities and the customers.  The initial and
exit surveys confirmed not only public acceptance,
but showed an increase in customer satisfaction with
the POU treatment.  When asked to rate the water
quality on a scale of 1^4, 52% of participants in the
initial survey rated the well water (not chlorinated)
quality as "fair" or "poor," while 77% rated the RO
water as "good" or "very good" shortly after installa-
tion. In the exit survey one year later, 94% rated the
RO water as good or very good, showing a significant
increase in the acceptance of the POU systems.  This
acceptance may be due, in part, to the treated RO
water also being softer than the raw water.

The average RO water quality was rated 1.5 points
higher  than the average tap water quality.  The
average rating was calculated by summing the
individual ratings and dividing by the number of
responses. In the exit survey, RO water quality
averaged 3.5 points on a scale of \-A, while well
water quality averaged 2.1 points. Moreover, RO
water quality was always rated at least as high or
higher  than the well water quality, even when the
non-chlorinated well water was compared to chlori-
nated RO water.  This is noteworthy because the
switch to a chlorinated supply initially precipitated a
number of negative comments about taste.  Microbio-
logical integrity was not an issue for consumers
whereas it was the primary driver from the state
perspective.

Documentation of the  increasing contamination of
U.S. ground water supplies grows almost daily.
Small water systems have been,  and will continue to
be, the most vulnerable and the least capable of
meeting current and future drinking water regula-
tions. But, competitive options and alternatives are
available in terms of drinking water treatment
technology.  Central treatment can no longer be
thought of as the only  solution, nor can it be thought
of as temporary or for aesthetics only.

AOP POE for PCE and TCE Removal, Vernon, CT
Most ozone whole-house POE applications for
drinking water in the past have been used for oxida-
tion of inorganic contaminants, such as iron and
manganese.  Recent projects have focused on the use
of ozone in conjunction with ultraviolet light and
granular activated carbon  (GAC) for the destruction
of synthetic organic contaminants in groundwater and
disinfection of surface water supplies.

Two shallow drinking water wells in Vernon, CT,
were found to have elevated perchloroethylene (PCE)
and trichloroethylene (TCE) concentrations. As a
pilot project, a system comprised of a small AOP was
installed on one of these wells and provided up to 10
gallons per minute. The unit successfully served three
homes essentially as a packaged central treatment
system, although it was originally designed as  a home
POE unit.

The AOP system consisted of an ozonator, an UV
light chamber, two GAC tanks, two treated water
storage tanks, a water meter, and an electric meter.
Water from the well was sent into the ozonation
chamber where ozone was fed into the water by a
venturi. A venturi forces a gas into a liquid (such as
ozone into water). The ozonated water then entered
the UV light chamber and then a contact tank where
the water was mixed for 3.5 minutes to achieve 100%
ozone saturation. The treated water then entered the
two GAC units where any residual ozone is converted
to oxygen, and any remaining contaminants are
removed. The treated water was  then stored in  the two
storage tanks and then distributed to the three houses
via the water meter.

The AOP system was tested over a two-month  period,
and it treated more than 15,500 gallons of water. The
test results show  an 80-90% reduction in PCE
                                                                                                        39

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       Small Drinking Water Systems Handbook


       concentrations following UV/O3 (with an influent
       concentration between 250 and 663 ng/L). The PCE
       concentrations following the GAC units were non-
       detectable. The capital cost of the system was
       estimated to be approximately $6,000 (in 1991
       dollars) with a maintenance cost of approximately
       $150 per year. This amount includes electricity cost
       and GAC replacement costs.

       Ozone POE, Spruce  Lodge, ME
       Figure 7-2 shows the POE unit installed in the cellar
       of a sportsman's camp in Spruce Lodge, Maine, that
       served up to 30 hunters and fishermen daily in a
       lodge and four cabins. The raw water is filtered
       through garnet followed by ozone injection (0.4 mg/L)
       and then passes by a UV light to a holding tank.

       The lake's raw water quality was  good. Finished and
       distributed water was negative for total coliform.
       HPC values varied somewhat with one episode
       exceeding 500 cfu/mL.  The variability could have
       been the result of biofilm in the plumbing leading to
       one of the cabins.  The cabin had not been occupied
       for days prior to sampling, thus resulting in old
       stagnant water in the plumbing system's service lines.

       Ozonation byproducts for the treated water were
       analyzed during this brief study and indicated lower
       levels of all but one of the DBPs found in the raw
       water. This could have been the result of the  overall
       good quality of the raw water and lack of ozone-
       demanding compounds, allowing reduction of the by-
       products already formed in the raw water.

       Low-humidity oxygen is required to produce  ozone.
       This POE unit used silica gel to remove moisture
       from the air in the cellar rather than  install an
       expensive oxygen generator. Operational concerns
       centered on the frequency of reconditioning the air-
       drying material. Because of the high humidity in the
       cellar of the Lodge, the silica gel had to be recondi-
       tioned every few days.  Although not expensive or
       time consuming (30 minutes in an oven at 325°C),
       constant attention to this might not be maintained in a
       household and hence affect ozone generation  and
       disinfection efficiency.  [26]
Figure 7-2.  AOP POE unit installed in a cellar.
40

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                                                         Small  Drinking Water Systems Handbook
8.0  Remote  Monitoring/Control
Many alternative treatment systems/technologies can
be equipped with up-to-date and modern sensor and
operating devices that can be monitored from remote
locations.  This fact led EPA to consider remote
monitoring and control technology to improve
monitoring/reporting and reduce operation and
maintenance (O&M) costs. Although such telemetry
equipment could double the purchase cost of a
package plant, payback can be quickly realized
through reduced chemical use, low residue generation
(disposal), and increased reliability.  Also, the cost of
subsequently networking multiple package plant sites
or water quality monitoring devices also  decreases
after the initial cost for the telemetry equipment. It
has been demonstrated that various technologies are
being appropriately designed for small systems.
These will ultimately produce a better quality of
drinking water, accommodate the resources of small
systems, increase the confidence level of the cus-
tomer, operator and regulator, and comply with the
monitoring and reporting guidelines.  This section
will discuss the "lessons learned" in the use of remote
monitoring and control for treatment systems.

Small systems did not always use Remote Telemetry
Systems (RTS - a.k.a. Supervisory Control and Data
Acquisition [SCADA]) to their fullest potential due to
complex operating systems and  controls that usually
required specially trained computer programmers or
technicians and costly service agreements. In the last
few years, RTS vendors have changed the way they
design and fabricate their systems, thus making them
more accessible to small drinking water treatment
operators.

The application of RTS to operate, monitor, and
control small systems from a central location (an
electronic "circuit rider") is believed to be one mecha-
nism that can reduce both MCL and M/R violations.

Through the application of RTS, the EPA has demon-
strated that filters can be operated more efficiently for
particle removal, disinfectant doses altered in real-
time in response to varying raw  water conditions, and
routine maintenance and chemical resupply sched-
uled more efficiently. Small independent systems can
contract with an off-site O&M firm or join with other
small system communities or utilities to either work
out schedules to monitor via telemetry or hire an
O&M services provider, while maintaining owner-
ship. This type of approach would provide the small
system with the economies-of-scale medium and
larger systems have in purchasing  supplies, equip-
ment, and power, while also possibly receiving a
better trained operator.
  The following factors must be considered before
  purchasing a RTS:

  •  Does the water treatment system justify the
      requirement for a remote RTS system (is it
      remotely located)?

  •  Is the treatment system amenable (can water
      quality instrumentation and operational
      controls "send and receive" data in real-time)
      to automation?

  •  What types of communication media can be
      used (phone, radio, cellular, etc.)? See Figure
      8-1

  •  How much automation and control is available
      on the treatment system?

  •  What type of RTS system is needed? Is the
      goal to monitor, control, or both?

  •  How many parameters are going to be
      monitored and/or controlled?

  •  Are there any specific regulatory monitoring
      and reporting requirements?                 [32]

EPA has been evaluating a variety of "small" RTSs
that allow a single qualified/certified operator to
monitor and control the operation  of several small
treatment systems from a central location.  Using
RTS results in optimum utilization of time for onsite
inspections and maintenance, thus allowing the
operator to visit only  the problematic systems/sites
and better schedule the maintenance of these systems.
The expected results from an appropriately designed
and successfully deployed RTS are [31]:

•  enhanced water quality,

•  regulatory compliance, and

•  reduced cost for  small communities

RTS Selection and Implementation
It is important to  understand the treatment system
operation, location, and other environmental factors
when engineering and designing a RTS for remote
operation and maintenance.

The above factors will determine the need and the
basic design of the RTS system. These factors will
also help to determine if the system  will complement
the needs of the treatment system and the  utility
services. The cost of retrofitting a treatment system
for remote operations can be prohibitive. Many small
                                                                                                     41

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       Small Drinking Water Systems  Handbook
Table 8-1. Amenability of FITS to Treatment Technologies
Used for Small Water Systems [32]

Technology
Air Stripping
Oxidation/Filtration
Ion Exchange
Activated Alumina
Coagulation/Filtration
Dissolved Air Flotation
Diatomaceous Earth Filtration
Slow Sand Filtration
Bag and Cartridge Filtration
Disinfection
Corrosion Control
Membrane Filtration Systems
Reverse Osmosis/Nanofiltration
lectrodialysis Systems
Adsorption
Lime Softening
Amenability for
Automation/Remote
Monitoring
4-
1 -
3-
1 -
1 -
1 -
3-
3-

4-
3-
3-
4-
4-
3-
1 -
& Control*
5
2
4
2
2
2
4
4

5
4
4
5
5
4
2
 *A rating scale of one to five (1 to 5) is employed with one (1) being
 unacceptable or poor and five (5) being superior or acceptable.

       treatment systems currently in use were not originally
       designed for remote operations. Rural areas have
       little or no electronic hardware to communicate with
       a telemetry system. Thus, the cost of upgrading a
       treatment system for remote operations can be
       significant.  It is essential that the treatment system
       be fairly amenable to automation. Table 8-1 identifies
       the current amenability of small package plant
       treatment technologies to remote telemetry.

       Many of these treatment technologies are available as
       package plants with some degree of automation
       designed specifically  for small systems. The mem-
       brane technologies are extremely amenable to
       automation and remote control and also provide
       efficient removal for a wide range of drinking water
       contaminants.

       Federal regulations require all small PWS  operators
       to monitor to assure the quality of the treatment
       processes. Constant remote monitoring of the water
       quality has provided substantial savings in time and
       travel cost for O&M.  It has been determined that
       remote telemetry can support regulatory reporting
       guidelines by providing real-time continuous moni-
       toring of the water quality and reporting the informa-
       tion electronically. However, due to concerns of
       assuring the best water quality to the consumer, many
       state regulators resist accepting the remote monitor-
       ing guidelines.   Table 8-2 presents a range of costs
       for RTS system components.

       Long-term real-time remote monitoring can provide
data that can be used to significantly enhance
treatment system operation and reduce system
downtime. The overall benefits include:

•    Improved customer satisfaction, improved
     consumer relations and, other health benefits.

•    Satisfies regulatory  recordkeeping and reporting
     requirements.

•    Reduces labor costs (associated with time and
     travel) for small system operators.

•    Provides the capability to instantly alert
     operators of undesirable water quality and/or
     other changes  in treatment system(s).

•    Troubleshooting can be performed remotely,
     reducing downtime  and increasing repair
     efficiency.

•    Fully automated treatment systems can identify
     monitored parameter trends and adjust operating
     parameters accordingly.

•    Provides an attractive alternative to fixed
     sampling and operation and maintenance
     schedules.

A real world example of a small  system equipped
with remote monitoring and control is included in
Section 9.0 of this document.
Table 8-2. Cost Estimates of SCADA System
Components [32]
SCADA System
Component
Hardware
Software
Communication
Medium
Instrumentation
Component Option
Main Computer
SCADA Unit
Operating System
Telemetry System
Data Collection & Loggers
Telephone
Cellular
Radio
Satellite
Valves
Switch
Sensor
Range of Costs
$1,000- 3,500
500 - 30,000
$250 - 750a
500 - 30,000b
250 - 8,000
$75-125c
250 - 500d
1,500- 3,500e
20,000 - 75,000r
$25-1,5009
25 - 3009
350 - 85,000h
aOperating system software is usually included in the purchase price of a computer.
bSCADA software is usually included in the purchase price of the hardware.
'Monthly service charges are estimated.
^Activation, roaming, and monthly service are estimated and included.
transmission cost of Integrated phone, cellular, radio frequency, and satellite
system.
Satellite systems cost for transmissions, monthly service and activation charges are
estimated
9Cost per valve and/or switch.
hCost per individual sensor or sensor system.
42

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                                                    Small Drinking Water Systems Handbook
Remote
Location
                                   Communication
Central
 Office
                                Radio (RF) Communication

                                          OR
                                      Direct Wire

Figure 8-1.  Possible layout(s) of a Remote Telemetry System.
                                                                                            43

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     Small Drinking Water Systems Handbook
44

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                                                               Small Drinking Water Systems Handbook
       9.0     A  Real  World  Packaged  Solution
      In May 1991, EPA provided funding to support a
      research project titled "Alternative Low Maintenance
      Technologies for Small Water Systems in Rural
      Communities." This project involved the installation
      of a small drinking  water treatment package plant in a
      rural location in West Virginia. The primary objective
      of this research was to evaluate the cost-effectiveness
      of membrane package plant technology in removing
      microbiological contaminants.  The secondary
      objective of this project was to automate the system
      and minimize O&M costs.

      The EPA test site is located in rural McDowell
      County, West Virginia. The treatment system is
      located approximately  12 miles from the McDowell
      County Public Services Division (MCPSD) office
      through Appalachian Mountain terrain. Figure 9-1
      shows the town MCPSD services.  The water source
      is an abandoned coal mine. The raw water quality
      parameters are shown in Table  9-1.  Prior to 1994, an
      aerator combined with a slow sand filter was used to
      treat water at this site (see Figure 9-2). This com-
      bined unit had been operational for over 60 years and
      needed substantial repairs. Water flowed by gravity
      from the abandoned coal mine  to the aeration trays
      built over a six-foot diameter slow sand filter. A
      hypochlorinator disinfected the filtered water, which
      then flowed by gravity through the distribution
      system to the consumer.  The volume of water from
      the mine was sufficient for the small rural community
      of approximately 100 people.
Figure 9-1.  McDowell County.
      The system had several problems. The filtration was
      not very effective, and the operator used excess
      chlorine for disinfection. The water quality tests
      indicated that the residual chlorine content was
Table 9-1. Raw Water Quality and
Contaminant Specifications
Total Coliform
Fecal Coliform
Hetrotrophic Plate Count (PCA)
Hetrotrophic Plate Count (R2A)
Fecal Streptococci
Escherichia coli
TOX
Total Hardness (CaCO3)
Specific Conductivity (micromhos)
Ca
Mg
Na
S04
NO3
1.150CFU/100
650CFU/100
900 CFU/mL
37,000 CFU/mL
520 CFU/mL
100CFU/ml
8.2 ug/L
1 80 mg/L
350 micromhos
60 mg/L
9 mg/L
4 mg/L
1 2 mg/L
1 mg/L
greater than 4.0 mg/1 as received by the consumer.
Consumers were being charged $20 per month for
water that distinctly tasted and smelled like chlorine.

An engineering study conducted by MCPSD esti-
mated the cost of a new conventional water treatment
system (to replace the existing treatment system and
distribution system) to be $328,000, resulting in a
cost of $10,933 per customer. Consumers considered
this an impractical and unacceptable solution.  It was
essential that the replacement technology operate in a
rugged environment with minimal maintenance.
Also, the treated water quality characteristics were
                                                        Figure 9-2.  Old treatment system.
                                                                                                          45

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      Small Drinking Water Systems Handbook
      required to be consistent with the SWTR and the
      Total Coliform Rule as described below //1]:

      •    No more than one sample per month may be
           total coliform positive,

      •    HPC must be < 500 mL if the chlorine residual
           value is < 0.2 mg/L

      •    Turbidity of the treated water must at all times
           be <5NTU and normally can not be >0.5NTU

      Thus, the EPA and MCPSD investigated various
      alternative economically feasible technologies. Based
      on a review of available technologies, the EPA
      determined that a packaged UF system would be
      ideally suited for this location.  In 1992, a packaged
      UF water treatment system was purchased and
      installed at this site.

      Test  Site Treatment Technology Overview—
      Packaged UF System
      The packaged UF system has an overall dimension of
      12'10"L x 7'H x  3'W with an approximate empty
      weight of 800 pounds  (see Figure 9-3).  The picture
      shows the front view of the system as purchased and
      installed in 1992. The main system components of
      the UF system are as follows:

      •    Three  8" x 40" spiral-wound UF membrane
           cartridge elements arranged in series and
           contained in a fiberglass vessel. The UF
           elements are polymeric spiral-wound type with a
           nominal MWCO  of 10,000.

      •    The package UF  system includes a control panel,
           feed pumps, recirculation pumps,  10-25-micron
           bag pre-filter, 30  gallon cleaning tank, a chlorine
           monitor, electrically actuated control valves,
           temperature and pressure gauges, and sight
           rotometers

      •    The unit is interconnected with Schedule 80
           poly vinyl chloride (PVC) piping.  The UF
           system is designed to produce 10,000 gallons per
           day (GPD) treated drinking water.

      The packaged UF system was installed on a new
      cement slab and the community constructed a 12' by
      24' cinder block building to secure and protect the UF
      system (see Figure 9-4).

      Overview of Remote  Monitoring and Control
      Technology Installed at the Test Site
      The packaged UF system as initially installed used a
      manufacturer provided programmable logic controller
      (PLC), along with PLC controllable hardware for
      automation. The UF system also included several
      instruments and  sensors, such as an online pH sensor,
      online chlorine sensor, pressure gauges, etc.  The UF
Figure 9-3.  Packaged UF System.
Figure 9-4.  New cinder block building.

system operating and water quality parameters were
manually logged and recorded from the instrument's
analog/digital displays.  In 1996, the EPA developed,
installed, and tested a RTS at the site.  The RTS used
commercially available hardware. The RTS software
was a MSDOS-based system that was hardware
specific, not very user-friendly, and the overall cost of
ownership was not practical. Thus, the system
operated with proprietary, EPA-developed software.

In 1998, the EPA updated the RTS unit with a
commercially available, off-the-shelf,  user-friendly,
Microsoft® Windows®-based RTS. Figures 9-5 and 9-
6 present two operator computer screen shots. The
RTS selected was fairly inexpensive, smart, user-
friendly and scaleable. The capital cost for the
hardware and instrumentation was approximately
$12,000, and the total cost (including technical
support, training, and set-up) was about  $33,000.
The EPA worked with MCPSD to remotely monitor
the UF system for water quality.  The RTS  is also
being evaluated for its effectiveness in fulfilling  the
regulatory monitoring and reporting requirements,
and its effectiveness in reducing the manpower
46

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        Tamral Tr- Nit Qu.
                       •
                b'lvr.'.vii^enLci-. Piotecliur
       Buchannan Treatment Plant
             Coalwood, WV
          Remote Telemetry and Control System.
       This system hai been equipped with a smart remote
       telemetry unit Hit., The EPA ts currently
       evaluating the cost benefit potential or this system to
       support regulatory reporting guidelines by providing
       real-lime continuous moniloilnii of (lie walei
       mill reporting di« information rirrinmlraUv. Other
       benefites associated with remote telemetry for the
       small treatment plant art: preventive
       troble shooting, and reduced labor costs
       Small Drinking Water Systems Handbook


operating parameters without operator intervention
makes the system "smart." This system can also be
programmed to dial-out and page the operator during
"alarm" conditions.  The existing package plant was
upgraded and modified as necessary to accommodate
RTS functionality. MCPSD currently operates and
maintains this system.  The RTS has operated trouble
free since installation. Based on the initial success,
EPA has recently installed similar units at two other
locations within McDowell County.
Figure 9-5.  Welcome screen.
Figure 9-6.  System summary (note the high chlorine alarm).


       requirements during the operation and maintenance
       of the UF system.

       This RTS can be remotely programmed to optimize
       treatment system operation based on observed trends.
       For example, if the monitored trends indicate that
       during a certain period the storage tank water levels
       are lower than normally observed during that time,
       the system can be programmed to automatically
       increase the water supply to the storage tank. This
       type of trend-based adjustment can potentially
       eliminate water supply disruptions. This ability of the
       RTS unit to adjust treatment and distribution system


   The remote monitoring and control system proved
   to be a useful tool for troubleshooting.  Specifi-
   cally, MCPSD was able to monitor and download
   activity logs of the system and monitor system
   performance over time. This  enabled MCPSD
   personnel to schedule maintenance activities based
   on observed pressure data.  The system also
   helped MCPSD to monitor the system operation
   remotely during inclement weather conditions.
                                                                                                                    47

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     Small Drinking Water Systems Handbook
48

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                                                         Small Drinking Water Systems Handbook
10.0    Funding and  Technical  Resources
Most federally funded water projects are financed by
the EPA's Drinking Water State Revolving Fund
(DWSRF) and/or the U.S. Department of
Agriculture's Rural Utilities Service (RUS) [33].
There are also various foundations, bank programs,
state programs, other federal programs, and professional
organizations that provide grant and loan assistance.
This section briefly describes each of these resources.

EPA  Drinking Water State
Revolving  Fund  (DWSRF)

EPA is aware that the Nation's water systems must
make significant investments to install, upgrade, or
replace infrastructure to continue providing safe
drinking water to their 250  million customers.
Installing new treatment facilities can improve the
quality of drinking water and better protect public
health. Improvements are also needed to help those
water systems experiencing a threat of contamination
due to aging infrastructure systems. In order to
improve small drinking water systems and further the
health protection objectives of the SDWA  amend-
ments, EPA entered into agreements with "eligible"
states to make capitalization grants available through
the state programs. The 1996 SDWA Amendments
established the DWSRF to make funds available to
PWSs to finance infrastructure improvements.  The
program also emphasizes providing funds to small
and disadvantaged communities and to programs that
encourage pollution prevention as a tool for ensuring
safe drinking water.  Section 11.0 of this document
identifies the various state agencies and their web
locations.
    To Find Out More About DWSRF:
  www. epa.gov/safewater/dwsrf.htm/
The DWSRF program required that States develop a
priority system for funding infrastructure projects
based on three criteria established by the SDWA
Amendments. States are also required to solicit and
consider public comment when developing their
priority systems.  Projects are ranked and funding is
offered to the highest ranked projects that are ready to
proceed. Priority goes to those eligible projects that:

•  address the most serious risk to human health;

•  are necessary to ensure compliance with the
    requirements of the SDWA Amendments; and,

•  assist systems most in need,  on a per household
  Capacity development refers to the technical,
  financial, and managerial capability needed to
  consistently achieve the public health protection
  objectives of the Safe Drinking Water Act (SDWA).
  A key component of the 1996 SDWA Amendments,
  capacity development ties into the Drinking Water
  State Revolving Fund (DWSRF) in two important
  ways. First, states may set aside funds  from their
  DWSRF allotments to develop and implement
  capacity development programs.  Second, the EPA
  is required to withhold DWSRF funds  from states
  that fail to implement capacity development
  provisions.
    basis, according to State-determined
    affordability criteria.

In order to qualify for DWSRF funds, states must
have an EPA-approved capacity development pro-
gram and an operator certification program. Funds
can be used for loans, loan guarantees, and as a
source of reserve and security for other (leveraged)
funds.  States must also contribute an amount equal to
20% of the total federal contribution.  As loans are
paid back, the State can re-loan the money to other
systems, thus the term "revolving" in DWSRF. Any
system that gets a loan must demonstrate that it has
the  technical, financial, and managerial capacity
("capacity development program") to operate its
system for the long-term.

Since 1997, Congress has authorized $9.6 billion for
the  50 states and Puerto Rico. Currently, the indi-
vidual State grants range from $7 million to $80
million per year.  Loans can have interest rates
  Eligible project categories for DWSRF include:

  Treatment - Projects designed to maintain compli-
  ance with regulations for contaminants causing
  health problems.
  Transmission and Distribution - Projects related to
  installing or replacing pipes.
  Source - Projects that rehabilitate wells or develop
  new water sources to replace contaminated sources.
  Consolidation - Projects that combine sources or
  systems if one is unable to maintain technical,
  financial, or managerial capability.
  Creation of New Systems - Projects that establish
  new systems or projects involving consolidation of
  multiple systems that have severe problems.
                                                                                                     49

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      Small Drinking Water Systems Handbook
      For a state to be "eligible" for DWSRF, it needs
      to have an EPA-approved operator certification
      program. Each state has different needs and so
      programs vary state-to-state. Training and
      certification program ensures drinking water
      operator competency, and therefore protects
      public health.  In almost all states, some training
      is provided by the Rural Water Association and/or
      the local chapter of AWWA. These classes are
      generally free or very low cost. But, sometimes
      small systems simply can't provide the money to
      cover an operator's travel or lodging costs, even if
      the tuition is free. EPA has initiated a grant
      program that will make money available to cover
      certain training and certification expenses.

      As required by SDWA, EPA must reimburse the
      costs of training for people operating community
      and nontransient noncommunity public water
      systems serving 3.300 persons or fewer that are
      required to undergo training. The reimbursement
      is to be provided through grants to states. EPA
      will determine the total amount that each state is
      to receive to cover the reasonable costs for
      training and certification for all such operators.

      Funding assumptions include money to cover a
      per diem for unsalaried operators, tuition costs  for
      training classes, fees for initial certification
      renewal, and mileage.  States may apply for and
      receive the expense reimbursement grant funds
      once their operator certification program has
      received EPA approval to apply for and receive its
      expense reimbursement grant. As part of the
      grant application, states must submit a work plan
      and annual progress report outlining how these
      funds are to be used.
      Several financing options are available for
      communities that seek DWSRF funding, including:
      Low-Interest Loans—Loan rates range between
      zero percent and the current market rate, with a 20-
      year repayment period.
      Refinance or Purchase Local Debt—Helps to
      reduce a community's cost of borrowing.
      Purchase Insurance or Guaranteed Local Debt—
      Can improve credit market access or reduce
      interest rates.
      Leverage Program Assets—Through issuing bonds
      to increase the amount of funds available for
      projects.
      Disadvantaged Assistance—Provides help by
      taking an amount equal to 30 percent of a capitali-
      zation grant for loan subsidies or extending the
      repayment period from 20 to up to 30 years.
between 0% and the market rate. Special help is
available for disadvantaged communities. DWSRF
guidelines require that at least 15% of the loan fund
be used for small PWSs.

U.S.  Department of Agriculture
Rural  Utilities  Service (RUS) Loan
and Grant Program

The RUS and its predecessor, the Farmers Home
Administration, have provided more than $25 billion
in loans and grants since 1940.  RUS has often been
described as the "funder-of-last-resort" for communi-
ties that have nowhere else to turn.  [29]  The RUS
provides both loans and grants to rural communities
for drinking water, wastewater, solid waste, and storm
water drainage projects.  These  are administered
locally by state and district Rural Development
offices.  RUS  loans are designed especially for
communities unable to obtain money from other
sources at reasonable rates and terms. Funds may be
used to install, repair, improve, or expand rural water
facilities.  Expenses for construction, land acquisi-
tion,  legal fees, engineering fees, interest, and project
contingencies can also be covered.  The RUS interest
rates are set at three levels: the poverty line rate, the
intermediate rate, and the market rate, each of which
has specific qualification criteria.

State Rural Development offices can provide specific

   The current interest rates  (for the second
   quarter of year 2001 that apply to all loans
   issued from April 1 through June 30, 2001) are:
   poverty line: 4.5 percent (unchanged from the
   previous quarter);
   intermediate: 4.75 percent (down 0.25 percent from
   the previous quarter); and
   market: 5.125 percent (down 0.375 percent from the
   previous quarter).
information concerning RUS loan requirements and
application procedures. For the phone number of your
state Rural Development office, contact the National
Drinking Water Clearinghouse at (800) 624-8301 or
(304) 293-4191.

Other Financial Assistance
            To Find Out More About RUS:
   www.usda.gov/rus/water/states/usamap.htm
50

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                                                          Small Drinking Water Systems Handbook
Programs
The following types of funding tools can also be used
to buy equipment.  Each offers advantages and
disadvantages not only in eligibility and terms, but
also in the amount of time and information needed to
fill out the application forms.

Loan Programs
Commercial loans are available from banks or other
financial institutions and the application process can
be relatively quick, but the interest rates are generally
higher with less favorable pay-back rules.  State
programs generally offer better rates and terms for
those systems that are ineligible for conventional
types of financing.

Grant Programs  [34]
Grants, which are awarded to a state or local govern-

CoBank, a federally charted financial institution
owned and patronized by about 2,400 agricultural
cooperatives and rural utilities, provides one
popular type of loan program.  As customers, these
cooperatives and utilities provide capital to the
bank by securing equity based on money borrowed.
Long-term and interim loans are available for
construction and equipment financing if applicants
meet the eligibility requirements. PWSs serving a
population of fewer than 20,000 that can show an
acceptable credit risk are generally eligible.
                                           [347
    To Find Out More About CoBank:
           www. cob an k. com
ment or nonprofit organization, are sums of money
that do not have to be paid pack. They can be
awarded by the federal government (e.g., Community
Development Block Grants) to state or local govern-
ments or by states to local governments.  Applying
for grants, however, can require a significant commit-
ment of time by utility personnel.  In addition, the
availability and timing of the grant award may not
match the utilities' needs. Most grant programs
possess limited funds, and competition for these
funds may forestall funding for many projects.
Grants also have project eligibility requirements, and
some programs may specify that the grantee provide
a share of the total project funds.

The Department of Housing and Urban Development
(HUD) provides grants to drinking water utilities
through the Community Development Block Grant
(CDBG) program. Applications must be filed
through the appropriate state government office;
states have the authority to administer the distribution
of the HUD funds. Grants are targeted to PWSs
serving low- and moderate-income households, and
drinking water treatment systems are among the types
of projects eligible for assistance. On average, the
grants cover 50 percent of project costs, although
areas experiencing severe economic distress are
eligible for grants that cover up to 80% of project
costs.

The Department of Commerce provides grants
through the Economic Development Administration's
Public Works and Development Program.  Applica-
tions must be submitted to the state economic
development agency; states  are authorized to admin-
ister the funds.  The drinking water project must be
located in a community or county determined to be
economically distressed, and the project must be
directly related to future economic development.
Some restrictions apply when grants are provided in
conjunction with other financial assistance.  The
combined funding is limited to 80 percent of the total
project cost.

Qualifying applicants in designated Appalachian
Regions in 13 states can also apply to the Appala-
chian Regional Commission (ARC) for grants in
conjunction with the Tennessee Valley Authority.
Local development districts provide assistance in
preparing  an applicant's proposal.  Priority funding is
determined each year by the state governors, Appala-
chian district personnel, and ARC members. All
projects that qualify for grant funding must be
directly related to economic development, housing
development, or downtown revitalization and im-
provement. Drinking water treatment systems are
among the types of projects eligible for assistance.

One restriction of ARC grants is that they are limited
to 50% of project costs and  require the recipients to
provide the other 50%.  An exception is made for
economically distressed counties, which can receive
80% and must supply only 20%. In 1992, 90 counties
out of 398 in the Appalachian region fit within this
"distressed" category.  However, to raise the remain-
ing 20% of funds, owners of small systems in
distressed counties should aggressively seek other
innovative sources of funding.

The Indian Health Service (IHS), which is part of the
Department of Health and Human Services, provides
grants for projects undertaken by American Indians
and Alaska Natives. In 1959, Congress passed the
Indian Sanitation Facilities Act to provide improved
health conditions by improving sanitation, sewer,
solid waste, and drinking water facilities. To date,
more than $1 billion has been spent on  the effort, and
more than 182,000 homes have received water, sewer,
                                                                                                        51

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      Small Drinking Water Systems Handbook
      and solid waste services for the first time. IHS grants
      support health aspects rather than economic develop-
      ment or environmental preservation and do not
      include funding for operation and maintenance. No
      matching funds are necessary, and IHS grants can be
      consolidated with those from other agencies.

      No-interest loans
      In 1989, the Rural Electrification Administration
      (REA) implemented a program to promote projects
      that "will result in a sustainable increase in the
      productivity of economic resources in rural areas and
      thereby lead to higher levels of income for rural
      citizens." This program is the Rural Economic
      Development and Grant Program. The program
      makes no-interest loans available for up to 10 years
      and grants of as much as $100,000.  The local REAs
      act as sponsors for the actual project owners. Drink-
      ing water projects are eligible for these no-interest
      loans.

      Table 10-1 provides a summary of these funding
      sources. Technical and administrative assistance for
      applying for these funds can be obtained from various
      agencies identified in Table 10-2.

      Foundations
      Private foundations are another possible source of
      funding for small PWSs. A source of information
      about foundations that provide grants, The Founda-
      tion Directory, provides basic descriptions of founda-
      tions that have $1 million or more in assets or that
      annually award $100,000 or more. Information about
      smaller foundations can be obtained from the local
      Internal Revenue Service (IRS) office. The IRS
      annually collects Form 990-PF  (Return on Private
      Foundations) from foundations  of all sizes, and it
      compiles information about the foundations' inter-
      ests, restrictions, application procedures, and dead-
      lines.

      Information about foundations can also be obtained
      from Source Book Profiles published by The Founda-
      tion Center, which contains information about the
Table 10-1. Federal Funding Programs for Small Public
Water Systems
Contact
Appalachian Regional Commission (ARC)
Department of Housing and Urban
Development (HUD) Community
Development Block Grants
Economic Development Administration
(EDA)
Indian Health Service (IHS)
Telephone
(202) 884-7799
(202) 708-2690
(202) 482-5081
(301)443-1083
Table 10-2. Technical and Administrative Support for
Small Public Water Systems
Contact
American Water Works Association
National Rural Water Association
Rural Community Assistance Program
Rural Electrification Administration (private;
provides some financial funding)
Rural Information Center
National Drinking Water Clearinghouse
Telephone
(303) 794-7711
ext. 6191
(580) 252-0629
(202) 408-1273
(202) 720-9540
(800) 633-7701
(800) 624-8301
thousand largest foundations. Also, the Cooperative
Assistance Fund represents foundations that pool
their funds to make program-related investments
primarily for low-income urban and rural communi-
ties.  Table 10-3 lists a number of private foundations
providing backing to rural economic development
programs.

Technical Resources -
Environmental Technology
Verification  (ETV),  Drinking Water
Systems Center

ETV Program Overview
Historically, the EPA has evaluated technologies to
determine their effectiveness in preventing, control-
ling, and cleaning up pollution. To accelerate the use
of environmentally beneficial technologies, the EPA
established the Environmental Technology Verifica-
tion (ETV) program to collect and disseminate
quality-assured data on the performance and opera-
tion and maintenance issues of specific-model
commercial-ready environmental technologies.

Important Principles
The ETV program does not certify product conform-
ance to a standard. There are no pass/fail criteria
associated with the ETV process. The ETV program
offers an opportunity for characterizing product
performance under a predetermined set  of test
conditions.  The ETV program offers flexibility to
participating manufacturers and vendors for technol-
ogy evaluations as either short pre-screening studies
on narrowly defined water quality and operating
conditions or  more comprehensive verification
evaluations over multiple seasons of testing and/or
multiple testing locations under varying conditions.

ETV testing results become public information.
Manufacturers involved in a product evaluation
52

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                                                           Small  Drinking Water Systems Handbook
Table 10-3. Foundation Backing Rural Economic Development Program
Foundation
Mary Reynolds Babcock
Foundation
Otto Bremer Foundation
Ford Foundation
W.K. Kellogg Foundation
Charles Stewart Mott
Foundation
Northwest Area Foundation
Telephone
(336) 748-9222
(888) 291-1123
or
(651) 227-8036
(212) 573-5000
(616)968-1611
(810) 238-5652
(651) 224-9635
Support Available
Grants include operating support for smaller organizations for
rural grassroots groups, primarily in North Carolina and the
Southeast.
Grants include some operating support for rural poverty
programs and support to strengthen the rural economy of
Minnesota, North Dakota, and northwestern Wisconsin.
Grants for experimental programs about rural poverty that can
inform public opinion
Grants for collaborative rural delivery of human services, rural
leadership development, and training local government officials
Grants for startup capital and capacity building to create
economic opportunities for low-income people
Grants for rural development in Idaho, Iowa, Minnesota,
Montana, North Dakota, South Dakota, Washington, and Oregon
receive an ETV Verification Report and Verification
Statement (a 5- to 6-page summary document) that
describes their product and its performance results
based on the specified evaluation conditions.

Participation in the ETV program by manufacturers is
voluntary. However, ETV reports can be valuable
tools for vendors through dissemination of their
equipment's performance results, and support toward
achieving regulatory and market place acceptance.

Drinking Water Systems  Center
On October 1, 2000, the EPA entered a joint venture
with NSF International to form the ETV Drinking
Water Systems (DWS) Center to provide independent
performance evaluations of treatment technologies
with the goal  of raising awareness for new product
applications.  The DWS Center efforts include
evaluation of  a wide range of treatment products from
complete package systems to individual treatment
modules or components.  Direction and prioritization
of ETV activities are provided by a stakeholder input/
feedback process. DWS Center stakeholders include
representatives from State and Federal regulatory
agencies, manufacturer-vendor groups, water utility
and technology-user organizations, and the scientific-
engineering-technology community.

Test Plans and Protocols
The DWS Center has nine contaminant-specific
verification testing protocols and 23 technology-
specific test plans that outline testing procedure
requirements  that must be followed in  the specific
product evaluations. The contaminant-specific
protocols cover technologies that inactivate or
physically remove microbiological contaminants;
particulate material; reduce precursors to disinfection
by-products; reduce arsenic, nitrate, organic, and
inorganic chemicals; and radionuclides.  The test
plans and protocols may be used by utilities, state
drinking water agencies, and others interested in
evaluating technologies. If the testing is coordinated
with NSF and its partners, the EPA and independent
ETV-qualified field testing organizations, the manu-
facturer will receive ETV report documents present-
ing the testing results.

ETV Outputs
The ETV DWS Center has conducted equipment
evaluations involving several types of technologies:
•    UV and ozone inactivation of microbiological
     contaminants
•    Microfiltration and ultrafiltration membranes for
     microbial control
•    Coagulation/filtration package systems for
     arsenic and microbials
•    Nanofiltration membranes for DBP  control
•    Reverse osmosis for arsenic removal
•    On-site sodium hypochlorite generation for
     disinfection
•    Bag and cartridge filters for microbial control
•    Diatomaceous earth filter systems for microbial
     control

Information about ETV activities,  copies of ETV
reports, test plan/protocol documents, and mailing
lists may be obtained at the ETV web site,
www.epa.gov/etv/.
                                                                                                         53

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     Small Drinking Water Systems Handbook
54

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                                           Small Drinking Water Systems Handbook
11.0  Additional  Information  Sources
For more information about small PWSs, funding resources, agency contacts, and other water system related
topics mentioned in this document, please contact the following agencies or groups for assistance:

Federal  resources
Resource
Occupational Safety & Health Administration
U.S. Army Corps of Engineers
U.S. Geological Survey
U.S. Dept. of Agriculture
Rural Utilities Service
U.S. Environmental Protection Agency (EPA)
U.S. EPA Office of Groundwater and Drinking Water
U.S. EPA Office of Research and Development
U.S. EPA OGWDW - Public Drinking Water Systems
U.S. EPA OGWDW - Small Systems
U.S. EPA Region 1 (includes: Connecticut, Maine,
Massachusetts, New Hampshire, Rhode Island,
Vermont)
U.S. EPA Region 2 (includes: New Jersey, New York,
Puerto Rico, Virgin Islands)
U.S. EPA Region 3 (includes: Delaware, Maryland,
Pennsylvania, Virginia, West Virginia, Washington DC)
U.S. EPA Region 4 (includes: Alabama, Florida,
Georgia, Kentucky, Mississippi, North Carolina, South
Carolina, Tennessee)
U.S. EPA Region 5 (includes: Illinois, Indiana,
Michigan, Minnesota, Ohio, Wisconsin)
U.S. EPA Region 6 (includes: Arkansas, Louisiana,
New Mexico, Oklahoma, Texas)
U.S. EPA Region 7 (includes: Iowa, Kansas, Missouri,
Nebraska)
Contact
Web Link: www.osha.gov
Phone: (202) 761-0008
441 G. Street, NW
Washington, DC 20314
Web Link: www.usace.army.mil
Phone: (888) 275-8747
Web Link: www.usgs.gov
Phone: (202) 720-9583
1400 Independence Ave, SW
Washington, DC 20250
Web Link: www.rurdev.usda.gov/rus/index.html
Web Link: www.epa.gov
Phone: (202) 260-5543
Ariel Rios Building
1200 Pennsylvania Avenue, NW
Washington, DC 20460
Web Link: www.epa.gov/OGWDW/
Web Link: www.epa.gov/ORD/
Web Link: www.epa.gov/safewater/pws/pwss.html
Web Link: www.epa.gov/safewater/smallsys.html
Phone: (888) 372-7341 (61 7) 918-11111
Congress St., Suite 1100
Boston, MA 021 14
Web Link: www.epa.gov/region01/
Phone: (212) 637-3000
290 Broadway
New York, NY 10007
Web Link: www.epa.gov/region02/
Phone: (215) 814-5000
1 650 Arch Street
Philadelphia, PA 191 03
Web Link: www.epa.gov/region03/
Phone: (404) 562-9900
61 Forsyth Street, SW
Atlanta, GA 30303
Web Link: www.epa.gov/region04/
Phone: (312) 353-2000
77 West Jackson Blvd.
Chicago, IL 60604
Web Link: www.epa.gov/region05/
Phone: (214) 665-6444
Fountain Place 12th Floor, Suite 1200
1 445 Ross Avenue
Dallas, TX 75202
Web Link: www.epa.gov/region06/
Phone: (913) 551-7000
726 Minnesota Avenue
Kansas City, KS 66101
Web Link: www.epa.gov/region07/
                                                                            55

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     Small Drinking Water Systems Handbook
Resource
U.S. EPA Region 8 (includes: Colorado, Montana,
North Dakota, South Dakota, Utah, Wyoming)
U.S. EPA Region 9 (includes: Arizona, California,
Hawaii, Nevada and Pacific Islands & Tribal Nations
subject to U.S. law)
U.S. EPA Region 10 (includes: Alaska, Idaho, Oregon,
Washington)
Contact
Phone: (303) 312-6312
999- 18th St., Suite 300
Denver, CO 80202
Web Link: www.epa.gov/region08/
Phone: (415)744-1500
75 Hawthorne
San Francisco, CA 94105
Web Link: www.epa.gov/region09/
Phone: (206) 553-1200
1 200 6th Avenue
Seattle, WA98101
Web Link: www.epa.gov/region10/
     State resources
Resource
Alabama
Water Supply Branch
Dept. of Environmental Management
Alaska
Drinking Water and Wastewater Program
Dept. of Environmental Conservation
Div. of Environmental Health
American Samoa
American Samoa Environmental Protection Agency
Arizona
Drinking Water Monitoring and Assessment Section
Water Quality Division
Dept. of Environmental Quality
Arkansas
Div. of Engineering
Dept. of Health
California Dept. of Health Services
Div. of Drinking Water and Environmental
Management
Colorado
Drinking Water Program
Dept. of Public Health & Environment
WQCD-DW-B2
Connecticut
Water Supplies Section
Dept. of Public Health MS-51WAT
Delaware
Div. of Public Health
Delaware Health & Social Services
Florida
Drinking Water Section
Dept. of Environmental Protection
Georgia
Water Resources Branch
Environmental Protection Div.
Dept. of National Resources
Contact
Phone: (334) 271-7773
RO. Box 301 463
1400 Coliseum Blvd.
Montgomery, AL 36130-1463
Web Link: www.adem.state.al.us/EnviroProtect/Water/water.htm
Phone: (907) 269-7500
555 Cordova St.
Anchorage, AK 99501
Web Link: www.state.ak.us/dec/deh/safewater.htm
Phone: (684) 633-2304
Office of the Governor
Pago Pago, AS 96799
Web Link: www.epa.gov/region09/cross_pr/islands/samoa.html
Phone: (602) 207-4644
Room 200
3033 N. Central Ave.
Phoenix, AZ 85012-2809
Web Link: www.adeq. state. az.us/environ/water/dw/index. html
Phone: (501) 661-2623
4815 W Markham St. Mail Slot 37
Little Rock, AR 72205-3867
Web Link: www.healthyarkansas.com/eng/index.html
Phone: (916)323-6111
Web Link: www.dhs.cahwnet.gov/ps/ddwem/index.htm
Phone: (303) 692-3500
4300 Cherry Creek Dr. S.
Denver, CO 80246-1 530
Web Link: www.cdphe. state. co.us/wq/wqhom. asp
Phone: (860) 509-7333
RO. Box 340308
Hartford, CT 061 34-0308
Web Link: www.state.ct.us/dph/BRS/WSS/water_supplies.htm
Phone: (302) 739-5410
Blue Hen Corporate Center
655 Bay Rd. Dover, DE 19901
Web Link: www.state.de. us/dhss/dph/index. htm
Phone: (850) 487-1762
Twin Towers Office Building
2600 Blair Stone Rd.Tallahassee, FL 32399-2400
Web Link: www.dep.state.fl.us/water/default.htm
Phone: (404) 656-5660
Floyd Towers E, Rm. 1362
205 Butler St., SE
Atlanta, GA 30334
Web Link: www.georgianet.org/dnr/environ
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Small Drinking Water Systems Handbook
Resource
Guam
Guam Environmental Protection Agency
Hawaii
Environmental Management Div.
Hawaii Dept. of Health
Idaho
Div. of Environmental Quality
Illinois
Div. of Public Water Supplies
Illinois Environmental Protection Agency
Indiana
Drinking Water Branch
Office of Water Quality
Dept. of Environmental Management
Iowa
Water Quality Bureau
Iowa Dept. of Natural Resources
Kansas
Public Water Supply Section
Bureau of Water
Kansas Dept. of Health & Environment
Kentucky
Drinking Water Branch
Div. of Water
Dept. for Environmental Protection
Louisiana
Div. of Environmental Health Services
Louisiana Dept. of Health & Hospitals
Office of Public Health
Maine
Div. of Health Engineering
Maine Dept. of Human Services
Maryland
Public Drinking Water Program
Dept. of the Environment
Massachusetts
Drinking Water Program
Dept. of Environmental Protection
Michigan
Drinking Water & Radiological Protection Div.Michigan
Dept. of Environmental Quality
Minnesota
Drinking Water Protection Section
Dept. of Health
Contact
Phone: (671) 475-1658
Government of Guam
RO. Box 22439 GMF
Barrigada, GU 96921
Web Link: www.admin.gov.gu/doa/GOVGUAMID/GEPA-ID_1.html
Phone: (808) 586-4258
RO. Box 3378
Honolulu, HI 96801
Web Link: www.hawaii.gov/health/eh/sdwb/
Phone: (208) 373-0502
1410 N. Hilton
Boise, ID 83706
Web Link: www2. state. id. us/deq//water/water1. htm
Phone: (217) 785-8653
RO. Box 19276
Springfield, IL 62794-9276
Web Link: www.epa.state.il.us
Phone: (317) 308-3281
RO. Box 601 5
Indianapolis, IN 46206-6015
Web Link: www.state.in.us/idem/owm/dwb/index.html
Phone: (515) 725-0275
401 SW 7th St., Suite "M"
900 E. Grant St.
Des Moines, IA 50309
Web Link:
www.state.ia. us/go vernment/dnr/organiza/epd/wtrsuply/wtrsup. htm
Phone: (785) 296-5514
1000 SW Jackson, Suite 420
Topeka, KS 66620
Web Link: www.kdhe.state.ks.us/water/pwss.html
Phone: (502) 564-3410
14 Reilly Rd.
Frankfort Office Park
Frankfort, KY 40601
Web Link: http://water.nr.state.ky.us/dw/
Phone: (225) 765-5038
6867 Blue Bonnet Blvd.
Baton Rouge, LA 70810
Web Link: www.dhh. state. la. us/OPH/safewtr.htm
Phone: (207) 287-2070
101 State House Station
Augusta, ME 04333
Web Link: http://janus.state.me.us/dhs/eng/water/index.htm
Phone: (410) 631-3702
Point Breeze Bldg. 40, Rm. 8L
2500 Broening Hwy.
Baltimore, MD 21224
Web Link: www.mde.state.md.us
Phone: (617) 292-5770
One Winter St., 6th Floor
Boston, MA 021 08
Web Link: www.state.ma.us/dep/brp/dws/dwshome.htm
Phone: (517) 335-9218
Box 30630
Lansing, Ml 48909-8130
Web Link: www.deq. state. mi. us/dwr
Phone: (651) 215-0770
121 E. Seventh Place
RO. Box 64975
St. Paul, MN 55164-0975
Web Link: www.health.state.mn.us/divs/eh/eh.html
                                     57

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       Small  Drinking Water Systems Handbook
                            Resource
                          Contact
        Mississippi
        Div. of Water Supply
        Dept. of Health
Phone: (601) 576-7518
RO. Box 1700
2324 N. State Street
Jackson, MS 39215-1700
Web Link: www.msdh.state.ms.us/watersupply/index.htm
        Missouri
        Public Drinking Water Program
        Div. of Environmental Quality
        Dept. of Natural Resources
Phone: (573) 751-5331
RO. Box 176
Jefferson City, MO 65101
Web Link: www.dnr.state.mo.us/deq/pdwp/homepdwp.htm
        Montana
        Public Water Supply Section
        Dept. of Environmental Quality
Phone: (406) 444-4323
Box 2000901
1520 E. Sixth Ave.
Helena, MT 59620-0901
Web Link: www.deq.state.mt.us/wqinfo/index.asp
        Nebraska
        Nebraska Dept. of HHS Regulation & Licensure
Phone: (402) 471-2541
301 Centennial Mall South
RO. Box 95007, 3rd Floor
Lincoln, NE 68509-5007
Web Link: www.hhs.state.ne.us/
        Nevada
        Bureau of Health Protection Services
        Dept. of Human Resources
Phone: (775) 687-4750
1179 Fairview Drive, Suite 101
Carson City, NV 89701-5405
Web Link: www.health2k.state.nv.us
        New Hampshire
        Water Supply Engineering Bureau
        Dept. of Environmental Services
Phone: (603) 271-3139
RO. Box 956 Hazen Drive
Concord, NH 03302-0095
Web Link: http://www.des.state.nh.us/wseb/
        New Jersey
        Bureau of Safe Drinking Water
        Environmental Regulation
        Dept. of Environmental Protection
Phone: (609) 292-5550
RO. Box CN-426
Trenton, NJ 08625
Web Link: www.state.nj.us/dep/watersupply/
        New Mexico
        Drinking Water Bureau
        New Mexico Environment Dept.
Phone: (505) 827-7536 (877) 654-8720
525 Camino de los Marquez, Suite 4
Santa Fe, NM 87501
Web Link: www.nmenv.state.nm.us/dwb/dwbtop.html
        New York
        Bureau of Public Water Supply Protection
        Dept. of Health
Phone: (518) 402-7650
547 River Street
Troy, NY 12180-7650
Web Link: www.health.state.ny.us/nysdoh/water/main.htm
        North Carolina
        Public Water Supply Section
        Dept. of Env. and Natural Resources
Phone: (919) 733-2321
Box 29536
1634 Mail Service Center
Raleigh, NC 27699-1634
Web Link: www.deh.enr.state.nc.us/pws/index.htm
        North Dakota
        Div. of Municipal Facilities
        North Dakota Dept. of Health
Phone: (701) 328-5211
1200 Missouri Avenue, Room 203
RO. Box 5520
Bismark, ND 58506-5520
Web Link: www.ehs.health.state.nd.us/ndhd/environ/mf/index.htm
        Northern Mariana Islands
        Div. of Environmental Quality
        Commonwealth of the Northern Mariana Islands
Phone: (670) 664-8500
RO. Box 1304
Saipan, MP 96950
Web Link:  NA
        Ohio
        Div. of Drinking & Ground Water
        Ohio Environmental Protection Agency
Phone: (614) 644-2769
Lazarus Government Center
RO. Box 1049
Columbus, OH 43216-1049
Web Link: www.epa.state.oh.us/ddagw/
        Oklahoma
        Water Quality Div.
        Dept. of Environmental Quality
Phone: (405) 271-4000
1000 Northeast 10th St.
Oklahoma City, OK 73101-1212
Web Link: www.deq.state.ok.us/water.html
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                                                                Small Drinking Water Systems Handbook
                    Resource
                          Contact
Oregon
Drinking Water Program
Dept. of Human Resources
Phone: (503) 731-4317
RO. Box 14450
Portland, OR 97293-0450
Web Link: www.ohd.hr.state.or.us/dwp/welcome.htm
Pennsylvania
Bureau of Water Supply Management
Dept. of Environmental Protection
Phone: (717) 787-9037
RO. Box 8467
Harrisburg, PA 17105-8467
Web Link:
www.dep.state.pa.us/dep/deputate/watermgt/wmw/wmw.htm
Puerto Rico
Public Water Supply Supervision Program
Dept. of Health
Phone: (787) 754-6010
RO. Box 70184
San Juan, PR 00936
Web Link: www.epa.gov/region02/cepd/compnum.htm#JCA
Rhode Island
Office of Drinking Water Quality
Dept. of Health
Phone: (401) 222-6867
3 Capitol Hill, Rm. 209
Providence, Rl 02911
Web Link: www.health.state.ri.us/environment/dwq.htm
South Carolina
Bureau of Water
Dept. of Health & Environmental Control
Phone: (803) 734-5300
2600 Bull Street
Columbia, SC 29201
Web Link: www.scdhec.net/water/html/dwater.html
South Dakota
Drinking Water Program
Div. of Environmental Regulation
Dept. of Environmental & Natural Resources
Phone: (605) 773-3754
523 East Capital Ave.
Joe Foss Building
Pierre, SD 57501
Web Link: www.state.sd.us/denr/des/drinking/dwprg.htm
Tennessee
Div. of Water Supply
Dept. of Environment & Conservation
Phone: (615) 532-0191
401 Church Street
L&C Tower, 6th Floor
Nashville, TN 37243
Web Link: www.state.tn.us/environment/dws/index.html
Texas
Water Utilities Div.
Texas Natural Resource Conservation Commission
Phone: (512) 239-6096
RO. Box 13087
Austin, TX 78711
Web Link:
www.tnrcc.state.tx.us/permitting/waterperm/pdwOOO.html
Utah
Div. of Drinking Water
Dept. of Environmental Quality
Phone: (801) 536-4200
RO. Box 144830
Salt Lake City, UT84118
Web Link: www.deq.state.ut.us/eqdw/
Vermont
Water Supply Div.
Dept. of Environmental Conservation
Phone: (802) 241-3400
Old Pantry Bldg
103 South Main Street
Waterbury, VT 05671
Web Link: www.anr.state.vt.us/dec/watersup/wsd.htm
Virgin Islands
Div. of Environmental Protection
Dept. of Planning & Natural Resources
Phone: (340) 774-3320
Wheatley Center 2
St. Thomas, VI 00802
Web Link:  NA
Virginia
Div. of Water Supply Engineering
Dept. of Health
Phone: (804) 786-5566
Room 109-31
1500 East Main Street
Richmond, VA23219
Web Link: www.vdh.state.va.us/owp/water_supply.htm
Washington
Drinking Water Div.
Dept. of Health
Phone: (360) 236-3100 (800) 521-0323
Washington Industrial Center,  Building 3
RO. Box 47822
Olympia, WA 98504
Web Link: http://www.doh.wa.gov/ehp/dw/
Washington, DC
Environmental Health Administration
Phone: (202) 535-2500
51 N Street, NE
Washington, DC 20002
Web Link: www.dchealth.com/eha/welcome.htm
                                                                                                                  59

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     Small Drinking Water Systems Handbook
Resource
West Virginia
Environmental Engineering Div.
Office of Environmental Health Services
Bureau for Public Health
Wisconsin
Drinking Water & Groundwater
Wisconsin Dept. of Natural Resources
Wyoming
Wyoming Drinking Water Program
EPA Region VIII
Contact
Phone: (304) 558-2981
815 Quarrier Street, Suite 401
Charleston, WV 25301
Web Link: www.wvdhhr.org/bph/enviro.htm
Phone: (608) 266-2299
RO. Box 7921
Madison, Wl 53703
Web Link: www.dnr.state.wi.us/org/water/dwg/
Phone: (307) 777-7781
1 22 W 25th Street
Herschler Building
Cheyenne, WY 82002
Web Link: http://deq.state.wy.us/wqd.htm
     Other resources
Resource
American Public Works Association
American Water Works Association
American Water Works Association
Small Utility Network
Association of State Drinking Water Administrators
National Drinking Water Clearinghouse
National Environmental Services Center
National Rural Water Association
National Small Flows Clearinghouse
NSF International
Rural Community Assistance Corporation
Rural Community Assistance Program
Safe Drinking Water Foundation
Contact
Phone: (816) 472-6100
2345 Grand Blvd., Suite 500
Kansas City, MO 64108-2641
Web Link: www.apwa.net
Phone: (303) 794-7711
6666 W. Quincy Avenue
Denver, CO 80235
Web Link: www.awwa.org
Phone: (800) 366-0107
Web Link: www.awwa.org/sun/sunhome.htm
Phone: (202) 293-7655
1025 Connecticut Ave., NW Suite 903
Washington, D.C., 20036
Web Link: www.asdwa.org
Phone: (800) 624-8301 (304) 293-4191
West Virginia University
RO. Box 6064
Morgantown, WV 26506
Web Link: www.ndwc.wvu.edu AND www.nesc.wvu.edu
Phone: (580) 252-0629
291 5 South 1 3th Street
Duncan, OK 73533-9086
Web Link: www.nrwa.org
Web Link: www.nesc.wvu.edu
Phone: (734) 769-8010, (800) NSF-MARK
PO Box 1301 40
789 N. Dixboro Road
Ann Arbor, Ml 48113-0140
Web Link: http://www.nsf.org/water.html
Phone: (916) 376-0507
3120 Freeboard Dr. Suite 201
West Sacramento, CA 95691
Web Link: http://www.rcac.org/
Phone: (202) 408-1273
1522 K Street, NW, Suite 400
Washington, DC 20005
Web Link: www.rcap.org
Phone: (306) 934-0389
11 Innovation Blvd.
Saskatoon, SK Canada, S7N 3H5
Web Link: www.safewater.org
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Small Drinking Water Systems Handbook
Resource
Universities Water Information Network
Water Quality Association
Contact
Phone: (618) 453-6026
UWIN 4436, Faner Hall
Southern Illinois University
Carbondale, IL 62901
Web Link: www.uwin.siu.edu/index
html
Phone: (630) 505-0160
4151 Naperville Road;
isle, IL 60532
Web Link: http://www.wqa.org/
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12.0   References
                                                         Small Drinking Water Systems Handbook
1.   Virginia Water Resources Research Center,
    (1996), A Guide to the National Drinking Water
    Standards and Private Water Systems,
    Blacksburg, Virginia.

2.   U.S. Environmental Protection Agency (1999),
    25 Years of the Safe Drinking Water Act: History
    and Trends.

3.   Geldreich, E. E., et al., "The Necessity of
    Controlling Bacterial Populations in Potable
    Waters - Bottled Water and Emergency Water
    Supplies," Journal American Water Works
    Association, Vol. 67, No.3, March 1975.

4.   Prince, R., "Water Purification: a basic
    overview," Pacific Mountain Network News,
    Rural Community Assistance Corporation, West
    Sacramento, CA. Vol. XIX, Number 4, July, 2001.

5.   U.S. Environmental Protection Agency
    (September 1998), Variance Technology Findings
    for Contaminants  Regulated Before 1996 (EPA
    815-R-98-003)

6.   Goodrich, J. A., "Innovative Technologies for
    Small Drinking Water Systems," presented at the
    Japan - U.S. Governmental Conference on
    Drinking Water Quality Management and
    Wastewater Control, Colorado  Springs, CO., July
    24-30, 1999.

7.   MacDonald, J. A., Zander, A. K., and Snoeyink,
    V L., "Improving  service to small communities."
    Journal American Water Works Association,
    89(1): 58-64, 1997.

8.   U.S. Environmental Protection Agency (July
    1999), Small System Regulatory Requirements
    Under the Safe Drinking Water Act as Amended,
    (EPA-R-99-011).

9.   Pollack, A. J., Chen, A. S. C., Haught, R. C.,
    Goodrich, J. A.; (1999), Options for Remote
    Monitoring and Control of Small Drinking Water
    Facilities, Battelle Press, Columbus, Ohio.

10. U.S. Environmental Protection Agency
    (September 1998), Small System Compliance
    Technology List for the Non-Microbial
    Contaminants Regulated Before 1996 (EPA-815-
    R-98-002).

11. U.S. Environmental Protection Agency
    (September 1998), Small System Compliance
    Technology List for the Surface Water Treatment
    Rule and Total Coliform Rule (EPA-815-R-98-
    001).
12. Craun, G., Goodrich, J. A., Lykins, B. W,
    Schwartz, E., "How to Select a Personal and
    Household Drinking Water Treatment System: A
    Guide to Peace Corps Personnel," June 2, 1997.

13. U.S. Environmental Protection Agency (April
    2001), Low-Pressure Membrane Filtration For
    Pathogen Removal: Application,
    Implementation, and Regulatory Issues (EPA-
    815-C-01-001).

14. Goodrich, J. A., Lykins, B. W, Haught, R. C. and
    Li, S. Y., "Bag Filtration for  Small Systems," in
    Providing Safe Drinking Water in Small Systems,
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15. Goodrich, J.A., Haught, R.C., (2000) Controlling
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16. Jacangelo, J. G., Adham, S.,  and Laine, J. M.,
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17. Li, S. Y., Cryptosporidium potential surrogate
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    Master's thesis, Miami University, Oxford, Ohio,
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18. U.S. Environmental Protection Agency (1989),
    40 CFR Parts 141 and 142; Drinking Water;
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    Bacteria; Final Rule, Federal Register, 54(124),
    27486-27541, June 19, 1989.

19. Lykins, B.W, Goodrich, J.A., and Hoff, J.C.,
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20. U.S. Environmental Protection Agency (1994),
    40 CFR Parts 141, and 142; National Primary
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    Federal Register,  59(145), 38832-38858, July 29,
    1994.
                                                                                                     63

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      Small Drinking Water Systems Handbook


      21.  Clark, R. M., Goodrich, J. A., and Lykins Jr., B.
           W., "Package Plants for Small Water Supplies B
           The U.S. Experience." Journal of Water Supply
           Research Technology 43(1): 23-34, 1994.

      22.  Gordon, G., Gauw, R., Walters, B., Goodrich, J.
           A., Krishnan, R. A., and Bubnis, B., "Chemical
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           and Exposition, Chicago, ILL, June, 1999.

      23.  Standard Methods for the Examination of Water
           and Wastewater, 20th Edition, Published by
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      24.  Vel Leitner, N.K., Papailhou, A.L., Croue, J.R,
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           Hydrogen Peroxide." Ozone Science and
           Engineering, Vol. 16, pp 41-44.  1994.

      25.  Liang, S., et. al., "Oxidantion of MTBE by
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           Issue 6, pp 104-114, June 1999.

      26.  Lykins, B. W., Clark, R. M., Goodrich, J. A.;
           (1992), Point-of-Use/Point-of-Entry for Drinking
           Water Treatment, Lewis Publishers, Ann Arbor,
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      27.  Goodrich, J.A., Adams, J.O., Lykins, B.W, and
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           Systems and Treatment Options." Journal
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      28.  Lykins, B.W., Astle, R., Schlafer, J.L., and
           Shanaghan, RE., "Reducing Fluoride by
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           Water Works Association, November, 1995, pp
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      29.  Lykins, B. W., Goodrich, J.A., Clark, R.M., and
           Harrison, J., "Point-of-Use/Point-of-Entry
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      30.  Goodrich, J. A., Lykins, Jr., B. W, and Gordon,
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      31.  Haught, R. C., "The Use of Remote Telemetry to
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32. Haught, R. C., and Panguluri, S., "Innovations
    for Management of Remote Telemetry Systems
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33. National Drinking Water Clearinghouse (Spring
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34. Campbell, S., Lykins, B. W, Goodrich, J. A.,
    "Financing Assistance Available for Small
    Public Water Systems."  (EPA/600/J-93/270).
64

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              ACKNOWLEDGEMENTS

The contributors  and reviewers include James Goodrich
(EPA), Roy Haught (EPA), Eric Bissonette (EPA), Chuck
Guion  (EPA), Srinivas Panguluri (IT), Rajib Sinha (IT),
Sylvana Li (formerly with IT) and Harriet Emerson (NESC).
The authors would also like to thank everyone involved in
conducting the research at the EPA Test & Evaluation Fa-
cility and at other field locations.

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