United States
                   Environmental Protection
                   Agency
 Water Engineering
 Research Laboratory
 Cincinnati OH 45268
                   Research and Development
 EPA/600/S2-85/112 Jan. 1986
SER&         Project  Summary
                   Point-Of-Use Treatment  to
                   Control  Organic  and  Inorganic
                   Contaminants  in  Drinking
                   Water

                   Gordon E. Bellen, Marc Anderson, and Randy A. Gottler
                    Several communities using point-of-
                   use (POU) treatment technology for
                   drinking water contaminant removal
                   were studied under a cooperative
                   agreement between the U.S. Environ-
                   mental Protection Agency (EPA) and
                   the National Sanitation Foundation
                   (NSF). Study sites included communi-
                   ties in Pennsylvania and New Jersey
                   using POU activated carbon devices for
                   reduction of volatile halogenated or-
                   ganics; Arizona and Illinois communi-
                   ties using  POU activated alumina
                   devices for fluoride reduction;  and an
                   Illinois community using POU  reverse
                   osmosis devices for fluoride and dis-
                   solved solids reduction. In addition,
                   central treatment with activated alu-
                   mina for fluoride reduction was evalu-
                   ated at two operating plants in Arizona.
                    At all locations, POU devices pro-
                   vided effective treatment for  several
                   months of  operation. Average esti-
                   mated monthly costs per site for pur-
                   chase, installation, and maintenance of
                   treatment devices ranged from $4.25 to
                   $6.23 for activated  alumina and  acti-
                   vated carbon treatment, and were
                   $12.48 for reverse osmosis. Although
                   most POU installations operated with-
                   out problems from the time of installa-
                   tion, a few devices required unplanned
                   service. Management of POU devices is
                   necessary to ensure ongoing, effective
                   treatment.
                    This Project Summary was devel-
                   oped by EPA's Water Engineering Re-
                   search Laboratory, Cincinnati,  OH, to
                   announce key findings  of research
                   projects that are fully documented in
 three separate reports: "Defluoridation
 of Drinking Water in Small Communi-
 ties" {EPA/600/2-85/110). "Point-Of-Use
 Reduction of Volatile Halogenated
 Organics in Drinking Water" (EPA/600/
 2-85/109), and "Management of Point-
 Of-Use Drinking Water Treatment Sys-
 tems" (EPA/600/2-85/111} (see Project
 Report ordering information at back).

 Introduction
  Small  communities with contami-
 nated drinking water supplies often lack
 the financial resources and technical ex-
 pertise to effectively deal with the prob-
 lem. High initial capital costs can pro-
 hibit construction of a central treatment
 system for contaminant removal in
 many cases. Constructing a new well or
 connecting to a neighboring water sup-
 ply may not be feasible. One alternative
 solution is treatment of contaminated
 water at the point-of-use (POU).
  Although POU treatment may present
 an efficient, cost effective solution to
 drinking water contamination, there
 may be potential problems associated
with losing the level of control associ-
ated with central treatment systems.
When POU treatment is the selected al-
ternative, a sound program for manage-
ment of POU drinking water treatment
systems is necessary to ensure that all
sites receive the desired quality of drink-
ing water.

 Procedures
  POU treatment was studied in several
communities by monitoring existing in-
stallations or by installing and monitor-

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»ti
 ing new devices. All POU study sites
 used a form of the line-bypass approach
 to treatment. Line-bypass devices are
 designed to treat only water intended
 for consumption. With  this approach,
 the cold water line is tapped to provide
 influent to a treatment device. A sepa-
 rate tap for treated water is provided at
 the sink.
   Site selection was based on commu-
 nity interest, quality of source water, lo-
 gistics for water sampling, and the ap-
 proach to treatment. POU devices were
 purchased from equipment  manufac-
 turers or distributors and installed by
 licensed plumbing contractors. Water
 sample collectors were selected and
 trained  by NSF. Collection,  preserva-
 tion,  and analysis of water samples
 were in accordance with prescribed EPA
 methods.

   Bacteriological quality of predevice
 and postdevice water was monitored at
 all POU sites  with Standard  Plate
 Counts  (SPCs) and coliform  enumera-
 tion. To simulate water that  would be
 consumed if the faucet  were  not al-
 lowed to run before water was drawn,
 samples were collected from unflushed,
 undisinfected taps.  For  comparative
 purposes, samples were collected from
 disinfected taps that were flushed for 2
 to 3 min. In some cases, samples were
 also  collected from taps that  were
 flushed for 1L.

   Cost information for  POU treatment
 in the Illinois and Pennsylvania commu-
 nities was based on actual cost data col-
 lected during the project. Cost data from
 other sites were supplied by equipment
 manufacturers  and/or  municipalities.
 Maintenance costs for POU devices
 were  calculated using  manufacturers'
 rated  service volumes and the average
 volume of treated water.
   In the Village of  Silverdale, PA, 49
 POU activated carbon (AC) devices, rep-
 resenting products from several manu-
 facturers, were installed and monitored
 for 14 months of operation for control of
 volatile organic chemicals (VOCs), most
 notably trichloroethylene (TCE) and tet-
 rachloroethylene (PCE). In the Lake
 Telemark subdivision  of Rockaway
 Township, NJ, the township health de-
 partment and a manufacturer of POU
 AC devices began a pilot demonstration
 in  1981  by  installing and monitoring
 devices in 12 homes with wells contam-
 inated with organics. Performance veri-
 fication and  review of  cost data were
 included in this study.
  Arizona communities using POU acti-
vated alumina (AA) devices for fluoride
reduction included Thunderbird Farms
and Papago Butte Ranches, where sepa-
rate  distribution  systems are provided
for irrigation and domestic water. A por-
tion  of the  domestic water is bypassed
and  treated with AA for potable uses.
Domestic water  boards for  both com-
munities provide installation, monitor-
ing,  and maintenance  of  treatment
devices. POU treatment with AA for ar-
senic and/or fluoride reduction was
studied at two Arizona institutions, the
Ruth Fisher Elementary School located
near Tonopah and the You  & I Trailer
Park located new Wintersburg.

  At the three Illinois project sites, the
public water systems are supplied  by
well water with high fluoride, alkalinity,
and  dissolved solids. Project demon-
strations included installation and mon-
itoring of 10 POU AA devices in Parkers-
burg and 40 POU AA devices in Bureau
Junction. In Emington, 47 low-pressure
POU reverse osmosis (RO) devices were
installed and monitored for 8 mo. These
sites were the first applications of POU
fluoride reduction at the community
level in Illinois.

  Central AA treatment plants, located
at Gila Bend and Palo Verde, AZ, pro-
vided  a basis for comparison of two
small, but different sized, central facili-
ties.  The Gila Bend plant has been oper-
ating since May 1978; the  Palo Verde
plant has been operating since Decem-
ber 1979. In addition, a pilot study was
performed in North Myrtle Beach, SC, to
estimate AA central treatment costs. A
•summary of all project sites appears in
Table 1.

Table 1.   Site Summary
Results and Discussion

Volatile Halogenated Organics
Reduction
  The major VOCs in Silverdale's water
supply were TCE and PCE. POU devices
reduced concentrations of these con-
taminants to nondetectable levels
(<0.001 mg/L) in 87 percent of the sam-
ples collected  over 14 mo.  The mean
volume treated during this period was
340 gal; maximum volume treated was
1130 gal.  Devices were still in operation
at the end of the study.
  Breakthrough, defined as detection of
the same VOC in consecutive post-
device samples from the  same site at
concentrations above  0.001  mg/L, did
not occur for any device for TCE or PCE
during 14 mo of  sampling.  However,
trace concentrations of VOCs were de-
tected intermittently in postdevice sam-
ples from each model type;  concentra-
tions were generally below 0.005 mg/L.
The most frequently measured  post-
device VOC was chloroform. Although
the mean influent chloroform concen-
tration was 12 times less than the mean
TCE concentration, chloroform may
break through before TCE. This is sup-
ported by isotherm data typical for acti-
vated carbon.
  The capital cost for POU  AC treatment
in Silverdale ($289) was an average cost
of purchasing devices from several
manufacturers (in quantity) and equip-
ping them  with product water meters.
Maintenance costs included an average
monthly  repair cost per site of $1.43.
Some POU devices required no mainte-
nance during  the study.
  In the Lake Telemark subdivision of
Rockaway Township,  12  POU AC
devices were installed on private well
Site
Gila Bend, AZ
Palo Verde, AZ
North Myrtle Beach, SC

Thunderbird Farms, AZ
Papago Butte, AZ
Ruth Fisher School, AZ
You & 1 Trailer Park, AZ

Parkersburg, IL
Bureau Junction, IL
Emington, IL

Silverdale, PA
Rockaway Township, NJ
Treatment
Approach
Central
Central
Central

POU
POU
POU
POU

POU
POU
POU

POU
POU
Treatment
Process
AA
AA
AA

AA
AA
AA
AA

AA
AA
RO

AC
AC
Application
Fluoride Reduction
Fluoride Reduction
Cost Estimate for
Fluoride Reduction
Fluoride Reduction
Fluoride Reduction
Fluoride Reduction
Fluoride & Arsenic
Reduction
Fluoride Reduction
Fluoride Reduction
Fluoride & Dissolved
Solids Reduction
Organics Reduction
Organics Reduction

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water supplies in October 1981. Only
one of 21 postdevice samples collected
from  October 1982 through  October
1983 contained detectable VOCs (0.004
mg/L  TCE and 0.002  mg/L PCE). Eight
sites  were sampled  during the 24th
month of operation with no detectable
VOCs in effluent samples. After 2 yr of
service, the average cumulative volume
treated was approximately 1650 gal,
based on readings taken from a flow in-
dicator on the device. A device sampled
after  reaching its  estimated treatment
capacity  of 2000  gal produced water
with no detectable VOCs.
  Equipment costs of POU AC devices
in Rockaway ($225) were negotiated by
the community during an initial phase
of the pilot demonstration. No mainte-
nance was reported during the 2-yr pilot
demonstration period. A summary of
results from demonstrations of POU AC
devices in Silverdale and  Rockaway
Township appears in Table 2.
Activated Alumina
Defluoridation
  Several treatment runs from the AA
central treatment plants were evaluated
by collecting and analyzing water sam-
ples and by reviewing plant  records.
Fluoride exchange capacities ranged
between 1840 and 2600 grains/ft3 (4210-
5950 grams/m3) for Gila Bend and be-
tween  2260 and 3540 grains/ft3 (5170-
7890 grams/m3) for Palo Verde. Average
media  attrition rates per regeneration
were 1.2 percent of bed  volume for Gila
Bend and 2.8  percent for Palo Verde.
Most media attrition appeared to occur
during  regeneration.
  Although the plant  at Palo Verde
demonstrated higher fluoride exchange
capacity than  at Gila Bend, operating
costs were also higher. Central treat-
ment production costs (amortized capi-
tal costs plus operating  costs)  per 1000
gal were $0.45 for Gila Bend and $5.37
for Palo Verde. Higher chemical con-
sumption rates (i.e., stronger  regener-
ant) and very low production con-
tributed to  the higher cost. The use of
part-time, inexperienced operators at
Palo Verde  resulted in inefficient opera-
tion at  times.
  At North Myrtle Beach, a pilot demon-.
stration was  performed to develop a
cost estimate for construction and oper-
ation of central treatment facilities. Be-
cause North Myrtle Beach's water sup-
ply consists of 10 wells in dispersed
locations, the  proposed system was a
Table 2.    POU Activated Carbon Studies

Participating Sites
Service Area Type


Mean Treated Water Use (gpd)
Trichloroethylene (mean mg/L) 1
Predevice
Postdevice
1,1,1-Trichloroethane (mean mg/L)1
Predevice
Postdevice
Costs
Capital ($)2
To Customer ($/month)3
Silverdale, PA
49
central system
with single
family homes
1.0

0.080
<0.007

0.007
<0.007

289
5.98
Rockaway Township, NJ
12
private wells
at single
family homes
2.3 est.

0.125
<0.001

0.092
<0.007

255
4.23
^Samples containing <0.001 mg/L were assigned a value of 0.0009 mg/L for calculation of
 the mean.
2Average of five manufacturers; includes equipment + installation costs.
3Capital, amortized at 10% for 20 years + maintenance.
group of 10 small (200,000 gpd) central
plants. Estimated production costs were
$0.57 per 1000 gal.

  At Thunderbird Farms, several POU
AA devices  reduced influent fluoride
levels effectively for periods exceeding
2 yr. Other  AA  devices  operating at
Thunderbird Farms had shorter service
lives, attributed to  media cementing
and/or short-circuiting. At the You &  I
Trailer Park, raw water fluoride concen-
tration was 15.7 mg/L and arsenic was
0.086 mg/L. A POU AA device effectively
treated 2500 gal (330 bed volumes) be-
fore fluoride breakthrough, demonstrat-
ing the  highest exchange capacity
observed for POU devices (2300 grains/
ft3). Influent arsenic and silica concen-
trations  at Arizona POU sites generally
were reduced  to  nondetectable levels
beyond fluoride breakthrough.
  POU AA devices installed in Parkers-
burg and Bureau  Junction were
equipped with valves; this allowed par-
tial bypassing of raw water to provide
optimal  fluoride concentrations  by
blending treated and untreated water.
Valve settings  were controlled with a
colorimetric test  kit during sample col-
lection.
  The effect of raw water alkalinity is
demonstrated in the  data from Illinois
sites, which included a pilot demonstra-
tion in Emington. The higher alkalinity
at Parkersburg caused fluoride break-
through  at a lower mean cumulative
bed volume (110 bed volumes) than at
Emington (190 bed volumes). Break-
through at Bureau Junction, with the
lowest alkalinity, was not observed until
350 bed volumes. Part of the reduced
capacity at Emington must be attributed
to the accelerated flow (370 gpd) during
the pilot study.
  Maintenance costs for POU AA
devices were based on replacing the
alumina cartridge when treated water
fluoride levels reached the  local Maxi-
mum Contaminant Level (MCL). For Ari-
zona, the MCL was 1.4 mg/L, and for the
Illinois communities, it was  1.8-2.0 mg/
L. Summaries of results from Arizona
and  Illinois POU AA sites appear in
Table 3 and Table 4, respectively.

Low-Pressure Reverse  Osmosis
  POU RO systems installed in Eming-
ton used a spiral-wound polyamide RO
membrane operated at line pressure.
Pretreatment included granular acti-
vated carbon (GAC) followed by a 5-|A
prefilter. Product water was  stored in a
2-gal pressurized tank. Reject water was
bled through a capillary tube to the
home drain line. Product water from the
storage tank passed through a GAC pol-
isher before being dispensed.

  Fluoride rejection averaged 86 per-
cent, with total  dissolved solids rejec-
tion (TDS) averaging 79 percent. Rela-
tively large  ranges  of  rejection
percentages were observed  for all ana-
lytes. This phenomenon did not corre-
late with  site, use  rate, or collection
date, but appeared to be due in part to a
pressure  drop across the prefilter as-
sembly. Flow rates were measured for
several RO devices  during  a site visit.
Ranges of product and reject flow rates
were 1.3 to 4.4 gpd and 16.1 to 27.8 gpd,
respectively. Water temperatures and

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pressures (measured  at hose connec-
tions) did not correlate with flow rates.
Iron deposits in the well and distribution
system fouled some GAC prefilters, cre-
ating head loss across the pretreatment
assembly. One GAC prefilter which had
been fouled with iron deposits was  re-
moved, flushed, and reinstalled. The
resulting 33 percent production rate
increase was accompanied by a
29 percent increase  in solids  rejection,
implying a constant flux of solids across
the RO membrane, i.e., more water was
produced for essentially the same mass
of solids, resulting in higher  quality
water.
  The capital cost for POU RO  at Eming-
ton ($540) was an average of  several
manufacturers' quotes for devices, with
and without pressurizing pumps, based
on purchase of 40 to 50 units.  The aver-
age installation cost per unit of $68 (per-
formed by an equipment dealer) was in-
cluded.
  Costs for central RO treatment at Em-
ington were estimated by soliciting a
quote; they included approximately
$60,000 for a central RO system (includ-
ing mechanical and  electrical installa-
tion) and $60,000 for  a concrete block
building. Estimated operating costs per
1000  gal of product water  included
chemicals ($0.10),  power for  pumps
($0.36),  membrane  replacement every
5 yr ($0.18), and prefilter  cartridge  re-
placement ($0.02). Monthly  customer
costs were based on the design flow of
16,500 gpd. A summary of the  Emington
RO demonstration appears in Table  5.

Bacteriological Sample Results
  Standard  Plate Counts  (SPCs)  from
the AC sites indicated microbial  colo-
nization of the carbon bed. In Silverdale,
unflushed  postdevice samples had
mean densities two orders of magni-
tude higher than corresponding pre-
device samples. If  1L of water was
flushed from the line  before  sampling,
postdevice samples had mean densities
only one order of  magnitude higher
than predevice  samples. Samples of
water collected after 2 min of flushing
had SPC densities comparable to sam-
ples of water from the distribution sys-
tem. In Rockaway, flushing and disin-
fecting the  tap reduced  SPCs  by one
order of  magnitude. Data collected dur-
ing the study did not indicate coloniza-
tion of AC  devices by coliform orga-
nisms. Positive coliform results in
Silverdale were obtained from 4 of 176
postdevice samples collected  from
flushed,  disinfected taps. Postdevice re-
Table 3.    Arizona POU Activated Alumina Studies

Participating Sites
Service Area Type


Influent Fluoride (mg/L)
Influent Alkalinity (mg/L as CaCO3)
Mean Treated Water Use (gpd)
Volume to Breakthrough1
(gallons)
(bed volumes)
Costs
Capital ($)
To Customer ($/month)2
Thunderbird
Farms
8
central system
with single
family homes
2.6
200
1.4

>1540
>4W

225
4.44
Papago
Butte
1
subsystem
for several
families
2.6
200
18.5

9500
1270

350
4.60
Ruth Fisher
School
1
institution


4.4
80
8.5

WOO
270

360
12.00
You&l
Trailer Park
1
institution


75.7
40
5.5

2500
330

230
6.27
1 Defined as the point where postdevice fluoride concentration reached the local MCL.
2Capital, amortized at 10% for 20 years + maintenance.
Table 4. Illinois POU Activated Alumina Studies
Parkersburg
Participating Sites
Service Area Type


Influent Fluoride (mg/L)
Influent Alkalinity (mg/L as CaCO3)
Mean Treated Water Use (gpd)
Volume to Breakthrough1
(gallons)
(bed volumes)
Costs
Capital ($)
To Customer ($/month)2
10
central system
with single
family homes
6.6
1000
0.6

400
110

273
6.23
Bureau Junction
40
central system
with single
family homes
6.0
540
0.8

1300
350

285
4.25
Emington
1
pilot
study

4.5
880
370

700
190

273 est.
5.38 est.
1 Defined as the point where postdevice fluoride concentration reached the local MCL.
2Capital, amortized 10% for 20 years + maintenance.
Table 5.    Emington, Illinois, POU Reverse Osmosis Study

           Participating Sites
           Service Area Type
           Mean Treated Water Use (gpd)
           Mean Flow Rates (gpd)
             Product Water
             Reject Water
           Fluoride (mean mg/L)
             Predevice
             Postdevice
           Total Dissolved Solids (mean mg/L)
             Predevice
             Postdevice
           POU Treatment Costs
             Capital ($)1
             To Customer ($/month)2
           Estimated Central Treatment Costs
             Capital ($)
             To Customer ($/month)2
47
central system
 with single
 family homes
0.8

2.9
22.5

4.5
0.6

2530
520

540
12.48

122,000
28.80
1 Average of six manufacturers; includes equipment + installation costs.
2Capital, amortized at 10% for 20 years + maintenance.

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samples were negative for coliform or-
ganisms. No conforms were detected in
postdevice samples collected  in Rock-
away.
  Bacteriological samples collected at
AA POU sites indicated microbial colo-
nization of the alumina bed, though not
as great as with activated carbon. At the
Arizona sites, slight increases in  SPCs
through  AA devices  Were  observed.
Flushing reduced SPCs by a small mar-
gin. No coliforms were detected in Ari-
zona AA postdevice samples. In Bureau
Junction, postdevice SPCs were highest
when devices were first placed  in opera-
tion, and decreased with use. There was
no  evidence of colonization of AA
devices by coliform organisms. Out of
153 samples, coliforms were detected in
9 predevice samples and 4 postdevice
samples.  One  unit maintained consis-
tent positive coliform  results  and was
removed  from service. Resamples from
other units were negative for coliforms.
In Parkersburg, postdevice SPCs  were
highest when no influent chlorine resid-
ual was detected.  Flushing  and disin-
fecting taps reduced postdevice  SPCs
by an order of magnitude. No coliforms
were detected  in 80 Parkersburg  post-
device  samples.
  SPC results from Emington (RO & AC)
demonstrated an order of magnitude in-
crease  through the treatment system.
Limited sampling from stages in the RO
& AC system indicated that most bacte-
rial growth was occurring in the AC pol-
isher. Of 92 samples, coliforms  were de-
tected in 4 predevice and 11 postdevice
samples.  One site was resampled twice
before  postdevice samples were clear,
and another site required disinfection of
the RO system twice before resamples
were acceptable. Resamples from other
units were acceptable.
Summary and Conclusions
  Both central  and POU AA treatment
are effective in reducing fluoride levels
in otherwise potable water. POU treat-
ment with AA appears to be cost com-
petitive with central treatment  for com-
munities  having  330 to 710 service
connections. Raw water quality (i.e., al-
kalinity) and water comsumption deter-
mine the operational life of the POU AA
device  and have significant impact on
costs. Low-pressure POU RO treatment
was effective in reducing fluoride and
total dissolved solids  from a  brackish
groundwater supply. POU AC treatment
devices effectively reduced concentra-
tions  of  trichloroethylene, tetra-
chloroethylene, carbon tetrachloride,
1,1,1-trichloroethane, 1,1-dichloro-
ethylene, 1,1-dichloroethane, and chlo-
roform at influent concentrations
studied.

  Monitoring is required to ensure con-
sistent performance on a community
level. For AA devices, monitoring may
be  accomplished with field tests. For
VOC reduction in most cases, it is more
cost effective to replace AC cartridges
prematurely than to pay for frequent
analysis. For this method to be effective,
relatively consistent source water qual-
ity is required.
  Microorganisms, measured by the
standard plate count method, were
present  in higher  numbers in  post-
device water than in  predevice water.
Variation of sampling techniques for
collecting bacteriological samples from
POU devices significantly affected  re-
sults. Flushing taps can significantly im-
prove  bacteriological quality. The oc-
currence of coliforms in postdevice
samples appeared to be associated with
the bacteriological quality of the source
water.


Recommendations
  A sound program for management of
POU treatment  systems is necessary to
ensure that the desired level of treat-
ment is provided to all sites, that pre-
scribed monitoring and maintenance
are carried out, and that the system is in
compliance with applicable regulations.
This may be accomplished through for-
mation of a water quality district, an in-
dependent corporate body. The district
obtains funding, incurs costs,  and as-
sumes responsibility for the treatment
system. The district may resemble ex-
isting districts created for water supply,
wastewater discharge, or  solid waste
disposal. For POU treatment to be con-
sidered as a means of compliance with
regulations, regulatory agencies may
require the establishment  of a  clearly
defined body to assume responsibility
for  the system. Formation of  an offi-
cially sanctioned district may also open
avenues for funding not otherwise
available. The basic management func-
tions of a water quality district include
determination of the best treatment ap-
proach, equipment selection, coordina-
tion of equipment installation, monitor-
ing and  maintenance, district admin-
istration, and education and public noti-
fication.
  The full  reports were submitted  in
partial fulfillment of Cooperative Agree-
ment R809248 by the  National Sanita-
tion Foundation under the sponsorship
of the U.S.  Environmental Protection
Agency.
                                                                            U. S. GOVERNMENT PRINTING OFFICE: 1986/646-116/20762

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                                          Gordon E. Bellen, Marc Anderson, and Randy A. Cottier are with the National
                                            Sanitation Foundation, Ann Arbor, Ml 48106.
                                          Steven Hathaway is the EPA Project Officer (see below).
                                          This Project Summary covers three separate reports, entitled:
                                              "Point-of-Use Reduction of Volatile Halogenated Organics in  Drinking
                                              Water,"(Order No. PB 86-107 711/AS; Cost: $11.95)
                                              "Defluoridation of Drinking Water in Small Communities," (Order No. PB
                                              86-109 337/AS; Cost: $16.95)
                                              "Management of Point-of-Use Drinking Water Treatment Systems." (Order
                                              No. PB 86-105 285/AS; Cost: $11.95)
                                          The above reports will be available only from: (cost subject to change)
                                                 National Technical Information Service
                                                 5285 Port Royal Road
                                                 Springfield,  VA 22161
                                                 Telephone: 703-487-4650
                                          The EPA Project Officer can be contacted at:
                                                 Water Engineering Research Laboratory
                                                 U.S. Environmental Protection Agency
                                                 Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300

EPA/600/S2-85/112
             0000329   PS

             U  S  ENVIR  PROTECTION  AGENCY
             REGION 5 LI8R*RY
             230  S  DEARBORN  STREET
             CHICAGO               It   60604

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