EPA-600/2-82-101
December 1982
PERFORMANCE CHARACTERISTICS OF
PACKAGE WATER TREATMENT PLANTS
James M. Morand
Matthew J. Young
University of Cincinnati
Cincinnati, Ohio 45221
Cooperative Agreement No. CR806449
Project Officer
Thoraas J. Sorg
Municipal Environmental Research Laboratory
Drinking Water Research Division
Cincinnati, Ohio 45268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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This Page Intentionally Blank
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DISCLAIMER
The information in this document has been funded wholly or in part
by the United States Environmental Protection Agency under Cooperative
Agreement No. CR 806449 with the University of Cincinnati; it has been
subject to the Agency's peer and administrative review; and it has been
approved for publication. The contents reflect the views and policies of
the Agency. Mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
ii
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FOREWORD
The U.S. Environmental Protection Agency was created because of in-
creasing public and government concern about the dangers of pollution to the
health and welfare of the American people. Noxious air, foul water, and
spoiled land are tragic testimonies to the deterioration of our natural
environment. The complexity of that environment and the interplay of its
components require a concentrated and integrated attack, on the problem.
Research and development is that necessary first step in problem solu-
tion; it involves defining the problem, measuring its impact, and searching
for solutions. The Municipal Environmental Research Laboratory develops new
and improved technology and systems to prevent, treat, and manage wastewater
and solid and hazardous waste pollution discharges from municipal and com-
munity sources, to preserve and treat public drinking water supplies; and to
Minimize the adverse economic, social, health, and aesthetic effects of pollu-
tion. This publication is one o£ the products of that research, and provides
a most vital communication link between the researcher and the user community.
Many small communities in this country use prefabricated package water
treatment plant3 to treat surface waters to supply their drinking water. Six
plants were monitored intermittently over a period of 2 year3 to establish
their effectiveness in removing turbidity and bacteria.
Francis T. Mayo, Director
Municipal Environmental
Research Laboratory
iii
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ABSTRACT
This study was undertaken to collect reliable onsite information on the
quality of treated water produced by package plants.
Information concerning package plant installations in the U.S. was sought
via a questionnaire. Over five hundred installations supplying potable water
were identified through lists obtained from manufacturers and state agencies.
This total is not inclusive of all such plants as not all manufacturers or
states supplied lists of installations.
Six plants in operation year-around were selected to be representative of
those serving small populations and were monitored to assess their performance
and ability to supply water meeting the National Interim Primary Drinking Water
Regulations. All plants selected used surface water sources.
Site visits were made over a 2 year period. At each plant,grab samples
were collected of the raw water, treated water, and water from the dis-
tribution system. Turbidity, total coliform, and chlorine residual data were
collected on all visits. Standard plate counts, chemicals listed in the USEPA
Drinking Water Regulations, and trihalomethanes were determined intermittently.
Only one treated water sample, a distribution sample, showed any coliforns.
Sixty-eight percent of the treated water standard plate counts showed densities
of 10 or less per milliliter.
Three of the plants met the 1 ntu turbidity standard on nearly all
occasions. The other three plants were meeting the standard during less than
half of the sampling trips. Failure of these plants to perform well is attrib-
uted to the variability and quality of their sources and/or to the lack of
skilled operators having sufficient time to devote to treatment.
This report was submitted in fulfillment of Cooperative Agreement
CR806449 by the University of Cincinnati under the sponsorship of the U.S.
Environmental Protection Agency. This report covers the period December, 1978
to June, 1981 and work was completed as of October 17, 1981.
iv
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CONTENTS
Foreword . ill
Abstract . . , iv
Figures vl
Tables ..................... vii
Acknowledgments . ix
1. Introduction ..... ....... 1
2. Conclusions . . ............. 2
3. Background 4
Small Systems ... 4
Regulations ...... 5
Prevalence. . .............. 9
4. Design* 11
Unit Operations 11
Manufacturers ........... 15
5. Procedures. ......... 20
Field Procedures 20
Analytical Methods. . ...... 24
6. Case Studies. ......... ......... 27
Site V 29
Site I 35
Site V 41
Site R 50
Site ? 58
Site C 58
7. Summary ..... ......... 70
References ... ............. 72
v
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1
2
3
4
5
6
7
8
9
10
11
12
13
14
I2&
10
30
31
36
37
42
43
47
51
52
59
60
64
65
FIGURES
Number or potable water supply package plants
identified in the U.S
Site W facility layout
Site W Neptune Microfloc AQ40
Site T facility layout
Site T Neptune Microfloc AQ40
Site V facility layout
Site V Neptune Microfloc AQ40
Site V Turbidity Removal
Site R facility layout
Site R Neptune Microfloc AQ12
Site P facility layout
Site P Neptune Microfloc WB133
Site C facility layout
Site C Permutit 200 GR1
vi
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TABLES
Number Page
1 Water treatment design standards 6
2 Solids contact unit design standards 8
3 Facilities in study 22
4 Schedule of field trips 23
5 Analytical methods 25
6 Treatment process characteristics 23
7 Site W microbiological analysis and
water quality characteristics 32
8 Site W trihalomethane analysis 33
9 Site W chemical analyses performed by USEPA 34
10 Site T microbiological analysis and
water quality characteristics 38
11 Site T trihalomethane analysis 39
12 Site T chemical analyses performed by USEPA 40
13 Site V microbiological analysis and
water quality characteristics 44
14 Site V trihalomethane analysis 43
15 Site V chemical analyses performed by USEPA 49
16 Site R microbiological analysis and
water quality characteristics 53
17 Site R trihalomethane analysis 56
18 Site R chemical analyses performed by USEPA 57
19 Site P microbiological analysis and
water quality characteristics 61
vii
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Number Page
20 Site P trihalomethane analysis 62
21 Site P chemical analyses performed by USEPA 63
22 Site C microbiological analysis and
water quality characteristics 67
23 Site C trihalomethane analysis 68
24 Site C chemical analyses performed by USEPA 69
viii
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ACKNOWLEDGEMENTS
Appreciation is extended to Tom Sorg, Kim Fox, and Ray Taylor of the U.S.
Environmental Protection Agency for their cooperation and support throughout
the project.
Marie Kluesener is acknowledged for his help in obtaining state regula-
tions concerning package water treatment plants.
Numerous personnel at Neptune Microfloc, Inc., Permutit Co., Environmen-
tal Conditioners, Inc., Culligan USA, and National Technical Services, Inc.
were very helpful in receiving us at their headquarters and showing us their
manufacturing facilities.
Don Kunz, Calvin Beckelheimer, Jim Hodges, Clyde Hmigh, and Craig Cobb of
the West Virginia State Health Department, Division of Sanitary Engineering,
are thanked for allowing access to state laboratories and for other assistance
to the field work.
We also wish to acknowledge the assistance of personnel from the Univer-
sity of Cincinnati Civil and Environmental Engineering Department, Environmen-
tal Engineering Laboratory.
The operators and others associated with the water treatment plants
visited during this work contributed immensely through their cooperation.
ix
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SECTION 1
INTRODUCTION
The problem of providing acceptable water supplies to the public is
particularly acute for small communities with limited financial resources and
limited availability of competent treatment plant operators. Recreational
areas in isolated locations also must provide acceptable drinking water to
their visitors and staff while confronted with the difficulty of attracting
personnel with experience and skill in water treatment. During the last 20
years, cost savings have been achieved in such situations by using package
water treatment plants. A package plant generally consists of prefabricated
and largely preassembled clarification and filtration units. These plants are
reputed to require minimal operational skill and to be a viable and economical
low-flow alternative to the custom-built facility. Six such plants serving
small populations were selected for study. These plants were monitored
to assess their performance and ability to supply water meeting the National
Interim Primary Drinking Water Regulations, particularly the turbidity and
microbiological requirements.
The design of a custom-built treatment plant should depend on an evalua-
tion of the nature and quality of the particular water to be treated. Package
plants are designed with the goal of producing a satisfactory quality of
treated water from a range of influent waters. Flow rates for plants on the
market range from 10 to 2100 gpm.
The financial and personnel limitations faced by small communities and
recreational areas can be alleviated by prefabricated plants of this type.
The question of the adequacy of treatment provided by these plants as they are
managed and operated by small communities and recreational areas is not ans-
wered by data available in the literature. This study was undertaken to
collect reliable onsite information on the quality of treated water produced
by package plants.
1
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SECTION 2
CONCLUSIONS
The package plant at Site V reduced the turbidities of more than 100 ntu
of the source water to less than 1.0 ntu. On one occassion, the influent
turbidity increased from L7 ntu to greater than 100 ntu within a 2 hour
period while the effluent turbidity remained less than 1.0 ntu. On earlier
occasions, prior to the performance of adequate maintenance, this plant did
not consistently reduce the turbidities of the influent level in the range
of 35 - 50 ntu to an acceptable level.
At Site R influent turbidities greatly in excess of 500 ntu were en-
countered and not successfully treated. Moreover, even with influent turbi-
dities of less than 30 ntu, the plant was not able to achieve an effluent
turbidity of leas than 1 ntu because of inadequate operator skill.
The maximun influent turbidity recorded at Site P was 17.2 ntu during
this study. Of 9 effluent samples measured at this plant, only 3 were
less than 1.0 ntu. This plant was in operation an average of 13.7 hours per
day and the operator was present no more than 2 hours per day.
The source waiters at plant Sites C and W had turbidities of less than
30 ntu. Operators at these locations were experienced and effluent
turbidities measured exceeded 1.0 ntu only once during this study.
The maximum influent turbidity measured during this study at Site T was
10.4 ntu. A pump failure and a distribution system problem that required
extensive operator attention caused effluent turbidities of 1.9 and 3.2 ntu
respectively. Otherwise, the maximum effluent turbidity was 1.1 ntu.
These specific findings lead to the following general conclusions regard-
ing applications of package plants.
Package water treatment plants manned by competent operators can readily
treat the turbidity and bacteria of surface waters of fairly consistent qua-
lity. Reservoirs have proven satisfactory for providing acceptable in-
fluent waters.
Package plants using variable sources, e.g., streams, require a high
degree of operational skill. A variable source necessitates near constant
vigilance of the package plant by the operators.
Regardless of their source quality, package plants require a certain
level of maintenance and operational skill. Lack of this minimal skill and
attention precludes consistent successful turbidity removal irrespective of
the influent quality.
2
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Most package plants are located in rural or remote areas where it may be
difficult to hire well trained operators. Small communities may have to
greatly increase salaries to attract well qualified operators.
3
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SECTION 3
BACKGROUND
SMALL SYSTEMS
Data available on the number of community water systems in the United
States vary depending on their source, A committee report to the American
Water Works Association indicates there are some 60,000 systems, of which more
than 90 percent serve populations smaller than 5,000, and 95 percent serve
less than 10,000 population (1). A U.S. Environmental Protection Agency draft
briefing document presented to the National Drinking Water Advisory Council
mentions some 59,000 systems, 87 percent of which serve populations under
2,500 (2). Most very small systems (populations under 500) are privately
owned, and about half serve mobile home parks. The EPA compilation does not
include Federal and Indian land systems. Approximately 1,000 of these are
included in the AWWA report. (Although most community systems are small, the
vast majority of the population is served by larger systems. The EPA document
states that 79 percent of the 213 million persons protected by the Safe
Drinking Water Act are served by large systems, i.e., systems serving more
than 10,000 population.)
EPA estimates that 11,300 community systems are out of compliance for
traditional contaminants in the Interim Primary Drinking Water Regulations. Of
this number, about 5400 fail to meet inorganic standards, about 700 fall short
of turbidity standards, and about 5200 do not meet bacteriological standards
(including about 600 who also fail to comply with turbidity or inorganics).
The AWWA interim report lists problems and weaknesses of small- and
medium-size water utilities as including, with various degrees of severity,
lack of qualified operators, knowledge limitations, and finances. The lack of
qualified operators i3 attributed to low salary, limitation in training oppor-
tunities, part-time positions, and limited upward mobility. The knowledge
limitations include operating and maintenance procedures and selection of
equipment and supplies.
Package water treatment plants are intended to alleviate some of these
problems. A package plant has been defined for this report as a prefabri-
cated, largely preassembled unit incorporating the conventional treatment
process of flocculation, sedimentation, and filtration. There are commer-
cially available treatment unit3 employing other processes, such as ion
exchange and reverse osmosis, for the removal of dissolved substances but
these types of treatment were not included in the scope of this work.
The focus of this work is on the problems confronting small communities
and recreational areas in providing safe drinking water to their customers.
4
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This size and type of facility does not normally have the financial resources
nor the access to skilled plant operators that might be found in a larger
community or industry. Conventional treatment processes meet the lower cost
and operational skill requirements that face small communities and recrea-
tional area operators.
Regulations
Information concerning regulations, restrictions or standards pertaining
to package treatment plants in the U.S. and the locations of such plants was
obtained by writing, during the winter of 1979, to the Health Department or
other appropriate agency in each of the fifty states and Puerto Rico as well
as to the Army Corps of Engineers. Replies were received from all except the
3tates of Nevada, New Jersey, Oregon and Tennessee. Information concerning
the locations of such plants was also obtained from the various manufacturers
of water treatment package plants.
None of the states that replied to the written inquiry prohibit directly
the use of prefabricated water treatment plants. Only a few have policies
designed specifically for thi3 type of plant. Many of the states follow the
'Recommended Standards for Water Works—Policies for the Review and Approval
of Plans and Specifications for Public Water Supplies' (3) usually referred to
as the 'Ten States Standards' established by the Great Lakes-Upper Mississippi
River Board of State Sanitary Engineers. The member states of the Board are:
Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, New York, Ohio, Penn-
sylvania and Wisconsin. The following states are not members of the Board,
but seem to have used the 'Tea States Standards' as a basis for their design
standards: Arkansas, Louisiana, Maine, Massachusetts, Nebraska, North Dakota,
South Dakota, Vermont, Washington, West Virginia and Wyoming. The 'Ten States
Standards' are design oriented and do not directly address finished water
quality.
The states of Alabama, Arizona, Georgia, Kansas, North Carolina, Oklahoma,
Texas, Utah and Virginia have set up public water systems rules and regula-
tions in a format similar to the 'Ten States Standards'. The specific design
details differ somewhat and those of concern for conventional treatment are
outlined for each of the nine above states in Table I.
The water supply regulations of Colorado, Connecticut, Hawaii, Idaho,
Mississippi, New Mexico and Rhode Island do not address plant design, but are
written as water quality standards specifying maximum contaminant levels,
analysis and sampling techniques, etc., that must be complied with. Of course,
the public water supply in any state is subject to the conditions prescribed
by the U.S. Environmental Protection Agency in the Safe Drinking Water Act and
the National Interim Primary Drinking Water Regulations.
Prefabricated water treatment plants do not generally meet the design
requirements given in the various states' regulations in the areas of deten-
tion times and filter rates. Design standards often are recommended standards
and it is the policy of the 'Ten States ' committee as well as many other
states, 'to encourage rather than to obstruct the development of new processes
and equipment.' Generally, approval for a new process may be given by a state
5
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TABLE 1
WATER TREft'IMEWr DESIGN STANQftRDS
(1978)
Itl
States
Al-A
ARIZ
CA
KAN
N CAK
l* LA
TfcXAS
UTAH
VIK
UAV10 M1K - detention
>30
>60
30-120
-
30
-
30-120
60-120
>30
> 10
(seconds)
ILUCOILATIOM - detent lou
>30
>10
20-60
>30
>20
30-60
>0-60
10-60
L,u
(•Jnutes)
"""
- flow vel.
0.5-1.5
0.5-1.5
-
-
-
-
0.8-2.0
-
>0.5
-
«!>•)
- paddle vel.
0.5-2.0
0.5-2.0
0.5-2.0
-
-
-
-
-
0.5-2.0
-
(fps)
- conduit vel.
0.5-1.5
<0.5
0.5-1.5
-
-
<0.5
0.5-1.0
-
0.5-1.5
<0.5
(fp«)
SfcOIHKNTATlON - detention
>4
>4
>4<"
4
j_4<2)
>4
>4
><<»
>4
(liuuiv)
IL 1
~~*
- overflow
-
<550
360-550
-
-
-
<600
-
-
360-5SU
(sp4/s<| ft)
- weir load
<20000 <20000
11500-20000
-
-
<2UHH)
<20000
-
<50000
-
-flow vel.
<0.5
<1
0.5-3.0
-
-
-
-
-
<3
< I
Uh»)
FILTRATION - rata
_
<4<»
2
5<5>
4(5)
2-3
<5
3-5<5>
<4<»
(|I«/M '*)
- aedla depth
24-30
27-30
24-30
-
-
24-30
36-48
24-30
24-30
< 2/-30
(Inches)
- water depth
> 36
>48
>36
-
-
-
-
-
>36
> Jb
(Incites)
"""
—
— Iiokwaxti
> 15
15-20
> I)
*
-
-
15-30
-
-
>15
UlVs* <*)
(1) My be reduced for liae-soda softening im (round waters
(2) depending 0*4 tuuico. 1.5-2.0 houra wliere tube icttUn allowed
(1) leae where tube settlers used
(4) 5SO-IOHO gpd/sq ft for line aoftenlng
(5) for sNiltlnedla filters
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i£ the prqcess has been thoroughly tested as a pilot scale and/or a full scale
plant for a period of time sufficient to indicate satisfactory performance.
Some states do have mandatory design standards which may effectively
prevent the use of certain types of package plants. An example is Georgia
where no package unit submitted to the state as of the date of this survey had
been able to meet the obligatory requirements of 4 hours detention time prior
to filtration and a maximum filtratioa rate of 2 gpm per square foot. The only
three prefabricated water treatment plants in Georgia in 19 79 were at Army
Corps of Engineers recreational sites.
Tube settlers aad mixed media filtration have been used in some package
plants. The 'Ten States Committee' states that sufficient experience is not
yet available to establish design standards for tube settlers and that pilot
or full scale studies may be required prior to approval. Three states - Utah,
Kansas, and Arizona - have specific design guidelines for tube settlers. If
mixed media filtration is used, several states will allow filter rates higher
than the traditional 2 gpm/sq ft.
The 'Ten States Standards' and various individual states specify design
standards for solids contact units. These are summarized in Table 2.
The 'Ten States Standards' and many of the other states' design standards
consider solids contact clarifiers acceptable for combining softening and
clarification where raw water characteristics are not variable and flow rates
are uniform. In most cases if solids contact units are to be used as clari-
fiers without softening, specific approval of the reviewing authority is
required.
No states that replied to the request for information had regulations
concerning direct filtration. The 'Ten States Standards' policy statement
regarding this method of treatment is as follows:
"Although direct filtration has been suggested as an alter-
nate method of complete treatment, sufficient experience is
not yet available to establish design standards.
Uhere the reviewing authority has determined that the direct
filtration process may be applicable, an engineering report,
whicji includes a historical summary of raw water quality
data with special reference to fluctuations in quality,
changing meteorological conditions, sources of contamina-
tion, etc., shall be submitted prior to a study proposal.
If the report is accepted, a study proposal shall be submit-
ted including the format for conducting a pilot plant and/or
full scale demonstration satisfactory to the reviewing
authority. Studies shall particularly emphasize:
1. Correlations between raw water quality and upset raw
water boundary conditions for the process with a deter-
mination of anticipated down time.
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TABLE 2 SOLIDS CONTACT UNIT DESIGN STANDARDS
f loc t imes
(uiiuutes)
detent ion
(hours)
weir load
(gpm/ft)
upflow rate
(gpm/sq ft)
10
States
_> 30
«<»
< 10(4)
< !<*>
ARIZ N. CAK OKLA
> 30 20
(1)
< 10(4) < 7
< 1<5> < 1
TEXAS
> 2
(2)
> 2
(4)
< 10
< 1.25
(6)
UTAH
VIR
> 30
> 2^ > 2^
< 10
(4)
< 1<7> < 1<5>
(1) for surface water
use 1 hour for ground water
(2) for clarification
>1.5 hours for softening
(3) for clarification
1 hour for softening
(4) for clarifiers
20 gpui/ft for softeners
(5) for clarifiers
1.75 gpui/sq ft for softeners
(6) for clarification
< 2.2 gpw/sq ft for softening
(7) for clarifiers
1.5-2.5 gpui/sq ft for softeners
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2. A determination of the quality and/or operational
parameters which serve as the best measure of treatment
3erve as the means of process control.
3. A determination of chemical feed rates under varying
raw water quality conditions necessary to optimize
finished water quality.
4. Alternate sources and/or modes of treatment to insure
reliability of service 100 percent of the time."
It is not permissible to treat surface water with direct filtration
package plants in Colorado and Kentucky since these states require complete
treatment for a surface source.
The majority of package plants are located in rural or remote areas.
Many are in parks, campgrounds, and other recreational areas. These are also
the areas where it may be most difficult to find well trained operators.
Package water treatment plants are reputed to require considerably less oper-
ator attention than conventional facilities although they cannot be merely
installed and then left to run by themselves. Of the forty-five states that
responded to the request for information, nineteen did so with a copy of their
water works or water supply regulations. Of these nineteen sets of regula-
tions, only seven contained a clause dealing with state operator certifica-
tion.
PREVALENCE
The number of package plant installations identified froa the responses
received from the individual states and from the manufacturers is compiled in
Figure 1. The list totals 518 and is not complete since not all* of the states
and manufacturers contacted, nor the Corps of Engineers, had a list of their
installations available to send.
The package plant sites are widely distributed across the U.S. with a
concentration in the Northwest where some of the largest manufacturers of this
type of plant are found. There is no apparent pattern of concentration of
plants caused by the type of standard adopted by various states. Rather, most
states seem to have considered the individual applications for the plants.
9
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Figure 1
NUMBER OF POTABLE WATER SUPPLY PACKAGE PLANTS IDENTIFIED IN US
(Winter 1979)
MASS 0
OHIO
Design St«mt«r«U
Quality
Design ¦>«i• M«t Repurted 1.
WMTO KIUI
16
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SECTION 4
DESIGN
UNIT OPERATIONS
The package plants observed in this study consisted of coagulation/
flocculation, clarification, and filtration units. Common methods of achiev-
ing these processes in package water treatment plants are summarized below.
Information on specific models on the market follows.
Rapid Mix
Methods used include mechanical mixers, baffled mixing, and in-line
mixing.
Mechanical mixers have the advantages of little head loss and varying
rotation speed to adjust for variations in raw water quality and/or coagula-
tion chemicals used. Design practices include less than 10 seconds detention
time as compared with 10-30 seconds as listed in Water Treatment Plant Design
(4) and 20 to more than 40 seconds depending upon the system velocity gradient
as suggested by Gemmell (5).
A summary by Amirtharajah (6) of the available literature on mechanical
mixers indicates:
a square vessel performs superior to a cylindrical vessel,
stator baffles provide improvement,
a flat-bladed impeller performs bettar than a fan or propeller
impeller,
chemicals introduced at agitator blade level enhance coagulation.
Vrale and Jorden (7) concluded the typical mechanical mixer is comparatively
inerticient.
Baffled mixing has the advantage of no mechanical equipment that must be
kept in repair or replaced. The lower power input in a gravitational system
indicates a longer detention time will be required to achieve adequate mixing.
Static in-line mixing is frequently found in package plants. Approxima-
tely 200 pipe diameters are required for adequate mixing for a smooth pipe
11
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with a Reynolds number of 10,000 if the source issues into the pipe at the
wall with no initial mixing (8). The mixing distance can be reduced if a
turbulent jet injects perpendicularly into the pipe wall because the injected
fluid is transported away from the wall and produces some initial mixing. Ger
and Holley (8) conclude a simple, single point of injection will not fulfill the
rapid mixing process requirements. Baffled pipe sections will increase the
turbulence thus reducing the distance required for adequate mixing. These
units are inflexible in that the turbulence cannot be varied.
The theoretical analysis of rapid mixing is not advanced and the litera-
ture on design recommendations is conflicting. As a consequence, the design
of rapid mix units is largely empirical.
Colloid agglomeration is probably by both adsorption and entrapment in
most water treatment situations. It is impossible to design a single rapid
mix unit that is optimum for every situation likely to be encountered in water
treatment. Amirtharajah (6) says the minimum of 30 seconds detention required
by many states does not meet either the need for the adsorption-destabiliza-
tion reactions nor the extended time for sweep coagulation and he concludes
that "based on present day theory, this seems to be an extremely poor recom-
mendation."
Flocculation
Design of flocculation tanks includes selection of a velocity gradient,
reactor shape, and detention time that will enable production of aggregates
that can be removed by the sedimentation process.
The size of the tank to achieve a desired level of particle aggregation
is determined by the rate at which the aggregation occurs. Compartmentali-
zation of the flocculation tank is reported by Argaman and Kaufman (9) to sig-
nificantly reduce the overall detention time needed to achieve the same degree
of treatment. Hudson (10) recommends a design practice of a minimum of three
compartments.
The recommended time of flocculation is reported by Rich as 10 to 30
minutes and in Water Treatment Plant Design (4) as 20 to 60 minutes.
Methods for achieving flocculation in water treatment plants are briefly
outlined below.
A) Mechanical Flocculators - Package plant manufacturers provide units
with 1 or 2 compartment flocculation tanks and vertical paddles and 10-30
minutes detention time; with square tanks and variable speed paddles and 13-27
minute detention times; and with 2 compartment tanks with variable speed
horizontal paddles and 17 minute detention time. Baffles may be included to
break up the rotational movement of the liquid.
B) Hydraulic Mixing - These avoid the use of mechanical equipment, but
are not as operationally flexible as mechanical units. One manufacturer
provides hydraulic mixing via a series of compartments having a 10-30 minute
detention time and connected by a large diameter pipe.
12
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C) Sludge Blanket - Several manufacturers use a solids contact process
for flocculation. Variations of this process include those with mechanical
flocculation in the chamber center and those with no external power input.
Power requirements and maintenance of mechanical equipment are minimal com-
pared with mechanical type units.
Amirtharajah (11) favors mechanical flocculation for the operational
flexibility needed with a varying raw water quality. It is considered dif-
ficult to build a blanket with low-turbidity water. The criticism of solids
blanket units being unsuitable for stop-start operation was not found valid by
Amirtharajah in field work in Sri Lanka where he found no difference between
intermittent and continuous operation with alum floe.
Sedimentation
Sedimentation is typically performed in package plants in either square
or round hopper-bottomed tanks or in tubes or lamella separators. Upflow
clarification in a 3olids-contact system is an alternate method for liquid-
solids separation.
The performance of the sedimentation step is affected by several design
features. The inlet, reported by Canale and Borchard (12) to be the most
critical appurtenance, needs to be designed so as to spread the incoming water
uniformly over the entire cross-section of the sedimentation tank. In this
manner, hydraulic short-circuiting of the tank can be minimized. The impor-
tance of this is sometimes disregarded in small plants.
Tube settlers, introduced in the mid-1960's apply the shallow depth
principles suggested by the work of Hazen and Camp to reduce the detention
time required for sedimentation. O'Connell (13) reports the Chevron configu-
ration has the highest perimeter of any common shape of the same area, and
thus the lowest Reynolds number. The tubes are composed of PVC or ABS
plastic. Sludge will 3lide down the plastic surface if the tubes are inclined
steeply enough. Slightly inclined tubes must be cleaned by draining when the
filters are drained for backwashing.
Conley and Hansen (14) say settling tubes should be located so the bottom
of the tubes is at least 4 feet from the bottom of a rectangular clarifier
while the top of the tubes should be 1 to 2 feet below the top of the effluent
weir.
Walker (15) recommends surface loading rates, in the sedimentation tank
itself, of 500 gpd/sq ft as being safe even for cold surface waters. He
continues that tanks of less than 15 feet diameter are subject to too much
short-circuiting and should have smaller surface rates.
Walker states that surface loading rates of 2 to 3 times those for
standard clarifiers are used for high-rate settling units. Canale and
3orchardt (12) report detention times of less than 10 minutes are common.
Loading rates in use for package units equipped with tube settlers are
100 and 150 gpd/sq ft.
13
-------
Package solids contact units on the market use a range of loading rates
from 0.6-7 gpm/sq ft and detention times of 40-105 min. Conley and Hansen
(14) report that this type of unit reduces the flocculation/settling time to 1
hour, primarily because of superior flocculation, but their opinion is that
the skill required to operate sludge blanket clarifiers precludes their use in
municipal practice.
Hudson (16) states tubes can be used in solids-contact clarifiers to
stabilize the floe blanket. They will reduce surface loadings and help to
restrain density current, but Conley and Hansen say that the reduced time may
not allow adequate flocculation to be achieved.
Filtration
Package water treatment plants can have either gravity or pressure
filters.
Host units are available with dual or multi-media filters. These make
greater use of the filter depth. Dual media filters generally consist of a
12-14 inchlayer of anthracite coal on top of a 6-15 inch layer of silica
sand. The anthracite coal has a specific gravity of 1.35 to 1.75, as compared
to the sand's specific gravity of 2.65 so even though particles of anthracite
coal are used that are larger than the sand particles, the anthracite with
larger voids will remain above the sand after backwashing. Mixed media fil-
ters contain a third layer of garnet sand below the anthracite coal and silica
sand. The garnet sand has a specific gravity of 4-4.2, and will remain at the
bottom of the filter even though it may consist of smaller particles, and thus
smaller voids than the silica sand.
The size of the various media should be specified so there is a small
amount of intermixing at the interfaces of the layers. Baumann (17) recom-
mends choosing media sizes so that neither substantial intermixing nor a sharp
interface between media layers occurs.
Flow rates are 2 or 3 gpm/sq ft for gravity sand filters In package
plants on the market and range from 2*6 gpm/sq ft for dual and multi-media
filters.
Baumann (17) reports that "with adequate chemical pretreataent and filter
design, there Is little difference In filtered water quality from filters
operated at rates between 2 and 6 gpm/sq ft."
Backwashing rates used Is package plants are usually 15 gpm/sq ft. Some
units are equipped with a surface wash as an auxiliary for cleaning.
Disinfection
Package plant manufacturers provide equipment for feeding chlorine for
pre- and post-disinfection but disinfection is not an inherent part of package
plant design. The desiafaction systems employed are not unique to package
plants. The systems employed at the plants mointored In this study were
simple and generally consisted of gaseous chlorinators or pumps for adding
chlorine solution.
14
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MANUFACTURERS
Various equipment manufacturers were contacted in an attempt to ascertain
the number and types of package plants presently being marketed. At the
outset of the study a list of fifteen probable manufacturers compiled in a
previous study, were asked to supply product information and lists of instal-
lations. Inquiries were later made to twenty manufacturers and suppliers
listed in the Thomas Register. Eight companies were found to be presently
marketing package potable water treatment plants for municipal use. Manufac-
turers' equipment briefly described in this section includes units that have
wide application and are truly package units, i.e., largely preassembled and
providing full treatment. Manufacturers producing package units strictly for
special applications such as ion exchange.or softening were not included.
Visits were made to four of these manufacturers. The visits were used to
gain information concerning the future plans of the manufacturers, their
problems and their attitudes toward customers and the various regulatory
agencies with which they deal. One manufacturer was introducing a micropro-
cessor that will control the coagulant dose based on effluent turbidity
measurements. This manufacturer had also redesigned much of its product line
including adjustment of flocculation times and tube settler loading rates.
Another manufacturer was beginning to recommend the use of aluminum tanks
instead of steel due to the difficulty of guaranteeing rust protection on the
steel tanks. The manufacturers had varying amounts of difficulty with state
agencies depending upon the state and the manufacturer. One manufacturer had
little difficulty while another designed a different plant for each state in
which it dealt. All of the manufacturers visited were very competitive. To
this end these manufacturers were prepared to provide extensive engineering
time to work with a customer or a customer's consulting engineer.
Two manufacturers were contacted that had removed themselves from the
municipal package water plant market. These manufacturers removed themselves
due to difficulties they encountered in dealing with the many regulations
involved in funding and permitting public water treatment plants. These
manufacturers now deal almost exclusively with industrial customers.
Products of the eight companies identified as presently marketing package
plants are summarized on the following pages.
CULLIGAN USA, NORTHBROOK, ILLINOIS
15-265 gpm Multiple trains can be usqd
Grit removal - optional - cyclone separator
Rapid Mix - In line chemical addition, not baffled
Flocculation/Sedimentation -
"Contact flocculation in a depth clarifier." Chemically treated
influent is introduced at the top of the depth clarifier, which is
packed with a coarse media; particulates and floe contact already
trapped floe in the media.
Loading rate 7 gpm/sq ft
15
-------
Filtration - Pressure Filter
IS in anthracite 0.67 mm effective size
9 in Calcined Aluminum Silicate 0.42 mm effective size
3 in garnet sand 0.37 mm effective size
Surface loading rate 7 gpm/sq ft
No surface wash
Header lateral underdrain
ENVIRONMENTAL CONDITIONERS, INC. VANCOUVER, WASHINGTON
Rotoflov C, D C10—250 gpm) Rotoflov E, F (10-400 gpm)
Rapid Mix - Static in line mixing
- Baffled pipe mixer - 2-6 ft/sec flow velocity
- 1-5 ft mixing distance
Flocculation -
Mechanical - Vertical paddles
- Paddle tip speed variable
- Detention time 10-30 min
- 1 or 2 compartments
Hydraulic - A series of compartments connected by large
diameter pipe
- Detention time 10-30 min
Sedimentation - Rotoflov C+D systems do not use sedimentation
- Rotoflow E+F systems use open tank or tube sedimentation
- Tube loading rate 150 gpd/sq ft
Filtration - Dual media gravity filter
18-24 in anthracite effective size 1.0 ma
6-12 in silica sand effective size 0.45-0.55 mm
- Mixed media gravity filter
18 in anthracite effective size 1.0 mm
9 in silica sand effective size 0.45-0.55 mm
3 in garnet sand effective size 0.25 mm
3 is garnet effective size 2. mm
- Header lateral underdrain
Filter loading rate 2.-5. gpm/sq ft
A11 units equipped with surface wash
GENERAL FILTER CO., AMES, IOJA
Rapid Mix - Chemical solutions are added at the top of the mixing zone
and influent enters from the bottom* A mechanically driven
propeller mixes the influent and chemicals.
Flocculation/Sedimentation
- Flocculation occurs in a cone shaped zone contained in a
solids contact unit. Effluent flows down and radially
outward then up through a sludge blanket. Sedimentation
occurs in the upflow portion of the solids contact unit.
16
-------
Filtration - Anthrafilt media
Mechanical underdraln
INFILCO DEGREMONT, RICHMOND, VIRGINIA
Rapid Mix - Treatment chemicals, Influent and recycled precipitate
are mixed In a cylindrically shaped mix chamber with a
mechanical mixer.
Flocculatlon/Sedimentation
- A large cylindrical zone surrounding the rapid mix
chamber promotes solids separation. At the bottom
of this zone the solids are drawn into a conically
shaped chamber. A portion of the solids slurry is
discharged while the rest is recycled up into the
rapid mix chambers.
Filtration - Sand or dual media
- Gravity or pressure
- Filtration rates 2-6 gpm/sq ft
- Header lateral underdraln
MET PRO INC., HARLEYSVILLE, PENNSYLVANIA 10-900 gpm
Rapid Mix - Series 2000 uses a square tank, with a mechanical mixer.
Flocculatlon - Series 2000 uses a square flocculatlon tank, with a
variable rate vertical paddle mixer. Retention
time in the flocculator is approximately 18-27 min
Sedimentation - Series 2000 uses a cylindrical tank for a clarlfier.
Detention time in the clarlfier varies from 60 to 70 min
Flocculatlon/Sedimentation - Model 1300-100 (166 gpm) upflow
Solids contact, detention time 45 min
Filtration - Gravity Filter - Surface loading 2.8-4 gpm/sq ft
Backwash rate 15 gpm/sq ft
Dual media 18 in anthracite
\ 12 in silica sand
Header lateral underdraln
- Pressure filters - Media 13 in anthracite
12 in silica sand
- Surface loading 4 gpm/sq ft
- Backwash rate 15 gpm/sq ft
- Header lateral underdraln
- Air scour <§ 5 psl optional
17
-------
NEPTUNE MICROFLQC, INC., CORVALLIS, OREGON
10-1800 gpm
Sapid Mix - In line chemical addition
- Mixing time 2-6 seconds
- The mixing distance is variable, field data indicates
a distance of approximately 20 pipe diameters
- The Uaterboy Series C10—100 gpm) has a mixing chamber.
Flocculation - New units - Flocculation occurs in rectangular
two stage compartments
- d.t. • 17 min
- Electric paddle mixers, variable speed,
1/4, 1/3, 1/2 horsepower, horizontal shaft
- d.t. old units - 10-14 min
Sedimentation - Sedimentation occurs in tube settlers
- Tube shape - split hexagon
- Tube overflow rate 100 gpd/sq ft
Filtration - Mixed media filter
18 in anthracite 1.0-1.2 mm effective size
9 in silica sand 0.45-0.55 mm effective size
3 in garnet sand 0.25-0.35 mm effective size
- Surface loading 5. gpm/sq ft
- Backwash rate 15. gpm/sq ft
- Header lateral underdrain
PEBMUTIT CO., PARAMUS, NEW JERSEY
15-2100 gpm
Rapid Mix - In line chemical addition or mixing in an inlet flume
Flocculation/Sedimentation - Upflow solids contact units which use a
sludge blanket for flocculation and
sedimentation in one vessel
Centrafliter (15-115 gpm) -
Precipitator (60-920 gpm) -
\
Permujet (350-2100 gpm)
d.t. - 3 hr 28 min
rise rata - 0.53-0.61 gpm/sq ft
d.t. - 60 min or 40 min with
settling tubes
Rise rate - 1.25 gpm/sq ft
d.t. « 90-105 min
Rise rate - 1.0 gpm/sq ft
Filtration - 24 In silica sand 0.45-0.60 mm effective size
- Disc strainer underdrain
- Filter rate 2 or 3 gpm/sq ft
- Backwash rate 15 gpm/sq ft
18
-------
WESTERN FILTER CO., DENVER, COLORADO
30-200 gpm
Rapid Mix - "Reverse involute" flash mixing chamber
Flocculation/Sedimentation
- Flocculation is promoted via solids contact employing a
sludge blanket. The solids are kept in suspension with a
mechanical mixer housed in a conically shaped 'downcomer'
chamber below the flash mix chamber. Effluent from the
'downcomer' flows radially outward and upward to launders
equipped with weirs. The launders conduct the effluent
to a filter.
Filtration - Single or dual media
Single media depth 24 in
Media: Silica sand 0.45-0.55 mm effective size
Anthrafilt 0.6-0 7 mm effective size
Granular carbon 14 x 40 mesh
Filter loading 2 or 3 gpm/sq ft
Backwash rate 15 gpm/sq ft
Header lateral underdrain
19
-------
SECTION 5
PROCEDURES
FIELD PROCEDURES
The latent of the field research was to evaluate water quality data £rom
package water treatment plants to determine if they consistently meet federal
and state drinking water standards. In addition to water quality determina-
tions, the operators' responsibilities and the designs of the various units
were to be studied. A previous survey of package plants in nearby states
included analysis of grab samples taken at several plants (18). Data from
these samples indicate that some of the sites were not meeting drinking water
requirements. The limitations of a single grab sample preclude assessing the
ability of package plants to consistently meet the drinking water standards.
Sampling from selected sites on a continuing basis increases the ability to
assess the plants' performance. Variability of the source water during
seasonal changes may have a large Impact on these plants' capabilities. The
wetter seasons of autumn and spring may present difficulties in turbidity
and/or color removal. The intent was to observe and sample from package water
treatment plants on a routine basis over an extended period.
The previously mentioned survey of package water plants conducted during
the autumn of 1977 was used to identify prospective sites for use in this
research. The survey provided knowledge of plant ownership, manufacturer and
sources of water. The survey included comments on the level of maintenance
and staffing of each facility. From this information, a list of potential
plants was made. Well operated plants were selected that included various
source waters and manufacturers. Emphasis was placed on identifying plants
supplying households rather than plants serving parks or privately owned
resorts since plants in year-round operation were desired. While certain
chemical and physical analyses were to be performed at the various water
plants, It was known that the microbiological analyses would have to be per-
formed in the more controlled environment of a laboratory, so the availability
and proximity of suitable laboratory space were a part of the selection
criteria for prospective water treatment plants.
Preliminary visits were made to confirm the previous survey data, measure
travel time to the nearest laboratory, and to determine the level of coopera-
tion that could be expected at each site. Eleven package plants were visited
on the preliminary trip (Feb. 22-Mar. 3, 1979). Information was gathered
concerning the operation of each plant, the number of operators, their back-
ground and training, and the analyses performed routinely. Samples of the raw
water were collected and analyzed for inorganic pollutants. The appropriate
individual in the state health department was asked about the availability of
20
-------
laboratory space, incubators, and access to an autoclave for use in bacteriol-
ogical determinations.
Based on the above criteria, the package plants listed in Table 3 were
chosen for evaluation. These plants are labeled as sites W, T, V, R, P, and
C.
Sites using groundwater sources were not selected owing to water quality
consistency and consequent ease of operation. Five of the six plants were
made by Neptune Microfloc and provided water to cities or unincorporated towns.
The sixth plant was a Permutit system located at a state park that operated
all year.
A typical field trip lasted approximately five days. A different water
treatment plant site was visited each day during at least the first three days
of the trip. Chemical analyses were performed at the site and microbiological
samples were collected. The samples for microbiological analyses were taken
to the state laboratory. On days subsequent to the first one, any necessary
counting and/or transferring of colonies was also done upon arrival at the
state laboratory. Often after the three sites were visited and while the micro-
biological samples were incubating, the plants were revisited to gather more
data or to consult in plant operations.
The field trips were conducted from June 1979 through April, 1981, accord-
ing to the schedule in Table 4. Interruptions occurred due to weather and the
necessary support work. Field trips were taken approximately every other week
thus insuring monthly observation of each plant through seasonal changes and
varied environmental conditions.
The intent of the initial field trips was to observe the operation of the
plants, to perform chemical analyses side by side with the operator and to
collect treatment and distribution system samples for microbiological analyses.
Observation of the operator included seeing that person change coagulant doses
and perform any necessary routine maintenance. This facilitated evaluation of
the operational requirements of these plants. The side by side chemical
analyses provided confirmation o£ the operator's data on the daily operational
log, which was submitted to the state health department. Provided the results
of the side by side analyses were comparable, the operational logs were to be
relied upon as a source of performance data for this research. The micro-
biological samples were analyzed for total coliforms and the plant effluent
and distribution system samples were analyzed for standard plate count.
The side by side analyses with the operators generally compared quite
favorably. Aa more field trips were completed and the operational logs of the
operators were studied, doubts arose \is to the validity of some of the data
from a few of the plants. While the results of the side by side analyses were
similar, these data did not always appear in the operational logs. Growing
familiarity with the operators permitted questioning of those at the instal-
lations with discrepancies in their logs. The data, most often effluent
turbidity, were not reported faithfully when they were greater than the
standard i ntu, out of fear of repercussions from the state health department.
This meant some of the monthly operational logs could not be used as sources
of performance data of these plants.
21
-------
TABLE 3
SITE
MODEL
YEAR
DESIGN POP. SERVED/
FLOW NO. OF METERS
RATE
(gp«)
W
Neptune
Microfloc
AQ-40
1973
200
1500/552
Neptune
Microfloc
AQ-40
1973
200
1000/360
K)
ro
Neptune
Microfloc
AQ-40
1976
JLOO
/423
R
Neptune
Microfloc
AQ-112
1972
560
-/1680
Neptune
Microfloc
Uater Boy
1972
100
-Mil
Peruutlt
Penaujet
1971
200
State Park
* PSD - Public Service District
FACILITIES IN STUDY
AVG.
VOLUME
PER DAY
(gals)
GROUP
SERVED
TYPE OF
DISTRIBUTION
PIPE USED
SOURCE
110,000 city
PVC
surface
impoundment
78,000 city
PVC, cast iron
asbestos cement
surface
Impoundment
72,000 PSD*
PVC
river
330,000 PSD*
PVC
river
82,000 PSD*
PVC
surface
impoundment
57,000
State
Park
asbestos
cement
river
-------
TABLE 4 DATES OF FIELD TRIPS
MONTH
SITE U
SITE R
SITE V
SITE T
SITE C
SITE P
Hay
June
July
Aug
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Oct
Nov
Mar
Apr
1979
1979
1979
1979
1979
1979
1979
1979
1980
19 BO
1980
1980
1980
1980
1980
1980
1980
1980
1980
1981
1981
10
16
13
03
04
23
11
19
1
11
20
14
01, 30
05
23
04-06
28-01
12
02-04, 09
18
30
06
22
04-06, 17-20
31-02
14-17
10
17
31
07
01, 28
15
13
08
25
28
15
08
31
27
16
14
07
23
27
14
11
29
15
13
08
23
28
13
-------
The data from the visits began, to show at least two sites were having
difficulty meeting the effluent turbidity standard of 1 ntu. Extended periods
were spent at these plants having difficulties.
The chemical analyses performed routinely for this 3tudy are listed in
Table 5. On occasion, samples were taken for later trihalomethane analyses or
for determination of primary and secondary contaminant levels.
Samples at each water treatment plant were collected from the raw water,
the plant effluent and the distribution system. Five of the six plants had
raw water taps from which the influent was sampled. The remaining plant was
sampled directly from its river source. All of the plants had sinks for use
in chemical analysis of their treated effluent. These were used as sampling
sites for the finished water. The sinks had water piped to them from the
clearwe.ll thus providing a composite of the plant effluent produced over a
period of time. Two. samples from each plant's distribution system ware col-
lected at various public places, e.g., schools, service stations-* restaurants.
Attempts were made to have one sample from an intermediate point of the dis-
tribution system and one from an end or extreme point of the system. Most of
the plants' distribution systems were sampled several times and an effort was
made to change the sampling points each time. On occasion, the same sampling
sites had to be used again because of the small number of accessible public
sampling points within each system.
Autoclaved nalgene bottles containing sodium thiosulfate to reduce any
chlorine were used for microbiological sample collection. Total coliform
tests using the membrane filter technique were performed on all samples from
each site. M-Endo agar media was used because it could be prepared at the
University of Cincinnati laboratory, chilled, and transferred to either of the
two field laboratories for use during that week. One plant per field trip was
sampled on a Monday and that plant's membrane filter total coliform determina-
tion was confirmed via the multiple tube fermentation technique.
The standard plate count examination was made on the plant effluent and
distribution system samples. The agar was prepared at the U.C. laboratory,
allowed to solidify and then transported to either of the two field labora-
tories. Duplicate plates of three different dilutions were run for each of
the three samples from each site.
Samples were sent to USEPA's Cincinnati Laboratory for analysis of chem-
ical contaminants in the primary and secondary Drinking Water Regulations.
Samples from each water treatment pl^nt were also collected for trihalomethane
analysis by the University. The level of trihalomethane in the plant effluent
was measured along with the terminal 2 day THM concentration of each plant's
raw water.
The samples of the plant effluent used for measuring the levels of tri-
halomethanes present were collected in 40-ml vials containing sodium thiosul-
fate to quench any chlorine residual present. The sample vials were sealed,
without any air space, with a teflon lined septum and a screw cap. The
quenching of the chlorine prevents any further formation of trihalomethanes,
thus the sample is essentially an instantaneous trihalomethane measurement. By
capping the sample with no airspace, volatilization and loss of the THMs is
24
-------
sm ni
TABLE 5 ANALYTICAL METHODS
ALKALINITY UAUMUtSS TOMttlOIT*
color c<
parator
¦ethyl
orange ti-
tration
titration
nepheloauter
lUch 2100A
pH MUr
aethyl
orange ti-
tration
titration nepheloaeter
Hf IMT-1000
N
U»
colorlaeter Mthjrl
orange ti-
tration
titration
nepheloaeter
Uach 2100 A
pH awstar
aethyl
orange ti-
tration
titration wspbeloMtti
Uach 2100A
colnrlaeter
¦ethyl
orange ti-
tration
titration nepheloaeter
Turner Oealgna
pH aeter
tUch fclt
with
dropper
bottle
titration nepheloaeter
with dropper Uach 2I00A
bottle
Project pU meter
¦ethyl
purple ti-
tration
titration nepheloaeter
Turner Dealgna
FIUX CI
OTHHt
effluent and
ayatea; 0F0
color coapar-
ator
iron 1 aanganeae
color coaparator
affluent only
OPO color
coaparator
effluent and
aye tea; DPI)
color compar-
ator
effluent only
DfO color
coaparator
Iron, color
comparator
effluent only
DPD co lot1
coaparator
effluent and
ayatea; DPI)
color coapar-
ator
iron, color
coaparator
effluent and
ayatea; DM)
and apectro-
pbotoaeter
teaperature
-------
prevented. The reaction time of the chlorine with any precursor material
present is the sum of the plant treatment time and the clearvell retention
time.
The THM formation potential is a measure of the level of precursor
material present in a water sample. The influent sample was chlorinated with
a sufficient amount of chlorine to maintain a free residual over a 2 day incu-
bation period which approximated the theoretical detention time found in the
distribution systems. Upon completion of the incubation period the chlorine
residual in part of the sample was measured and part vas quenched and stored
in a 4U ml vial with no headspace to prevent volatilization. The level of the
THMs present* upon Incubation and quenching, is a measure of the terminal 2
day THM concentration of the sample. The formation potential is defined as
the difference between the terminal THM concentration and the instantaneous
TIM concentration. In this work, the instaneous THM concentration of the raw
water samples was not measured and was assumed to be very low or zero. The
terminal concentration is that reached after incubation for a predetermined
period at a predetermined temperature and pH. The incubation temperature was
not controlled at the temperature of the influent when the samples were taken.
The samples were Incubated at room temperature and the pH was not controlled.
This makes it Impossible to compare the raw water terminal THM samples with
the effluent water Instantaneous samples. The terminal THM concentrations
will serve only as an indicator of the level of precursor material present.
The analyses were performed on a Varlan 2800 Gas Chromatograph (G.C.)
equipped with a Hall Electrolytic Conductivity Detector and a Huston Instru-
ments 2-pen strip chart recorder. The carrier gas was Nitrogen at a flow rate
of 55 ml per minute.
The purge apparatus was a 50 ml unit with Nitrogen purge gas at a rate of
40 ml per minute. The trap was a 6" x 1/8" column filled with Tenax G.C.
packing.
Twenty milliliter samples were purged and trapped for 11 minutes at 25 °C.
At the end of the 11 minutes, the trap was attached to the cool (45*C) G.C.
column and desorbed for 6 minutes. The column was then heated at a rate of
24*C/min to 117*C held 3 minutes* then temperature programmed at a rate of
6*C/mln up to 195*C and held for the remaining time is the 27 minutes total
run time.
The peak heights were compared to those produced by standards analyzed in
the same fashion each day of analysis.
26
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SECTION 6
CASE STUDIES
TREATMENT PROCESS DESCRIPTION
The state health department having jurisdiction over the 6 facilities
studied required a class I operator's license for operators at facilities using
groundwater sources and a class II license at facilities using surface water
sources. Water treatment plants having inadequately licensed operators were
requested to retain an adequately licensed operator as a supervising operator.
The supervising operator visited the plant approximately weekly to check on
the plant's operation, instruct the staff and help with any operational
problems.
Pertinent data for each plant are summarized in Tables 3 and 6. Five of
the 6 plants studied were manufactured by Neptune Microfloc Inc., and were
functionally similar. A general description of these units follows.
The 5 Neptune Microfloc units had Influent rate controlling valves.
Treatment chemicals were added as solutions directly into the influent pipe
near the Influent valve. Chemical mixing occurred in the influent pipe and/or
in a mix chamber. The influent then entered the flocculator at the top while
the flocculator effluent was drawn off from near the bottom. The flocculators
employed variable speed vertical paddles for agitation. Four of the 5 units
had a horizontal baffle plate at mid-depth to prevent short circuiting.
'Sedimentation occurred in tube settlers. Each tube was hexagonal in
shape, approximately 2 In. wide and 39.5 in. long. The tube banks were
inclined upwards at a 7V slope to facilitate solids removal in the
backwash cycle when the direction of flow was reversed.
Four of the 5 units had float depth controls that pneumatically control-
led the effluent valves. The other plant had a float that was mechanically
connected to the effluent valve. Four of the 5 facilities had below grade
clearwells which contained the Intakes for 2 high service pumps and 2 backwash
pumps. The fifth unit had an above grade clearwell that gravity fed a wet
well containing the high service pumps' intakes.
Each of the 5 facilities had 1 control panel which controlled the in-
fluent pump or pumps, the Influent rate control valve, the chemical feed
pumps, the effluent valves, the high service pumps, backwash pumps and back-
wash valves. A cam timer in the control panel regulated the backwash cycle.
Upon manual initiation or due to filter headloss beyond a certain limit the
cam timer would shut off the plant and backwash the appropriate filter. At
27
-------
one facility the cam timer was not working properly and had to be turned
manually. The tube settler chamber associated with the filter to be back-
washed rapidly drained at this time cleansing the tubes of settled material.
Site U
The chief operator at site W was not licensed by the state, although he
has been operating this facility since its construction. The other operator
was in the process of becoming licensed at the close of the study period. The
staff's responsibilities included plant operation, distribution system mainte-
nance and meter reading. The staff occasionally performed tasks for the city
that were not related to the water treatment plant. The staff estimated
however, that 85-902 of their time was spent at the water treatment plant,
which was in operation an average of 9 hours per day.
The plant (see Figures 2 and 3) was started early each morning. The
chemical solutions were checked and more were made as necessary.' The pH and
turbidity were measured and recorded hourly throughout the time the unit was
operating. Whenever the plant had to be left unattended an operator returned
hourly to insure the unit's proper operation.
Site W water quality characteristics and microbiological analysis data
are found in Table 7. The raw water was of consistently high quality (4-30
ntu) as was the plant effluent, except for one effluent turbidity value of 2
ntu. The operator thought this value was the result of a low flocculator pti
caused by efforts to improve color removal. Coliform levels entering the
plant ranged from 2 to 4,400 per 100 ml. Effluent chlorine residuals were
above 1 mg/1 but some distribution system samples had no free chlorine
residual. No coliforms were found in any effluent or distribution samples
and 7 of 9 standard plate counts were less than 20 per ml.
THM values are reported in Table 8. Effluent instantaneous levels were
approximately at the 100 yg/1 limit set for TTHM by the USEPA for water
distribution samples of systems serving 10,000 or more population. The raw
water terminal TTHM values of 184 and 321 yg/1 indicated high concentrations
of precursor material.
Results of the chemical analyses performed by USEPA are found in Table 9.
All of the primary and secondary contaminant levels were met in the effluent
and distribution system samples collected. The Influent water was also of
high quality with only the secondary limits for color, iron, and manganese
exceeded.
A major contribution to the consistent high quality effluent produced at
site VI was the operational staff. The chief operator has been operating this
plant since its start up in 1973 and this is the only staff in the study that
recorded hourly turbidity and pH measurements. Another factor contributing to
the effluent quality was the uniform quality of the source reservoir. The
maximum influent turbidity recorded by the study was 29.7 ntu. The operator
indicated that the uniform quality of the source is typical for this plant.
The monthly operations reports submitted to the state show the influent turbi-
dity exceeded 50 ntu on 2 occasions for 2 days between May 1979 and July 1980.
29
-------
CHEMICAL
FEED TANKS—
SINK
BENCH
FLOCCULATOR
•BACKWASH
WASTE VALVES
CONTROL PANEL-
TUBE SETTLERS
AND FILTERS
HIGH SERVICE
AND BACKWASH
PUMPS
EFFLUENT AND
BACKWASH VALVES
OFFICE
WORKSHOP AREA
CHLORINE
CYLINDER
ROOM
Figure 2. Site W Facility layout
30
-------
FLOCCULATOR
m-m
!i !!!» ! iMii!
ii >"
11 II
n I |
iHHJ-MW-U!
i. it i
i'ii
1 !!1
i 11
Jill!!
i
i; ji !< i
it ¦•!) i
cfOU—¦t~tt-tTB
"I
M I
II <1
03=
u
B
BACKWASH
WASTE VALVES
TUBE SETTLERS
1
r--i-
EFFLUENT AND
BACKWASH VALVES
Figure 3. Sice W Neptune MIcrofloc AQ-40 200gpm
31
-------
TABLE 7 SITE W MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
uatk
HAW
Total
ColKiirn
100 al
CLKAKUtl.t EFFLUENT
fr«e
a
ag/1
Total
ColltafM
100 ¦!
Std.
Plate
¦I
1ST DISTRIBUTION
Free Total
CI CitUfonw
ag/l 100 al
Sid.
Plate
•1
2ND IXSTKIHUTION
Free
CI
¦*/L
Total
Coll fonn
100 al
Std.
Plata
al
7/16/79
8/13/79
10/03/71*
10/29/79
12/04/79
1/24/80
6/11/80
11/19/80
4/01/8l
18
4.400
640
4
lt>0
31
26
280
2
2.0
2.0
1.4
1.6
2.
1.0
1.6
1.7
1.3
4
< 1
< 1
1.4
1.0
0.0
0.7
1.4
0.9
0.8
1.1
0.8
1
150
< I
1.1
l.l
0.0
0.0
0.0
0.1
1.6
0.0
0.6
300
< 1
18
UAlfc
P*
Kaw Clearwell
Effluaat
ALKALINITY
(ag/1 aa CaCO_)
Kaw Clearwell
Effluent
UAKONCSS
(ag/1 aa CaCo.)
Kaw Clearwell
Effluent
TUKttlUm
(ntu)
Kaw Clearwell
Efflueat
CI
(•8/U
Clearwell
Effluent
5/10/79
7.2
-
64.
82.
92.
-
-
0.9
1.4
7/16/79
-
-
28.
82.
100.
100.
5.0
0.3
2.0
8/13/79
7.6
7.5
69.
102.
92.
82.
4.2
0.4
2.0
10/03/79
-
-
86.
77.
67.
68.
19.
0.8
1.4
10/29/79
6.9
7.2
50.
80.
71.
78.
9.2
2.0
1.6
12/04/79
7.5
7.8
48.
78.
78.
73.
11.5
0.3
> 2.
1/23/80
7.5
7.4
55.
80.
66.
86.
12.0
0.2
1.0
6/11/80
7.2
7.5
67.
80.
99.
99.
li.O
0.3
1.6
11/19/80
7.1
7.8
47.
91.
77.
78.
29.7
0.9
1.7
4/01/81
7.2
8.2
40.
51.
77.
90.
12.8
0.2
1.3
-------
TABLE 8 SITE W TRLHALOMETHANE ANALYSIS
INSTANTANEOUS THM
DATE SAMPLE CHC1 CHC1 Br CUClBr CHBr TOTAL
Tint
( g/i) ( g/i) C g/l) ( g/D ( g/D
t
10/29/79 Effl. 101. 2.2 N.D. N.D. 103.
06/11/80 Effl. 92.7 8.9 N.D. N.D. 102.
TEKMINAL Tffti (2 DAY)
DATE SAMPLE CHLORINE CHCL CHCl^Br CHClBr CHBr TOTAL
DEMAND THM
(ng/1) ( g/D ( g/1) ( g/D ( g/1) ( g/1)
06/11/80 lnfl. 1.76 139. 45. N.D. N.D. 184.
06/11/80 lnfl. 1.91 288. 33.5 N.D. N.D. 322.
N.D. - None Detected
-------
TABLE 9 SITE W CHEMICAL ANALYSES PERFORMED BY USEPA (mg/L except as noted)
fltUUHV MIX
FEB. 1979
1NFL.
JUNE 1980
1NKL.
1NKL.
OCT. 1980
£fr>'L. 1ST DIST.
2ND 01ST.
1NFL.
MARCH 1981
OffL. 1ST OIST.
2ND DIST
AMSUUC (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
HAKIUH (1.)
0.25
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
<0.2
CAUUIM (0.01)
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
OMtUHltM (0.05)
0.011
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
k'UJuilllMC (1.4 to 2.4)
0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
< 0.1
LEAD (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
MhktCUlV (0.002)
0.0009
0.0018
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
NITUATE-N (10.)
< 0.3
-
< 0.3
< 0.3
<0.3
<0.3
0.6
0.6
0.3
0.3
SU.EN1UH (0.01)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
0.005
0.005
0.005
S1LVE8 (0.05)
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
StCOMIAKV MO.
CNUNUUE (250.)
< 10.
-
< 10.
< 10.
< 10.
< 10.
< 10.
< 10.
< 10.
< 10.
C0UW (IS C.U.)
40.
3.
50.
2.
3.
3.
15.
2.
2.
2.
cures* (l.o)
< 0.02
0.03
0.06
< 0.02
< 0.02
0.15
< 0.02
< 0.02
< 0.02
0.11
1MOM (0.3)
0.59
0.26
0.84
< 0.1
< 0.1
< 0.1
0.25
< 0.1
<0.1
< 0.1
MANGANESE (0.05)
0.04
0.12
0.54
0.03
< 0.03
< 0.03
0.09
< 0.03
< 0.03
< 0.03
SOLVATE (250.)
38.
40.
31.
49.
48.
46.
44.
61.
60.
60.
TOTAL DISSOLVED SOLIDS (500)
7U.
139.
116.
160.
164.
158.
123.
158.
164.
165.
ZINC (5.)
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
ALKALINITY
31.
62.
41.
66.
70.
70.
20.
50.
50.
49.
CAUUIM
15.11
25.
18.0
18.7
18.4
18.1
17.0
26.7
25.6
26.0
HAkUNESS
62.
92.
64.
64.
64.
65.
76.
96.
94.
92.
MACNES1IM
4.50
7.22
4.97
4.98
4.95
4.87
5.21
5.43
5.47
5.46
SUU1IM (20.)*
4.5
11.9
6.0
29.8
31.5
29.3
7.8
15.4
16.1
16.3
srecuic conductance (jjhuos)
« 25*C
146.
229.
174.
276.
283.
270.
196.
267.
266.
266.
*TImj US ETA promulgated, on August 27, ItllO, * tuxlluai aonltorlng tcqulreaeiit to becaw
effective la February 19112. Mi lie ao uxlaua cmimImiK level kss beeu set for
Mxllua, tte preamble to the aaemlaeats ludkaun that '/Urn^/l should be llie goal.
-------
Site T
The operational staff at site T consisted of 2 positions. These 2 posi-
tions were held by 4 different people during the study period of 16 months.
One operator held his position for the first 6 of the 8 field trips conducted
at this site. This operator became a class I licensed operator during this
period. At the state health department's request a consultant operator was
retained by the city to assist and advise the site I staff. The consultant
operator visited approximately once per week. The staff's responsibilities
Included: plant operation, meter reading, distribution system repair and seme
work for the city not related to water treatment. When duties outside the
water treatment plant required the staff's attention, the facility was left
unattended.
The treatment plant (see Figures 4 and 5) was operated an average of
6.5 hours daily. Analyses were performed in the morning. The filters were
backwashed based upon effluent turbidity or time. When the operators were
inexperienced, they had used filter backwashing as a method of wasting higher
than 1 ntu effluent. After backvashing, they adjusted the chemical doses
and put the plant back in operation. The cam timer at 3lte T did not function
and had to be turned by hand so that the backwash cycle was not timed. Thus,
a set volume of water was used to determine the length of the backwash.
Table 10 summarizes the water quality characteristics and the micro-
biological analysis measured at site T. The maximum influent turbidity was
1U.4 ntu. The effluent turbidity exceeded the 1 ntu standard on 2 occasions.
The first occasion June 7, 1979 was due to an influent pump failure and con-
sequent extended filter operation to make up for the failure. The second high
effluent turbidity resulted from a large distribution system leak repair
keeping the operators away from the plant for an extended period. The ef-
fluent pU is erratic ranging from 6.6 to 9.5. Raw water total colifonns
ranged from less than L0 to 8,900 per 100 ml. Total coliforms were detected
In one treated water sample (12/100 ml). The sample was collected at the
kitchen sink of a residence and no free chlorine residual was present. Five
of the Id distribution system samples collected had no free chlorine residual
although effluent samples ranged from 0.3 to 1.3 mg/1. The standard plate
counts of treated water samples ranged from <1 to 110 per ml.
The instantaneous TTHM analysis indicated some levels of TTHM at or near
the 100 ug/1 limit set by the USE^A for systems serving 10,000 or more popula-
tion (Table 11). The samples from October 28, 1980 reflect a progression due
to their respective greater chlorine contact times. The raw water 2 day ter-
minal TTHM analysis resulted in TTHM concentrations of 440 and 498 ug/1.
The chemical analyses performed by USEPA indicate that all treated water
samples had chemical concentrations below the primary maximum contaminant level
(MCL) (Table 12). Iron and manganese in 3 and 2 samples respectively were the
only secondary MCL's exceeded. The influent water exceeded the secondary
limits for color, iron, and manganese.
Seven of the 9 field trips to this facility found the effluent turbidity
meeting the 1 ntu standard. The low influent turbidity (3-10 ntu) of the
35
-------
CHEMICAL
FEED TANKS—,
SINK
BENCH
a
FLOCCULATOR
BACKWASH
WASTE VALVES
CONTROL PANEL
TUBE SETTLERS
AND FILTERS
HIGH SERVICE'
AND BACKWASH
EFFLUENT AND
BACKWASH VALVES
PUMPS
DESK
CHEMICAL
STORAGE
CHLORINE
CYLINDER
ROOM
Figure 4. Sita T Facility layout
36
-------
FLOCCULATOR
FILTERS
BACKWASH TUBE SETTLERS
WASTE VALVES
EFFLUENT ANO
BACKWASH VALVES
Figure 5. Sice X Neptune Microfloc AQ-40 200 gpm
37
-------
TABLE 10 SITE T MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
DATE
IUU
CLEAKWELL EFFLUENT
1ST DISTHIUUT1UM
2ND DISTRIBUTION
Total
VrtNi
Total
Std.
Free
Total
Std.
Free Total
Std.
Collfonta
CI
Collfonut
Plate
CI
Coll tonus
Plate
CI Collfonui
Plate
100 »1
«g/l
100 ml
¦1
¦k/i
100 ml
>1
¦g/1 100 al
¦1
6/07/79
80
1.3
< 1
15
1.6
< 1
30
1.0 < 1
10
7/30/79
8,900
0.3
< 1
no
0.0
12
2
0.0 < I
36
8/28/79
190
0.6
< 1
13
0.1
< I
31
0.0 < 1
40
10/15/79
140
1.2
<¦ 1
3
0.3
< I
1
0.0 < 1
1
11/13/79
12
0.4
< 1
110
0.2
< I
I
0.6 < 1
1
1/08/80
14
1.2
< 1
1
0.5
< 1
1
0.5 < I
3
6/24/80
<10
0.4
< 1
1
0.3
< I
1
0.0 < 1
14
10/28/80
306
1.0
< 1
4
0.5
< I
2
0.1 <1
6
4/14/81
24
0.7
< 1
< 1
0.2
* I
29
0.4 < 1
7
DATE
6/07/79
8/01/79
8/28/79
10/IS/79
11/13/ 79
1/08/80
6/25/8U
10/28/80
4/14/81
PH
tM Clucuell
Effluent
6.6
6.5
6.5
5.6
6.3
6.7
6.1
9.2
9.1
9.5
9.2
8.3
6.6
6.9
9.4
ALKALINITY
(ag/1 u CaCO_)
law Clearwell
Effluent
120.
15.
7.
36.
9.
10.
19.
9.
61.
62.
90.
34.
35.
35.
21.
29.
38.
HA80NESS
(•k/1 «« CaCo.)
law Clearuell
Effluent
TUHttlUlTV
CI
148.
44.
-
26.
17.
18.
15.
15.
-
40.
19.
20<
29.
30.
19.
19.
(ntu)
(¦g/1)
Haw
Clearwell
Clearwell
Effluent
Effluent
10.0
1.9
1.3
8.0
0.2
0.0
6.0
0.4
0.6
3.2
1.1
1.2
3.2
0.2
0.4
3.2
0.2
1.2
5.8
0.2
> 2.
10.4
3.2
1.0
3.4
0.7
0.7
-------
TABLE 11 SITE T 1K1HALGMETHANE ANALYSIS
INSTANTANEOUS TUM
DATE SAMPLE
ciici3
<|ig/i)
CMCl2Br
(lig/1)
CHClBr.
(pg/1)
C»lBr3
(lig/1)
TOTAL
THM
(pg/1)
06/25/80
Efi:l.
0.2
N.D.
N.D.
N.D.
0.2
06/25/80
Effl.
0.1
N.D.
N.D.
N.D.
0.1
10/28/80
Eft I.
78.6
5.7
N.D.
N.D.
84.3
10/28/80
1st Distr.
85.0
7.8
N.D.
N.D.
92.8
10/28/80
2nd Distr.
114.
8.8
N.D.
N.D.
123.
TERMINAL TllM (2 DAY)
DATE
SAMPLE
CHLORINE
DEMAND
(«g/l)
CHCI ^ CUCl^r CHCIBr2 CHBr^
(|ig/l) (pg/1) (lig/1) (|ig/i)
TOTAL
TllM
(lig/1)
06/25/80 Infl. 2.6
06/25/80 Infl. 2.9
288.
486.
152.
12.
N.D.
N.D.
N.D.
N.D.
440.
498.
N.D. - None Detected
-------
TABLE 12 SITE T CHEMICAL ANALYSES PERFORMED BY USEI'A (mg/L except as noted)
fttlMAUY HCL
FEU. 1979
1MH..
JUNK 1980
1MKL.
1NFL.
OCT. 1480
EKFL. 1ST DIST.
2ND DIST
AKStHiC (O.Oi)
< 0.005
< 0.005
< 0.0U5
< 0.005
< 0.005
< 0.0U5
BAKUM (1.)
< 0.2
< 0.2
< 0.2
<0.2
0.23
0.21
CADNIUK (0.01)
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
CHMIM1UH (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
VLUMlDt (1.4 to 2.4)
< 0.1
< .0.1
< 0.1
< 0.1
< 0.1
< 0.1
LLAU (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
HMtCUMY (0.002)
< 0.0005
0.0009
0.0005
0.0014
< 0.0005
0.0009
M1T8ATE-N (10.)
< 0.3
-
< 0.3
<0.3
< 0.3
< 0.3
SU.fc.NlUH (0.01)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
SILVKIt (0.0^)
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
StCONUAItY HCL
CHU4IUE (2S0.)
< to.
-
< 10.
< 10.
< 10.
< 10.
CUUNt (IS C.U.)
8.
30.
70.
3.
6.
11.
COrt-EU (1.0)
0.07
0.03
< 0.02
< 0.02
< 0.02
< 0.02
IttON (0.3)
0.39
1.35
2.47
< 0.1
0.31
0.56
HAMCAMfcSE (0.05)
0.07
0.41
0.18
0.08
0.04
0.07
SULFATE (250.)
< 15.
< 15.
< 15.
18.
17.
< 15.
TOTAL DISSOLVED S0L1US (500)
42.
33.
42.
82.
79.
71.
Z1MC (5.)
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
alkalinity
5.
10.
15.
36.
32.
27.
CALC11M
4.1
3.7
6.2
6.3
6.5
8.3
HAJUJNfcSS
20.
16.
24.
24.
26.
28.
H*UI£S1«M
0.(12
0.71
1.12
1.16
1.09
0.97
SUOlIM (20.)•
5.2
2.6
3.0
20.7
17.9
11.7
SrECltflC CUtfOIICTANCE GjHMOS)
« 25*C
66.
48.
65.
142.
137.
118.
•Die liSKFA |>ruaulgate4, am August 27, 1980. a «o41ua aonltorlng requlreaeut to bocoae
ofttsctlvo la February 11112. Ubll* no aaalauB cvttwluat level has been net fur aodlta,
tltc peaabU to IIk auwlNeatt ln41cat«« that 2Uag/l should be tlte goal.
APRIL 1981
lNt'L.
EKFL.
1ST OIST.
2ND OIST.
< 0.005
< 0.005
< 0.005
< 0.005
< 0.2
< 0.2
< 0.2
< 0.2
< 0.002
< 0.002
« 0.002
< 0.002
< 0.005
< 0.005
< 0.005
< 0.005
< 0.1
< 0.1
< 0.1
< 0.1
< 0.005
< 0.005
< 0.005
< 0.005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
<0.3
< 0.3
< 0.3
< 0.3
< 0.005
< 0.005
< 0.005
< 0.005
< 0.03
< 0.03
< 0.03
< 0.03
10.
< 10.
< 10.
< 10.
10.
2.
8.
3.
0.02
< 0.02
< 0.02
< 0.02
0.49
< 0.1
0.98
<0.1
0.06
< 0.03
< 0.03
< 0.03
15.
< 15.
< 15.
< 15.
36.
75.
65.
69.
< 0.02
< 0.02
0.04
< 0.02
4.
30.
22.
28.
4.6
4.3
3.8
5.0
14.
14.
12.
15.
0.78
0.82
0.65
0.71
4.9
22.0
21.0
20.1
62.
137.
125.
130.
-------
reservoir source and conscientious operators are responsible for this com-
pliance. Although the operators were inexperienced they did develop methods
to achieve compliance.
Site V
The operational staff at site V consisted of 3 men. The PSD employed a
consultant operator at the state health department's request due to the lack
of a class 11 license being held by any of site V's staff. The consulting
operator worked at a nearby larger water treatment plant that used a source
similar to that used by site V so he had some insight into the proper chemical
doses for coagulation and flocculation. The close proximity of the consulting
operator made him available whenever problems arose. The site V staff's
responsibilities Included plant operation, distribution system maintenance and
meter reading. The plant treated water an average of six hours per day.
' Four extended field trips of more than 1 day were made to site V (see
Figures 6 and 7) in addition to 5 one day visits. The intent of these
extended trips was to observe the facility and staff cope with anticipated
changes in influent quality.
The on site analyses performed at site V indicate consistent noncom-
pliance with the effluent turbidity standard up until approximately March 29,
1980 (Table 13, Figure 8). During the visit spanning March 17-20 recommen-
dations were made, and carried out, calling for Improved maintenance of the
facility. The recommendations included cleaning out of the flocculator of 3-4
in., of solids, thorough raking of the filters during backwashing and the
removal from the clearwell of approximately 2 in of sand and silt. The
effluent turbidity data after completion of these measures indicate com-
pliance. The influent turbidity was subject to rapid fluctuations and levels
greater than 100 ntu. During one 3-hour period the influent turbidity rose
from 17 to greater than 100 ntu and the plant effluent turbidity remained less
than 1 ntu. The free chlorine residual In the plant effluent was always
greater than 2 mg/1 and 8 out of the 10 distribution system samples had free
chlorine residuals-greater than 2 mg/1. No total coliforms were detected In
treated water samples and the highest standard plate count was 4 per ml.
The instantaneous TTHM analyse^ results were all less than 27 yg/1
(Table 14). At ambient temperature and uncontrolled pH conditions, 2 day
terminal TTHM values for the influent samples were 17.8 and 13.6 yg/1.
The analyses performed by the USEPA Indicated compliance with all of the
primary contaminant level pollutants in the treated water samples (Table 15).
The secondary MCL for manganese was exceeded in 4 of the 6 treated water
samples and the level of sulfate and total dissolved solids exceeded the MCL
in 1 of the 6 samples. The Influent water exceeded the secondary limits only
for manganese.
Compliance with the effluent turbidity standard occurred at site V as a
result of the operational staff's efforts. During the study the staff Insti-
tuted a program of regularly measuring and recording the turbidity of the
Influent and effluent and the pH of the influent, effluent and In the floccu-
41
-------
rCHEMICAL
FEED TANKS
SINK
BENCH
FLOCCULATOR
•BACKWASH
WASTE VALVES
CONTROL PANEL
TUBE SETTLERS
AND FILTERS
HIGH SERVICE
AND BACKWASH
PUMPS
EFFLUENT AND
BACKWASH VALVES
OFFICE
OFFICE
CHLORINE
CYLINDER
ROOM
Figure 6. Site V Facility layout
42
-------
CO=
ax:
FLOCCULATOR
FILTERS
BACKWASH TUBE SETTLERS
WASTE VALVES
EFFLUENT AND
BACKWASH VALVES
Figure 7. Site V Neptunt Microfloe AQ-40 200 gpm
43
-------
TABLE 13 SITE V MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
UATB
MAU
CLKAKUK1.L mLllfcNT
1ST ItlSTltlllUTIOM
2ND DISTRIBUTION
Total
Free
Total
Sid.
Free
Total
Std.
Free
Total
Std.
Cot 1 forma
CI
Collfonui
Plate
CI
Co 11 fonts
Plate
CI
Collforaa
Plate
100 ml
¦g/1
100 ml
¦1
¦b/1
100 ml
•1
¦g/l
100 al
¦1
12/0 3/79
< 4
>
2.
< 1
2
>
2.
< 1
4
>
2.
< 1
< 1
1/22/80
3.6(10
>
2.
< I
1
>
2.
< I
< 1
>
2.
< I
< 1
6/10/80
s.aoo
>
2.
< I
< I
>
2.
< 1
< 1
>
2.
< 1
< I
11/17/80
4.200
>
2.
< I
-
0.90
< 1
-
0.2
< 1
-
3/31/81
S.400
>
2.
< 1
< 1
>
2.
< 1
< 1
>
2.
< I
< 1
*-
UATM. TIME pN
Haw ClearwelI
Bf fluent
ALKALINITY
(•g/l as CaCO )
Raw CUatiMll
UflueiK
HAKSNKSS
(ag/l an CaCo.)
Haw Clearwell
Hitluent
tuiuioitv
(fttu)
Kaw Clearwell
Effluent
CI
(«g/l)
Clearwell
Effluent
12/04/79
7.5
7.7
42.
65.
150.
144.
4
1.8
1/22/80
1.1
8.1
29.
77.
117
100.
12
2.ft
3/04/60
10:4Saa
_
—
_
..
7.2
UsOSaa
-
-
-
-
-
-
-
6.3
I2s00n
-
—
-
-
-
-
-
15.4
3/03/10
tilOaa
-
-
-
-
-
-
35
1.5
3/06/80
8:3Uaa
_
_
46
2.1
L0:30a»
-
-
-
-
-
-
45
2.0
1:13|>a
—
-
-
-
-
-
35
1.9
3/17/80
9:30aa
7.1
7.6
34
60
122
117
10
1.2
lOiSSaa
-
-
-
-
-
-
-
0.5
ll;4S
-------
TABLE 13 (Cont.)
DAT* TIME pH
Haw Clear we 11
Effluent
ALKALINITY
(•g/1 aa CaC0»)
Itaw Clearwell
Effluent
o>
3/18/80
3/19/80
3/20/80
J/31/80
4/U1/80
4/02/80
8:40aa
9:30aa
9:55aa
ll:30aa
12;00b
8:45m
9:25a*
12:00u
8:25a*
10:00m
11:00a*
9:00a*
9:20a*
10:40a*
12:30|>a
l:30p*
2:30|>*
3:30j»*
8:10a*
9:45a*
10:45*.
8:00a*
9:00m
10:00a*
ll:00aa
6.9 7.1
30
76
7.6
4.6 7.5
6.9 7.5
7.3 7.3
7.5 7.6
30
40
25 49
40
29
58
50
UAMDNESS TUHUIMT* CI
(ag/l aa CaCo.) (ntu) (*g/l)
Raw Clearwell Raw Clearwell Clearwell
Effluent Effluent Effluent
108
120
82
5.7
-
-
> 100
-
-
-
-
B. 1
-
-
95
8.3
-
-
-
12.0
140
50
7.0
-
-
21
4.6
-
-
13
4.6
100
90
17
0.2
-
-
22
0.3
-
-
17
0.3
120
Ill
66
0.8
-
-
66
1.0
-
-
59
1.5
-
-
41
1.3
-
-
35
0.9
-
-
28
1.4
-
-
31
1.7
108
106
15
1.4
-
-
12
0.5
-
-
13
0.5
119 ,
120
U
0.6
-
-
7
0.3
-
-
8
0.2
-
-
8
0.1
-------
TABLE 13 (Cont.)
UATK TIME pU ALKALINITY
(ag/1 u CiCOJ
tM Clcirnell -Maw Clearwtll
Effluent Eftluent
4/03/80 8:11m. 7.3 7.6 30 43
9:00m* - -
10; lOaa - -
UiOOaa - -
12:00a - -
l;00pa - - -
4/14/80 9:00aa 7.3 J. 5 27 49
10:
11:OUaa
£ ll:45aa
o>
12: I5pa - -
l:CO|ia - -
1:45|hb - - -
3:00|ia - - -
4/15/80 0:40m - 7.4 13 39
9:10a» - -
10:00ua - -
11:00m - -
12:00b - - -
4/16/80 9:35a« 7.9 7.6 21 45
11 :00jmi - -
12:0flu - -
12:35pa - -
l:20tM - -
4/17/80 8; 30aa 7.2 7.6 29 47
9:00aa - - -
10:00m - -
ll:00|>a - -
6/10/80 7.3 6.6 40 31
11/17/80 6.2 8.6 48 68
3/31/81 7.4 7.3 28 SO
HARONESS
(ag/l ma CaCo.)
Kaw Clearwell
ISf £ luonl
TUMIDITY
(ntu)
Haw Clearwell
Effluent
CI
(»g/l)
Clearwell
Effluent
120
118
6
7
6
6
7
7
0.9
0.2
0.1
0.3
0.2
0.2
> 2.
55
68
22
17
17
37
60
100
100
100
0.4
0.3
0.4
0.6
0.6
0.5
0.8
0.5
70
90
100
70
31
32
37
0.6
0.4
0.4
0.4
0.6
> 2.
91
101
17
15
17
45
0.6
1.7
1.5
1.4
1.0
106
95
21
11
10
9
0.4
0.3
0.3
0.3
134
206
119
130
229
110
2.7
1.2
3.3
1.2
1.0
0.5
> 2.
> 2.
-------
100
90
80
70
60
50
40
30
20
10
5
0
o
o AVERAGE INFLUENT
A AVERAGE EFFLUENT
O
o
o
o
A O
A O
O
A
— O
- A A A A °
- 4 A A 4 i |
- A A A a A_A A _ A.
3 12/6/79 1/22/80 3/4-3/6 3/17-3/20 3/31-4/3 4/14-4/17 6/10 11/17 3/31/8Z
DATE
Figure 8 Site V Turbidity Removal
-------
TABLE 14 SITE V TKIHALOMETHANE ANALYSIS
INSTANTANEOUS THM
DATE
SAMPLE
chci3
CHCl2Br
CHClBr2
CHBr3
TOTAL
THM
(ng/i)
(lig/O
(Mg/l)
WO
-------
TABLE 15 SITE V CHEMICAL ANALYSES PERFORMED BY USEPA (mg/L except as noted)
FEB. 197V
JUNE 1980
NOV. 1980
HARCH 1981
MtlMAKY HCL
I NFL.
INFL,
I NFL.
EFFL.
1ST UIST.
2ND UIST.
1NFL.
EFFL.
1ST DIST.
2(0) UIST
AUiEMIC (0.05)
-
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
MAK1UH (1.)
-
0.46
<0.2
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
< 0.2
<0.2
CAIMltM (0.01)
-
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
CMUJHIUH (0.05)
-
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
FLUUtlUE (1.4 to 2.4)
-
< 0.1
< 0.1
< 0.1
< 0.1
0.2
< 0.1
< 0.1
« 0.1
< 0.1
LEAD (0.05)
-
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
HEHCUtY (0.002)
-
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< U.0005
< 0.0005
NlTltATE-N (10.)
-
-
<0.3
<0.3
< 0.3
< 0.3
0.7
0.7
0.7
0.7
SELEN1UH (0.01)
-
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
0.005
< 0.005
< 0.005
< 0.005
SILVEK (0.0S)
-
0.04
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
SECOMUAKY HO.
CHLuitlbE (250.)
-
-
< 10.
IB.
< 10.
< 10.
< 10.
< 10.
< 10.
< 10.
COLON (15 C.U.)
-
3.
6.
3.
3.
3.
2.
2.
2.
2.
curftK (i.o)
-
0.15
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
MOM (0.3)
-
0.24
0.13
< 0.1
< 0.1
< 0.1
0.12
< 0.1
< 0.1
<0.1
MAMCAMESE (0.05)
-
0.31
0.49
0.62
0.19
0.12
0.15
0.11
0.03
0.03
SULFATE (250.)
-
130.
192.
220.
222.
284.
93.
116.
110.
105.
TOTAL DISSOLVES SOLIDS (500)
-
252.
364.
390.
407.
559.
187.
236.
237.
ZlUC (5.)
-
< 0.02
0.11
0.07
0.19
0.04
0.04
< 0.02
0.40
< 0.02
ALKALINITY
-
33.
42.
42.
44.
70.
25.
37.
42.
37.
CAtjClUH
-
24.2
33.5
37.5
40.3
53.2
20.4
19.5
18.5
18.8
HAMUNESS
134.
204.
212.
220.
248.
114.
120.
110.
108.
HACMESltM
-
111.2
23.3
23.8
24.6
29.2
13.1
13.9
12.5
12.1
SODIUM (20.)*
-
17.9
28.9
31.3
30.9
71.0
8.0
24.9
33.6
22.7
Srt&lFlC CONDUCTANCE (|jHi«OS)
0 25*C
-
376.
536.
556.
576.
774.
287
268.
372.
335.
*flte USEFA proaulgattMi. on August 27, 1980, a ttodluai Monitoring requirement to becoae
etfactive la February 1902. While mo mxiaia coatulnant level heat been act for
fcodlua, the prewbl« to the ftunritmf Indicate* tbat 20ttg/l ihouU be the goal.
-------
lator. In addition, the maintenance measures recommended by the study were
incorporated into the regular maintenance routine. These efforts enabled
adequate turbidity removals from a stream source water that contained fluctu-
ating turbidities ranging up to values higher than 100 ntu.
Site R
The site R operational staff's responsibilities included plant operation,
distribution system repair and mater reading. The distribution system was
frequently in need of repairs and required the greatest part of the staff's
time. The operators typically started the plant in the morning and then went
off to repair the distribution system or read meters. The plant was left
unattended through most of it's operating time. It was in operation an
average of almost ten hours per day. A chart prepared by a previous operator
relating influent turbidity with chemical feed pump settings was often consulted
at the daily start-up of the plant. None of the three man staff was licensed,
so the PSD was required to retain a consultant operator. The consultant
operator visited site R approximately once per week.
Fourteen field trips, including 3 extended trips, were conducted to site
R (see Figures 9 and 10). The extended trips were undertaken to observe the
functioning of the treatment unit under varying influent conditions. These
extended visits revealed that the treatment plant was poorly maintained.
There was approximately 3 ft. of mud in the bottom of the flocculator. The
banks of the tube settlers had compressed or collapsed due to the weight of
built up solids that were not rinsed out in the backwash cycle. The poor
performance of the flocculation and sedimentation processes resulted in
excessive solids buildup in the filters. At the completion of a filter back-
wash cycle the backwash water was still turbid. The flocculator was cleaned
out during the week of May 12, 1980. Subsequent site visits indicate this
limited maintenance had little effect on turbidity removal.
The effluent turbidity ranged from 0.1 to greater than 100 ntu (Table 16).
The effluent turbidity was rarely in compliance with the federal standard
unless the influent turbidity was quite low. The free chlorine residual
ranged from 0.0 to greater than 2 mg/1 in the plant effluent and distribution
system samples. On 2 different occasions distribution system samples had no
free chlorine residual. No total cpliforms were detected in the plant ef-
fluent or distribution system samples examined although time did not permit
microbiological samples to be taken during periods of highest effluent tur-
bidity. Total conforms in the raw water ranged from 750 to 9,500 per 100 ml.
The standard plate count ranged from less than 1 to 2,400 per ml. The THM
determinations summarized in Table 17 indicate low levels of CTHH. The
primary and secondary MCL analyses indicate compliance in all treated water
samples with the exception of manganese in 2 samples (Table IS). The influent
water exceeded the secondary limits for color, iron, and manganese.
The above data demonstrate that the site R treatment facility did not
remove a sufficient amount of turbidity on most site visits. Effluent turbi-
dity measurements of 1.5 ntu or less occurred only when the influent turbidity
was less than approximately 20 ntu. The high effluent turbidity valves were
due to a lack of operator attention, especially insufficient maintenance on
the flocculator and tube settlers. A lack of operator skill and the required
50
-------
SINK
BENCH
BACKWASH
WASTE LINES
=r a
CHEMICAL FEED
TANKS
FLOCCULATOR
SETTLER-FILTER
TANKS
CHEMICAL
STORAGE
CHLORINE
CYLINDER
ROOM
Co7"
i—i
DESK
CONTROL
PANEL
BACKWASH
•PUMPS
-HIGH SERVICE
PUMPS
Figure 9. Site R Facility layout
51
-------
RAP© MIX
ZONE
—
iiiiiiiiiiilfiiii
!i ihi l11 i111
11 i itih i It Mi
.11 It Ml It, Lt III
—
7! ] I
ill
1! 1
11
1.1 M 1
!!! i i; i m ! i;
i M1! i 1! m ! i
''! 1' 11! 1!!!
~tr
FLOCCULATION
ZONE
miiii
Ml
EFFLUENT
ZONE
!! 11
BACKWASH
WASTE VALVE
TUBE
SETTLERS
-FILTER
OVERFLOW
PIPE
'iitiil
nrrttuni
.iiiMiij! !! »!i ill I
\
BACKWASH
TROUGH
1
K1
II
\
I!
11
X
Figure 10. Sice R Neptune Microfloc AQ-112 560 gpm
52
-------
TABLE 16 SITE R MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
UATE RAM CLEARMELL EEFLUEHT 1ST UISTRIbUTIOH 2Hl> DISTRIBUTION
Total
Fee*
Total
Std.
Free
Total
Std.
Free
Total
Std.
CollfotM
CI
Coliforas
Plate
CI
Collforaa
Plate
CI
ColIfora#
Plate
100 .1
ag/1
100 Ml
al
ag/1
100 al
al
•tj/1
100 al
al
7/17/79
4.OU0
0.2
< I
_
0.0
< I
_
1.1
< 1
_
8/14/79
6.500
1.9
< |
0.1
< 1
2.400
1.2
< I
< 1
iO/Ol/79
7.100
1.9
< 1
7
0.8
< I
2
1.8
< 1
20
10/30/79
6.500
1.9
< 1
< i
0.9
< 1
< 1
-
-
-
12/03/79
750
> 2.
< 1
1
>
2.
< I
< 1
> 2.
< 1
< 1
1/23/80
5.700
0.6
< 1
5
1.6
< I
8
0.6
< 1
2
6/09/80
9.500
2.
< 1
1
>
2.
< 1
< I
0.0
< I
600
11/18/80
5,700
0.2
< 1
2
>
2.
< 1
< 1
1.8
< 1
< 1
3/30/81
8,800
> 2.
< 1
3
>
2.
< 1
2
1.4
< 1
2
DATE TIME |»U
Raw CleanMli
Effluent
ALKALINITY
(ag/l «a CaCO.)
Haw Clearwell
Effluent
HARDNESS
(«g/l a« CaCo.)
Raw Clearwell
Effluent
TURBIDITY
(ntu)
Raw
Clearwell
Effluent
CI
(-8/1)
Clearwell
Effluent
5/11/19
7/20/79
11/14/79 7.1
10/01/79 7.4
10/30/79 7.2
12/05/79 7.3
1/23/8(1 7.2
2/(14/80 10:30aa
ll;15aa
l:00pa
2/05/80 6. a
2/06/80 7.1
7.1
6.6
7.8
8.2
6.8
6.7
6.9
7.4
244.
34.
49.
43.
30.
20.
48.
43.
54.
32.
30.
59.
62.
22.
18.
29.
52.
148.
100.
140.
112.
104.
122.
130.
53.
120.
138.
94.
142.
112.
80.
118.
133.
39.
40.
27.
6.0
3.8
73.
3.7
3.5
3.5
3.8
6.0
0.2
3.8
2.6
2.4
1.2
0.1
11.
0.1
0.1
0.2
0.3
0.5
2.
1.9
1.9
1.9
0.6
0.6
2.
-------
TABLE 16 (Cont.)
DATS TIME pU ALKALINITY
(*g/l " CaCO.)
Raw Clearwell Raw Clcuwall
Effluent Effluent
4/28/80 8:50aa 7.2 8.4 il. 40.
IO:UOm - -
U:00aa - -
12:0Uu - - - -
liOUya - -
2;OOp« - -
3: Itya - -
4:001* - -
4: 3U|>a - - -
4/29/SO 8:304a 6.2 7.2 il. 3S.
9:30aa - -
10:30m - -
ll:30a« - -
12: tOpa - -
2:30pm - -
3:301* - -
4/30/80 9:00a. 6.8 7.6 - 40.
5/01/80 9:00*a - -
I0:00sm - -
ll:0Uaa - - -
12:00b - - -
5/12/80 9:0Uaa 7.1 7.3 30. 50.
10:00a* - -
11:
12:0(h>
l:00pa
HARDNESS TUKBIDITY CI
(¦g/l as CaCo.) (otu) (mg/l)
Haw Clearwell Raw Clearwell Clearwell
Effluent Effluent Effluent
58.
58.
>
100.
28.
-
-
-
24.
-
-
72.
22.
-
-
65.
24.
-
-
64.
13.
-
-
63.
9.3
-
-
62.
7.5
-
-
56.
13.1
-
-
56.
7.0
70.
59.
_
5.1
-
-
27.
5.1
-
-
26.
3.0
-
-
24.
2.0
-
-
24.
1.8
-
-
28.
1.7
-
-
20.
4.9
60.
60.
>
too.
3.7
-
-
>
100.
39.
-
-
>
100.
80.
-
-
>
too. >
100.
_
_
>
100.
60.
-
-
>
100.
39.3
-
-
>
100.
15.6
-
-
-
11.
139.
136.
17.5
4.6
-
-
9.3
4.7
-
-
6.2
3.8
-
-
5.9
1.1
-
-
7.2
0.6
-
-
7.0
0.5
-
-
6.4
0.4
2.
1.4
-------
TABLE 16 (Cont.)
DATE TIME pH ALKALINITY
(¦l/l as CaCO..)
Raw Clearwell taw Clearwell
Efflaent Effluent
6/02/ItO 7.7 7.7 48. 48.
6/03/80 8:50aa 7.8 7.4 46. 58.
10:00u* - -
1tiOOaa - -
12:00a - -
i:00|Mi - -
2:OSpa - - -
liOiya - -
4:0Upa - -
6/04/80 9:00m 7.0 7.4 45. 60.
IO:OU 2.
0.2
81.
88.
8.2
1.04
> 2.
-------
TABLE 17 SITE K TKIHALOMKTiiANE ANALYSIS
INSTANTANEOUS TUM
DATE SAMPLE
CHCl.
(Ug/1)
CUCl^Br
(yg/i)
CHClBr,,
(yg/U
CHBr3
(Pg/D
TOTAL
THH
(Hg/i)
10/30/80 Effl.
06/09/80 E€fl.
06/09/80 Effl.
14.5
0.5
4.3
0.5
N.l).
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
15.0
0.5
4.3
TERMINAL TUM (2 DAY)
DATE SAMPLE
CHLORINE
DEMAND
(»g/l)
CHCl3 CHCl^Br CHClBr2 CHBr^
(Mg/1) (Pg/l) (pg/1) (jJg/1)
TOTAL
TUM
(Mg/1)
06/09/80 Inf1. 1.55
06/09/80 InfI. 0.62
28.8
64.4
3.7
13.6
N.D.
1.9
N.D.
N.D.
32.5
79.9
N.D. - None Detected
-------
TABLE 18 SITE R CHEMICAL ANALYSES PERFORMED BY USEPA (rng/L except as noted)
tUM. 1979 June 1980 OCT. 1980 HA*CM 1981
muuiii NO.
1WL.
IttfL.
em.
INFL.
tt»L.
1ST 01ST.
2N0 OIST.
1MH-.
tux.
1ST OIST.
2N0 D1ST
**stm£ to. OS)
< O.OOi
< O.OOi
< 0.005
< O.OOi
<
O.OOi
< O.OOi
< O.OOi
< 0.005
< O.OOi
< O.OOi
< O.OOi
•WIW (1.)
0.49
0.2
0.37
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
uuaw (u.ot)
< 0.002
< 0.002
« O.OOi
< 0.0O2
<
0.002
< 0.0O2
< 0.002
< 0.002
« 0.002
< 0.002
< 0.002
CWUMIIM (O.Oi)
< O.ooi
< O.OOi
< O.OOi
« O.OOi
<
o.ooi
< 0.005
< O.OOi
< 0.005
< O.OOi
< 0.005
< O.OOi
tiUUIIll*. (I.« ta 2.4)
< 0.1
< 0.1
< 0.1
< 0.1
«
0.1
« o.l
< O.l
< 0.1
< 0.1
< 0.1
< O.l
LCAU (0.0S)
0.094
«. 0.005
< 0.005
0.004
«
O.OOi
< 0.005
< O.OOi
< 0.005
« 0.005
< 0.005
« O.OOi
HUUU (A. 002)
0.0008
0.0009
< O.OOOi
< 0.0005
<
0.0005
< 0.0005
< O.OOOi
< O.OOOi
< 0.0005
< O.OOOi
< 0.0005
MTMATE-N (iO.)
o.;
-
-
<0.3
<
0.3
<0.3
« 0.3
0.9
0.9
0.7
0.7
ULLAfclUH (0.01)
< 0.001
< O.OOi
< 0.005
< 0.005
<
0.0U5
< O.OOi
< O.OOi
< O.OOi
< O.OOi
< O.OOi
< O.OOi
sava (o.oi)
< 0.03
« 0.0)
< 0.0)
< 0.03
<
0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.03
< 0.0)
tiUAINUAMt MCL
CMLUtlUC (250.)
180.
-
-
< 10.
10.
10.
12.
< 10.
< 10.
< 10.
< 10.
C0UJK (IS C.B.)
4.
3.
3.
20.
).
3.
3.
2.
2.
2.
2.
COM** (1.0)
l.ii
0.0*
< 0.02
< 0.02
0.03
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
<0.02
UUMI (0.J)
2.11
0.41
« 0.1
1. It
0.24
< 0.12
<0.1
0.29
0.1
0.11
0.11
wim tufit (o.oi)
A. 22
0.20
0.09
0.40
< 0.03
< 0.03
< 0.03
0.12
0.01
0.24
<0.03
SULFATE (2Mi.)
110.
14.
90.
13V.
184.
184.
180.
78.
78.
78.
70.
total iissoua
SUUIB (400)
384.
154.
1*4.
24V.
387.
388.
3)4.
Ii8.
141.
liO.
142.
ZINC (i.)
0.2)
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
0.38
< 0.02
< 0.02
< 0.02
0.20
alkalinity
0.
20.
29.
38.
70.
70.
43.
22.
20.
20.
17.
CALCIUM
1 A.)
14.4
14.9
25.7
32.)
32.0
32.8
14.4
17.0
li.5
14.2
MAIUMMi&>
100.
¦4.
M.
130.
152.
li2.
148.
90.
92.
92.
80.
HAOttSIUt
11.
11.0
10.4
14.8
14.9
14.8
18.7
9.i8
9.44
9.87
9.20
SUtUM (20. ) A
3i.
9.
20.9
21.1
45.0
43.5
52.0
10.2
10.2
10.4
9.4
sruuiric COMOUCTAHCC
(laiiMKS i 2i*C)
14*9.
23».
292.
401.
i84.
i88.
542.
2i5.
2ii.
2ii.
224.
•am HiUf4 promulgated. m iugiMI 2}. ItMW, a aodiua KMitollug [)H|uUwMtA( to Ihccumh
•flulln la febrnary IM2. Uktlt ma aaalaua cwlnalaut lavel baa baea Ml far audlua,
*ba |»ciuat(U lu the aaaadaeiiia MIcum (bat 2Qmt/l abould Iw ilw gaal.
-------
repair of the distribution system caused a low priority to be attached to the
operation of the treatment plant. The source water quality vas at times
extremely poor with an estimated maximum influent turbidity of well over 500 ntu.
Site P
Site P (see Figures 11 and 12) employed a part-time operator since they
were unable to find a qualified full-time person. The chairman of the PSD
also operated the plant some of the time. The operator's responsibilities
included plant operation, distribution system maintenance and meter reading.
The operator was present approximately 2 hours per day although the plant
operated an average of 13.7 hours per day. During the 2 hours the chemical
feed solutions were replenished as necessary and the routine analyses were
performed.
The effluent turbidity was greater than 1 ntu on 6 of the 9 site visits
(Table 19) although the influent turbidity never exceeded 17.2 ntu. The pH of
the source was always acidic, ranging from 4.5 to 5.9. The effluent pH was
acidic in 7 of the 8 samples tested. The free chlorine residual in the plant
effluent and distribution system samples ranged from 0.0 to greater than 2.
mg/1. No total coliforms were detected in any treated water samples and the
standard plate counts of the treated water samples ranged from less than 1 to
20 per ml. The source water total coliforms ranged from 2 to 1500 per 100 ml.
Effluent TTHM's were low [(22.2 and 34.5 us/l) (Table 20)]. A distribu-
tion sample had a TIHM concentration of 214 yg/1. The primary and secondary
maximum contaminant level analyses performed by USEPA Indicated compliance in
all the treated water samples (Table 21). The influent water exceeded only
the secondary limits for manganese.
The data from site P indicate a lack of operator presence to be the cause
of the turbidity standard being exceeded. The facility had a higher
average daily operating time than any of the other plants studied and only had
a part-time operator. The plant was typically left in an automatic mode 24
hours per day. The chemical feed lines were removed from their injectors in
the Influent pipe to discharge into the top of the rapid mix chamber because
the injectors would occasionally clog during the long hours of unattended
operation. This move negated the use of the rapid mix chamber and in line
chemical mixing. The operator was never observed adjusting chemical doses to
effect better coagulation and flocculation. The low effluent pH bears out the
apparent lack of control of the coagulation chemicals.
Site G
The site C treatment plant was different from the others studied in that
it consisted of a solids contact upflov clarifier and 2 rapid sand filters
(see Figures 13 and 14). The operators maintained the pH in the solids con-
tact unit at 6.1 and tried to keep the sludge blanket well defined and low.
The sand filters had been built with rate of flow control valves but the
operators Installed hand controlled valves instead. The filter backwash was
carried out manually rather than by a cam timer.
58
-------
ABOVE GRADE
CLEARWELL
TREATMENT UNIT
EFFLUENT AND
BACKWASH PUMPS.
SINK
HIGH SERVICE
PUMPS
BENCH
Figure 11. Sice P Facility layout
59
-------
RAPID MIX-
CHAMBER
INFLUENT"
PIPE
FLOCCULATOR
ITf
"
11
Hi
"!
ill
WI.
III!!!
i! I'1!
Mill!
Lit II LI
D
''I
111 n it 1.1
ji
ii
i!i
TUBE
SETTLERS
FILTER
BACKWASH
ORAIN PIPE
Figure 12. Site P Neptune Microfloc WB-133 100 gpm
60
-------
TABLE 19 SITE P MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
DATE
RAW
CLEARWELL
EFFLUENT
1st distribution
2ND DISTRIBUTION
Total
Pre*
Total
St4.
Free
Total
Std.
Free
Total
Std.
Co 11 tor**
CI
Colifo
nut Plate
CI
CaUfonm
Plate
CI
Collforaa
Plate
100 al
¦k/i
100 al
¦1
afc/1
100 al
•1
•g/L
100 al
•1
6/11/79
90
0.0
< 1
7
0.0
< 1
20
0.0
< 1
8
8/29/79
590
0.5
< I
< 1
0.8
< I
1
0.1
< 1
5
10/13/74
21
0.6
< 1
11
0.2
« 1
2
-
-
-
11/13/79
30
1.0
< 1
< 1
1.5
< 1
< 1
-
-
-
1/07/80
2
> 2.
< 1
< 1
> 2.
< 1
1
> 2.
< 1
< 1
6/23/80
470
> 2.
< 1
8
> 2.
< I
< 1
-
-
-
10/28/8U
57
1.3
< 1
-
1.5
< I
-
-
-
-
4/13/81
1,500
> 2
< 1
-
0.63
< I
-
0.32
< 1
-
UATK
P«
ALKALINITY
HARDNESS
TURBIDITY
CI
(¦ft/1
as CaCOj)
(ag/l
as CaCo^)
(ntu)
(>8/1)
Saw
Clearwell
Raw
Clearwell
Raw
Clearwell
Raw
Clearwell
Clearwell
IffllMlt
Effluent
Effluent
Effluent
Effluent
6/11/79
4.5
5.4
2.
19.
42.
45.
12.
0.8
0.0
8/03/79
4.5
6.8
2.
18.
20.
20.
4.4
2.4
0.3
8/29/79
-
6.9
6.
20.
25.
30.
-
7.0
0.5
10/15/79
-
-
1.
12.
10.
14.
3.5
1.5
0.6
11/13/79
5.9
6.9
4.
36.
22.
24.
2.0
0.1
1.8
1/U7/80
5.2
8.1
0.
20.
25.
28.
1.2
0.5
> 2.
6/23/80
5.5
6.6
9.
9.
21.
28.
15.6
9.7
> 2.
10/28/80
5.0
6.9
2.
8.
40.
42.
3.1
2.2
1.3
4/13/81
5.1
5.2
1.
1.
19.
24.
17.2
1.9
> 2
-------
TABLE 20 SITE P TKIHALOMETHANE ANALYSIS
INSTANTANEOUS TllM
DATE SAMPLE
chci3
(Mg/1)
CUCl^Br
(»ig/l)
CliClBr,
(Wg/D
CHBr3
(Mg/D
TOTAL
THM
-------
TABLE 21 SITE P CHEMICAL ANALYSES PERFORMED BY USEPA (mg/L except as noted)
raUOKY Htx
It#. 1979
INPL.
JUNK 19110
mi..
1NKL.
OCT. tWO
Et'FL. 1ST 0IST.
2NO uiST.
I NI L.
miL 1981
EWL. 1ST 0IST.
2ND 01ST.
AKSEM1C (0.05)
< 0.005
<
0.005
<
0.005
<
0.005
<
0.005
-
<
0.005
<
0.005
<
0.005
<
0.005
BAMIM (1.)
0.28
0.52
0.33
0.21
0.22
-
<
0.2
<
0.2
0.23
0.21
CAUH1UH (0.01)
< 0.002
<
0.002
<
0.002
<
0.OU2
<
0.002
-
<
0.002
<
0.002
<
0.002
<
0.002
CUMUMIUM (0.05)
< 0.005
<
0.005
<
0.005
<
0.005
<
0.005
-
<
0.005
<
0.005
<
0.005
<
0.005
H.UOKlUfc (1.4 to 2.4)
< 0.1
<
0.1
<
0.1
<
0.1
<
0.1
-
<
0.1
<
0.1
<
0.1
<
0.1
LEAD (0.05)
< 0.005
0.005
<
0.005
<
0.005
0.000
-
<
0.005
<
0.005
0.013
0.019
HUtCUtV (0.002)
< 0.0005
0.0008
0.0005
<
0.0005
0.0005
-
<
0.0005
<
0.0005
<
0.0005
<
0.0005
MITKATE-N (10.)
< 0.3
-
<
0.3
<
0.3
<
0.3
-
<
0.3
<
0.3
0.3
0.3
SU-ENIUt (0.01)
< 0.005
<
0.005
<
0.005
<
0.005
<
0.005
-
<
0.005
<
0.005
<
0.005
<
0.005
SILVER (0.05)
< 0.03
*
0.03
<
0.03
<
0.03
<
0.03
-
<
0.03
<
0.03
<
0.03
<
0.03
SbCuNUAkY MCL
CUUNtME (250.)
<10.
-
40.
40.
45.
-
<10.
<10.
2ft.
20.
a*
count (15 C.U.)
3.
5.
3.
3.
3.
-
5.
3.
3.
3.
w
cur tut (i.o)
0.11
0.15
<0.02
<0.02
0.20
-
<0.02
<0.02
0.16
0.05
HUM (0.3)
0.20
0.57
< 0.1
0.16
0.1ft
-
0.35
<0.1
0.19
0.1ft
HANCANKSK (0.05)
0.11
0.19
0.20
< 0.03
<0.03
-
0.15
<0.03
<0.03
<0.03
SULFATE (250.)
< 15.
< 15.
< 15.
< 15.
< 15.
-
< 15.
15.
< 15.
< 15.
TOTAL DISSOLVED SOLIDS (500)
49.
45.
113.
121.
115.
-
42.
54.
93.
75.
Z1MC (5.)
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
-
0.03
<0.02
0.03
<0.02
ALKALINITY
1.
4.
1.
5.
6.
—
1.5
1.
2.
2.
CALC1IM
4.9
4.4
10.1
11.5
11.5
-
4.7
6.6
10.1
ft.O
HAttOMESS
11.
20.
39.
40.
40.
-
1ft.
22.
34.
2ft.
HACMES11M
1.12
0.45
1.(15
I.H6
1.89
-
1.04
1.06
1.4ft
1.2ft
SUOIUM (20.)*
3.9
3.7
3«.
20.3
21.2
-
4.ft
5.8
15.6
11.0
SPECIFIC CONDUCTANCE (pHUOS)
« 25*C
75.
70.
204.
21ft.
21ft.
-
75.
95.
175.
133.
i
*Ttee IKtft pcoaulgatisd, on August 27, 19MU, a wdlw Monitoring r^utmunt to Imcmw
*tt*ctliM la February 1112. Uhil* no aulau coataalfetat Uvul Im« beta ««( fur «o4tM,
lb* f*«Ml>l* to tbe wwnil—ntw Utlcitc* tbat 20ag/l ohoulil bts tlMt |»*l.
-------
CHLORINE
CYLINDER
ROOM
SINK
UPFLCW CLARIFIER
CHEMICAL FEED
TANKS
SANO FILTERS
HIGH SERVICE ANO
BACKWASH PUMPS
DESK
CHEMICAL
STORAGE
Figure 13. Sic« C Facility layout
64
-------
SAND FILTERS
SOLIDS CONTACT
UPFLOW CLARIFIER
EFFUJEMT
FILTER INFLUENT AND
BACKWASH DRAIN PIPE
FLUME
INFLUENT
FILTER EFFLUENT
AND BACKWASH PIPE
Figure 14. Site
C Pernutit 200 gpm
-------
The two operators' responsibilities consisted of plant operation, distribu-
tion system maintenance, and maintenance of several package wastewater treat-
ment plants also located in the park. The water plant operated an average of
almost 5 hours per day.
The effluent data indicate that the turbidity MCL was met on all 9 site
visits (Table 22). The influent turbidity ranged from 1.2 to 12.6 ntu. The
operators kept a low free chlorine residual in the clearwell, between 0.1 and
1.0 mg/1, due to the small size of the distribution system. There was no free
chlorine residual in 11 of the 18 distribution system samples tested and no
total conforms were detected in the treated water samples. The raw water
total conforms ranged from 25 to 1400 per 100 ml. The standard plate count
ranged from less than 1 to 2,700 per ml for the effluent and distribution
system samples.
Trihalomethane analyses were performed on samples taken on 3 different
site visits (Table 23). The results though not consistant Indicate some
concentrations of TTBM greater than the 100 ug/1 prescribed by the USEPA for
systems serving 10,000 or more population. The raw water terminal TTHM
analyses results were 332.3 and 351.6 yg/1 reflecting the high concentration
of precursor material present in the source river water.
The primary and secondary MCL analyses performed by USEPA indicate
compliance in all the treated water samples (Table 24). The raw water ex-
ceeded only the secondary limits for color, iron, and manganese.
Site C successfully met all the drinking water standards on all site
visits. This result was a product of sound operation and a consistently
good quality influent water. The facility was monitored frequently and was
never left operating unattended.
66
-------
TABLE 22 SITE C MICROBIOLOGICAL ANALYSES AND WATER QUALITY CHARACTERISTICS
DATE
Total
Oollfonw
100 ad
CLEAKWCU. WKLUfcHT
Free
CI
¦g/1
Total
Callfiiai)
100 Ml
Std.
Plate
ad
1st msriti&trriON
Free
CI
•u/l
Total
Colt for—
100 Ml
Std.
Plate
Ml
2ND UISTHIBUTION
Free
CI
Mg/1
Total
Conform
100 Ml
Std.
Plata
6/00/79
7/31/79
It/27/79
10/16/79
U/14/79
1/07/80
6/23/80
10/27/80
4/14/til
120
77
390
66
490
640
25
1400
260
0.7
0.1
0.2
0.7
0.4
0.6
1.0
0.5
0.2
650
< I
< 1
0.0
0.0
0.1
0.1
0.2
0.1
0.3
0.0
0.0
2700
10
280
5
< 1
150
0.2
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
100
S6
35
2000
2
1
DATE
pH
ALKALINITY
UAKttHESS
TURBIDITY
CI
(¦8/1
as CaCO^)
(Mg/1 an L'aCOj)
(ntu)
(»g/l)
Haw
Clearwel1
Raw
Clearwell
ttaw Clearwell
Haw
Clearwell
Clearwell
Effluent
Effluent
Ef fluent
Kf flueat
Effluent
6/08/79
6.8
6.6
20.
47.
28 . 23.
8.5
0.3
0.7
7/31/79
6.2
6.6
22.
50.
30. 26.
6.2
0.2
0.1
8/27/79
6.4
7.0
18.
62.
24. 21.
1.2
0.3
0.2
10/16/79
-
-
12.
72.
22. 20.
1.6
0.1
0.7
11/14/79
6.6
9.3
18.
80.
29 . 28.
2.2
0.1
0.4
1/07/80
6.5
7.0
20.
50.
30. 30.
4.0
0.1
0.6
6/23/80
6.2
8.9
19.
88.
29. 22.
12.6
0.7
1.0
10/27/80
7.2
8.2
18.
81.
31. 27.
5.2
0.2
0.6
4/14/81
6.3
7.2
10.
39.
23. 20.
2.2
0.2
0.2
-------
TABLE 23 SITE C TRIHALGMETHANE ANALYSIS
INSTANTANEOUS THM
DATE SAMPLE
chci3
(Mg/1)
CItCI2&r
(pg/l)
CUClBr,
(lig/1)
CHBr3
(pg/1)
TOTAL
THM
(pg/1)
10/Ito/79 Etfl.
6/23/80 Effl.
10/27/80 Effl.
10/27/80 1st Dist.
10/27/80 2nd Diet,
112.
0.06
77.0-
3.3
266.
1.3
N.D.
23.7
13.0
10.3
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
113.
0.1
101.
16.3
276.
TERMINAL THM (2 DAY)
DATE
SAMPLE
CHLORINE
DEMAND
(ng/1)
CHClj CHCI2Br CHCIBr2 CHBr^
(Mg/1) (pg/1) (pg/1) (Pg/l)
TOTAL
THM
(pg/1)
6/23/80 Infl. 4.4
6/23/80 Infl. 4.3
326.
340.
4.3
11.6
2.0
N.D.
N.D.
N.D.
332.
352.
N.D. - None Detected
-------
TABLE 24 SITE C CHEMICAL ANALYSES PERFORMED BY USEPA (rag/L except as noted)
FEK. 1979 JUNE 1980 OCT. 1980
rilllUtH MCL
I NFL.
1NFL.
1NFL.
EFFL.
1ST 01ST.
2ND OIST.
AKSfcNlC (0.05)
< 0.005
< 0,005
< 0.005
< 0.005
< 0.005
< 0.005
UHUM (1.)
0.21
< 0.2
< 0.2
0.20
< 0.20
< 0.20
CAIM1UM (0.01)
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
< 0.002
OtttUUUM (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
FLOUKlUg (1.4 to 2.4)
< 0.1
< 0.1
<0.1
< 0.1
< 0.1
< 0.1
LEAD (0.05)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
HtRCUHt (0.002)
0.0005
0.0013
0.0012
< 0.0005
< 0.0005
0.0007
M1TKATK-N (10.)
< 0.3
-
* 0.3
< 0.3
< 0.3
< 0.3
SELCNIUM (0.01)
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
< 0.005
S1LVKK (0.05)
< 0.03
0.04
< 0.03
< 0.03
< 0.03
< 0.03
S bOiHUA.IL Y MCL
CUUMllUt (250.)
<10.
-
< 10.
< 10.
< 10.
< 10.
COLON (15 C.U.)
18.
25.
40.
3.
3.
3.
C0PFE8 (1.0)
0.04
0.12
< 0.02
< 0.02
< 0.02
< 0.02
IKON (0.3)
0.22
1.06
0.52
< 0.1
< 0.1
< 0.1
HANCANESti (0.05)
0.07
0.20
0.10
< 0.03
< 0.03
< 0.03
SULFATE (250.)
< 15.
< 15.
15.
47.
44.
43.
TOTAL HISSOLVED SOLIDS
(500)
55.
40.
60.
174.
172.
179.
ZINC (S.)
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
ALKALINITY
6.
17.
15.
78.
80.
92.
CALC1IM
4.#
6.3
10.
8.0
9.9
10.8
NAKMI£SS
16.
21.
30.
28.
32.
34.
MAGNESIIM
0.49
0.66
1.10
1.16
0.65
0.60
SO01IM (20.)*
1.
1.
1.9
53.5
49.5
53.0
SPECIFIC CQNOOCTANCK (|iMttOS)
«25*C
39.
52.
78.
294.
287.
302.
*The USU*A promulgated, oa August 27, 1980, * aodlua Monitoring requlreaeat to becoae
effective la February 1982. While no uiliua contaalnant level has been set for todlua,
tbe |««aabl« to tbe aauuuteenta indicates tluit 20k»g/l should be the goal.
AMUL 1981
INFL.
EFFL.
1ST OIST.
2NO U1ST.
< 0.005
< 0.005
< 0.005
< 0.005
< 0.2
< 0.2
<0.2
<0.2
< 0.002
< 0.002
< 0.002
< 0.002
< 0.005
< 0.005
< 0.005
< 0.005
< 0.1
< 0.1
< 0.1
< 0.1
< 0.005
< 0.005
< 0.005
< 0.005
< 0.0005
< 0.0005
< 0.0005
< 0.0005
< 0.3
< 0.3
< 0.3
<0.3
< 0.005
< 0.005
< 0.005
< 0.005
< 0.03
< 0.03
< 0.03
< 0.03
10.
< 10.
< 10.
< 10.
20.
3.
3.
3.
< 0.02
< 0.02
< 0.02
< 0.02
0.31
< 0.1
<0.1
< 0.1
0.07
< 0.03
< 0.03
< 0.03
15.
29.
28.
29.
35.
98.
104.
116.
< 0.02
< 0.02
< 0.02
0.06
7.
37.
46
59.
5.7
6.0
7.9
13.5
16.
20.
24
32.
0.69
0.68
0.60
0.68
1.2
31.
31.4
34.0
49.
175.
189
211.
-------
SECTION 7
SUMMARY
Six water treatment facilities selected for field research had varied
success in their turbidity removals. Plant C met the turbidity requirement of
1 mtu on all site visits. Two other facilities (sites V and 1) met the
turbidity standard on nearly all occasions: plant W exceeded the limit once,
and plant T exceeded it twice. These three facilities had low turbidity
sources (1.2 to 29.7 ntu) and quality operators.
The other three participating plants (V, R and P) met the turbidity
standard on fewer than half of the visits made to them. The difficulties in
performance involved the variability and quality of the source, the short
detention times inherent in the design of the treatment units, and the lack of
skilled operators with sufficient time to devote to treatment. The Site V
data appear to Indicate improvement. The first eight daily values obtained at
this site (encompassing a 4 month period) show noncompliance with the stand-
ard. Daily average turbidities for the last 11 sampling days (encompassing an
8 month period) indicate compliance with the 1-ntu standard, although some
individual values exceeded that limit. Improved operational methods and some
needed maintenance may be partially responsible for this better performance.
Difficulties in turbidity'removal at Site R were largely caused by the high
and variable turbidity (3.5 to >100 ntu) of the source water and the staff's
outside responsibilities, which required too much of their time. The influent
turbidity data of Site P are consistently low (17.2 ntu maximum), Indicating a
treatable source. A lack of operator attention because of employment of a
part-time operator is responsible for that site's noncompliance.
The treated water total coliform determinations from all 6 plants shoved
no total colltorms, with the exception of a distribution system sample taken
at a residence. Total colifora determinations on rav water samples from the
six water treatment plants varied up to 10,000 total collforms per 100 ml.
Two of the three facilities using river sources had the highest total coliform
densities. The densities of total coiiforms for the source rivers of these
two plants were typically between 1,000 and 10,000/100 ml. The plants using
impoundments for their source had raw water total coliform densities approxi-
mately one order of magnitude less than this range.
The treated water standard plate counts for all six facilities were low.
Thirty percent of the samples had counts that were 1/ml or lower.
Sixty-eight percent of the samples showed densities of 10/ml or lower. The
highest standard plate count was 2700/ml.
The low standard plate counts and the absence of total conforms in the
treated water examined indicates that all six water treatment facilities
70
-------
produced adequately disinfected water.
The analyses performed by the USEPA Drinking Water Research Division for
the primary and secondary maximum contaminant level pollutants show that all
primary regulations were met in all influent and effluent samples. Five ef-
fluent samples had manganese concentrations greater than the secondary maximum
contaminant level prescribed by the USEPA. Also, two treated water samples
exceeded the iron concentration recommended as a secondary maximum contaminant
level. The results of the effluent and distribution system analyses revealed
that IS of 18 treated water samples exceeded 20 mg/1 sodium.
Note that the operators of these facilities were not trying to control
sodium, manganese, or iron at the time these samples were collected. The
major concerns for the operators were turbidity removal and adequate disin-
fection.
Four of the six plants studied had at least one treated water instan-
taneous trihalomethane (THM) sample with a total THM concentration greater
than 0.L0 mg/1. The small size of these water systems precludes them from
having to comply with any present THM regulations, The point of chlorination
and often the large free chlorine residuals ( >2. mg/1) detected in the
treated water contribute to these levels of THM. All six of the plants were
originally equipped with pre- and post-chlorinatlon capabilities, but during
the study, all of the plants practiced prechlorination that would contribute
to high THM.
The three facilities, sites C, T, and W, that were most successful had
competent operational staffs who devoted sufficient time to water treatment.
These staffs all had knowledge of water treatment or great familiarity with
their respective plant and dedication to their work. These staffs were char-
acterized by frequent monitoring of the influent and effluent quality. Im-
provement of the water quality at site 7 came from increased maintenance and
more frequent sampling of water through the plant. The staff at site R lacked
adequate knowledge of and time to devote to water treatment. Distribution
system maintenance requirements kept this staff from properly maintaining and
monitoring their plant. The smail percentage of time spent by the operators
at site P resulted in poor effluent quality even though the influent turbidity
was quite low.
Four of the plants studied had consistent source turbidities. Three of
these were the result of using surface impoundments. Three of the 4 sites
with uniform quality source waters produced effluent that consistently met the
effluent turbidity standard. Although the source water at site P was a reser-
voir and the influent turbidity was not observed to be above 20 ntu, inade-
quate operation at this plant resulted in an effluent frequently above 1 ntu.
The stream source quality at site 7 was variable and at times greater than 100
ntu. The average 6 hours of operation per day at site 7 allowed the staff to
avoid some periods of highest turbidity. The site R stream source had turbi-
dity peaks, greatly in excess of 100 ntu, that according to product literature
and a manufacturer's representative could not be adequately treated at the
design capacity of the treatment unit. Sites 7 and R caused the state health
department's engineers to state that they will be reluctant to approve plans
for a similarily designed unit to be installed on a highly variable stream
source in the future.
71
-------
1
2
3
4
5
6
7
8
9
lO-
ll
12
13
REFERENCES
Interim Report of the Ad Hoc Committee to Define and Investigate
Problems in Small Water Utilities, (Amer. Water Works Assoc. 1980).
Community Hater Systems: Financial Aspects of Compliance vith Interim
Primary Drinking Water Regulations-Draft- (USEPA Office of Drinking
Water, 1980).
Recommended Standards for Water Works (Ten States Standards), (Albany,
New York, Health Education Service, 1972).
ASCE, AWWA, and CSSE. Water Treatment Plant Design (New York; Amer.
Water Works Assoc., Inc. 1969).
Gemmell, R.S. "Mixing and Sedementation," Water Quality and Treatment,
Amer. Water Works Assoc., Inc. (New York; McGraw-Hill Book Co.,
1971).
Amirtharajah, A. "Design of Rapid Mix Units," Water Treatment Plant
Design, Ed. by R.L. Sanks, (Ann Arbor, Mich.; Ann Arbor Science
Publ., 1979).
Vrale, L. and R.M. Jorden. "Rapid Mixing in Water Treatment," J. Am.
Water Works Assoc. 63: 52-58 (1971).
Ger, A.M. and E.R. Hoiley, "Comparison of Single-Point Injections in
Pipe Flow," J. Hyd. Div. ASCE. 731-746 (1976).
Argaman, Y. and W.J. Kaufmani "Turbulence and Flocculation," J.
San. Eng. Div. ASCE. 223-241 (1970).
Hudson, H.E. Jr. and J.P. Wolfner. "Design of Mixing and Floc-
culating Basins," J. Am. Water Works Assoc. 59: 1257-1267, (1967).
Amirtharajah, A. "Design of Flocculation Systems," Water Treatment
Plant Design, Ed. by R.L. Sanks, (Ann Arbor, Mich.; Ann Arbor
Science Publ., 1979).
Canale, R.P. and J.A. Borchardt. "Sedimentation," Physicochemical
Processes for Water Quality Control, by W.J. Weber, (New
York; Wiley-Intarscience, (1972).
O'Connell, R.T. "Suspended Solids Removal," Water Treatment Plant Design,
Ed. By R.L. Sanks (Ann Arbor, Mich.; Ann Arbor Science Publ.,
1979).
72
-------
14. Conley, W.R. and S.P. Hansen. "Advanced Techniques of Suspended
Solids Removal," Water Treatment Plant Design, Ed. by R.L.
Sanks, (Ann Arbor, Mich,; Ann Arbor Science Publ., 1979).
15. Walker, J.K. "Sedimentation," Water Treatment Plant Design, Ed. by
R.L. Sanks, (Ann Arbor, Mich.; Ann Arbor Science Publ., 1979).
16. Hudson, H.E. Jr. "Density Considerations in Sedimentation," J. Am. Water
Works Assoc. 64: 382-386. (1972).
17. Baumann, E.R. "Granular-Media Deep-Bed Filtration," Water Treatment
Plant Design, Ed. by R.L. Sanks, (Ann Arbor, Mich.; Ann Arbor
Science Publ., 1979).
18. Clark, R. M. and J. M. Morand. "Package Plants: A Cost-Effective
Solution to Small Water System Treatment Needs," J. Am. Water
Works Assoc. 73 : 24-30 (1981).
73
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TECHNICAL REPORT DATA
{Pitas* rtad Instructions art tftt rtvtrst btfort completing) I
1. REPORT NO. 2.
EPA-600/2-82-101
X RECIPIENT'S ACCESSION NO.
4. TITUS ANO SUST1TLS
Performance Characteristics of Package Water
Treatment Plants
S. REPORT OATS
December 1982
S. PERPORMING ORGANIZATION COOS
7, AUTHORIfl
James M. Morand
Matthew J. Young
S. PERFORMING ORGANIZATION REPORT NO.
9. PERPORMING ORGANIZATION NAMI AWQ aqoress
Department of Civil and Environmental Engineering
University of Cincinnati
Cincinnati, Ohio .45221
10. PROGRAM ELEMENT NO.
C-104 BNC1A Task 78
W CSWfHACf/fiAANT NO.
CR-806449
12. SPONSORING AGSNCY NAMf ANO AOQRS5S
Municipal Environmental Research Laboratory-Cin. OH
Office of Research & Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
13. TYPE QP REPORT ANO PERIOD COVERED
Pinal 12/78 - 12/81
14. SPONSORING AGENCY COOS
EPA/600/14
IS. SUPPLEMENTARY NOTES
Project Officer: Thomas J. Sorg (513-684-7370)
18. ABSTRACT
This study was undertaken to collect reliable onsite information on the quality
of treated water produced by package plants. Six plants in operation year around
were selected to be representative of those serving small populations and were moni-
tored to assess their performance* Plants selected used surface water sources*
Sampling trips were made over a 2 year period. At each plant» samples were
collected of the raw water, the treated water, and water from the distribution
system. Turbidity, total coliform, and chlorine residual data were collected on all
visits. Standard plate counts, chemicals listed in the USEPA Drinking Water Regula-
tions, and trihalomethanes were determined intermittently.
Only one treated water samplfe, a distribution sample, showed any total con-
forms. Sixty-eight percent of the treated water standard plate counCs showed
densities of 10 or less per milliliter. Three of the plants met the 1 ntu turbidity
standard on nearly all occasions* The other three plants were meeting the standard
during less than half of the sampling trips. Failure of these plants to perform
well is attributed to the variability and quality of their sources and/or to the
lack of skilled operators having sufficient time to devote to treatment.
17. KtV WOHOS ANO OOCUM«NT ANALYSIS
a. oiscntrrons
b.lOINTtrttflS/OFKN SNOI0 TERMS
c. cosati Field/Group
IE. DISTRIBUTION STATEMENT
Release to Public
19. $iCu*iTv class (THu A*peni
Unclassified
21. NO. 0^ PAGES
84
as. sscuaity class
Unclassified
33. P*lCE
IP* P*m 2220*1 HU«. 4•77) «Oit»oh ts sih;
74
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