FLUORIDE REDUCTION
in
COMMUNITY WATER
/ -Jif
i
'
'
prepared for the •.
STATE OF SOUTH CAROLINA
DEPARTMENT OF HEALTH & ENVIRONMENTAL CONTROL
WATER SUPPLY DIVISION
» JOUT VENTURE
J. E. SI RHINE COMPANY & AWARE, INC.
Summerville, South Carolina Bnntwood, Tennessee
volume TWO
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
AMERICAN HFRITAGE MOBILE HOME PARK
LEXINGTON COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Estimated Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Method . • .. 4
Cost Estimate 5
Implementation 5
Operator Requirements 6
SU ARY 6
REFERENCES 7
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) Ilational
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of erican Heritage Mobile Home Park. In
addition to addressing the conceptual solution from a technical standpoint, plan-
ning-level cost estimates are also presented. It should be noted that all capi-
tal costs are presented in 1980 dollars and that all operating expenses were
calculated at 1979 water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The American Heritage Mobile Home Park water system has two wells. One well is
425 feet deep, yields 45 GPM, and has a fluoride concentration of approximately
3.3 mg/l. The second well is 385 feet deep, yields 28 GPM, and has a fluoride
concentration of approximately 1.9 mg/i. 1 The water system has a 5,000 gallon
pneumatic tank for water storage. The system serves 165 mobile home sites. When
visited during this study, approximately 40% of the trailer sites were occupied.
The system has no water meters with which water use can be determined.
ESTIMATED WATER DEMAND
Assuming two persons per mobile home and a water use of 70 GPD per person, it was
estimated that the average daily water demand would be 23,100 GPD. If it is
2
assumed that the peak day water demand is 180% of the average day water use,
the water demand would be 41,580 GPD.
With that demand, the desirable minimum pumping rate would then be 43.4 GPM,
which would allow the estimated peak day water demand to be pumped in 16 hours.
If Ameen’s method 3 for predicting instantaneous water demand on the supply system
is used, the estimated demand would be 249 GPM. However, this estimate is based
on each residence having four persons who use a total of from 400 to 500 GPD.
4
Since this system serves a trailer park, DHEC has indicated that 80% of Ameen’s
instantaneous demand can be used as the estimated demand. Using this instantane-
ous water supply demand, Ameen’s method 3 of checking pneumatic tank size indicates
that a well capacity of at least 155.8 GPM would be needed with the existing 5,000
gallon of pneumatic water storage. However, an additional 7,500 gallons of pneu-
—2—
-------
water use of 231 GPD per consumer, the future average day water demands were esti-
mated to be 86,625 GPD by 1990 and 98,175 by the year 2000.
Using the peak month record as a guide, it is estimated that the peak day water
use is approximately twice the average day water use. Therefore, the peak day
water demands are estimated to be 173,250 GPD for 1990 and 196,350 GPD for the
year 2000.
The below listed supply requirements were calculated utilizing a regulatory
criterion requiring that the well or wells be capable of meeting the maximum
daily demand in a 16-hour operating period. Those values are as follows:
• 1979 - 132 C,PM;
• 1990 - 180 GPM;
• 2000 - 204 GPFI.
Based on the above estimates, a pumping capacity of 150 GPM was selected as the
capacity for the ensuing evaluations.
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recogniz-
ing that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative should include a reevaluation of capital and operating
costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Method
The alternative would involve the drilling of a new well or wells to replace or
blend with one of the existing high fluoride wells. For the blending alternative,
it will be assumed that an existing well’s pump will be replaced with a smaller
unit to achieve an acceptable blend. It should be noted that this alternative is
dependent upon the quantity and quality of low fluoride water available, both of
which are unknown. Therefore, for this to be a viable solution, a test and water
—4-
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Iater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to t e South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA end prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Central Mobile Home Village. In addition
to addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Central Mobile Home Village water system has two wells in use. One is
340 feet deep and yields 90 GPM and one is 270 feet deep and yields 30 GPM
1
for a total yield of 120 GPM. The system’s fluoride concentration is
approximately 3.5 mg/i. 2 The water system has a 745 gallon pressure tank for
water storage. The system served approximately 70 persons in 36 mobile homes
during 1979. The number of trailers and the population is expected to remain
stable. There are no meters in use and, therefore, water use must be estimated
from use in similar systems.
ESTIMATED WATER DEMAND
Assuming two persons per mobile home and a water use of approximately 100 GPD
per person, it is estimated that the average daily water demand would be approx-
imately 7,200 GPD. If it is assumed that the peak day water demand is 180% of
the average day water use, 3 the water demand would be 12,960 GPO.
With that demand, the desirable minimum pumping rate would be 13.5 GPM, which
would allow the estimated peak day water demand to be pumped in 16 hours. If
4
Ameen’s method for predicting instantaneous water demand on the supply system
is used, the estimated demand would be 36 resd. x 3.56 GPM/resd. = 128 GPM.
• However, this estimate is based on each residence having four persons who use
a total of from 400 to 500 GPD. Since this system serves a trailer park, DHEC
has indicated 5 that 80% of .4meen’s instantaneous demand can be used as the esti-
mated demand. Using this instantaneous water supply demand, Ameen’s method 4 of
-2-
-------
FLUORIDE REDUCTION
IN
COMMUNITY WATER SUPPLIES
Prepared For
STATE OF SOUTH CAROLINA
DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL
WATER SUPPLY DIVISION
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
Summerville, S. C. Brentwood, TN
VOLUME TWO
-------
NOTICE
This volume contains one copy each of forty-three
reports which were bound separately and transmitted
to communities throughout the eastern section of
South Carolina. As an adjunct to the reports, three
Appendices were prepared to address items of common
interest to many of the communities included in the
study. All such appendices have been printed at the
end of this Document, but have been omitted from the
individual reports to avoid redundancy. To determine
which appendices were included in the separately bound
reports, the reader should consult the appropriate
Table of Contents.
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded-the established fluoride standard. SC DREG
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DREC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Aynor. In addition to addres-
sing the conceptual solution from a technical standpoint, planning—level cost
estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Aynor water system presently has two wells in use. 1 Well No. 1, located near
the Town’s 100,000 gallon elevated water tank, is pumped at approximately 1501
gallons per minute (GPM), has a fluoride concentration of approximately 5.0 mill-
igrams per liter (mg/i) and an iron concentration of less than 0.1 mg/i. 2 Well #2,
located near the corner of North Main Street and Sixth Avenue is also reported 1 to
be pumped at approximately 150 GPM. Both wells are constructed to the same depth;
therefore, the chemical quality of water from the two wells is expected to be
approximately the same.
The Town’s water use 3 during the peak month for three past years is tabulated
below.
TOWN OF AYNOR
PEAK MONTH WATER DEMAND
Period
(month/year)
Average Demand
(gal/day)
Consumers
Consumer Average
(gal/day)
9/77
9/78
9/79
132,000
139,000
127,000
310
318
325
426
437
391
The average water use for 1979 was estimated to be 75,000 GPD. 4 The combined
yield of the Town ’s two wells is approximately 288,000 GPD with 16 hours of pump-
i ng.
FUTURE CONDITIONS
The estimates by the Town 3 of the future number of water service customers are 375
customers by the year 1990 and 425 by the year 2000. Using the current average
—2-
-------
checking pressure tank size indicates that a well capacity of at least 93.2 would
be needed if the existing 745 gallon tank is all the storage available. However,
an additional 6,500 gallons of pneumatic tank capacity would allow the use of a
13.5 GPM well, which is estimated to be sufficient to meet the peak day demand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 36 residential connections assumed as design condition.
2. Existing pneumatic tank size is 745 gallons.
3. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Ameen in his book entitled “Cornunity Water Systems” on pages 50
through 55, except that instantaneous demand is reduced to 80% of Anieen’s
estimate.
Calculations:
1. 36 residences x 3.56 GPM/res. x 0.8 = 102.5 GPM instantaneous demand.
2. Usable pneumatic tank volume = 745 4 — 186.25 gallons.
3. Tank contribution for 20 minutes = 186.25 gallons.
4. Minimum new well size to meet instantaneous supply demand = 102.5 GPM -
9.3 GPM = 93.2 6PM.
5. Minimum pneumatic tank capacity with 13.5 6PM well = (102.5 GPM — 13.5 GPM)
x 20 minutes x 4 = 7,120 gallons.
6. Additional pneumatic tank capacity needed = 7,120 gal. - 745 gal. =
6,375 gallons. Use a 6,500 gallon tank.
—3-
-------
FLUORIDE REDUCTION
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the comunity’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
METHOD
The viable alternatives for this system appear to be quite limited. One possible
alternative would be to connect to the City of Conway’s proposed water main ex-
tension out Highway 701 to a proposed industrial site. However, the end of the
water main would be approximately 2.9 miles from the Central Mobile Home Village.
With a construction cost of $4.00 per foot for a 4” diameter PVC pipe installation,
the cost would be over $60,000. Other costs would include design costs, a master
meter installation, drive and roadway repairs, etc. Due to the high cost per
residence, this possible alternative has been eliminated by the writer. Treatment
for fluoride reduction has also been eliminated for the same reason.
The only viable alternative for this system appears to be the drilling of a new
well to tap a more acceptable water source. tIith a fluoride concentration of
-4-
-------
zone sampling well must be drilled near one of the existing wells and sufficient,
satisfactory water located tb replace or blend with the existing well water.
Assuming the test well process locates blend water with a fluoride concentration
of 0.2 mg/l or less, a blended water fluoride concentration of approximately 1.4
mg/i can be achieved by using 38 GPM of existing well water with 112 GPM of low
fluoride water. One problem which could occur in trying to achieve this much
low fluoride water is that the blend water may have a high iron concentration.
In that event, either sequestering of the iron to keep it in solution or iron
removal treatment would be required.
For this alternative, it will be assumed that one test and sampling well, followed
by two production wells, will be needed to achieve the 112 GPM required for blend-
ing with one existing well only. It will also be assumed that an iron sequester-
ing and a gas chlorination unit will be needed at the selected existing well site
and that one new well will be installed near the existing well and one will have
to be piped to the existing well site. To indicate the impact of excessively
high iron content in the new wells, the cost of iron removal treatment has also
been estimated. However, it is beyond the scope of this study to predict whether
or not iron removal treatment would be necessary.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction $90,000
• Annual added debt service assuming 12% loan for 30 years $11,174
• Annual added operation cost using 1979 estimated water use $ 826
• Total estimated added annual cost $12,000
-5-
-------
Cost Estimate with Iron Removal
• Capital cost estimate for project design and construction $230,000
• Annual added debt service assuming 12% loan for 30 years $ 28,555
• Annual added operation cost using 1979 estimated water use $16,125
O Total estimated added annual cost $ 44,680
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendum, rate structure studies,
funding procurement, etc., provided only iron sequestering is required. It is
estimated that the time would increase to 42 months if iron removal treatment is
required.
Operator Regui rernents
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative, if only iron sequestering is required. However,
if iron removal treatment is necessary, it is anticipated that an additional water
systeri operator may be required. Therefore, the expense of an operator has been
added to the estimated operating cost.
ALTERNATIVE NO. 2: TREAT EXISTING WELLS
Method
This solution would involve the treatment of well water from either of the two
existing wells. To provide back-up protection, the cost of piping to al1ow either
existing well to be used is included in the cost estimate. The treatment process
which appears to be the least expensive to reduce the fluoride concentration is
the activated alumina process. This process would involve treatment of a portion
-6-
-------
of the flow from the well being used and the blending of the bypassed portion
with the defluoridated water. When the treatment capacity is exhausted, the
unit must be regenerated and the backwash discharged to the nearest sanitary
sewer system. The Town would have to incur cost to pipe to that sewer and pay
for treating it. For a description of the activated alumina process, see the
Appendix entitled “Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $340,000
• Annual added debt service assuming 12% loan for 30 years $ 42,208
• Annual added operation cost using 1979 estimated water use $ 27,000
• Total estimated added annual cost $ 69,208
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed A operator for those systems em-
ploying activated alumina fluoride removal technology. The present state license
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination,
in order to obtain an “A” operating license. Approximately 120 hours of formal
training should be adequate to upgrade operator skills to the level required by
—7-
-------
the proposed treatment system. The actual cost to the comunity for this train-
ing is anticipated to be approximately $3,000 plus travel and living expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
AYUOR
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequesteri ng)
lb. 2: Treatment
150
150
$11,174
$42,208
$ 826
$27,000
$ 36.92
$212.95
Based upon the above listed information, Alternative 110. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Implementation of that alternative would result in the following water rate
increase:
• Existing monthly rate 3 $ 9.40
• Estimated monthly increase 3.08
Adjusted Monthly Water Rate $12.48/consumer
-8-
-------
REFERENCES
Meeting and discussion with Aynor’s Mayor, Hoyt Johnson, and Water Superintendent,
Benny Andrews, on January 31, 1980.
2 DHEC Water Analysis, from Aynor Well #1, dated April 3, 1980.
3 Written data received from Town personnel following January 31, 1980 meeting.
4 Telephone communication with Ms. Graham on April 24, 1930.
5 DHEC Staff Study on Fluoride for Aynor, South Carolina, dated May 15, 1978.
-9-
-------
FLUORIDE REDUCTION
I N
PUBLIC WATER SUPPLY
OF
BELMO 1T SUBDIVISION
DORCHESTER COUNTY. SflUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Paqe
INTRODUCTION 1
BACKGROUND
Consumers . . . 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirement 2
Existing Supply 2
FLUORIDE REDUCTION
Method 3
Cost 3
Implementation 4
Operator Requirements 4
REFERENCES S
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE TOtIFI OF AYFIOR
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLI 1A DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Future Conditions 2
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method 4
Cost Estimate with Iron Sequestering 5
Cost Estimate with Iron Removal 6
Implementation 6
Operator Requirements 6
Alternative No. 2: Treat Existing Well
Method 6
Cost Estimate 7
Implementation 7
Operator Requirements 7
Summary 8
REFERENCES . . . . . . g
APPENDIX
Fluoride Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking later Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
çr nted to tne South Carolina Department of Health and Environmental Control
(SC DHEC). investigations conducted by the State revealed that approximately
60 pjblic water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providin a conceptual solution to the reduc-
tion of fluoride in the water supply of Belmont Subdivision. In addition to
addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
Belmont Subdivision is an established residential community. It is located
in Dorchester County and lies to the west of the Town of Sumerville. The
water system serving Belmont Subdivision provided water to 32 consumers,
approximately 100 people, as of July, 1978.1
L IATER SUPPLY REQUIREF1ENTS
Current Demand
Accurate data on actual water use in this community is not readily available.
Consequently, system averages developed from records of similar communities
were utilized as a basis for establishing assumed values which will be utilized
in ensuing sections of this report. An average daily usage of 160 gallons per
connection and a maximum daily demand factor of 180% were used to establish
the following system demand data
• Average Daily Demand 5,120 gallons
• Maximum Daily Demand 9,216 gallons
Supply Requirement
The domestic supply requirement for this comunity was assumed to be 6 GPM , the
average flow during a period of maximum demand.
EXISTING SUPPLY
The existing water supply consists of one well of unreported capacity. 1 The
water produced by the well contains 2.9 mg/i fluoride which exceeds the limit
2
of 1.6 mg/i established by law.
-2-
-------
FLUORIDE REDUCTION
METHOD
Based upon available information, the most practical and least expensive
method of effecting a fluoride reduction in this community is to abandon the
existing supply and purchase water from the Town of Summerville. Belmont
Subdivision is located approximately 4,200 feet from the nearest Sucimerville
.iain; therefore, construction of a new 6” line will be required as shown on
Figure ‘Jo. 1. It should be noted that the proposed installation includes four
hydrants spaced at 1,000 foot intervals along Sweatman Road.
COST
Due to the lack of fire hydrants within the subdivision, it was determined that
a 2’ master meter would meet the requirements of this community. The cost
of a 2 connection including the meter has been estimated at Sl,200. 3 It
will be the owner’s responsibility to obtain the necessary pernits, to design
the waterline, and to subsequently install it.
The estimated construction cost of the complete line including 6” pipe, hydrants,
tap, meter, engineering, and project contingency expenses is 35,200. Annual
debt service expense on that amount calculated at 12% for 30 years is $4,369.
The increase in annual expenses attributable to this change was calculated as
follo ,s:
—3-
-------
Figure 1
SCHEMATIC DIAGRAM OF PROPOSED
WATER SUPPLY ADDITIONS
at
BELMONT
S/D
PROPOSED 6” WATER
MAIN WITH FIRE
(4 REO’D.)
TIE TO EXISTING
WATER MAIN
TIE TO DISTRIBUTION
SYSTEM AT EXISTING
WELL W/ 2” METER.
OAKRIDGE
ESTATES S/D
TI
BELMONT SUBDIVISION
-------
• Debt Service $4,369
• Plus Water Purchase 1 ,754
Subtotal $6,123
• Less Power Cost 123
Total Annual Increase $6,000
Presuming that the increase calculated above will be amortized uniformly over
the existing consumer population, the annual incremental increase was calculated
to be $187.50 per consumer ($15.63/month).
IMPLEMENTATION
Design, securing permits and approvals, solicitation of proposals, contract
negotiation and award, and construction of the above-described facilities can
be accomplished within 24 months of completion of required referendums, rate
structure studies, funding procurement, etc.
OPERATOR REQUI REMENTS
Operator requirements for this system will not change as a consequence of
fluoride reduction in the water supply.
-4-
-------
REFERENCES
‘South Carolina Department of Health and Environmental Control, “Staff Study
for Belmont Subdivision, Dorchester County, April 25, 1978.”
2 $outh Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Sample No. R06208-1602, June 29, 1978.
3 Personal communication, Mr. Roy Winey, Town of Sumnerville, March 27, 1980.
-5-
-------
FLUORIDE REDUCTION
I N
PUBLIC WATER SUPPLY
OF
BRIARCLIFFE SUBDIVISION
HORRY COUUTY, SOUTH CAROLIIIA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Method
Cost Estimate
Implementation
Operator Requirements
Alternative No. 2: Purchase
Method
Cost Estimate
Implementation
Operator Requirements
Alternative No. 3: Fluoride
Method
Cost Estimate
Implementation .
Operator
Summary
REFERENCES
APP Eli DIX
Fluoride Treatnent
Page
1
2
2
3
5
3
5
5
6
6
6
7
7
7
7
8
9
INTRODUCTION
BACKGROUND
Existing Conditions
Future Conditions
FLUORIDE REDUCTION
Alternative No. 1: Drill Well(s)
Beach
for Blending
‘later
frori 4 yrtle
Renoval Treatnent
Requ i rements
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
crar ted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public .iater supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Briarcliffe Subdivision. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Briarcliffe Subdivision water system has two wells in use and a third well
which is not used because it has a high iron concentration. 1 The system has a
2
50,000 gallon elevated tank which is used for water storage. Data on record
with DHEC or from the Owner on the existing wells is tabulated below.
BRIARCLIFFE SUBDIVISION
EXISTING WELL DATA
Well
.
Capacity
(Gal/Ilin)
.4
Fluoride
(mg/i)
4
Iron
(mg/i)
#1 (Deep)
#2 (Shallow)
#3 (Shallow)
300
70
60
5.0
0.1
0.20
0.7
FUTURE CONDITIONS
The Briarcliffe Subdivision has a planned ultimate development lot and multifamily
unit layout which would have a total of approximately 773 residential units. 3
Using their current average water use of 289 GPD per dwelling, their future average
water use would be 0.223 MGD. Using their current estimated peak day factor, their
future peak day would be approximately 0.37 MGD. It should be noted that the 300
GPM well alone could meet this estimated demand in approximately 20.6 hours of
pumping. Therefore, for the purposes of this report, the alternatives to solve
the fluoride reduction problem will be sized to provide at least 300 GPM of accept-
able water.
-2-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for this comunity. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Finan ial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELL(S) FOR BLENDING
Method
The alternative would involve the drilling of an additional shallow well or wells
to blend with the existing high fluoride well. This alternative is heavily depen-
dent upon the quantity and quality of low fluoride ground water available, which,
lacking other data, will be assumed to be similar to the existing shallow well
presently in use. Using the fluoride concentration of the two wells presently
-3-
-------
used, it has been calculated that a blended water fluoride concentration of 1.4
mg/i can be achieved by blending 80 GPM of the high fluoride water with 220 GPM
of the low fluoride, shallow well water. The 1.4 mg/l blend concentration was
selected to cover variations which occur in fluoride concentrations and well pump-
ing rates. This yield and blend could possibly be achieved by adding an addi-
tional shallow well or wells, tying these to the three existing wells and
replacing the existing deep well pump with an 80 GPM unit.
One known problem with blending at the above-described rate is that the blend
water iron concentration is estimated to be 0.57 mg/i which is well above the
accepted aesthetic limit of 0.3 mg/i. However, since this limit is a Secondary
Standard with DHEC, the high iron concentration can be accepted, provided it can
be kept in sciution, by sequestering and the users accept this water without com-
plaint. Also, it is inportant that the water from the two wells be tested at the
prescribed blend to see if any other problems occur.
It should be mentioned that, although it does not appear that iron removal treat-
ment will be required, this possibility does exist.
The components of the basic well blending solution are (1) the installation of
two additional shallow wells on properly spaced new well sites, (2) the piping
of these wells to the main deep well and the blending of new wells with the
three existing wells, (3) the installation of an iron sequestering unit with a
small enclosure building, and (4) the replacement of the deep well pumps with an
80 GPM pump.
-4-
-------
Cost Estimate
• Capital cost estimate for project design and construction $llO,0”)O
• Annual added debt service assuming 12% loan for 30 years $13,657
• Annual added operation cost using 1979 water use $ 1,200
• Total estimated added annual cost $ 14,857
Implementation
It has been estimated that design, securing of oer’iiits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the conpietion of rate structure studies, required referendum,
funding procurement, etc., provided only iron sequestering is required. It is
estimated that the time would increase to 42 months if iron rer ova1 treatment is
required.
Qperator Requi rements
Operator reauirements for this system are not expected to change as a consequence
of implenenting this alternative, if only iron sequestering is required. However,
if iron removal treatment is necessary, it is anticipated that an additional
water system operator may be required.
ALTERNATIVE NO. 2: PURCHASE WATER FRO 1 MYRTLE BEACH
Met hod
The alternative would involve the installation of approximately 3,500 feet of not
less than 6 inch diameter water main and a master meter assembly and vault. 5
Myrtle Beach has indicated that a 12 inch water main would be the small-
est size that they would like to have installed. The details of exactly what size
water main and how it would be paid for would obviously have to be worked out with
Ilyrtle Beach.
-5-
-------
For this report, costs will be estimated on the basis of a 6 inch water main and
meter installation. The 6 inch meter installation fee was estimated 5 to be $9,000
plus a $625 deposit for an out-of-town customer and $4,500 plus a $325 deposit
for an in-town customer. The actual water use costs would be $1.14 per 1,000
gallons for an out-of-town customer and $0.57 per 1,000 gallons for an in-town
customer. Since Briarcliffe could be annexed into the City of rlyrtle Beach to
save costs, it will be assumed for this report that the in-town fees will be in
effect. Also, since Myrtle Beach will need to increase their rates to cover the
cost of reducing the fluoride in their system, the water rate increase due to
their least expensive alternative must be added to their current $0.57 per 1,000
gallon rate. This would add approximately $1.07 per 1,000 gallons to the cost of
the water.
Cost Estimate
• Capital cost estimate for project design and construction $35,000
• Annual added debt service assuming 12% loan for 30 years $ 4,345
• Annual added water cost, less power cost, using 1979 water use $70,261
• Total estimated added annual cost $74,606
Implementation
It has been estimated that securing an agreement, design, securing of permits and
approvals, advertisement, contract execution, and construction of this alternative
can be accomplished within 24 months of the completion of rate structure studies,
required referendum, funding procurenent, etc.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
-6-
-------
ALTERNATIVE NO. 3: FLUORIDE REMOVAL TREATMENT
Method
This solution would involve the treatment of the 300 GPM flow from Well #1. The
treatment process which appears to be the least expensive to reduce the fluoride
concentration is the activated alumina process. This process would involve
treatment of a portion of the flow from each well and the blending of the bypassed
portion with the defluoridated water. When the treatment capacity is exhausted,
the unit must be regenerated and the backwash discharged to the sanitary sewer sys-
tem. For a description of the activated alumina process, see the Appendix entitled
“Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $397,000
• Annual added debt service assuming 12% loan for 30 years $ 49,284
• Annual added operation cost using 1979 water use $ 38,500
• Total estimated added annual cost $ 87,784
Impi ernentati on
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state ii—
—7—
-------
cense system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120
hours of formal training should be adequate to upgrade operator skills to the
level required by the proposed treatment system. The actual cost to the commun-
ity for this training is anticipated to be approximately $3,000 plus travel and
living expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
BRIARCLIFFE SUBDIVISION
ALTERflATIVE SUMMARY
Alternative
Capacity
(GPrI)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Purchase
No. 3: Treatment
300
N/A
300
$13,657
$ 4,345
$49,284
$1,200
$70,261
$38,500
$ 35.63
$178.91
$210.51
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate $20.05
• Estimated monthly increase 2.97
Adjusted Monthly Water Rate $23.02/consumer
-8-
-------
REFERENCES
1 Meeting and discussion with flr. Sing, Briarcliffe water system operator for
Carolina Water Services, Inc., Owner, on January 24, 1980.
Staff Study on Fluoride for Briarcliffe Subdivision, dated May 15, 1978.
3 Telephone communication with Mr. Sing, on May 1, 1980.
4 lelephone communication with Mr. Fred Soland of DHEC on May 2, 1980.
5 Telephone communication with Mr. Bill Bull, Superintendent of Water & Sewer
Department for Myrtle Beach, South Carolina, on April 21, 1980.
-9-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
BUCKSPORT WATER COMPANY
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
INTRODUCTION
BACKGROUND
Consumers
WATER SUPPLY REQUIREMENTS
Current Demand
Supply Requirement
Existing Supply
FLUORIDE REDUCTION
Alternative tIc. 1: Blending
Alternative No. 2: Purchase
Alternative No. 3: Regional System
Alternative No. 4: Treatment
Alternative No. 5: Pee Dee River
SUMMARY
REFERENCES
APPEND I CES
Regional Water System
Page
1
2
2
2
2
4
7
9
10
11
12
14
-------
I NTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Jater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forceirent responsibility for the standards as requested by and subsequently
to the Sc th Car 1ina Department of aith and Environmental Control
•: DAEC). I vestigaticns conducted by the State revealed that approximately
2 bi ic ater suppi i25 ecceded the established fluoride standard. SC DHEC
pE onnei have .orkad w th the affected communities in a concerted effort to
cieveiOD rational solutions to the problem. This report, which was funded by
EPb and ,repared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
in 19& , a stud ’ of each community water supply which exceeded the
1e a1 1 ‘it for :luor.ide was initiated. The established objective of that in-
\2stig : .e e”ort as to ident’fy one or more viable fluoride reduction alter-
natives for- each comriunity. This report documents that portion of the study
which t:as directed specifically at providing a conceptual solution to the reduc-
tion of f’uoride in the t ater supply of Bucksport Water Company. In addition to
addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
CON SUMERS
The Bucksport Water Company provided service to 303 consumers, approximately
1
1 ,060 people, as of February, 1978.
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this community is not readily available. Con-
sequently, system averages developed from records of similar cornunities were uti-
lized as a basis for establishing assumed values which will be utilized in ensuing
sections of this report. An average daily usage of 200 gallons per connection and
a maximum daily demand factor of 180% were used to establish the following system
demand data:
• Average Daily Demand 60,600 Gallons
• Maximum Daily Demand 109,080 Gallons
Supply Requirement
Utilizing an assumed criterion requiring that the well or wells be capable of meet-
ing the maximum daily demand in a 16-hour operating period, the present supply
requirement was calculated to be 113 GPM.
Existing Supply
The existing supply consists of two deep well installations. One is located along
U.S. Highway 701 and consists of one 175 GPM well and one 10,000 gallon pneumatic
storage tank. The other is located along S. C. Route 237 and consists of one 90
-2-
-------
GPM well and one 5,000 gallon pneumatic storage tank. 2 Water supplied by the
existing wells contain 2.6 mg/i fluoride and 3.0 mg/l fluoride respectiveiy. 2
-3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified five viable fluoride reduction alter-
natives for the Bucksport Water Company. Each alternative was subsequently evalu-
ated to determine the most practical and least expensive method of effecting a
solution to the fluoride problem. The ensuing paragraphs of this report document
the results of the evaluations and rank the alternatives in their order of desira-
b iii ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
It should be noted that the scope of this study was limited and therefore assumed
that the existing distribution system has sufficient hydraulic capacity to accomo-
date changes in the location and/or input in the point of supply.
ALTERNATIVE NO. 1: BLENDING
Method
Fluoride reduction can be achieved by drilling a series of shallow wells and blend-
-4-
-------
ing their yield with that of the existing deep wells. Assuming a fluoride concen-
tration of 0.1 rng/l in the proposed shallow wells, a shallow/deep mix of 1.00 GPM/
0.92 GPM will result in a blend having a fluoride concentration of 1.4 mg/l.
This alternative addresses construction of shallow blending wells at Well #1
(175 GPM). Well #2 (90 C-PM) was not considered because increased capacity (shal-
low plus deep) of Well #1 will exceed the existing capacity of both deep wells.
Utilizing a blend ratio of 1 shallow/0.92 deep, the required shallow well capac-
ity was deteniiined to be 161 GPM. Lacking accurate data on the quantity of shal-
low ground water available in the Bucksport area, yield was conservatively
estimated at 60 GPrI per well, requiring construction of three wells.
The capacity of the system as proposed herein should accomodate a consumer popu-
lation of 600 residential connections, 2,100 people. That capacity as verified
as follows:
• Well capacity based uoon a 16-hour operating period
Required
(6Y)ta .ps)(200GPD)(1.8) = 225 GPM
(16 hr)(60 min/hr) —-____
Available
175 GPII + 180 GPM = 355 GPM
• Pneumatic storage capacity required. 3
Total Instantaneous Demand
*(08 GPM)(600 homes) = 480 6PM
Instantaneous Supply Demand
(480 GPf1)(20 mm) = 9,600 CPu
Available Pumping Capacity
(355)(20 mm) = 7,100 Gallons
*The instantaneous demand for a system with 600 homes connected to it is 0.8 GPM/
connection.
—5—
-------
x
x
SHALLOW
3 REQ’D.
-r
I—
I Ot— -
L__J
PROPOSED EQUIPMENT
BUILDING
D(ISTING 175 GPM
DEEP WELL
-—-----101
L._J
- -
I I
V//i//A I
/I
-, -I-
FIGURE 1
PROPOSED
3 ACRE
WELL FIELD
‘C.
TO___
SYSTEM
SCHEMATIC DIAGRAM OF
PROPOSED WATER SUPPLY ADDITIONS
AT
I0I—
L6OGPM
I WELL,
J
L__J
EXISTING 10,000 GAL
PNEUMATIC TANK
BUCKSPORT WATER COMPAfIY
-------
Pneumatic Storage Requirement
9,600 gal — 7,100 gal
**0.25 = 10,000 Gallons
Sufficient iron to cause aesthetic problems, such as staining of plumbing f ix-
tures, should be expected in the proposed shallow wells. With the favorable
ratio of deep/shallow well water that will be utilized in this system, it was
assumed that the iron could be sequestered and then diluted sufficiently to pre-
clude the occurrence of iron related nuisance problems. Feeding a solution of
polyphosphates (chemical) to the shallow wells will provide an economical means
of controlling red water. The chemical is purchased dry in 50 or 100 pound bags
and mixed with water to form a solution. The mixture is then injected into the
system by a small pump.
A schematic diagram of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recommended is as follows:
• Three 60 GPM shallow wells. Each well should be equipped with a vertical
turbine pump set up to operate simultaneously with the deep well pump.
• One concrete valve pit constructed at the intersection of the deep and
shallow well lines. The pit should contain meters and valves on both sup-
ply lines. The chlorine injection point should be in the tee or the line
leaving the pit.
• Polyphosphate mixing and feed facilities. The concept presented herein uti-
lizes a single chemical feed point in the common main leading from the
shallow wells. However, it should be noted that iron must be in a soluble
form for sequestering to be effective, and that pumping and/or conveyance
may cause the iron to precipitate. Should that situation occur, the chemi-
cal feed point may have to be moved or iron treatment may become necessary.
**pneumatjc tanks ideally satisfy a given water storage requirement by utilizing
25 of the available tank volume for water storage and 75% for air storage.
-6-
-------
Cost
The construction cost of Alternative No. 1 including engineering and project
contingency expenses has been estimated at $180,000. Annual costs are sunuiia-
rized below.
• Debt Service on a 30-Year Loan at 12% $22,345
• Operations and Maintenance 500
Total Estimated Annual Cost $22,845
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requi rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
ALTERNATIVE NO. 2: PURCHASE
Method
This alternative addresses abandonment of the existing deep well supply and replac-
ing same with water purchased fron the City of Conway. The connection would be
effected by constructing a short section of main in the right-of-way of U.S. High-
way 707 and installing a master meter.
Cost
The estimated construction cost of Alternative No. 1 including engineering and
project contingency expenses has been estimated at $100,000. Annual costs are
summarized below.
—7-
-------
• Debt Service on a 30-Year Loan at 12% $12,414
• tIater Purchase 29,151
Subtotal $41,565
• Less Power Cost 2,565
Total Estimated Annual Cost Increase $39 000
The water purchase expense listed above was calculated at a minimum rate of
$5.00/month/consumer for the first 2000 gallons and $0.75 for each additional
1000 gallons, 4 the prevailing service charge rendered by the City of Conway.
It should be noted that City was included in this study and it, too, will
incur additional expenses as a result of reducing the fluoride concentration of
the water supply. Assuming a uniform amortization of the cost associated with
the least expensive alternative developed for Conway, water rates would increase
by $0.64 per 1000 gallons. Utilizing the higher rate, Bucksport’s water purchase
expense was recalculated to be S43,307, bringing the total estimated annual cost
increase for Alternative No. 2 to $53,156.
Implementation
The implementation of this alternative is solely dependent on the availability of
water frori the City of Conway. Assuming imediate availability, this alternative
could be implemented 24 months after completion of required referendums, rate
structure studies, funding procurement, contract negotiations, etc.
Operator Requi rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
-8-
-------
ALTERNATIVE NO. 3: REGIONAL SYSTEFI
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River at Bucksport. Distribution mains convey the water
in a westerly direction as far as Conway, in a southerly direction as far as
Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
See the Appendix entitled “Regional Uater System” for more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional sys-
ten will be S2.95 per 1000 gallons. At the current average daily demand of
60,600 gallons, Bucksport’s annual cost will be S62,251.
Impi emen tat ion
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 60 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
-9-
-------
ALTERNATIVE NO. 4: TREATMENT
Method
This alternative addresses treatment of a portion of the flow from the exist-
ing 175 GPM well utilizing activated alumina. The system would be sized to
treat 110 GPM, the remaining 65 GPM would bypass treatment and be blended with
the defluoridated water. A liquid waste stream from the unit would be discharged
to a wastewater equalization tank. Periodically, the contents of said tank
would be trucked to the Pee Dee River for disposal. Due to the limited amount
of water storage capacity available on this system, a regeneration tank and pump
were included in the cost estimate.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Co s t
The construction cost of Alternative ia. 3 including engineering and project con-
tingency expenses has been estimated at $470,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $58,346
• Operations and Maintenance 46,654
Total Estimated Annual Cost Increase $105,000
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 36 months of completion of required referendums, rate structure studies,
funding procurement, etc.
-10-
-------
Operator Regui rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an A operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level re-
quired by the proposed treatment system. The actual cost to the community for
this training is anticipated to beapproxinately $3,000 plus travel and living
expenses.
ALTERNATIVE 10. 5: PEE DEE RIVER
Met hod
This alternative addresses the construction of an 0.25 MGD package water treat-
ment plant which would process water drawn from the Pee Dee River. The proposed
capacity (175 GPrI) was selected for comparison purposes with the other alterna-
tives. In actuality, a more complete assessment of future water demand might
dictate design and construction of a facility of different capacity.
Cost
The construction cost of Alternative No. 5 including engineering and project con-
tingency expenses has been estimated t $500,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $62,070
• Operations and iaintenance 80,430
Subtotal $142,509
• Less Power Cost (abandoned wells) — 2,500
Total Estimated Annual Cost $140,000
—11—
-------
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 48 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Construction of the treatment facility described in this alternative will require
that a minimum of two water plant operators be added to the existing staff.
Under present regulations, one class “C” operator living within one hours travel
time of the plant and one class “Do operator will be required.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
BUCKSPORT WATER COt4PAEIY
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Purchase
Uo. 3: Regional
No. 4: Treatment
No. 5: Pee Dee
355
N/A
150
175
175
$22,345
$12,414
$56,226
$58,346
$62,070
$ 500
$40,742
$ 6,025
$46,654
$77,930
$ 75.39
$ 175.43
$ 205.00
$ 346.53
$ 462.05
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
—12-
-------
Construction of the primary alternative will result in the following water rate
increase.
• Existing monthly rate 1 $15.70
• Estimated monthly increase 6.13
Adjusted Monthly Water Rate $21.83/consumer
-13-
-------
REFERENCES
‘South Carolina Department of Health and Environmental Control, “Staff Study for
Bucksport Water Company, Harry County, undated.”
2 South Carolina Department of Health and Environmental Control, Water Analyses
Reports on Laboratory Samples numbered P 1782 and p 1783, April 3, 1980.
3 Joseph S. Ameen, “Community Water Systems”, Technical Proceedings, High Point,
North Carolina, 1971.
4 Personal communication, Mr. Winfield, City of Conway, April 14, 1980.
-14-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
BULLS BAY RURAL COMMUNITY WATER DISTRICT
CHARLESTON COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGRO UND
Consumers 2
Water Supply Requirements
CurrentDemand 3
Projected Demand 3
Current and Projected Supply Requirements 4
Existing Supply 4
Proposed Facilities 5
FLUORIDE REDUCTION
Method 6
Cost 7
Uithout Iron Removal S
With Iron Removal 9
Water Rates 9
Operator Requirements
Without Iron Removal 9
With Iron Removal 9
Implementation
REFERENCES 10
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Hea’th and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
63 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In january, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Bulls Bay Rural Community Water District.
In addition to addressing the conceptual solution from a technical standpoint,
planning-level cost estimates are also presented. It should be noted that all
capital costs are presented in 1980 dollars and that all operating expenses were
calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
The Bulls Bay Rural Community Water District provided service to 856 consumers,
approximately 3,167 people, as of January, 1980.1
Population projections for the unincorporated areas of Charleston County lying
east of the Cooper River were obtained from the Berkeley Charleston Dorchester
Council of Governments. Those projections were utilized to develop consumer
projections for the district. It was deemed unrealistic to convert the entire
unincorporated area population directly to consumers because the district does
not serve the entire area. It was however, reasoned that the growth percent-
ages could be applied to the existing consumer population to develop projected
system growth. The computations that were made are summarized in the follow-
ing table.
BULLS BAY RURAL COMMUNITY WATER DISTRICT
CONSUMER POPULATION PROJECTIONS
Year
Population*
Projection
% CHANGE
Consumers
1980
1985
1990
1995
14,942
18,477
21,226
23,866
—0-
23.7
14.9
12.4
856
1,059
1,217
1,368
* Population projection for the entire unincorporated area of Charleston County
lying east of the Cooper River.
-2-
-------
WATER SUPPLY REQUIREMENTS
Current Demand
Daily water demand in the service area currently averages 100,000 GPD. 1
That translates to an average of 117 GPD/connection. Maximum daily demand
was considered to be approximately 180% of average daily usage. 2 Accordingly,
the current water demand placed on the system has been established as follows:
• Average Daily Demand lOO,00 0Ga llons
• liaximum Daily Demand 180,000 Gallons
Projected Demand
The 117 GPD/connection which was utilized in the computation of current demand
is unusually low as compared to usage recorded in similar communities. Two
factors that conceivably influence the low usage are higher than average water
rates and the fact that the system is relatively new. Most horn s that are
connected to the system obtained water from private wells prior to a public
supply being made available to them. Those wells are probably utilized by
consumers for non—potable uses such as car washing and lawn watering in an
effort to minimize their monthly bills. This practice will presumably be
continued by homeowners that presently own a private well. It is however,
unlikely that owners of new homes will invest in private wells as a means of
avoiding a monthly overage charge of a few dollars. Consequently, per connec-
tion water demand can be expected to increase as the system grows. For the
purpose of projecting future demand, 160 GPD/connection was assumed as a
system average. Those projections have been summarized in the following table.
-3-
-------
BULLS BAY RURAL COMMUNITY WATER DISTRICT
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
1995
100,000
170,000
195,000
219,000
180,000
306,000
351,000
394,000
Current and Projected Supply Requirements
The below listed supply requirenents were calculated utilizing
criterion requiring that the well or wells be capable of meeting the maximum
daily demand in a 16-hour operating period. Those values are as follows:
• 1980 - 186 GPM
• 1985 — 319 6PM
• 1990 — 366 GP 1
• 1995 - 410 GPM
EXISTING SUPPLY
The existing water supply consists of one deep well having a rated capacity
of 500 6PM and eight shallow wells having a combined capacity of 200 GPM. Two
of the shallow wells have been abandoned due to the presence of objectionable
concentrations of tannic acid. The remaining six are operational and produce
approximately 150 GPM. The water produced by the deep well contains 5.0 mg/l
fluoride which exceeds the limit of 1.6 mg/i established by law.
The shallow wells were constructed to serve as a source of blending water for
the deep well. Blending being the method chosen to reduce the fluoride
-4—
-------
concentration in the tiater supply to the legal limit or less. To date, the
blending process has been ineffective. Operation of the deep well at
500 GPM would require production of approximately 1 ,250 GPM of fluoride-free
water to effect an acceptable mix.
The shallow wells pump into a common six-inch main which terminates through
a metered connection to the inlet of an existing 25,000 gallon ground level mix-
ing tank. The deeo well is also metered and connected to the inlet side of the
mixing tank. Chlorine is injected in the tank inlet thereby disinfecting the
combined flow.
PROPOSED FACILITIES
The district has obtained permission from the County of Charleston to construct
eight additional shallow wells on county property. 1 The site is presently
fenced and is located approximately 0.3 of a mile from the existing field of
shallow wells.
-5—
-------
FLUORIDE REDUCTION
METHOD
Blending deep and shallow well water in the proper proportions will reduce the
fluoride concentration in the district’s supply to acceptable levels. Maintain-
ing a shallow to deep blend ratio of 2.5/1 will yield a product having a fluo-
ride concentration of 1.4 mg/i.
The success of blending is dependent upon control of the flow from the deep well.
At the 2.5/1 ratio given above, the deep well flow with the six existing shallow
wells should be 60 GPM. After the eight new wells are constructed, the deep well
flow should be increased to 140 GPM. Deep well flows ranging from 50 GPM to 150
GPM are not practically obtainable by throttling the existing 500 GPM vertical
turbine pump. Accordingly, we hereby recommend that a new horizontal booster
pump be installed in the existing building that houses the deep well. (See
Figure 1). Artesian pressure of the existing deep well appears to be sufficient to
accommodate the operation of the booster pump without difficulty. However, the resid-
ual artesian pressure of the deep well should be checked at pumping rates of
50, 100, 150, 200 and 250 GPM prior to initiating the actual design of the booster
pump installation . The proposed pump discharge should be fitted with a globe
valve to facilitate adjustment of the flow rate between 40 GPM and 150 GPM. Exist-
ing meters in both deep and shallow well discharge lines should be used to monitor
the flow rates. Pump controls should remain essentially unchanged providing for
simultaneous operation of the proposed booster pump with the shallow wells.
Recognizing that the above-described blending process dictates a shift from deep
well water to a blend of predominantly shallow well water, the nuisance problems
-6-
-------
PROPOSED
VALVE
Figure 1
SCHEMATIC DIAGRAM OF PROPOSED
BOOSTER PUMP INSTALLATION
at
EXISTING DEEP
WELL PUMP
PROPOSED CHECK
VALVE
PROPOSED
BOOSTER
HORIZONTAL
PUMP
BULLS BAY RURAL COMMUNITY WATER DISTRICT
-------
associated with iron in the water supply must be considered. The existing shallow
wells contain 0.4 PPM iron. 3 At that concentration, iron in its soluble form
(water clear, no red coloring apparent) can usually be stabilized or sequestered
by adding polyphosphates. Where feasible, sequestering is relatively simple and
inexpensive. Unfortunately, the physical arrangement of this system create
some difficulty in locating a suitable feed point for the chemical. Stabilization
of the iron requires that it be in a soluble form. Pumping and/or conveyance to
the deep well site cause the iron to precipitate (turn the water red).
It was beyond the scope of this report to determine whether or not sequestering
is practical; accordingly, the cost estimates assume the t io following extremes:
• The addition of polyphosphates at the deep well site will satisfactorily
sequester the iron contained in the shallow well water, and
• Filtration equipment will be installed at the deep well site for the pur-
pose of iron removal from the shallow well water.
COST
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the facilities were constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the estimated annual cost increase
is placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recornended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
—7—
-------
Immediate compliance can be achieved by installing the proposed booster pump
and utilizing the six existing shallow wells. The installed cost of said pump
and a polyphosphate feed system would be approximately $14,000; however, the
system capacity would be nearly equal to the existing demand and is therefore,
desirable but will only serve as a ‘ 1 ST0P-GAP measure. Full compliance will re-
quire the construction of the eight new wells plus the booster pump. Capacities
achievable with both existing and proposed shallow wells were calculated as
follows:
• Existing Shallow Wells
(6 wells)(25 6PM Ea.) = 150 6PM
Booster Pump = 60 GPM
System Pumping Rate = 210 6PM
(210 GPM)(60 min/hr)(16 hr) = 201,600 GPD
Note: 1980 Demand 180,000 GPO
• Existing and Proposed Shallow Wells
(14 wells)(25 GPM Ea.) = 350 GPM
Booster Pump = 140 GPM
490 GPM
(490 GPM)(60 min/hr)(16 hr) = 470,400 GPO
Note: 1995 Demand 394,000 GPO
Without Iron Removal
The estimated construction cost of the new wells, proposed booster pump, and
polyphosphate feed equipment including engineering and project contingency is
$290,000. Annual costs are summarized below.
• Debt Service on a 30-Year Loan at 12% $36,000
• Operations and Maintenance (polyphosphates) 250
Total Estimated Annual Cost Increase $36,250
• Cost increase per consumer $ 42.35
-8-
-------
With Iron Removal
The estimated construction cost of the new wells, proposed booster pump, iron
removal filters, including engineering and project contingency expenses is
$580,000. Annual costs are summarized below.
• Debt Service on a 30-Year Loan at 12% $72,001
• Operations and Maintenance 17,999
Total Estimated Annual Cost Increase $90,000
• Cost Increase Per Consumer $105.14
Water Rates
As of May, 1978, the average monthly water bill rendered for service from this
system was $28.2O. Assuming that the increased annual cost will be amortized
uniformly, the average water bill will increase to the following:
• Without iron removal $31.73
• With iron removal $36.96
OPERATOR REQUIREMENTS
Without Iron Removal
Operator requirements will not change as a consequence of fluoride removal.
With Iron Removal
The additional level of effort required to operate and maintain the filters will
create one additional staff position for a water system operator.
IMPLEMENTATION
Design and construction of the wells and booster pump can be accomplished within
24 months of the completion of required referendums, rate structure studies,
funding procurement, etc. Should the filters be necessary, eighteen additional
months should be added for a project total of 42 months.
-9-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
CENTRAL MOBILE HOME VILLAGE
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions . 2
Estimated Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 6
SUIIf4AR’( 6
REFERENCES 7
-------
REFERENCES
1 Personal Comunication, John Jacques, Bulls Bay Coninunity Water District,
January, 1980.
2 Clark, J. W., et al. Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
3 Parker Laboratory, Inc., Analysis Report Humber 19871, dated September 20, 1976.
4 South Carolina Department of Health and Environmental Control, “Staff Study for
Bulls Bay Rural Comunity District”, May 1, 1978.
-10-
-------
Discussions with United States Geological Survey personnel and representatives
of South Carolina Water Resources Commission indicate that subsurface conditions
conducive to producing a low fluoride water source improve as the distance from
the ocean increases. Consequently, this alternative addresses construction of
low-fluoride blending wells in close proximity to the Jamestown Well (#5) and
the Caropines Well (#7). The remaining existing wells would be abandoned.
The WRC representative predicted that an average yield of 60 GPM should be pos-
sible per shallow well. Therefore, multiple shallow wells and well lots with
connecting piping will be required to serve the two existing wells. Also, assum-
ing a shallow well fluoride concentration of approximately 0.2 mg/i, the pumping
rate of the two existing wells would be reduced to achieve an acceptable blend
while maintaining a total yield of 1580 GPM.
The following table lists the amount of existing and low fluoride blend water
required for an acceptable fluoride blend and the maximum blend water iron con—
ceritration to achieve a 1.0 mgfl iron blend. The 1.0 mg/i iron concentration is
somewhat arbitrary. Additionally, the critical factor for this alternative is
that the iron in the blended water must be less than 0.3 mg/i, which appears
unlikely, or be suitable for sequestering to achieve an acceptable supply. To
allow a safety factor, a 1.4 mg/i fluoride concentration has been used as the
acceptable concentration in the blended water.
GARDEN CITY BEACH
BLENDING REQUIREMENTS
Existina Wells
Proposed Uells
Well
Fluoride
(mg/I)
Iron
(mg/i)
Reduced
Capacity
Capacity
Iron
(mg/i)
#5
#7
3.2
4.0
0.07
1.30
280 GPM
280 GPM
420 GPH
600 6PM
1.62
086
-5-
-------
Iron sequestering units were assumed to be necessary at each main well site.
To indicate the impact of excessively high iron content in the new wells, the
cost of iron removal treatment has also been estimated and was included in the
cost section as a separate project estimate. It was beyond the scope of this
study to determine whether iron sequestering or removal treatment will be re-
qul red.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$1 ,000,000
$ 124,150
$ 4,000
$ 128,150
Cost Estimate with Iron Removal
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$2,000,000
$ 248,300
$ 20,000
$ 268,300
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 30 months of the completion of required referendums, rate structure studies,
funding procurement, etc. If iron removal becomes necessary, implementation time
will increase to 54 months.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative, if iron sequestering is required. However, if iron removal
-6-
-------
REFER ENCES
‘Meeting and discussion with Mr. Sing, water system operator for Carolina Water
Services, Inc., Owner, on January 24, 1980.
2 Letter to DHEC’s Fred Soland from Carolina Water Service, Inc. dated October 9,
1979.
3 fleeting and discussion with Mr. Allen Zack of the U.S. Geological Survey (USGS)
on February 5, 1980 and Mr. Larry West of the S.C. Water Resources Comission
(WRC) by phone on April 8, 1980.
4 DHEC Staff Study on Fluoride for Garden City, dated May 8, 1978.
—11—
-------
FLUORIDE REDUCTION
I N
PUBLIC WATER SUPPLY
OF
PAWLEY’S ISLAND/”IWiRELL’S INLET COMBINED WATER SYSTEM
GEORGETOWN COUNTY WATER AND SEWER AUTHORITY
GEORGETOWN COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
INTRODUCTION
BACKGROUND
Existing Conditions
Future Conditions
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method
Cost Estimate
Implementation
Operator Requirements
Alternative No. 2: Fluoride Removal Treatment
Method
Cost Estimate
Implementation
Operator Requireiients
Alternative No. 3: Regional Water System
Method
Cost
Implementation
Operator Requirements
Suniuary
REFERENCES . 11
APPENDI CES
Regional Water System
Fluoride Treatment
Page
1
2
3
4
6
6
6
7
7
7
a
8
8
9
9
9
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) F4ational
Interim Primary Drinking Jater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Pawley’s Island/Murrell’s Inlet Combined
Water System. In addition to addressing the conceptual solution from a technical
standpoint, planning-level cost estimates are also presented. It should be noted
that all capital costs are presented in 1980 dollars and that all operating ex-
penses were calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
Georgetown County Water and Sewer Authority (GCWSA) is planning to connect their
Pawley’s Island-Litchfield Beach water system with their Murrell’s Inlet water
system within the next couple of years. 1 This report will evaluate both commun-
ities as one system, the Pawley’s Island/Murrell’s Inlet Combined System.
Data relative to the existing in-service wells was obtained from SC DHEC. That
information is tabulated below.
PAWLEY’S ISLAND/MURRELL’S INLET
EXISTING WELL DATA
Well
1
Capacity
(Gal/Mm)
2
Fluoride
(mg/i)
2
Iron
(mg/i)
#1 S. Pawley’s
#2 N. Pawley’s
#3 S. Litchfieid
#4 N. Litchfield
#6 Mid Litchfield
#11 Murrell’s Inlet
#12 Hagley
#13 Litch. Plant.
Not in Use
225
250
225
275
235
100
500
3.8
4.2
4.7
5.7
4.4
4.0
1.1
3.0
0.40
0.10
0.10
0.10
0.10
0.04
0.01
0.01
As indicated above, only 11e11 #12 is known to have an acceptable fluoride con-
centrati on.
From data provided by GCWSA, the combined system served an average of approxi-
mately 2,555 residential equivalent customer connections in 1979, the actual num-
1
ber of customers being approximately 1,165. The average water use for 1979 was
approximately 0.273 MGD and the peak day was estimated to be approximately 1.73
IIGD.
—2—
-------
The combined system has in service one 250,000 gallon elevated tank at MurreiPs
Inlet, one 300,000 gallon elevated tank at Well #6, one 250,000 gallon elevated
tank near S.C. Road #46 and Road #450, and one 20,000 gallon pneumatic tank at
Well #12. The storage has sufficient capacity to meet the average flow on a
peak day for approximately 12 hours.
FUTURE CONDITIONS
The following table gives past and projected residential equivalent customer
connections and water demands)
PAWLEY ‘S ISLAND/MURRELL ‘S INLET
WATER DEMAND ESTIMATES
Year
Connections
liaximum Month
(MGD)
Maximum Day
(MGD)
1978
1979
1990
2000
2270*
2555*
6100
8350
0.93*
1.01*
2.40
3.18
1.73
3.62
4.87
* Historical Data
Utilizing a regulatory design criterion requiring that water wells be capable
of meeting the maximum daily demand during a 16-hour pumping period, this system
operated at design capacity (1810 GPM) on at least one occasion in 1979.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consurier levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a rresent day situation. In other words, the assumption was made that
the alternative was constructed and beca;ie operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation 0 f capital and
operating costs with respect to anticipated construction schedules.
The existing supply capacity of 1810 GPM will be utilized as a basis for evalua-
ting the alternatives presented in the remainder of this report.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Ilethod
This alternative would involve the drilling of wells to replace or blend with the
existing high fluoride wells. This alternative is heavily dependent upon the
quantity and quality of low fluoride ground water available, both of which are
unknown. Therefore, for this to be a viable solution, test and water zone sampi—
-4-
-------
ing wells must be drilled near each existing well to be used for blending and
sufficient, satisfactory water located to replace or blend with the existing
well water.
Based upon discussions with U.S. Geological Survey (USGS) personnel, it is
anticipated that higher yields of good quality water are more likely to be
found by drilling near the Intracoastal Waterway as opposed to wells drilled
closer to the ocean. 3 One example is the Brookgreen Gardens ticket stand well
which yields approximately 150 GPM, has a fluoride concentration of 0.2 mg/i and
an iron concentration of less than 0.1 nig/l. 4 Discussions with the S.C. Water
Resources Cornission indicate that 75 to 100 GPM could be expected from shallow
5
wells in the area.
It appears that the best location for blending wells would be near the Litch-
field Plantation well due to its proximity with the Intracoastal Waterway. This
alternative assumes that all other high fluoride wells will be abandoned. The
100 GPM Hagley well can be used without any treatment, the blended water would
provide the remaining 1710 GPM. The Litchfield Plantation well has a fluoride
concentration of 3.0 mg/i and produces 500 GPM. To achieve a blend of 1710 GPM
with a fluoride concentration of 1.4 mg/l, it would be necessary to construct
14 shallow wells with a combined fluoride concentration of 0.75 mg/i or less.
In addition to the blending wells, the estimated cost of this alternative includes
iron sequestering equipment.
Cost Estimate
• Capital cost estimate for project design and construction $900,000
• Annual added debt service assuming 12% loan for 30 years $111,735
• Annual added operation cost using 1979 water use $ 2,730
• Total estimated added annual cost $114,465
—5—
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 30 months of the completion of required referendum, rate structure studies,
funding procurement, etc., provided only iron sequestering is required.
Operator Requi renents
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: FLUORIDE REMOVAL TREATMENT
Method
This solution would involve the treatment of the water from all existing high
fluoride wells. The treatment process which appears to be the least expensive
to reduce the fluoride concentration is the activated alumina process. This
process would involve treatment of a portion of the flow from each well and the
blending of the bypassed portion with the defluoridated water. When the treat-
ment capacity is exhausted, the unit must be regenerated and the backwash dis-
charged to the proposed sanitary sewer system. For a description of the activated
alumina process, see the Appendix entitled “Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $2,255,000
• Annual added debt service assuming 12% loan for 30 years $ 279,936
• • Annual added operation cost $ 208,000
• Total estimated added annual cost $ 487,936
-6-
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 48 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120
hours of formal training should be adequate to upgrade operator skills to the
level required by the proposed treatment system. The actual cost to the commun-
ity for this training is anticipated to be approximately $3,000 plus travel and
living expenses.
ALTERNATIVE NO. 3: REGIONAL WATER SYSTEM
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains convey the water
in a westerly direction as far as Conway, in a southerly direction as far as
Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
—7—
-------
See the Appendix entitled “Regional Water System” for a more complete descrip-
tion of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallons. At your current average dai1y demand of
273,000 gallons, your annual cost would be $293,953.
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
GCWSA PAWLEY’S ISLAND/MURRELL’S INLET COMBINED SYSTEM
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Capital
Annual Cost Data
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Regional
No. 3: Treatment
1810
2653
1810
$111,735
$265,504
$279,936
$ 2,730
$ 28,449
$208,000
$ 44.80
$115.05
$190.97
*Equivalent Residential Consumer
-8-
-------
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate $17.85
• Estimated monthly increase 3.73
Adjusted Monthly Water Rate $21.58/consumer
-9-
-------
REFERENCES
1 Meeting and discussions with Bob Barker, Director of GCWSA, and Barry Green,
Engineer with GCWSA, on January 23 and 24, 1980.
2 DHEC Water Analyses: Well #1 dated October 4, 1976; Well #2 dated October 27,
1975; Wells #3, 4 & 6 dated July 19, 1976; Well #12 dated April 2, 1980.
Parker Laboratory, Inc., Analysis, on Well #11 dated June 28, 1977.
3 Meeting and discussion with Allen Zack of USGS Conway Office, on February 5, 1980.
4 DHEC Water Analysis on Brookgreen Gardens Ticket S.tand well, taken April 2, 1980.
5 lelephone communication with Larry West of S. C. WRC Conway Office, on April 8,
1980.
6 DHEC Staff Study on Fluoride for Murrell’s Inlet and Pawley’s Island systems, both
dated April 17, 1978.
-10-
-------
FLUORIDE REDUCTION
I N
PUBLIC WATER SUPPLY
OF
GRAND STRAND WATER AND SEWER AUTHORITY
GARDEN CITY AREA COMBINED WATER SYSTEM
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE 0F CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions . . 2
Future Conditions 3
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method
Cost Estimate with Iron Sequestering 7
Cost Estimate with Iron Removal 7
Implementation 7
Operator Requirements 8
Alternative No. 2: Re3ional l!ater System
Method 8
Cost 8
Implementation 9
Operator Requirements 9
Alternative No. 3: Treat Existing tJells
Method
Cost Estimate 10
Implementation 10
Operator Requirements 10
Summary 1 1
REFERENCES . . . . . . . . . • 12
APPEND I CES
Regional Wdter System
Fluoride Treatment
Blending Graph
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tlater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 pub ic ‘,•,ater supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community i:ater supply which exceeded the
lecal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Garden City Area Combined Water System.
In addition to addressing the conceptual solution from a technical standpoint,
planning-level cost estimates are also presented. It should be noted that all
capital costs are presented in 1980 dollars and that all operating expenses were
calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
Grand Strand Water and Sewer Authority (GSWSA) is planning, or has already entered
into agreement, to purchase three existing water systems in the Garden City area
within a year and to interconnect those systems with GSWSA’s Windjammer water
system. 1 The three systems to be purchased are Jensen’s Trailer Park, Green Lakes
Mobile Home Park, and Mt. Gilead Water Company. For this report, the four water
systems will be treated as one system and will be referred to as the Garden City
Area Combined Water System of GSWSA.
Data on record with DHEC 2 relative to the existing wells which presently serve the
individual systems are listed in the following table.
GARDEN CITY AREA COMBINED WATER SYSTEM
EXISTING WELL DATA
Well
Capacity
(Gal/nm)
Fluoride
(mg/i)
Iron
(mg/i)
Storage
(Gallon)
Green Lakes
Jensen’s
‘ft. Gilead 1/1
Mt. Gilead 1/2
Windjammer
90
150
75
125
200
5.4
5.0
5.0
5.0
5.1
0.10
0.08
0.10
15,000
13,600
2,500
10,000
Data received from present system owners 3 and from the DHEC staff studies on fluo-
ride indicate that the present number of total customers served is approximately
800 of which 700 are mobile homes. Of these, the Green Lakes system’s 250
trailers are occupied primarily during the sumer months. The present annual
average water use for the combined system is estimated to be 135,000 GPD.
—2—
-------
FUTURE CONDITIONS
The future total number of customers is estimated to be 1,003. Using the
present average water use per dwelling, the future average water use is esti-
mated to be approximately 180,000 GPD.
If it is assumed that the peak day water demand will be 180% of the average
future water use during the summer, the future water deuand would be approxi-
mately 0.385 1GD. Uith that demand, the desirable minimum pumping rate
would be 400 GPM, which would allow the estimate peak day water demand to be
pumped in 16 hours. If Ameen’s niethod 5 for predicting instantaneous water demand
on the supply system is used, the estimated demand would be 600 6PM. Using this
r
as the instantaneous water supply demand, /\meen’s method of checking pressure
tank capacity indicates that a well capacity of 400 GPII should be adequate t’iith
the existing 41,100 gallons of pneumatic tank capacity.
WATER STORAGE QUANTITY VERIFICATIO1
Given:
1. 1,000 residential connections assumed as design condition.
2. Yield of new well is assumed to be 400 GPM.
3. Existing pressure tank size is 4’,lOO gallons.
4. Peak demand, tank demand, and calculation procedures are as recoriiiended by
Joseph S. Ameen in his book entitled “Community (later Systems” on Pages 50
through 55.
Calculations:
1. 1,000 residences x 0.6 GPM/resd. = 600 GPM.
2. 600 GPM - 400 6PM well yield = 200 6PM tank demand.
—3—
-------
3. 200 GPM x 20 minute demand = 4,000 gallons of stored water needed.
4. Minimum pressure tank size = 4,000 x 4 = 16,000 gallons.
5. Existing tank capacity is 41,100 gallons; therefore, existing tanks are
adequate.
—4-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for this water system. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
suits of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNI\TIVE NO. 1: DRILL UELLS FOR BLENDING
‘1ethod
The alternative would involve the drilling of new wells to replace or blend with
the existing high fluoride wells. This alternative is heavily dependent upon the
quantity and quality of shallow ground water available, both of which are unknown.
Therefore, for this to be a viable solution, test and water zone sampling wells
must be drilled near each existing well to be used and sufficient, satisfactory
water located to replace or blend with the existing well water.
—5-
-------
Since the desirable future peak day pumping rate is 400 GPF! and the present total
pumping rate is 640 GPM, it will only be necessary to produce 400 GPM of blended
water. Therefore, for this study it will be assumed that the total rate of
blended water flow at each existing well site will have to be only 62.5% of the
existing well capacity to achieve a total pumping rate of 400 GPM. The proper
blend will be achieved by replacing the existing pumps with smaller pumps of the
desired pumping rate. This will reduce the amount of low fluoride water required.
Assuming that the shallow ground water will have a fluoride concentration of 0.2
mg/i or less, the blend ratio graph in the Appendix can be used to determine the
required quantity of low fluoride water needed to blend with existing high fluo-
ride well water. TI e fc 1lowing table gives the ariount of low fluoride water re-
quired for an acceptable fluoride blend and the maximum blend water iron concen-
tration to achieve a 1.0 mg/i iron blend. The 1.0 mg/i iron concentration is
somewhat arbitrary since the critical factor for this alternative to be a low
cost solution is that the iron in the blended water must either be less than 0.3
mg/i, which appears unlikely, or be suitable for sequestering to achieve an
acceptable water. To allow a safety factor, a 1.4 r g/l fluoride concentration
has been used as the acceptable concentration.
GARDEN CITY AREA COMBINED WATER SYSTEM
BLENDING DATA
Well
Fluoride
(mg/i)
Iron
(mg/i)
Reduced
Capacity
Capacity
Iron
(mg/i)
Green Lakes
Jensens
Mt. Gilead #1
Mt. Gilead #2
Windjammer
5.4
5.0
5.0
5.0
5.1
0.10
0.08
0.10
0.00
0.10
13 GPM
24 GPM
12 GPM
20 GPM
30 GPfI
43 GPM
70 GPM
35 GPM
58 GPM
95 GPfI
1.27
1.31
1.31
1.31
1.29
—6—
-------
Based on estimates received from private contractors 6 and a discussion with
7
South Carolina Water Resources Commission personnel , it was assumed that
shallow wells would produce 60 GPtI of low fluoride water on the average. There-
fore, multiple wells and, well lots with connecting piping would be required to
serve each deep well. It was also assumed that iron sequestering units would
be required at each main well site. To indicate the impact of excessively high
iron content in the new wells, the cost of iron removal treatment has also been
estimated. However, it is beyond the scope of this study to predict whether or
not iron removal treatment would be necessary.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction $310,000
• Annual added debt service assuming 12% loan for 30 years $ 38,487
• Annual added operation cost using estimated existing water use $ 1,436
• Total estimated added annual cost $ 39,923
Cost Estimate with Iron Reiiioval
• Capital cost estimate for project design and construction $770,000
• Annual added debt service assuming 12% loan for 30 years $ 95,596
• Annual added operation cost using estimated existing water use $ 16,890
• Total estimated added annual cost $112,486
Implementati on
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendum, rate structure studies,
—7—
-------
funding procurement, etc. Should iron removal treatment become necessary, the
time would increase to 48 months.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative. However, if iron removal treatment is necessary, it is
anticipated that at least one additional staff position for water system operator
would be created.
ALTERNATIVE NO. 2: REGIONAL WATER SYSTEM
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains convey the water
in a westerly direction as far as Conway, in a southerly direction as far as
Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
See the Apper.dix entitled “Regional Water System’ t for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallons. At the current average daily demand of
-8-
-------
135,000 gallons, the annual cost for this system would be $145,361.
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
ALTERNATIVE NO. 3: TREAT EXISTING WELLS
Method
This solution would involve the treatment of existing well water to reduce the
fluoride concentration. To be consistent with the previous alternative, it was
assumed that 400 GPM would be treated. Therefore, the two Fit. Gilead wells
would be piped together and treated and the one well at llindjammer will be treated.
The treatment process which appears to be the least expensive to reduce the fluo-
ride concentration is the activated alumina process. This process would involve
treatment of a portion of the flow from each well and the blending of the bypassed
portion with the defluoridated water. tlhen the treatment capacity is exhausted, the
unit must be regenerated and the backwash discharged to the proposed sanitary
sewer system. Since stored water is limited in this community, it has been
assumed that a regeneration tank and variable speed pump would be required at each
treatment unit. For a description of the activated alumina process, see the
Appendix entitled “Fluoride Treatment”.
-9-
-------
Cost Estimate
• Capital cost estimate for project design and construction $840,000
• Annual added debt service assuming 12% loan for 30 years $104,278
• Annual added operation cost using estimated existing water use $ 62,000
• Total estimated added annual cost $166,278
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 42 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated aitirnina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level re-
quired by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
-10-
-------
GSWSA GARDEN CITY AREA COMBINED SYSTEM
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Regional
No. 3: Treatment
400
267
400
$38,487
$131,293
$104,278
$1,436
$14,068
$62,000
$ 49.90
$181.70
$207.85
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Assum-
ing that the increased annual cost for the selected alternative will be amortized
uniformly over the existing consumer population, the annual incremental increase
was calculated to be $49.90 per consumer ($4.16/month).
—11—
-------
REFERENCES
‘Telephone communication with Bob Barker, Director of GSWSA, on April 9, 1980.
2 DHEC Staff Studies on Fluoride for:
Green Lakes Mobile Home Park, dated April 17, 1978;
Jensen’s Trailer Park, dated March 30, 1978;
Mt. Gilead Water Company, dated April 19, 1978;
Windjammer Mobile Home Park, dated April 17, 1978.
3 rleetings and discussions with system owners:
Green Lakes Ilobile Home Park, on February 12, 1980;
Jensen t s Trailer Park on February 6, 1980;
Fit. Gilead Water Company on February 5, 1980;
Windjammer Mobile Home Park on January 30, 1930.
4 Clark, J. W., et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pa.
5 Ameen, Joseph S., Community Water Systems , pages 50 through 55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, forth Carolina.
6 Well yields, chemical quality, and costs estimated by Robert B. Heater, President
of Heater Well Company.
7 lelephone communication with Larry West of the South Carolina Water Resources
Commission, Conway Office, on April 8, 1980.
—12—
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tiater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
fc’rcement responsibility for the standards was requested by and subsequently
u anted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
€: public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Crystal Lakes Mobile Home Park. In addi-
tion to addressing the conceptual solution from a technical standpoint, planning—
level cost estimates are also presented. It should be. noted that all capital
costs are presented in 1980 dollars and that all operating expenses were calcu-
lated at 1979 water production and consumer levels.
—l —
-------
BACKGROUND
CONSUMERS
The Crystal Lakes Mobile Home Park water system provided service to 200 consumers,
approximately 600 people, as of April, 1978.1
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this community is not readily available. Con-
sequently, system averages developed from records of similar communities were uti-
lized as a basis for establishing assumed values which will be utilized in ensuing
sections of this report. An average daily usage of 200 gallons per connection and
a maximum daily demand factor of 180% were used to establish the following system
demand data:
o Average Daily Denand 40,000 Gallons
• Maximum Daily Demand 72,000 Gallons
Supply Requirement
Utilizing a regulatory criterion requiring that the well or wells be capable of
meeting the maximum daily demand in a 16-hour operating period, the present sup-
ply requirement was calculated to be 75 GPM.
Existing Supply
The existing supply is obtained from two deep well installations. The larger con-
sists of one 125 GPM well and one 16,000 gallon pneumatic storage tank. The other
consists of one 75 GPM well and one 10,000 gallon pneumatic storage tank. 1 Uater
2
supplied by the existing wells contains 4.08 ng/l fluoride.
—2-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Crystal Lakes Mobile Home Park. Each alternative was subsequently
evaluated to determine the most practical and least expensive method of effecting
a solution to the fluoride problem. The ensuing paragraphs of this report docu-
nient the results of the evaluations and rank the alternatives in their order of
desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is presented in 1983 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: WATER PURCHASE
Method
This alternative addresses purchasing water from the City of Myrtle Beach. The
connection would be made along U.S. Highway 17 in close proximity to Long Bay
Estates. A distribution main, constructed at the expense of the mobile home park
owner, would convey water from the city system to the mobile home park.
-3—
-------
Cost
The construction cost of Alternative No. 1 including engineering and project con-
tingency expenses has been estimated at $30,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $ 3,724
• Water Purchase 8,322
Subtotal $12,046
• Less Power Cost (Abandoned Wells) 1,046
Total Estimated Annual Cost Increase $11,000
The water purchase expense listed above was calculated at $0.57 per 1000 gallon,
the prevailing bulk rate charged by the City of Myrtle Beach. It should be noted
that the City was included in this study and that they too, will incur additional
expenses as a result of reducing the fluoride concentration of their water supply.
Assuming a uniform amortization of the cost associated with the least expensive
alternative developed for Myrtle Beach, their bulk rate would increase from
S0.57/1000 gallon to $1.64/bOO gallon. Utilizing the higher rate, Crystal Lakes’
water purchase expense was recalculated to be $23,944, bringing the total estimated
annual cost of Alternative No. 1 to $26,622.
Impl emeritation
The implementation of this alternative is solely dependent on the availability of
water from Myrtle Beach. As of this writing, the minimum time required is esti-
3
mated at 36-60 months.
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
-4-
-------
ALTERNATIVE NO. 2: TREATMENT
tie thod
This alternative addresses treatment of a portion of the flow from the existing
125 GPM well utilizing activated alumina. The system would be sized to treat
85 GPF1, the remaining 40 GPt1 would bypass treatment and be blended with the de-
fluoridated water. A liquid waste stream from the treatment unit would be dis-
charged directly to the sanitary sewer. Due to the limited amount of water
storage capacity available on this system, a regeneration tank and pump were
included in the estimated cost.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Cost
The construction cost of 4lternative 1o. 2 including engineering and project con-
tingency expenses has been estimated at $355,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 30% $ 44,070
• Operations and Maintenance 65,000
Subtotal $109,070
• Less Power Cost (Abandoned Wells) 1,070
Total Estimated Annual Cost Increase $108,000
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
36 months of completion of required referendums, rate structure studies, funding
procurement, etc.
—5—
-------
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state
license system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
CRYSTAL LAKES MOBILE HOME PARK
ALTERNATIVE SUMMARY
Alternative
Capacity
(GP 1)
‘\nnual Cost Data
Capital
Operating
Per Consumer
No. 1: Purchase
No. 2: Treatment
N/A
125
$ 3,724
$44,070
$22,898
$63,930
$133.11
$540.00
Based upon the above listed infornation, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Presuming that the increased annual cost will be amortized uniformly over the
existing consumer population, the incremental increase was calculated to be $133.11
per consumer ($11.09/month).
-6-
-------
REFERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study for
Crystal Lakes Mobile Home Park, Horry County, April 17, 1978.”
2 South Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Sample No. 626023, August 17, 1977.
3 personal communication, Jay Hood, Myrtle Beach, April 25, 1980.
—7—
-------
FLUORIDE REDUCTIOfl
IN
PUBLIC WATER SUPPLY
OF
TOWN OF EDISTO BEACH
COLLETON COUNTY, SOUTH CAROLIIIA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRItIE COMPANY and AWARE, INC.
-------
Current Demand
Projected Demand .
EXISTING SUPPLY
FLUORIDE REDUCTION
Alternative Flo. 1: Fluori
Method
Cost
Implementation .
Operator Requirements
Alternative Flo. 2: Desal
Method
Cost
Implementation
Operator Requi rements
Summary
REFERENCES
APPENDIX
Fluoride Treatment
2
2
3
4
5
5
6
6
7
7
7
7
9
TABLE OF CONTENTS
INTRODUCTION
BACKGROUND
Consumers
WATER SUPPLY REQUIREMENTS
Page
1
2
de Treatment
ting Treatment
.
-------
I NTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En—
forcerpent responsibility for the standards was requested by and subsequently
o;- nted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal iirlit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Edisto Beach. In addition
to addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
The water system serving the Town of Edisto Beach provided water to 750 consumers
as of January 29, 1980.1
WATER SUPPLY REQUIREMENTS
The Town of Edisto Beach is a resort community with several miles of public beach.
Consequently, water demand fluctuates significantly in response to seasonal changes
and day to day variations in weather conditions.
Accurate data relative to actual water demand is not readily available. Therefore,
the following data will be utilized to determine present and future water demand:
o The existing supply, 360 GPM, operates approximately 20 hours to satisfy peak
day demand.
o The incorporated section of Edisto Beach is subdivided into 1700 residential
lots, of which 750 contain permanent dwellings.
Current Demand
Maximum daily demand was assumed to be 432,000 GPD. (360 6PM x 20 hr x 60 mm/hr =
432,000 GPO). That translates to 576 GPO/connection.
Projected Demand
Based upon the current situation, maximum future daily demand was calculated as
follows:
• (1700 lots)(576 GPO) = 979,200 gal/day
• Miscellaneous Usage = 220,800 gal/day
Total = 1,200,000 gal/day
-2-
-------
EXISTING SUPPLY
The existing supply consists of three +600 feet wells that have a combined capacity
of 360 GPM. The yield from the operating wells contains approximately 4.0 mg/i fluo-
ride which exceeds the limit of 1.6 mg/l established by law.
The Town also has one abandoned well that is + 1800 feet deep. Said well is brack-
ish with a total dissolved solids (TDS) concentration of 5500 mg/l. Fluoride in
the deep well is 2.2 mg/i, iron is reported to be 8.0 mg/i 2 . It should be noted
that the sample which was analyzed to obtain the iron concentration was drawn after
the well sat idle for several years. Therefore, it is quite possible that deter-
ioration of the well casing and pump column piping contributed to the high iron read-
ing.
—3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Town of Edisto Beach. Each alternative was subsequently evaluated
to determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
sults of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: FLUORIDE TREATMENT
Method
This solution requires the construction of three separate activated alumina treat-
ment facilities, one at each existing well site. Each facility would treat a por-
tion of the existing flow which would subsequently be blended with the remaining
portion. The capacities of the three facilities are tabulated below.
-4—
-------
EDISTO BEACH
ACTIVATED ALUMINA TREATMENT CAPACITY
Facility
Treated
Untreated
Blend
Plant #1
Plant #2
Plant #3
100 GPM
55 GPI1
115 6PM
30 GP 1
25 GPM
35 6PM
130 GPM
80 GPM
150 6PM
The waste streams generated by each facility would be collected in an equalization
tank. After each regeneration, the contents of said tanks would be neutralized
(pH adjusted) and discharged to a storm sewer. A regeneration tank and pump will
not be required at these facilities.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Cost
The construction cost of Alternative No. 1 including engineering and project cofl-
tingency expenses has been estimated at $1,077,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $133,698
• Operations and Maintenance 71 ,302
Total Estimated Annual Cost Increase $205,000
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
42 months of completion of required referendums, rate structure studies, funding
procurement, etc.
—5—
-------
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state license
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination,
in order to obtain an A operating license. Approxiriately 120 hours of formal
training should be adequate to upgrade opertor skills to the level required by
the proposed treatment system. The actual cost to the comunity for this train-
ing is anticipated tobe approximately $3,000 plus travel and living expenses.
ALTERNATIVE 110. 2: DESALTING TREATMENT
Method
This solution requires the installation of a reverse osmosis (RIO) treatment facil-
ity in close proximity to the existing elevated water storage tank. The plant
would treat brackish water drawn from the abandoned well which is located at the
base of the tank. For the purpose of comparing treatment alternatives, the R/O
unit would he sized at 480 GPM. Assuming that 25% of the raw water flow will
beconie waste (brine), the output of the plant will be 360 GPM. It was also assumed
that regulatory agencies will permit the brine to be discharged to the ocean with-
out treatment.
See the Appendix entitled “Fluoride Treatment” for a description of the reverse
osmosis process.
It should be noted that this evaluation assumes that the brackish well is in good
condition. As a first step in any planning effort, the actual condition of the
well should be ascertained.
-6-
-------
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $1,100,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $136,554
O Operating Cost 185,446
Total Estimated Annual Cost Increase $322,000
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 36 months of completion of required referendums, rate structure studies,
funding procurenent, etc.
Operator Requi rements
Operator requirements are identical to those discussed under Alternative No. 1.
SU 1MARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
TOWN OF EDISTO BEACH
ALTE RFIAT IV E SUMMARY
Treatment
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Alumina
No. 2: Reverse
Osmosis
360
360
$133,698
$136,554
$ 71,302
$185,446
$273.33
$429.33
-7-
-------
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
As of January, 1980, the average annual water bill rendered for service from this
system was $109.00.l Assuming that the increased annual cost for the selected
alternative will be amortized uniformly, the average annual water bill will
increase to $382.33 ($31.86 per month).
Brackish water treatment, while being more expensive, offers the advantage of
utilizing two aquifers as a source of supply in lieu of one. Discussions with
town officials and various state agencies indicate that the aquifer presently in
use is very limited in capacity potential. If the ultimate demand of 1,200,000
GPD (1250 GPII) is to be met, a combination of waters from both 600 and 1800 foot
levels may have to be utilized.
-8-
-------
REFERENCES
1 Personal communication, Mayor Winston Brooks, Town of Edisto Beach, January 29,
1980.
Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Sample No. P—1735, April 14, 1980.
-9-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
FOREST ACRES TRAILER PARK
HURRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions 2
Estimated Peak Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Alternative No. 1: Purchase hater from GSWSA
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Drill flew Jell
Method 6
Cost Estimate 6
Implementation 7
Operator Requirements 7
Summary 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DREC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e ffo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Forest Acres Trailer Park. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Forest Acres Trailer Park water system is served by one 50 + GPM 1 well
2
which has a fluoride concentration of approximately 5.1 mg/i. One 500 gallon
pneumatic tank 2 is used for water storage.
The system serves one single family house, a four-unit apartrient, and 11 mobile
home sites, nine of which were occupied when the system was visited. 3 In addi-
tion to serving the above-mentioned 14 families, the system owners hope to
furnish water to 6 other families in the future. If it is assumed that each
dwelling will use an average of 200 GPO, the existing water use would be 2,800
GPD and the future water use would be 4,000 GPO.
ESTIMATED PEAK L4TER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 4 the future water demand would be 7,200 GPO. With that demand,
the desirable minimum pumping rate would be 7.5 GPM, which would allow the
5
estimated peak day water demand to be pumped in 16 hours. If Ameen t s method
for predicting instantaneous water demand on the supply system is used, the
estimated demand would be 86 GPM. However, this estimate is based on each
residence having four persons who use a total of from 400 to 500 GPD. Since this
7
system serves a trailer park, DUEC has indicated that 80% of Ameen’s instantan-
eous demand can be used as the estimated demand. Using this instantaneous water
supply demand, Ameen’s method 5 of checking pressure tank size indicates that a
well capacity of at least 63 GPM will be needed if the existing 500 gallon tank
is all the storage to be provided. However, a 4,864 gallon pneumatic tank capac-
—2-
-------
ity would be required if an 8.0 GPf1 well was achieved, which is estimated to be
sufficient to meet the peak day demand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 20 residential connections assumed as design condition.
2. Existing pneumatic tank size is 500 gallons.
3. Peak demand, tank demand, and calculation procedures are as recomended by
Joseph S. Ameen in his book entitled “Community Water Systems” on pages 50
through 55, except that instantaneous demand is reduced to 80% of Arneen’s
estinate.
Calculations:
1. 20 residences x 4.3 GPM/resd. xO. 8 = 68.8 GPM instantaneous demand.
2. Usable pneumatic tank volume = 500 4 = 125 gallons.
3. Tank contribution for 20 minutes = 125 20 minutes = 6.25 GPM.
4. Minimum new well size to meet instantaneous supply demand = 68.8 6PM - 6.25 =
62.55 6PM.
5. Minimum pneumatic tank capacity with 8 GPM well = (68.8 - 8) x 20 minutes x 4
4,854 gallons.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this comunity. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: PURCHASE tIATER FROM OStISA
Method
This solution would involve the installation of a master water meter and approxi-
mately 0.4 of a mile of connection water main between the Forest Acres system and
Grand Strand Water and Sewer Authority’s (GSWSA) water main in the Snails Hud Proj-
ect area. It should be noted that connection to GSUSA will not eliminate the high
fluoride problem until GSWSA corrects their own problem.
The cost of this installation was estimated by GSWSA in February, 1979 to be
approximately $17,000.1 This cost would be at least $20,000 at today’s prices.
-4-
-------
6
Based on communication with GSWSA, it appears that the rate charged for water
will be in the range of $0.50 to $0.65 per 1,000 gallons. The higher rate will
be used for cost estimating purposes. To this rate, an increase of $0.93 per
1000 gallons must be added to cover the minimum cost which GSWSA is expected to
incur in solving their fluoride problem.
Cost Estimate
• Capital cost estimate for project design and construction $20,000
• Annual added debt service assuming 12% loan for 30 years $ 2,483
• Annual added water cost, deleting power, etc. $ 1,578
• Total estimated added annual cost $ 4,061
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 18 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
ALTERNATIVE NO. 2: DRILL NEW WELL
Method
This alternative would involve the drilling of a new well to replace or blend
with the existing high fluoride well. This alternative is heavily dependent upon
the quantity and quality of shallow ground water available, both of which are
-5-
-------
unknown. Therefore, for this to be a viable solution, a test and water zone
sampling well must be drilled near the existing well and sufficient, satisfac-
tory water located to replace or blend with the existing well water.
Assuming a shallow well fluoride concentration of 0.2 mg/i, a shallow/deep blend-
ing ratio of 3.1/1 would be required to maintain a fluoride concentration of
1.4 mg/i in the combined flow. Accordingly, a blend of 48 GPM shallow to 15 GPII
deep would provide the 63 GPM required to meet the peak day demand utilizing the
existing storage tank. It should be noted that a smaller pump would be required
to reduce the deep well flow from 50 GPM to 15 GPM.
This alternative will assume that one 8 GPM well and one new 5,000 gallon pneu-
matic water storage tank will be installed. Due to the uncertainty associated
with the quality of shallow ground water, it will be assumed for cost estimation
purposes that iron sequestering and chlorination equipment with enclosures will
be required with the installation of a new well.
Cost Estimate
• Capital cost estimate for project design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added operation cost using estimated existing water use $ 50
• Total estimated added annual cost $ 5,637
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of funding procurement, etc.
—6—
-------
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the fol1owing table.
FOREST ACRES TRAILER PARK
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Purchase
Water
No. 2: New Well
N/A
8
$2,483
$5,587
$1,578
$ 50
$290.07
$402.64
Based upon the above listed infor,nation, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Presuming that the increased annual cost for the primary alternative will be
amortized uniformly, the annual incremental increase was calculated to be $290.07
per consumer ($24.17/month).
—7—
-------
REFERENCES
1 Memo from Fred H. Soland, Jr., P. E., on Forest Acres Trailer Park, Harry
County, dated February 14, 1979.
2 DHEC Staff Study on Fluoride completed in 1978.
3 Meeting and discussion with Mr. Bellamy on February 12, 1980.
4 Clark, J. W., et al., Water Supply and Pollution Control , page 35, 1971,
Internatthnal Textbook Company, Scranton, Pa.
5 Ameen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical Proceed-
ings, Post Office Box 5041, High Point,i iorth Carolina.
6 Telephone conmunication with Bob Barker, Director of GSWSA, on April 9, 1980.
7 Letter from Fred N. Soland of DHCC to Joe Wilison of JESCO dated hay 5, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
GARDEM CITY 3EACH
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
Implementation
Operator Requirements
Alternative No. 2: Regional
Method
Cost
Implementation
Operator Requirements
Alternative No. 3: Fluoride
Method
Cost Estimate
Implementation
Operator Requirements
Summary
REFERENCES
APPENDICES
Regional System
Fluoride Treatment
Blending Graph
Page
1
2
2
4
6
6
... 6
7
8
8
9
9
9
11
TABLE OF CONTENTS
INTRODUCTION
BACKGROUND
Existing Conditions
Future Conditions
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method.
Cost Estimate with Iron Sequestering
Cost Estimate with Iron Removal
. . 7
7
8
8
Uater System
Removal Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) flational
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
ç -anted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Garden City Beach. In addition to ad-
dressing the conceptual solution from a technical standpoint, planning-leve1 cost
estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUN D
EXISTING CONDITIONS
The Garden City water system has seven wells and approximately 88,000 gallons
of pneumatic tank capacity in service. Data on record with DHEC or from the
Owner on the existing wells is tabulated below.
GARDEN CITY BEACH
EXISTING WELL DATA
Designation
Capacity
(GPFI)
Fluoride
(mg/i)
Iron
(mg/i)
#1 Central
#2
#3
#4
#5 Jamestown
#6 Huntsburger
#7 Caropines
300
200
250
95
300
135
300
5.0
5.0
3.0
3.8
3.2
4.0
4.0
0.10
0.10
0.40
0.23
0.07
0.10
1.30
The Garden City water system served approximately 13192 water service customers
in 1979 who used an annual average of 0.40 FIGD. The peak three-month period
average for 1979 was 0.63 MGD and the peak day water use was estimated to be
0.98 MGD. 1 The present total well capacity is 1580 GPII.
FUTURE CONDITIONS
The Garden City water system has experienced limited growth during the last few
years. Estimates are that 100 single family residential equivalents have been
added since 1977 raising the total residential equivalents to 1990 in 1979.1
However, it has been predicted that an additional 2500 residential equivalents
may be added by the year 1990,1 due to the installation of sanitary sewers. Using
the present water demands as a guide, it was estimated that peak day water use
—2—
-------
in 1990 would be approximately 2.2 MGD. The present pumping capacity could
conceivably meet that demand; accordingly, treatment or replacement of the
present pumping capacity has been selected as the sizing criterion for this
report.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction al-
ternatives for this conii unity. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
suits of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the conimunity’s present fiscal position. Recognizing
that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Method
This alternative would involve the drilling of wells to replace or blend with the
existing high fluoride wells. This alternative is heavily dependent upon the
quantity and quality of low fluoride ground water avai1able both of which are
unknown. Therefore, for this to be a viable solution, test and water zone sampl-
ing wells must be drilled near each existing well to be used for blending and
sufficient, satisfactory water located to replace or blend with the existing
well water.
-4—
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
GRAND STRAND WATER AND SEWER AUTHORITY
SOCASTEE AREA COMBINED WATER SYSTEM
HORRY COUFITY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY AND AWARE, INC.
-------
TABLE OF CONTENTS
INTRODUCTION .
BACKGROUND
Existing Conditions . . . . . . . . . . . . . . .
Future Conditions
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method 4
Cost Estimate with Iron Sequestering
Cost Estimate with Iron Removal .
Implementation
Operator Requirements
Alternative No. 2: Treat Existing Wells
Method
Cost Estimate
Implementation
Operator Requirements
Alternative No. 3: Regional Water System
Method
Cost . . . . . . . . . . . . . . .
Implementation
Operator Requirements
Sunmary .
REFERENCES
APPENDI CES
Regional Water System
Fl uori de Treatment
Blending Graph
Page
1
2
3
6
6
6
7
7
8
8
8
8
• . 9
8
8
9
10
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tlater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC OHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Socastee Area Combined Water System. In
addition to addressing the conceptual solution from a technical standpoint, plan-
ning-level cost estimates are also presented. It should be noted that all capital
costs are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Socastee Area combined water system includes the following individual water
systems: Green Acres, Cimarron Plantation, Watson’s Riverside and HUD projects,
Watergate, Small’s HUD project, Highway 707 project, Highway 544, and the Forest
Brook - Cypress Creek Subdivisions. The Highway 544 system presently and/or
formerly obtained its water from the Conway Rural water system which has a fluo-
ride concentration of approximately 4.0 mg/i. 1 All other syster is were originally
served by their own wells which now supply the combined water system. The approx-
2 2
imate pumping rates, hydropneumatic water tank sizes, fluoride and iron concen-
trations 1 of the wells are listed in the following table.
SOCASTEE AREA COMBINED WATER SYSTEM
EXISTING SUPPLY DATA
Well
Capacity
(Gal/Mm)
Fluoride
(mg/i)
Iron
(mg/i)
Storage
(Gallon)
#1 Booster Pump
at C.R.
#2 Watson’s River—
side
#3 Green Acres
#4 Cimarron
#5 Watson’s HUD
#6 Watergate
#7 Forest Brook
#8 Small’s HUD
200
55
300
50
500
40
500
200
4.0
4.0
3.9
4.0
3.0
5.1
4.7
5.0
0.1
0.3
0.1
0.1
0.1
0.1
0.2
0.2
None
10,000
10,000
10,000
10,000
20,000
10,000
The combined system served an average of approximately 1,571 water service connec-
tions in 1979, of which over 98% were residential connections. 3 Average demand in
—2—
-------
1979 was approximately 338,200 GPO and a peak monthly average of 387,700 GPO
occurred in July.
FUTURE CONDITIONS
Future water demand estimates were obtained from a consulting engineer’s report
dated May 2, 1979.1 A substantial growth in population and service connections
was predicted in that report. The average day water demand for the combined sys-
tems was predicted to be approximately 1.65 I1GD for 1990 and 2.69 MGD for the
year 2000. The peak day water demand for the combined system was predicted to be
double the average day water demand which would be 3.30 MGD for 1990 and 5.375
tIGD for the year 2000. Uater main installations to interconnect the previously
listed systems are planned and expected to be in service by 1982. Also, a 250,000
gallon elevated water storage tank has been proposed for installation by 1982 for
the Forest Brook/Highway 544 system service area.
Another water system proposed by GSt 1SA would be along Highway 90 from the junction
of Highway 501 near Conway to an area approximately one and one half miles to the
west of Nixonville. Since this is a l)roposed system, it was not included in this
study.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for the subject water system. Each alternative was subsequently evaluated
to determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
sults of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assunption was made that
he alternative was constructed and b came operational during the 1980 calendar
:.ear. By utilizing current data, coriparison of the various alternatives is placed
r a proDer p -spective .. Lh the com iunity’s present fiscal position. Recognizing
t 1 at the COst ata is presented ii 1980 dollars, it is recommended that initial
planning o ny ternative include a reevaluation of capital and operating costs
‘ ith respect to anticipated construction schedules.
.TERNATIVE rIO. 1: DRILL UELLS FOR BLEIIDING
ethod
This alternative would involve the drilling of wells to replace or blend with the
existing high fluoride wells. This alternative is heavily dependent upon the
quantity and quality of shallow ground water available, both of which are unknown.
Therefore, for this to be a viable solution, test and water zone sampling wells
must be drilled near each existing well to be used and sufficient, satisfactory
water located to replace or blend with the existing well water.
-4-
-------
Assuming that the shallow ground water will have a fluoride concentration of
0.2 mg/i or less, the blend ratio graph in the Appendix can be used to determine
the required quantity of shallow well water needed to blend with existing high
fluoride well water. The facilities proposed in this alternative would, if
constructed, provide a 1500 GPM supply which would be approximately equal to the
existing high yield well capacity.
The following table indicates the amounts of shallow well water (0.2 mg/i fluoride)
that can be blended with selected deep wells to maintain a blended fluoride concen-
tration of 1.4 mg/i. It should also be noted that the capacity of the existing
wells would be reduced and that a maximum shailo well iron concentration is listed.
The capacity reduction would be effected by replacing the existing pumps. The max-
imum iron concentration would provide a blended supply having an iron level of
1.0 mq/1 which can usually be sequestered by adding polyphosphates (chemicals).
Iron concentrations in excess of 1.0 mg/i should be expected to require treatment.
SOCASTEE AREA C0f1B NED WATER SYSTEM
BLENDING DATA
Well
Fluoride
(mg/i)
Iron
(mg/l)
Reduced
Capacity
(Gal/Mm)
Capacity
(Gal/Mm)
Iron
(mg/l)
#3
#5
#7
#8
3.9
3.0
4.7
5.0
0.10
0.10
0.20
0.20
98
216
134
50
202
284
366
150
1.44
1.68
1.29
1.27
Iron sequestering units were assumed to be needed at each main well site. Based on
estimates received from private contractors 4 and a discussion with the South Carolina
5
Water Resources Commission , it was assumed that shallow wells produce 75 6PM each;
—5—
-------
therefore, multiple wells and well lots with connecting piping would be required
to serve each deep well. Cost data for systems with and without iron removal
treatment have been prepared and are presented below. tt is beyond the scope of
the study to determine whether or not iron removal treatment would be needed.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction $900,000
Annual added debt service assuming 12% loan for 30 years Slll,735
e Annual added operation cost using 1979 water use $ 3,382
Total estimated added annual cost $115,117
Cost Estimate ntI iror Renoval
Capital cost estimate for project design a’ d cc. 3truction Si ,900,000
nua a d d debt so e a3suming 12 1o n for 30 years S 235,885
t Pnnual added crcrat on ccst using 1979 water use 13, 41
Total e tir ated added annual cost S 239 ,32
imp1ementa i on
It 1 as beert estimated that design, securing of pemits and approvals, a,dvertise-
r ent, contract execution, and construction of this alternative can be accomplished
within 30 months of the completion of required referendum, rate structure studies,
funding procurement, etc. It is estimated that the total tir 1 ie would increase to
54 months if iron removal treatment is required.
Operator Requi renents
Operator requirements for this system are not expected to change as a consequence
of this alternative. However, if iron removal treatment is necessary, it is antici-
pated that a staff position for at least one additional water system operator would
he created.
-6-
-------
ALTERNATIVE NO. 2: TREAT EXISTING WELLS
Method
This solution would involve the treatment of existing well water to reduce the
fluoride concentration. To be consistent with the previous alternative, it will
be assumed that only the high yielding wells, Wells #3, 5, 7 and 8 will be treated.
Each well would have its own treatment unit. The treatment process which appears
to be the least expensive to reduce the fluoride concentration is the activated
alumina process. This process would involve treatment of a portion of the flow
from each well and the blending of the bypassed portion with the defluoridated
water. When the treatment capacity is exhausted, the unit must be regenerated and
the backwash discharged to the sanitary sewer system which has been proposed. For
a description of the activated alumina process, see the Appendix entitled “Fluoride
Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $1 ,590,000
o Annual added debt service assuming 12% loan for 30 years $ 197,383
• Annual added operation cost using 1979 water use $ 156,000
• Total estimated added annual cost $ 353,383
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
nient, contract execution, and construction of this alternative can be accomplished
within 48 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed “A” operator for those systems em-
ploying activated alumina fluoride removal technology. The present state license
—7-
-------
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination, in
order to obtain an A operating license. Approximately 120 hours of formal train-
ing should be adequate to upgrade operator skills to the level required by the
proposed treatment system. The actual cost to the community for this training is
anticipated to be approximately $3,000 plus travel and living expenses.
ALTERNATIVE F lU. 3: REGIONAL WATER SYSTEM
flethod
This alternative addresses the construction of a major water treatment facility on
the- Great ree [ lee Rivet’ rear Bucksport. Distribution nains would convey the water
in a westerly direction as far as Conway, in a southerly direction as far as
‘av:ley’s Island, and in a northerly direction aS far as North Myrtle Beach.
:arage:ien: and operation of the rro osed system would be effected under a ,jcint
greeinent of aL political subdivisions involved.
:ch community system served would purchase water on a bu k basis for resale to
•cs consumers.
5ee the Appendix entitled “Regional Water System” for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallons. At the current average daily demand of
338,200 gallons, the annual cost for this system would be $364,157.
-8-
-------
Implenientati on
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
SU 1MARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
GSWSA SOCASTEE AREA COMBINED WATER SYSTEM
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating.
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Treatment
No. 3: Regional
1,500
1,500
2,292
$111,735
$197,383
$328,914
$ 3,382
$156,000
$ 35,243
$ 73.28
$224.94
$231.80
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Assum-
ing that the increased annual cost for the selected alternative will be amortized
uniformly over the existing consuner population, the annual incremental increase
was calculated to be $73.28 per consumer ($6.11/month).
—9—
-------
REFERENCES
Pre1iminary Engineering Report on GSWSA’s water systems between Conway and
Myrtle Beach, by CH2M Hill, dated May 2, 1979.
2 DHEC Staff Studies on Fluoride for the various individual water systems, dated
March 2 and 6, 1978 and July 11, 1978.
3 Data sheets provided by GSWSA listing actual billing records from November 20,
1977 through January 11, 1980.
4 We11 yields, chemical quality, and costs estimated by Robert B. Heater, President
of Heater Well Company.
5 Teiepiione communication with Larry West of the South Carolina Water Resources
Cornission, Conway Office, on April 8, 1980.
-10-
-------
FLUORIDE REDUCTION
I N
PUBLIC HATER SUPPLY
OF
TOWN OF HEMMINGWAY
WILLIAMSBURG COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLIUA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Projected Demand 2
Current and Projected Supply Requirements 3
EXISTIJ G SUPPLY 3
FLUORIDE REDUCTION
Alternative No. 1: Blending
Method 4
Cost
Implementation 6
Operator Requirements 6
Alternative No. 2: Treatment
Method 6
Cost 7
Implementation . . . . 7
Operator Requir nents 7
Summary g
REFERENCES
APP EUD IX
Fluoride Treatment
-------
I NTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) t ational
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
rited to the South Carolina Department of Health and Environmental Control
(S DHEC). nvestigations conducted by the State revealed that approximately
60 public t;azer supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected coninunities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DIIEC, is a direct outgrowth of that
effort.
in January, 1980. a study of each co imunity water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Hemniingway. In addition to
addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
_1_
-------
BACKGROUND
CONSUMERS
The water system serving the Town of Hemmingway provided water to 532 consumers,
1
approximately 1700 people, as of April, 1978.
Williamsburg County is expected to experience continued industrial growth during
the forseeable future. As a consequence of that growth, the consumer population
of the Henimingway water system is expected to grow. In lieu of actual planning
dati which is not readily available, an annual growth rate oF 5% will be assumed
in the ensuing sections of this report.
WATER SUPPLY REQUIRENEtITS
Current Demand
The aver ge d iiy water usage for calendar 1979 was estimated at 212,500 GPD That
translates to an average of 400 GPDjconnection. Maximum average daily demand
3
was considered to be approximately l80 of average daily usage. Accordingly,
the current water demand placed on the system has been established as follows:
• Average Daily Demand 212,500 Gallons
• Maximum Daily Demand 382,500 Gallons
Projected Demand
Utilizing the previously assumed 5% annual growth rate in consumer population,
projected water demand has been estimated and is presented in the following table.
-2-
-------
TOWN OF HEMMINGWAY
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
1995
2000
212,500
271,100
345,900
441,368
563,200
382,500
488,000
622,600
794,500
1 ,013,700
listed supply requirements were calculated utilizing a regulatory design
requiring that the well or wells be capable of meeting the maximum daily
a 16—hour operating period. Said values are as follows:
— 398 GPM
- 508 GP
- 648 rWI
- 828 GPM
— 1 ,056 GPfl
EXISTING SUPPLY
The existing water supply consists of two deep wells having a combined rated
capacity of 785 6PM. As of February 4, 1980, the #2 well, which is rated at 235
2
6PM, was not in use. Based upon the present requirement of 398 6PM, the existing
production capability of the #1 well (550 GPM) is adequate. It is noted, however,
that water produced by the existing wells contains 1.8 mg/i fluoride which exceeds
4
the limit of 1.6 mg/I established by law.
Current and Projected Supply Requirements
The below
cr1 ten on
demand in
• 1980
• 1985
c 1990
• 1995
s 2000
—3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Town of Hemmingway. Each alternative was subsequently evaluated
to determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
sults of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other wards, the assuription was nade that
the alternative was cnstructed and became operational during the 1980 calendar
year. By util 5 zing current data, comparison of the various alternatives is placed
in a prorer crspecti’.e uith the c 1’r!uni:y’s present fiscal position. Recognizing
that the c t d ta is presented n’ R20 dollars, it is reconrended that in tiai
ilanning of or 1 ’ a 1 ternative include a reevaluation o f capital and operating costs
with respect to anticipated construction sóedules.
ALTERNATIVE rio. 1: BLEN Ufl IG
Ile -thod
Fluoride reduction can be achieved by drilling a series of shallow wells and blend-
ing their yield with that of the existing deep wells. Assuming a fluoride concen-
tration of 0.1 mg/I in the proposed shallow wells, a shallow/deep mix of 1.00 GPM/
2.33 GPM will result in a blend having a fluoride concentration of 1.4 mg/l.
-4-
-------
This alternative addresses construction of shallow blending wells at Well #1.
Well #2 was not considered because it is out of service and usage projections
indicate that the increased capacity (shallow plus deep) of Well #1 will satisfy
community requirements through the year 2000. Utilizing a blend ratio of 1
shallow/2.33 deep, the required shallow well capacity was determined to be 235
G PM.
Lacking accurate data on the quantity of shallow ground water available in the
Henimingway area, quantity was conservatively estimated at 50 GPM per well, requir-
ing construction of five wells.
Sufficient iron to cause aesthetic problems, such as staining of plumbing fixtures,
should be expected in the proposed shallow wells. With the favorable ratio of
deep/shallow well water that will be utilized in this system, it was assumed that
the iron could be sequestered and then diluted sufficiently to preclude the occur-
rence of iron related nuisance problems. Feeding a solution of polyphosphates
(chenical) to the shallo a wells will provide an economical means of controlling
red water. The chemical is purchased dry in 50 or 100 pound bags and mixed with
water to for i a solution. The mixture is then injected into the system by a
sniaji pumo.
A schenatic diagram of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recommended is as follows:
• Five 50 GP 1 shallow wells. Each well should be equipped with a vertical
turbine pump set up to operate simultaneously with the deep well pump.
• One concrete valve pit constructed at the intersection of the deep and
shallow well lines. The pit should contain meters and valves on both
supply lines. The chlorine injection point should be in the tee or the
line leaving the pit.
-5-
-------
• Polyphosphate mixing and feed facilities. The concept presented herein
utilizes a single chemical feed point in the common main leading from the
shallow wells. However, it should be noted that iron must be in a soluble
form for sequestering to be effective, and that pumping and/or conveyance
may cause the iron to precipitate. Should that situation occur, the chem-
ical feed point may have to be moved or iron treatment may become necessary.
Cost
The construction cost of Alternative l b. 1 including engineering and project con-
tingency expenses has been estimated at $205,000. Annual costs are summarized
below.
• Debt Service or a 30-Year Loan at l2 ? 525 ,449
• Cherilcal Cost 251
Total Estimated Annual Cost Increase $25,700
rnpl ement tion
)esigrt, securing perwits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requi rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
ALTERUATIVE HO. 2: TREATMENT
1 ’ e thod
This alternative addresses treatment of a portion of the flow from the existing
500 GPM well utilizing activated alumina. The system would be sized to treat
-6—
-------
PROPOSED
POLYPHOSPHATE FEED
rx
x
x
PROPOSED 5 5 ACRE
WELL FIELD
FIGURE 1
/
/
/
EXISTING
5O OOO GAL.
TANK
\
/
/
/
—
— 1 EXISTING
I BOOSTER
1% / PUMP
‘S —
-I-
SCHEMATIC DIAGRAM OF
PROPOSED WATER SUPPLY ADDITIONS
AT
EXISTING
550 GPM
WELL
PROPOSED
CONCRETE
VALVE PIT
PRoPosEp WELL
$ (5 Reqd.)
x
PROPOSED
FEED LINE
_L
,
TOWN OF HEMMINGWAY
-------
125 GPM, the renaming 375 GPM would bypass treatment and be blended with the
defluoridated water. A liquid waste stream from the unit would be discharged
to a waste equalization tank. Periodically the contents of said tank would
be trucked to the Pee Dee River or one of its tributaries for disposal.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Cost
The construction cost of Alternative rIo. 2 includinq engineering and project con-
tingency exponses has been estimated at $435,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $ 54,000
• Operations and f aintenance 52,000
Total Estimated Annual Cost Increase $106,000
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
36 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operathr for those systems
employing activated alumina fluoride removal technology. The present state license
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination, in
order to obtain an A operating license. Approximately 120 hours of formal training
-7-
-------
should be adequate to upgrade operator skills to the level required by the pro-
posed treatment system. The actual cost to the community for this training is
anticipated to be approximately $3,000 plus travel and living expenses.
SUMIIA RY
The alternatives which were evaluated during the course of this study are sunima—
rized in the following table.
TOWN OF HEMMINGWAY
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Treatment
785
500
$25,449
$54,000
$ 251
$52,000
$ 48.30
$199.25
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate 1 $9.60
• Estimated monthly increase 4.03
Adjusted Monthly Water Rate $13.63/consumer
-8-
-------
REFERENCES
1 5outh Carolina Department of Health and Environmental Control, “Staff Study for
The Town of Hemmingway, Williamsburg County”, April 17, 1978.
2 Personal communication, Mr. Cecil Kimery, Town of Hemmingway, February 4, 1980.
3 South Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Saiiiple number R06148-1566 , June 6, 1978.
4 Clark, J. W., et al., Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
-9-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
INLET OAKS VILLAGE
GEORGETOUN COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Estimated Peak Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Mternative No. 1: Drill ew Well
Method
Cos’. Estin t 5
Ir.pi er’tat1c.n 5
OpE c ‘. R . qu 1 N ts 5
?l t ’ t’ ‘.‘ - o . 2: P’ . rch se h’o GCUS, \
6
Cc c 1. cate 6
Imp 1entation 7
Opera:o” Require r.ents 7
Eunmary 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tiater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DREC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC OHEC, is a direct outgrot th of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution tothe reduc-
tion of fluoride in the water supply of Inlet Oaks Village. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
— l —
-------
BACKGROUND
EXISTING CONDITIONS
The Inlet Oaks Village water system has one 200 GPM well and one 10,000 gallon
pneumatic water storage tank in service. The well is reported
fluoride concentration of approximately 6.0 mg/i. The water system is approxi-
mately 1,800 feet away from a water line owned by the Georgetown County Water
and Sewer Authority’s Murreil’s Inlet system.
Water use in this system is not metered. The system has 100 approved mobile
home sites 90 to 95% of which were filled when the park was visited. The owner
advised that the trailers were owned primarily by retired couples. Assuming
the trailer park is full and average use during the summer is 200 GPO per trailer,
the estin’ated average daily water demand would be 20,000 GPD.
ESTIMATED PEAK WATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 3 the water demand would be 36,000 GPD. tjith that denand, the
desirable minimum pumping rate would be 37.5 GP 1, which would allow the
estimated peak day water demand to be pumped in 16 hours. If Ameen’s method 4
for predicting instantaneous water demand on the supply system is used, the esti-
mated demand would be 200 GPM. However, this estimate is based on each residence
having four persons who use a total of from 400 to 500 GPO. Since this system
serves a trailer park, DHEC has indicated 6 that 80% of Ameen’s instantaneous
demand can be used as the estimated demand. Using this instantaneous water supply
demand, Ameen’s method 4 of checking pneumatic tank size indicates that a well
—2-
-------
capacity of 37.5 GPM, the minimum peak day pumping rate, should be adequate
with the existing 10,000 gallon tank.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 100 residential connections assumed as design condition.
2. Yield of new well is assumed to be 37.5 GPM.
3. Existing pressure tank size is 1O,O O gallons.
4. Peak demand, tank demand, and calculation procedures are as recomended by
Joseph S. / aiieen in his book entitled “Community Water Systems” on pages 50
through 55, except that instantaneous demand is reduced to 80% of Ameen’s
estimate.
Calculations:
1. 100 residences x 2.0 GPM/resd. x 0.8 = 160 GPM.
2. 160 GPM - 37.5 GPM well yield = 122.5 GPM tank demand.
3. 122.5 GPM x 20 minute demand = 2450 gallons of stored water needed.
4. Minimum pressure tank size = 2450 x 4 = 9800 gallons.
5. Existing tank size is 10,000 gallons; therefore, tank is adequate.
—3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this comunity. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desira-
bill ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL NEW WELL
Method
This alternative would involve the drilling of a new well or wells to replace
or blend with the existing high fluoride well. Since the existing well has such
a high fluoride concentration, from 3.2 to 3.8 gallons of low fluoride water would
be needed for blending to achieve a safe, acceptable fluoride concentration. A
-4-
-------
replacement well would be more acceptable if sufficient and suitable water can
be located. If the new well yields less than 37.5 GPM but more than 29 GPM,
then blending by replacement of the existing wells pump could be used. Obviously,
this alternative is heavily dependent upon the quantity and quality of shallow
ground water available, both of which are unknown. Therefore, for this to be a
viable solution, a test and water zone sampling well must be drilled and suffi-
cient, satisfactory water located.
For this alternative, it will be assumed that one new 29 GPM well with iron se-
questering equipment and a replacement pump for the existing well will be required
to achieve an acceptable water.
Cost Estimate
• Capital cost estimate for project design and construction $40,000
• Annual added debt service assuming 12% loan for 30 years $ 4,966
• Annual added operation cost using 1979 estimated water use $ 200
o Total estimated added annual cost $ 5,166
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
—5-
-------
ALTERNATIVE NO. 2: PURCHASE WATER FROM GCWSA
Method
This alternative would involve the installation of a master water meter and
roughly 1800 feet of connection main between the Inlet Oaks system and the
Georgetown County Water and Sewer Authority’s (GCWSA) Murrell’s Inlet system.
It should be noted that connection to GCWSA will not eliminate the high fluoride
problem until GCWSA corrects their own problem.
5
GCWSA has advised that they should have the following service connection and
water rates in effect by the end of June, 1980:
• 3/4” residential connection fee
• Minimum residential service rate
• Charge for all water used
• 3” commercial tap and meter installation fee
$320
$6. 47/month
$0.97/bOO gallons
$2,000
Q Commercial water service rates are assumed to be basically the same as the
residential rates.
In addition to the above, an increase of approximately $1.15 per 1000 gallons
must be added to cover the m imum cost which GCWSA is expected to incur in solv-
ing their fluoride problem.
Cost Estimate
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added water cost, less power cost, with existing use
s Total estimated added annual cost
$25,000
$ 3,104
$21 ,800
$24,904
-6-
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of funding procurement, etc.
Qperator Regui rements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
INLET OAKS
ALTERNATIVE SUMMARY
Alternative
Capacity
(6PM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Purchase
Water
37.5
N/A
$4,966
$3,104
$ 200
$21,800
$ 54.38
$262.15
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Presum-
ing that the increased annual cost will be amortized uniformly over the existing
consumer population, the annual increnental increase was calculated to be $54.38
per consumer ($4.53/month).
-.7-
-------
REFERENCES
1 DHEC Staff Study on fluoride problem in Inlet Oaks Village, completed in 1978.
2 Meeting and discussion with Henry Burrough, Jr. on February 7, 1980.
3 Ciark, J. W., et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pa.
4 Ameen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, North Carolina.
5 lelephone conversation with Barry Green of Georgetown County Water and Sewer
Authority, on April 15, 1980.
6 Letter from Fred H. Soland of DHEC to Joe Wilison of JESCO dated May 5, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
ISLE OF PALMS
CHARLESTOU COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRI 1E COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
I NTRODUCT ION 1
BACKGROUND
Consumers 2
Water Supply Requirements. . . . . . . . . . . . . 2
Existing Supply 2
FLUORIDE REDUCTION
Alternative No. 1: Blending
Method 3
Cost 4
Implementation 5
Operator Requirements 5
Alternative No. 2: Treatment
Method 5
Cost 5
Implementation 6
Operator Requirements 6
Summary 6
REFERENCES 8
APPENDIX
Fluoride Treatment
-------
I NTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tlater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC OHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each comunity water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual so}ution to the reduc-
tion of fluoride in the water supply of Isle of Palms. In addition to addressing
the conceptual solution from a technical standpoint, planning—level cost estimates
are also presented. It should be noted that all capital costs are presented in
1980 dollars and that all operating expenses were calculated at 1979 water produc-
tion and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
The water system serving the Isle of Palms community provided water to 1,439
consumers, approximately 5,000 people, as of January 28, 1980.1
WATER SUPPLY REQUIREMENTS
The Isle of Palms is a resort community with several miles of public beach. Con-
sequently, water demand fluctuates significantly in response to seasonal changes
and day to day variations in weather conditions.
Accurate data relative to actual water demand is not readily available. There-
fore, the remainder of this report will be premised on the assumption that the
existing capacity of 1,700,000 gallon/day must be maintained. 2
EXISTING SUPPLY
The water supply for the Isle of Palms presently consists of 14 shallow well
stations and one deep ie1l. Four of the shallow well systems are chlori-
nated and pumped directly into the distribution system. Those four shallow
well systems are generally located on the eastern end of the island. The ten
remaining shallow well stations pump into one common transmission main which con-
veys the shallow well water to the site of the deep well where the two sup-
plies are blended and discharged into two ground level storage tanks. The
ground level storage tanks, which have a combined capacity of 870,000 gallons,
act as a suction reservoir for several booster pumps that feed the distribution
system. Also constructed on the site of the ground storage reservoirs, is one
150,000 gallon elevated water storage tank which rides on the system.
—2-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Isle of Palms Water Company. Each alternative was subsequently
evaluated to determine the most practical and least expensive method of effecting
a solution to the fluoride problem. The ensuing paragraphs of this report docu-
ment the results of the evaluations and rank the alternatives in their order of
desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: BLENDING
1ethod
Blending deep and shallow well water in the proper proportions will reduce the
fluoride concentration in the community’s water supply to acceptable levels.
Based upon a deep well fluoride concentration of 4.7 mg/l and a shallow well con-
centration of 0.8 mg/l, blending ratios were calculated and are presented in the
following table.
—3—
-------
ISLE OF PALMS
DEEP/SHALLOW BLENDING RATIOS
Blend Ratio
(deep/shallow)
Flow Ratio
(deep/shallow)
Fluoride
Concentration
1.0/5.5
1.0/4.6
1.0/3.9
153 GPM/847 GPM
179 GPM/82l GPM
204 GPM/796 GPM
1.4 mg/i
1.5 mg/i
1.6 mg/i
The existing supply capacity of 1,700,000 gallons of water per day translates
to approximately 1200 GPM. The water company presently discharges approximately
200 GPM, the yield of four shallow well stations, directly into the distribution
system. The remaining 1000 GPM must be generated by blending a portion of the
deep well capacity with a series of shallow wells. Based upon a blended fluo-
ride concentration of 1.4 mg/l, the required shallow well capacity is 847 GPM.
(See Table above). Accordingly, this alternative mandates the construction of
7 additional shallow well stations.
The success of blending is dependent upon control of the flow from the deep well.
Existing meters and valves can be utilized to throttle the deep well to provide
a flow that is properly proportioned to the shallow well yield. However, it
should be noted that the adaptability of the existing deep well pump to function
in a throttled mode of operation is questionable. It is beyond the limited scope
of this study to fully evaluate the effect of the significantly reduced pump out-
put. The reader is therefore cautioned that it may become necessary to modify or
replace the existing unit to consistently maintain flow rates less than 200 GPM.
Cost
Facilities included in the estimated capital cost of this alternative are the
addition of seven shallow well stations and modification of the existing deep well
-4-
-------
pump. The estimated construction cost of Alternative No. 1 including engineer-
ing and project contingency expenses has been estimated at $340,000. Annual debt
service expense on that amount calculated at 12% for 30 years is $42,207. Total
system operating costs would remain approximately the same.
ImplementatIon
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
ALTERNATIVE NO. 2: TREATMENT
Method
This alternative addresses treatment of a portion of the flow from the existing
deep well utilizing activated alumina. The system will be sized to treat 800 6PM,
the remaining 200 6PM will bypass treatment and be blended with the defluoridated
water. A liquid waste stream from the unit will be discharged to a wastewater
equalization tank. The contents of said tank will be slowly drained to the sani-
tary sewer system.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $665,000. Annual costs are sumarized below.
—5-
-------
• Debt Service on a 30-Year Loan at 12% $82,553
• Operations and Maintenance 72,447
Total Estimated Annual Cost $155,000
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract
negotiation and award, and construction of this alternative can be accomplished
within 36 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an A operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
ISLE OF PALMS
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Treatment
1000
1000
$42,207
$82,553
-
$72,447
$ 29.33
$107.71
-6-
-------
Based upon the above listed information, Alternative rIo. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate 1 $6.50
• Estimated monthly increase 2.46
Adjusted Monthly Uater Rate $8.96/consumer
—7—
-------
REFERENCES
Personal comunication, William Connelly, Isle of Palms Water Company, January 28,
1980.
2 South Carolina Department of Health and Environmental Control, “Staff Study for
Isle of Palms, Charleston County,” undated.
-8-
-------
FLUORIDE REDUCTION
I P1
PUBLIC JATER SUPPLY
OF
JA’IESTOWr I
BERKELEY COUNTY, SOUTH CAROLINA
JULY, 193’)
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AriD ENVIRONMENTAL CONTROL
Preoared By
A Joint Venture of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
MC KG ROUND
Consumers 2
WATER SUPPLY REQUIREMEffTS
Current Demand 2
Current and Projected Supply Requirements 3
EXISTING SUPPLY 3
FLUORIDE REDUCTION
Flethod 4
Cost 5
Implementation 6
Operator Requirenents 6
REFERENCES 7
-------
I f’ITRODUCT ION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives f’or each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Jamestown. In addition to addressing
the conceptual solution from a technical standpoint, planning-level cost esti-
mates are also presented. It should be noted that all capital costs are presen-
ted in 1980 dollars and that all operating expenses were calculated at 1979 water
production and consumer levels.
—1—
-------
BACKGROUND
CONS UMERS
The water system serving the Town of Jamestown provided water to 90 consumers,
1
approximately 315 people, as of March, 1978.
Population projections for the Planning District 204, of which Jamestown is a
part, were obtained from the Berkeley Charleston Dorchester Council of Governments.
Said projections were utilized to develon consumer projections for the Town.
Recognizing that the Town is the most densely populated area in the district, the
district growth percentages were applied to the existing consumer population to
develop orojected svsteni qrowth. The comoutations that were made are summarized
in the following table.
TOWN OF JAMESTOUN
CONSUMER POPULATIOF4 PROJECTIONS
Year
Population*
Projection
% Change
Consumers
1980
1985
1990
1995
5,197
5,472
5,424
5,324
-0-
5.3
0.9
1.8
90
95
94
92
*Population projection for the entire 204 Planning District
“lATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this community is not readily available.
Consequently, system averages developed from records of similar communities were
utilized as a basis for establishinq assumed values which will be utilized in
—2—
-------
ensuing sections of this report. An average daily usage of 160 gallons per
connection, a maximum daily demand factor of 180%, and the above listed consumer
population, were used to establish system demand data which is summarized in the
following table.
TOUN OF J MESTO’Ifl
PROJ ECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
14,400
25,900
1985
15,200
27,400
1990
15,000
27,000
1995
14,700
26,500
Current and Projected $urrnly Requirements
The below listed supply requirements were calculated utilizing regulatory design
criterion requiring that the well or wells be capable of meeting the maximum
daily demand in a 16-hour operating period.
• 1980 — 27 GPM
• 1985 - 29 GPM
• 1990 — 28 GPM
• 1995 - 28 GPM
EXISTING SUPPLY
The existing water supply consists of one deep well having a rated capacity of
120 GPM. Based upon the present requirement of 27 GPFI, the existing production
capability is adequate. It is noted, however, that water produced by the exist-
ing well contains 2.1 mg/l fluoride which exceeds the limit of 1.6 mg/i established
1
by 1
—3-
-------
FLUORIDE REDUCTION
METHOD
Based upon available information, the most practical and least expensive method
of effecting a fluoride reduction in the town’s water supply is to blend water
from a shallow aquifer with that of the existing deep well. Assuming a fluoride
concentration of 0.1 mg/i in the shallow well, a shallow/deep mix of 60 GPM/120
GPr I will result in a blend having a fluoride concentration of 1 .4 mg/l. The Town
presently owns a shallow well which served as a source of drtllinq water during
the construction of the deep well. 2 It is quite possible that said shallow well
can be equipped with a pump and utilized as a source of blending water. With the
operation of a shallow well, disinfection and iron content require consideration.
Shallow wells are generally nore suscertible to bacterial contamination than are
deeo wells. Consequently, the chlorinated shallow well water should be detained
in a pressure contact tank for 30 minutes prior to being blended with the deep
well water.
Sufficient iron to cause aesthetic problems, such as staining of plumbing fixtures,
should be expected in the proposed shallow wells. ‘Jith the favorable ratio of
deep/shallow well water that will be utilized in this system, it was assumed that
the iron could be sequestered and then diluted sufficiently to preclude the occur-
rence of iron related nuisance problems. Feeding a solution of polyphosphates
(chemical) to the shallow wells will provide an economical means of controlling
red water. The chemical is purchased dry in 5() or 100 pound bags and mixed with
water to form a solution. The mixture is then injected into the system by a small
pump.
-4-
-------
A schematic diagram of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recommended is as follows:
• Ground level improvements to the existing well which will accommodate the
installation of a pump.
• One 60 GPM submersible pump including electrical controls.
• One concrete valve pit constructed at the intersection of the deep and
shallow well discharge lines. The pit should contain meters and valves
on both lines.
• One 2000 gallon ground level pressurized chlorine contact tank.
• One gas chlorinator.
• One polyphosphate mixing and feed systaii.
• One equipment building.
COST
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the facilities were constructed and became operational during the 1980 calendar
year. By utilizing current data, the estimated annual cost increase is placed in
a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
The construction cost of the above-described facilities including engineering and
project contingency expenses has been estimated at $28,000. Annual costs are
summarized below.
—5—
-------
/
EXISTING
EQUIPMENT ‘ -I
BUILDING
L
EXISTING
ELEVATED
TANK
—
PROPOSED
EQUIPMENT
BUILDING
PROPOSED PUMP a
GROUND LEVEL WELL
IMPROVE MENTS
SCHEMATIC DIAGRAM OF PROPOSED
WATER SUPPLY ADDITIONS
AT
/
I
I PROPOSED
CONTACT TANK
I
/
/
I EXISTING
I SHALLOW
WELL
— 1
——-J
r 1 .EXISTING DEEP WELL
FIGURE 1
TOWN OF JAMESTOWN
-------
• Debt Service on a 30-Year Loan at 12% $3,476
• Operations and Maintenance 54
Total Estimated Annual Cost Increase $3,530
Assuming a uniform amortization of the estimated annual cost increase over the
entire consumer population, each consumer would be required to pay an additional
$39.22 per year. It should be noted that the above listed costs are premised
on the existing shallow well being satisfactory for use. Should a new well be
required, the annual per consumer cost increase will rise from $39.22 to $59.87 .
IMPLEFIENTATION
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of the proposed water system addition can be
accomplished within 24 months of completion of required referendums, rate
structure studies, funding procurement, etc.
OPERATOR REQUIREMENTS
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
-6-
-------
RE FERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study
for the Town of Jamestown, Berkeley County°, March 16, 1978.
2 Personal Comunication, Mayor Clark, Town of Jamestown, February 18, 1980.
-7-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
KIfIGSTREE
WILLIAMSBURG COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOL’TH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Supply 2
FLUORIDE REDUCTION
Alternative No. 1: Well Isolation
Method 3
Cost 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Blending
Method 5
Cost 6
Implementation 7
Operator Requirements 7
Sumary 7
REFERENCES 8
-------
I NTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). :nvestigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC OHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigatve effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Kingstree. In addition to addressing
the conceptual solution from a technical standpoint, planning—level cost esti-
mates are also presented. It should be noted that all capital costs are pre-
sented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING SUPPLY
The existing supply consists of four deep wells with a combined capacity of
1750 GPM. 1 Of the four, only the Highway 377 well produces water with a
fluoride concentration in excess of the legal limit. Said well has a rated
capacity of 500 GPM and was constructed in 1978 at an approximate cost of
$200,000.
The Highway 377 well presently pumps directly
that is supplied by all four operating wells.
single 12” main at the southeastern extremity
ride attenuation is accomplished by in-system
other wells.
into a common distribution system
Due to its location along a
of the system, little or no fluo-
blending with the product from the
-2—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Highway 377 well. Both alternatives were subsequently evaluated
to determine the most practical and least expensive method of effecting a solu-
tion to the fluoride problem. The ensuing paragraphs of this report document
the results of the evaluations and rank the alternatives in their order of desir-
ability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning—level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars. it is recqmended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: WELL ISOLATION
Method
The Highway 377 well is located in close proximity to five major consumers that
are exempt from the fluoride limitation. 2 Accordingly, this alternative calls
for the construction of a separate distribution main and elevated tank which will
serve the exempt users exclusively. The proposed mini-system would be supplied
-3-
-------
BASE MAP PREPARED BY
WACCAMAW REGIONAL PLANNING
AND DEVELOPMENT COUNCIL
FIGURE 1
LOCATION MAP OF PROPOSED
1INI—SySTEr1
AT KINGSTREE, SOUTH CAROLINA
/
/
,
-------
by the Highway 377 well, and would be isolated from the main system by appropri-
ate valves. The general location of the proposed mini—system is shown by
Figure No. 1.
The daily water use for the exempt facilities was estimated from information
provided by the Town and/or the respective user. Said usage is tabulated below:
• Warsaw Manufacturing 2,000 GPD
• Kingstree Manufacturing 285,000 GPO
• Williamsburg Technical College 50,000 GPO
• Kingstree Senior High School 20,000 GPO
• Williamsburg County Hospital 31,000 GPO
Total 388,000 GPO
Utilizing a 16-hour operating period for the Highway 377 well, total production
will be 480,000 GPD. That amount exceeds the estimated mini-system demand by
92,000 GPO (approximately 24%). Recognizing that the proposed water main will
parallel the Town’s existing system, it was assumed that fire flows would be
provided by the existing system. Consequently, fire flows were not included in
the following computation of storage requirements.
• Criteria: Provide average daily demand during any given 12-hour period.
• Well Capacity
(12 hr)(60 min)(500 GPM) = 360,000 gallons
• Storage Capacity
388,000 gallons - 360,000 gallons = 28,000 gallons
Use 50,000 gallons
The mini—system storage tank should consist of the elevated type with an overflow
elevation equal to that of the existing tanks presently maintaining pressure on
-4-.
-------
the Town’s distribution system. Tank piping should include an emergency fill
line connected to the main system via a check valve.
Cost
The estimated construction cost of the mini-system including engineering and
project contingency expenses has been estimated at $230,000. Annual debt service
expense on that amount calculated at 12% for 30 years is $28,552. Total system
operating costs would remain the same.
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract
negotiation and award, and construction of this alternative can be accomplished
within 30 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
ALTERNATIVE NO. 2: BLENDING
Method
Fluoride reduction in the Highway 377 well can be achieved by drilling a series of
shallow wells and blending their yield with that of the deep well. Assuming a
fluoride concentration of 0.1 mg/l in the proposed shallow wells, a shallow/deep
mix of 285 GPM/500 GPM will result in a blend having a fluoride concentration of
1.4 mg/i.
Lacking accurate data on the quantity or quality of shallow ground water available
in the Kingstree area, quantity was conservatively estimated at 50 6PM per well,
—5-
-------
x
,
/
I
\
\
— _-.c_ _
/
\ /
\ / N
FIGURE 2
SCHEMATIC DIAGRAM OF
PROPOSED WATER SUPPLY ADDITIONS
AT
//
5.5 ACRE WELL FIELD
/
I
/
6’ FENCE
/
/
/
50 GPM SHALLOW WELL
/
/
N
/
10 HIGHWAY 377 WELL
\
/\
10,000 GALLON
PRESSURE CONTACT
TANK
a
CHLORI NATOR
BUILDING
KINGSTREE, SOUTH CAROLINA
-------
requiring construction of six wells. Iron content was one aspect of quality that
was considered, disinfection was the other.
Sufficient iron to cause aesthetic problems, such as staining of plumbing fix-
tures, should be expected in the proposed shallow wells. Uith the favorable ratio
of deep/shallow welt water that will be utilized in this system, it was assumed
that the iron could be sequestered and then diluted sufficiently to preclude the oc-
currence of iron related nuisance problems. Feeding a solution of polyphosphates
(chemical) to the shallow wells will provide an economical means of controlling
red water. The chemical is purchased dry in 50 or 100 pound bags and mixed with
water to form a solution. The mixture is then injected into the system by a
small pump.
Shallow wells are generally more susceptible to bacterial contamination than are
deep wells. Consequently, chlorination should be effected with a gas machine.
The chlorinated water should subsequently be detained in a pressure contact tank
for 30 minutes prior to being blended with the deep well water.
A schematic drawing of the proposed water supply additions is presented in
Figure 2.
Cost
The estimated construction cost of Alternative No. 2 including engineering and
project contingency expenses has been estimated at $250,000. Annual debt service
expense on that amount calculated at 12% for 30 years is $31,035. Total system
operating costs would increase by approximately $500 per year due to the poly—
phosphate addition bringing the total annual increase to $31,535 .
-6-
-------
Implementation
Design, securing permits and approvals, solicitation of proposals, contract
negotiation and award, and construction of this alternative can be accomplished
within 24 months of completion of required referendums, rate structure studies,
funding procurement, etc.
QperatorReg i rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
SUI1MAR V
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
TOWN OF KINGSTREE
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Well Iso—
lation
No. 2: Blending
500
785
$28,552
$31,035
—0-
$500
$15.86
$17.52
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate 3 $11.10
• Estimated monthly increase 1.32
Adjusted Monthly Water Rate $12.42/consumer
—7—
-------
REFERENCES
1 Personal communication, Mike Tisdale, Town of Kingstree, March 18, 1980.
2 Personal communication, Fred Soland, South Carolina Department of Health and
Environmental Control, April 1, 1980.
3 South Carolina Department of Health and Environmental Control, ‘ 1 Staff Study
for the Town of Kingstree, Williamsburg County,” undated.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE TOWN OF LANE
WILLIAMSBURG COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION • 1
BACKGROUND
Consumers . . . 2
Water Supply Requirements
Current Demand 2
Projected Demand 2
Current and Projected Supply Requirements 3
Existing Supply 3
FLUORIDE REDUCTION
Method 4
Cost 6
Implementation 6
Operator Requirements 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC OHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Lane. In addition to addres-
sing the conceptual solution from a technical standpoint, planning—level cost
estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—l —
-------
BACKGROUND
CONSUMERS
The water system serving the Town of Lane provided water to 135 consumers,
approximately 500 people, as of February, 1978.1
Williamsburg County is expected to experience continued industrial growth during
the forseeable future. As a consequence of that growth, the consumer popula-
tion of the Lane water system is expected to grow. In lieu of actual planning
data which is not readily available, an annual growth rate of 5% will be
assumed in the ensuing sections of this report.
WATER SUPPLY REQUIREMENTS
Current Demand
The average daily water usage for calendar 1979 was 22,000 gallons. 2 That trans-
lates to an average of 165 GPD/connection. Maximum average daily demand was
considered to be approximately 180% of average daily usage. 3 Accordingly, the
current water demand placed on the system has been established as follows:
• Average Daily Demand 22,000 Gallons
• Maximum Daily Demand 39,600 Gallons
Projected Demand
Utilizing the previously assumed 5% annual growth rate in consumer population,
projected water demand has been estimated and is presented in the following
table.
-2-
-------
TOWN OF LANE
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
1995
2000
22,000
28,000
36,000
46,000
58,000
39,600
50,400
64,800
82,800
104,400
Current and Projected Supply Requirements
The below listed supply requirements were calculated utilizing a regulatory
design criterion requiring that the well or wells be capable of meeting the
maximum daily demand in a 16-hour operating period.
• 1980 - 41 GP!-1
a 1985 — 53 GPII
• 1990 - 68 GPM
• 1995 - 86 GPfl
• 2000 - 109 GPM
EXISTING SUPPLY
The existing water supply consists of one deep well having a rated capacity of
100 GPM. Based upon the present requirement of 41 GPM, the existing production
capability is adequate. It is noted, however, that water produced by the exist-
ing well contains 2.0 mg/l fluorde which exceeds the limit of 1.6 mg/i estab-
lished by law.
-3-
-------
FLUORIDE REDUCTION
METHOD
Based upon available information, the most practical and least expensive
method of effecting a fluoride reduction in the town’s water supply is to
drill a shallow well and blend its yield with that of the existing deep well.
Assuming a fluoride concentration of 0.1 mg/I in the proposed shallow well, a
shallow/deep mix of 45 GPFI/lOO GPM will result in a blend having a fluoride
concentration of 1.4 mg/i.
With the construction and operation of a shallow well, two aspects of water
quality that were of little or no concern before will require consideration.
One is disinfection, the other is iron content.
Disinfection should be effected in the blended supply with a gas chlorinator.
The new chlorinator should be equipped with a device designed to automatically
alternate from an empty gas bottle to a full one. The gas system requires
that the operator exercise greater care in handling the chlorine, but the
system itself is highly reliable and requires very little maintenance. It
is also recommended that the chlorinated water be detained in a pressure con-
tact tank for a minimum of 30 minutes before being discharged to the distribution
system. The existing water mains are capable of conveying water from the well
to the taps of several consumers almost immediately. Should a problem exist,
the short contact time presently possible would be inadequate for disinfection
to take place.
-4..
-------
Sufficient iron to cause aesthetic problems, such as staining of plumbing
fixtures, should be expected in the proposed shallow well. With the favorable
ratio of deep/shallow well water that will be utilized in this system, it was
assumed that the iron could be sequestered and then diluted sufficiently to
preclude the occurrence of iroc related nuisance problems. Feeding a solution
of polyphosphates (chemical) to the shallow well will provide an economical
means of controlling red water. The chemical is purchased dry in 50 or 100
pound bags and mixed with water to form a solution. The mixture is then
injected into the system by a small pump. It is possible that the existing
hypochiorination equipment can be rebuilt and used.
A schematic drawing of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recommended is as follows:
• One 45 GPM shallow well approximately 100 feet deep. The well should
be equipped with a vertical turbine pump set up to operate simultane-
ously with the deep well pump.
• One concrete valve pit constructed at the intersection of the deep and
shallow well discharge lines. The pit should contain meters and valves
on both supply lines and should also serve as an injection point for
the chlorine solution.
• One 5,000 gallon ground level pressurized chlorine contact tank.
• A pump house addition to accommodate the installation of a gas chlorinator.
The above-described facilities will bring the Lane water supply into compliance
with the fluoride standard. It will also increase the total system capacity to
145 GPM which should satisfy community requirements beyond the projection for
year 2000.
-5-
-------
‘I
I ’
PROPOSED SHALL W
=
—--J II
p
II
-------J
PROPOSED 5000 /
GAL. CONTACT TANK
Well
House J
PROPOSED CH LORI N /
ROOM ADDITION
Figure 1
SCHEMATIC DIAGRAM OF PROPOSED
WATER SUPPLY ADDITIONS
AT
(
It
It
PROPOSED ii PROPOSED
CONCRETE VALVE II CHLORINE
EXISTING
ELEVATED
TANK
PIT
)
x
TOWN OF LANE
-------
COST
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the facilities were constructed and became operational during the 1980 calendar
year. By utilizjng current data, the estimated annual cost increase is placed
in a proper perspective with the community’s present fiscal position. Recogniz-
ing that the cost data is presented in 1980 dollars, it is recommended that
initial planning of any alternative include a reevaluation of capital and operat-
ing costs with respect to anticipated construction schedules.
The construction cost of the proposed facilities including engineering and project
contingency expenses has been estimated at $60,000. Annual costs are summarized
bel ow.
• Debt Service on a 30-Year Loan at 12% $7,448
• Operations and rlaintenance 102
Total Estimated Annual Cost Increase $7,550
• Annual Cost Increase per Consumer $55.93
Construction of the facilities described in this report would result in the
following water rate increase.
• Existing monthly rate 1 $10.98
• Estimated monthly increase 4.66
Adjusted Monthly Water Rate $15.64/consumer
IMPLEMENTATION
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of the above-described facilities can be
—6—
-------
accomplished within 24 months of completion of required referendums, rate struc-
ture studies, funding procurement, etc.
OPERATOR REQUIREMENTS
Operator requirements for this system will not change as a consequence of fluo-
ride reduction in the water supply.
-7-
-------
REFERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study
for the Town of Lane, Williamsburg County”, February 27, 1978.
2 Personal Communication, Lois Martin, Town of Lane, February 4, 1980.
3 clarlc, J. W., et al., Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE TOWN OF LITTLE RIVER
HURRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COIIPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions 2
Future Conditions 3
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method 4
Cost Estimate with Iron Sequestering 6
Cost Estimate with Iron Removal 6
Implementation 6
Operator Requirements 7
Alternative No. 2; Purchase “later From GSWSA
Method 7
Cost Estimate 7
Implementation 8
Operator Requirements 8
Alternative No. 3: Treat Existing Wells
Method 8
Cost Estimate 9
Implementation 9
Operator Requirements 9
Sunrary . 9
REFEREI ICES 11
APPEUDI CES
Fluoride Treatment
Blending Graph
-------
INTRODUCTION
Beginning on June 24 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Uater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
in January, 1930, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Little River. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Little River water system presently has three wells in service. Accord-
ing to the system operator, Mr. Baldwin, all three are within 2500 to 3000
feet of each other. Well #1 is presently pumped at approximately 125 gallons
per minute (GPH), is relatively deep, has a fluoride concentration of approxi—
1
mately 2.7 mg/i and an iron concentration of 0.1 mg/i. Well #2 is pumped at
approximately 75 GPF4, taps shallower water zones than Well #1, has a fluoride
concentration of approximately 2.5 mg/i, and an iron concentration of approxi—
2
mately 0.8 mg/i. Well #2 is pumped directly to Weli #1 where the flows are
mixed, chlorinated, and piped into a 10,000 gallon pressure tank which is
connected to the distribution system. Well #3 serves the Bay Tree Condominium
and Golf Course system and has recently been connected to the Little River
system. ts pumping rate is approximately 200 GPI1, its screen is set
from 460 feet to 500 feet deep, fluoride and iron concentrations are reported
3
to be approximately 5.0 mg/i and 0.1 mg/i , respectively. The Little River
system has a 75,000 gallon elevated tank in Town and a 125,000 gallon elevated
tank at the Bay Tree well which should provide adequate peak day storage.
The Little River system presently serves
connections, a school, a golf club house
and various small commercial users. The
pleted system is estimated to be 100,000
demand is estimated by Waccamaw Regional
(WRPDC) to be approximately 0.12 million
day, approximately 0.16 MGD.
approximately 275 residental service
and pro shop, one industrial user,
average water demand of the new corn-
GPD. 5 The summer average water
Planning and Development Council
gallons per day (MGD) and the peak
—2—
-------
FUTURE CONDITIONS
WRPDC has estimated the future average summer water demands to be 0.24
MGD in 1990 and 0.35 MGD in the year 2000. Assuming the peak day factor
remains fairly constant, the peak day flows would be 0.32 TIGD in 1990 and
O 47 in the year 2000.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Meth ad
The alternative would involve the drilling of new wells to replace or blend with
the two existing high fluoride wells that have an acceptable iron concentration.
This alternative is heavily dependent upon the quantity and quality of shallow
ground water available, both of which are unknown. Therefore, for this to be a
viable solution, test and water zone sampling wells must be drilled near each
existing well to be used and sufficient, satisfactory water located to replace
or blend with the existing well water.
-4-
-------
Assuming that the shallow ground water will have a fluoride concentration of
0.2 mg/i or less, the blend ratio graph in the Appendix can be used to determine
the required quantity of shallow well water needed to blend with existing high
fluoride well water. The following table gives the amount of shallow well water
required for an acceptable fluoride blend and the maximum shallow well iron con-
centration to achieve a 1.0 mg/i iron blend. The 1.0 mg/i iron concentration is
somewhat arbitrary since the critical factor for this alternative to be a low
cost solution is that the iron in the blended water must either be less than
0.3 mg/i, which appears unlikely, or be suitable for sequestering to achieve an
acceptable water. To allow a safety factor, a 1.4 mg/i fluoride concentration
has been used as the acceptable concentration.
TOWN OF LITTLE RIVER
BLENDING DATA
Existing Wells
Proposed Wells
Well
Fluoride
(mg/i)
Iron
(mg/i)
Reduced
Capacity
(Gal/Mm)
Capacity
(Gal/Mm)
Iron
(mg/i)
#1
#2
#3
2.7
2.5
5.0
0.1
0.8
0.1
125
75
200
134
68
600
1.84
1.22
1.30
Since Ie11 #3 requires considerably more water for blending than is needed
for the entire water system in the future, blending would only be practical
if a much smaller pump is installed in this well. However, if blending is
achieved with Well #1 alone, the yield would be 259 GPM. Therefore, for this
alternative, the selected design capacity is 259 GPM. Based on discussions with
representatives of the USGS and South Carolina Water Resources Commission ( IRC),
it will be assumed that one test and sampling well, followed by two production
— 5-.
-------
wells, will be needed to achieve the 134 GPM required for blending. It will
be assumed that an iron sequestering unit will be needed at the existing well
site and that one blending well will be piped to the existing well site. To
indicate the impact of excessively high iron content in the new wells, the cost
of iron removal treatment has also been estimated. However, it is beyond the
scope of this study to predict whether or not iron removal treatment would be
requi red.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$110,000
$13,657
$ 1,000
$14,657
Cost Estimate with Iron Removal
O Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$250,000
$31,038
$15,728
$ 46,766
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendum, rate structure studies,
funding procurement, etc. It is estimated that the time would increase to 42
months if iron removal treatment is required.
-5-
-------
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative. However, if iron removal treatment is necessary, it is
anticipated that one additional water system operator may be required.
ALTERNATIVE NO. 2: PURCHASE WATER FROM GSWSA
Method
This solution would involve the purchase of water from Grand Strand Water and
Sewer Authority’s (GSWSA) Wampee system. This system is presently connected to
the Little River system and a master water meter is included at the connection.
This solution is reported to be unacceptable to the Little River Water Company
and, therefore, has the lowest rating of the alternatives. The Wampee well,
which is reported to pump 300 GPM, is estimated to be adequate for approximately
five years, if it were to serve both the Wampee and Little River service areas.
Cost Estimate
To the writer’s knowledge, no capital cost would be required to implement this
solution, at least for the first few years. Beyond that time, some rate increase
might be necessary to pay for a new well. This should be considered when compar-
ing the costs of the various alternatives.
4
Based on communication with GSWSA, the rate charged for water from the Wampee
system might range from $0.50 to $0.65 per 1000 gallons. The estimated added
annual operation cost using the $0.65 per 1000 gallon rate and deleting the cost
of pumping water from the existing wells would be $21,377 .
-7-
-------
Implementation
It has been estimated that the time required to achieve an acceptable agreement
between Little River and GSWSA concerning the method, rate, etc., of purchasing
water might take from 6 to 12 months.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
ALTERNATIVE NO. 3: TREAT EXISTING IELLS
Method
This solution would involve the treatment of well water from Wells #1 and #3 to
reduce the fluoride concentration. Well #2 would not be used since it has a high
iron concentration. The combined yield of Wells #1 and #3 would be 325 GPM or
0.468 which is just slightly less than the estimated peak day water demand for
the year 2000. Because Wells #1 and #3 are not far apart, it will be assumed that
the treatment system will be at one site with piping connections to the other
well.
The treatment process which appears to be the least expensive to reduce the fluo-
ride concentration is the activated alumina process. This process would involve
treatment of a portion of the flow from the wells and the blending of the bypassed
portion with the defluoridated water. Uhen the treatment capacity is exhausted,
the unit must be regenerated and the backwash discharged to the Town’s proposed
sanitary sewer system. For a description of the activated alumina process, see
the Appendix entitled “Fl uori de Treatment 11 .
-8-
-------
Cost Estimate
• Capital cost estimate for project design and construction $331,000
• Annual added debt service assuming 12% loan for 30 years $ 41,090
• Annual added operation cost using 1979 water use $ 26,000
• Total estimated added annual cost $ 67,090
Impl ementati on
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Regu I rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state ii-
cerise system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
-9—
-------
LITTLE RIVER
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
sequestering)
No. 2: Purchase
No. 3: Treatment
259
N/A
325
$13,657
-0—
$41,090
$1,000
$21,377
$26,000
$ 50.54
$ 73.71
$231.34
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water
rate increase.
• Existing nonthly rate 6
• Estimated niorithly increase ______
Adjusted monthly water rate
$14.50
4.21
$18.71/consumer
-10-j
-------
REFERENCES
1 DHEC Water Analysis Report, Little River, Sample #P-1599 , dated March 13, 1980.
2 DHEC Water Analysis Report, Little River, Sample #P-1601, dated March 13, 1980.
3 DHEC tiater Analysis Report, Little River, Sample #P-1600 , dated March 13, 1980.
4 Telephone communication with Bob Barker, Director of GSWSA, on April 9, 1980.
5 Telephone communication with Steve Hutchinson of Leon Campbell and Associates,
Engineers for Little River, on Iiarch 20, 1980.
6 DHEC Staff Study on Fluoride completed in 1978.
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE TOtflLl OF LORIS
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BAC KGROUND
Existing Conditions 2
Future Conditions . . . . . . 3
FLUORIDE REDUCTION
Alternative No. 1: Blend Existing Well Water
Method 4
Cost Estimate 6
Implementation 6
Operator Requirements 6
Alternative No. 2: Iron Removal Treatment
Method 6
Cost Estimate 7
Implementation 7
Operator Requirements 7
Alternative No. 3: Fluoride Removal Treatment
Method 8
Cost Estimate 8
Implementation 8
Operator Requirements 9
Summary 9
REFERENCES 11
APPENDIX
Fl uori de Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DREC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Loris. In addition to addres-
sing the conceptual solution from a technical standpoint, planning—level cost
estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Loris water system presently has five wells, with the largest (Well #2) being
the only one normally in service. 1 The other four wells have iron concentrations
which are generally from three to seventeen times the maximum recommended in the
Secondary Drinking Water Standard, and therefore are only used as backup wells
during a fire or other water shortage emergency. lIeu #2 is the only well known
to have a high fluoride concentration. The approximate pumping rates and fluoride
and iron concentrations of the wells are listed in the following table.
THE TOWN OF LORIS
EXISTING hELL DATA
Well
Capacity
(Gal/ Ilin)
Fluoride
(mg/i)
Iron
(mg/i)
Hardness
(mg/i)
#1 Walnut St.
#2 Spring St.
#3 Liberty St.
#4 Caroiina Furn.
#5 Carolina Furn.
150
400
300
300
50
1.3
3.8
0.3
0.2
1.30
0.01
(High)
1.00
5.00
36
16
150
150
The Town has a 300,000 gallon and a 75,000 gallon elevated tank which are used for
water storage. These tanks provide more than one day’s storage of water at current
water use rates which is quite adequate to meet their storage needs.
During calendar 1979, the Town used approximately 250,000 GPO on the average and
served approximately 870 customers. 5 However, increased consumption by a local
5
industry has recently boosted the daily average to 300,000 GPD.
—2—
-------
FUTURE CONDITIONS
The Town has experienced limited growth for several years. Waccamaw Regional
Planning and Development Council (WRPDC) has estimated that water supply needs
in Loris would increase from its present 300,000 GPD to 400,000 GPD by 1990 and
to 500,000 GPD by the year 2000.
URPDC estimated that the current maximum day water demand for Loris is approxi-
mately 400,000 GPD. This would be a 1.33 peak day factor which appears to be
realistic. In terms of pumping capacity, the present estimated peak day water
demand would require 16 hours of pumping at 416 GPM.
The alternatives evaluated in the ensuing pages of this study will be predicated
on maintaining the existing supply capacity of 400 GPM.
—3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated ccnsumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is present in 1980 dollars, it is reco iiiended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: BLEND EXISTING hELL WATER
Method
This alternative would involve the piping of Well #2, the high fluoride well, to
Well #4, the replacement of Well #2 pump with a smaller pump to achieve an accep-
table blend, and the addition of an iron sequestering unit at the Well #4 blending
point. The best connection piping route would need to be selected after a careful
study of all field conditions. However, for this report it will be assumed that
6” piping would be installed from Well #2 north along Spring Street to Church
-4-
-------
Street, then east along Church Street to the railroad, then south along Meeting
Street to Holly Street, then east along Holly Street crossing under the railroad
to Broad Street, then south along Broad Street to Walnut Street, then east along
Walnut Street to the site of tlell #4. That route would be approximately 6,900
feet in length.
The existing pump in the #2 well should be replaced with a 140 GPM unit. That
flow would be mixed with the 300 GPM from Well #4 to produce a blended water
having a fluoride concentration of approximately 1.4 mg/i. That concentration
should allow sufficient safety factor to stay within the 1.6 mg/i limit estab-
lished by law.
Blending the #2 well yield with that of Well #4 would result in an iron concentra-
tion of approximately 0.7 mg/i, which is 0.4 mg/i above the accepted aesthetic
limit.• In addition, the hardness of the combined supply would be approximately
107 mg/i as CaCO 3 , which would cause some laundering problems and promote scale
build-up in water heaters.
The iron problem may be overcome to a degree by sequestering (keeping it in solu-
tion) with a chemical solution addition of sodium hexametaphosphate. However, the
water must be tested to determine whether or not the iron content is amenable to
sequestering.
Cost Estimate
• Capital cost estimate for project design and construction $100,000
• Annual added debt service assuming 12% loan for 30 years $12,415
• Annual added operation cost using current estimated water use $ 3,300
• Total estimated added annual cost $ 15,715
-5-
-------
Implementation
It has been estimated that design, securing of pernits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: IRON REMOVAL TREATMENT
1ethod
This alternative would involve iron removal treatment of water from two existing
wells which have low fluoride but high iron concentrations. The sources selected
for the purposes of this study are Wells #1 and #4.
The project would include installing connection piping from Well #1, east along
Walnut Street, crossing the railroad and Broad Street, and into Well #4 site, the
tentatively selected treatment Diant site. This connecting route would be approx-
imately 2,000 feet long.
The iron removal treatment system selected for cost estimation purposes was a
Ferrosand filtration system with continuous potassium permanganate regeneration.
Hardness treatment is not included as a part of this alternative. Utilizing
Wells #1 and #4, the treatment unit capacity would be 450 GP I.
Cost Estimate
• Capital cost estimate for project design and construction $400,000
• Annual added debt service assuming 12% loan for 30 years $ 49,660
-6-
-------
• Annual added operation cost using estimated current water use $19,500
• Total estimated added annual cost $69,160
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 30 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are expected to increase as a consequence of
implementing this alternative. It is anticipated that at least one additional
water system operator may be required. Therefore, an operator’s salary was esti-
mated and included in the estimated operating cost.
ALTERNATIVE NO. 3: FLUORIDE REMOVAL TREATMENT
Method
This solution would involve the treatment of the water from Well #2. The treat-
ment process which appears to be the least expensive to reduce the fluoride con-
centration is the activated alumina process. This process would involve treatment
of a portion of the flow from each well and the blending of the bypassed portion
with the defluoridated water. When the treatment capacity is exhausted, the unit
must be regenerated and the backwash discharged to the Town’s sanitary sewer sys-
tem. For a description of the activated alumina process, see the Appendix entitled
“Fluoride Treatment”.
Well #2 is the only well requiring no iron treatment but containing excessive fluo-
ride concentrations; accordingly, it will serve as the proposed source of supply
for this evaluation.
—7—
-------
Cost Estimate
• Capital cost estimate for project design and construction $405,000
O Annual added debt service assuming 12% loan for 30 years $ 50,277
O Annual added operation cost using estimated existing water use $ 40,500
• Total estimated added annual cost $ 90,777
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride renoval technology. The present state license
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination, in
order to obtain an “A” operating license. Approximately 120 hours of formal train-
ing should be adequate to upgrade operator skills to the level required by the
proposed treatment system. The actual cost to the community for this training is
anticipated to be approximately $3,000 plus travel and living expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
-8-
-------
LORIS
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Iron Treat-
ment
No. 3: Fluoride
Treatment
440
450
400
$12,415
$49,660
$50,277
$ 3,300
$19,500
$40,500
$18.06
$79.49
$104.34
Based upon the above listed infornation, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
3
• Existing monthly rate $9.75
o Estimated monthly increase 1.51
Adjusted Monthly tIater Rate $11.26/consumer
-9-
-------
REFERENCES
Meeting and discussion with Mr. Rodney Hardee, water superintendent, on January 30,
1980.
2 DHEC Water Analyses Reports for Loris, South Carolina
Sample Point: Well #1, Police Station, taken April 3, 1980.
Sample Point: Well #4, small well, taken April 3, 1980.
Sample Point: Well #5, large well, taken April 3, 1980.
3 DHEC Staff Study on Fluoride for Town of Loris, dated April 19, 1978.
4 Water Analysis by Froehling and Robertson, Inc. for Sydnor Hydrodynamics Inc., for
Town of Loris, (Well #2), dated August 16, 1973.
5 lelephone communication with Mr. Rodney Hardee, water superintendent, on April 23,
1980.
-l 0-
-------
FLUORIDE REDUCTION
I N
PUBLIC “lATER SUPPLY
OF
THE MIKE WILLIAMSON MOBILE HOME PARK
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPART 1ENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRIFIE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . . . . . . 1
BACKGROUND
Existing Conditions . . . . . . . . . . . . . . . . . . . . . . 2
Estimated Peak Water Demand.. . . . . . . . . . . . . . . . . 2
Water Storage Quantity Verification . 3
FLUORIDE REDUCTION
Alternative No. 1: Drill New Well
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 6
Alternative No. 2: Purchase Water from Conway
Method 6
Cost Estimate 7
Implementation 7
Operator Requirements 7
Summary 7
REFERENCES 9
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC OHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Mike Williamson Mobile Home Park.
In addition to addressing the conceptual solution from a technical standpoint,
planning-level cost estimates are also presented. It should be noted that all
capital costs are presented in 1980 dollars and that all operating expenses were
calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Mike Williamson Mobile Home Park water system is reported 1 to consist of what
was at one time three very small water systems, each with its own well. The sys-
tem has one 1,500 gallon and one 1,550 gallon pneumatic tank 2 for water storage.
2
The system’s water has a fluoride concentration of approximately 3.2 mg/i. The
system’s water use is not metered. There are 40 mobile home sites presently
1
being served.
Assuming an average water use of 200 GPD per mobile home, it is estimated that
the average daily water demand would be 8,000 GPD.
ESTWATED PEAK WATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 3 the water demand would be 14,400 GPD. With that demand, the
desirable minimum pumping rate would be 15 GPM, which would allow the estimated
peak day water demand to be pumped in 1€ hours. If Ameen’s method 4 for
predicting instantaneous water demand on the supply system is used, the estimated
demand would be 136 GPM. However, this estimate is based on each residence having
four persons who use a total of from 400 to 500 GPD. Since this system serves a
trailer park, DUEC has indicated that 80% of Ameen’s instantaneous demand can
be used as the estimated demand. Using this instantaneous water supply demand,
4
kieen’s method of checking pneumatic tank size indicates that a well capacity of
at least 71 GPM will be needed if the existing 3,050 gallons of pneumatic tankage
is all the water storage available. However, an additional 5,000 gallons of
pneumatic tank capacity would allow the use of a 15 GPM well, which is estimated
to be sufficient to meet the peak day demand.
-2—
-------
WATER STORAGE QUANTITY VERIFICATION
Given:
1. A residential connections is design condition.
2. Existing pressure tank sizes are 1500 and 1550 gallons.
3. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Arneen in his book entitled “Comunity Water Systems” on pages 50
through 55, except that instantaneous demand is reduced to 80% of Ameen’s
estimate.
Calculations:
1. 4’) residences x 3.4 fP 1/resd. x 0.8 = 108.8 GPM instantaneous demand.
2. Usable pressure tank volume = 3050 4 = 762.5 gallons.
3. Tank contribution for 20 minutes = 762.5 20 minutes = 38.1 GPM.
4. “linimurn new well size to meet instantaneous supply demand = 109 GPI - 38 GPI 1 =
71 GPII.
5. Minimum pneumatic tank capacity with 15 GPM well = (109 GPM — 15 GPM) x 20
minutes x 4 = 7,520 gallons
6. Additional pneumatic tank capacity needed = 7,520 gal. = 3,050 gal. =
4,470 gallons. Use 5,000 gallon tank.
—3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this coniiiunity. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
suits of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1983 planning—level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: PURCHASE WATER FROM CONWAY
Meth ad
This alternative would involve the installation of a master water meter and
approximately 150 yards of connection water main between the Mike Williamson Mobile
Home Park and a proposed extension of the Conway water system. Conway plans to
5
extend a water main along Highway 905 past this community by the end of 1981.
It should be noted that connection to the Conway system will not eliminate the high
fluoride problem until Conway corrects their own problem.
-4-
-------
Conway has advised that they presently charge $2,600 for a 3” water meter instal-
lation, which would probably be required for this mobile home park. The City’s
proposed water rates, which are likely to be in effect by the end of June, 1980,
are $5.00 minimum per dwelling per month for the first 2,000 gallons plus $0.75
per each 1,000 gallons used in addition to the first 2,000 gallons. 6 To this
rate, an increase of $0.64 per 1,000 gallons must be added to cover the minimum
cost which Conway is expected to incur in solving their fluoride problem.
Cost Estimate
• Capital cost estimate for connection installation $5,000
• Annual added debt service assuming 12% loan for 30 years $ 621
• Annual added water cost, less power cost, using estimated
water use $5,634
• Total estimated added annual cost $6,255
Implementation
It has been estimated that securing of approvals and a water service contract,
and construction of this alternative can be accomplished within 24 months of
the cor ip1etion of funding procurement, etc.
Operator Regui rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: DRILL NEW WELL
Method
This alternative would involve the drilling of a new well to replace or blend
with the existing high fluoride wells. Since it has been estimated that 15 GPM
-5—
-------
would be needed to meet the peak water demand with additional storage, a replace-
ment well appears to be a more practical solution than the operation of two wells.
It should be noted that this alternative is heavily dependent upon the quantity
and quality of shallow ground water available, both of which are unknown. There-
fore, for this to be a viable solution, a test and water zone sampling well must
be drilled and sufficient, satisfactory water located.
For cost estimating purposes, it will be assumed that a 15 GPM replacement well,
a 5,000 gallon pneumatic tank, and an iron sequestering unit is to be installed.
Cost Estimate
• Capital cost estimate for project design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added operation cost using estimated water use $ 100
• Total estimated added annual cost $ 5,687
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required rate structure studies, funding
procurement, etc., provided only iron sequestering is required. It is estimated
that the time would increase to 42 months if iron removal treatment is required.
Operator Regui rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
—6—
-------
SUMMARY
The alternatives which were evaluated during the course of this study are suma—
rized in the following table.
MIKE WILLIAMSON MOBILE HOME PARK
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPrI)
nnual Cost Data
Capital
Operating
Per Consumer
No. 1: Purchase
Water
No. 2: New Well
N/A
15
$ 621
$5,587
$5,634
$ 100
$156.38
$142.18
Based upon the above listed information, Alternative No. 2 is the least expensive
method of effecting a solution to the fluoride problem in this community. However,
purchasing water from the City of Conway would provide this community with a more
reliable municipal water supply. Accordingly, we recommend that Alternative No. 1
be implemented.
Presuming that the increased annual cost will be amortized uniformly over the
existing consumer population, the annual incremental increase was calculated to
be $156.38 per consumer ($13.03/month).
—7—
-------
REFERENCES
1eetinq and discussion with hike ‘Iilliarnson on February 5, 1980.
2 DHEC Staff Study on Fluoride, dated May 15, 1978.
3 Clark, J. I d, et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pennsylvania.
4 Ameen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical Proceed-
ings, Post Office Box 5041, Hiq i Point, North Carolina.
5 Telephone conversation with Fir. tlinfield, Director of Public Iorks for Conway,
South Carolina, on !1arch 7, 1080.
°Teleohone conversation with Mr. ‘iinfield, Director of Public Works for Conway,
South Carolina on April 14, 1980.
7 Letter from Fred H. So and of DHEC to J e Wilison of JESCO dated May 5, 1980.
-8-
-------
FLUORIDE REDUCTIO II
Ill
PUBLIC WATER SUPPLY
OF
TOWN OF MT. PLEASANT
CHARLESTON COUNTY, SOUTH CAROLINA
JULY, 1983
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Pag
INTRODUCTION 1
BPICKGROUND
Consumers 2
NATER SUPPLY REQUIREMENTS
Current Demand 3
Projected Demand 3
Current ar 1 d Projectev Supply Requirerents 4
EXISTING SlJrri.Y 4
rLU0RIDE P.ED JCTiO i
A1ternative Mo. 1: fll 1 ding
6
— ? 9
)ar 1
Plant L2 9
Cost 9
Implementation 10
Operator Requirements 10
Alternative No. 2: Treatment
Method 10
Cost 11
Implementation 11
Operator Requirements 11
Summary 1 1
REFERENCES 13
APPENOT X
Flouride Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tlater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
gi-arted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water su p1ies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Mt. Pleasant. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROJJIID
C0?ISUIIERS
The Town of Mt. Pleasant provided service to 5,200 consumers (approximately 14,000
people) as of January, 1980.
Population projections for the entire geographical area served by the Mt. Pleasant
water system were obtained from the Berkeley Charleston Dorchester Council of
Governments. Recognizing that Bulls Bay Rural Community Water District serves a
portion of that geogra7nical area and that scme residents do not have access to a
ub1ic water supply, tiC oopulation projections were not converted directly to water
der’iand. instead, they served as a basis for establishing growth factors ihich were
applied to th existing cun3unler inventory. Consumer projections determined in
accordance ;ith the above—described methodology are summarized in the following
tabi e.
TOUH OF MT. PLEASAUT
COI1SUMER POPULATIOII PROJECTIONS
Year
*Geographica l
Area Population
% Increase
flo. Consumers
1980
1985
1990
1995
20524
24036
26789
29454
-0-
17%
11%
10%
5200
6084
6753
7428
*Geographjcal area population includes people residing in the old section of town
plus those living in unincorporated areas lying east of the Cooper River.
-2-
-------
IJATER SUPPLY REQUIREMENTS
Current Demand
Daily water demand in the three service areas comprising the town’s water system
during calendar 1979 are listed in the following table. 2
TOWN OF MT. PLEASANT
AVERAGE DAILY WJ\TER DEMAND IN GALLONS
Month
Plant #1
Plant #2
Plant #3
System
January
February
March
April
flay
June
July
August
September
October
November
December
Average
524,929
439,321
453,635
Unknown
643,825
669,317
606,913
574,210
481,540
318,107
328,367
294,258
485,000
239,487
240,286
277,488
***282,633
282,181
228,836
379,065
439,548
358,497
384,451
422,231
442,677
335,000
308,842
336,343
271,700
***221,743
241,039
266,833
246,132
258,948
262,243
390,994
332,870
422,503
305,000
1 ,073,258
1,015,950
*1,102,823
1,167,045
1,164,986
1,232,110
**l,272,706
1,102,280
1,093,552
1,083,468
1,159,438
1,125,000
*Low month
**High month
***FIot included in averages
Maximum daily demand was considered to be approximately 180% of average daily usage. 3
Those maximums are as follows:
• Plant #1
• Plant #2
• Plant #3
• System
873,000 GPO
603,000 GPD
549,000 GPO
2,025,000 GPD
Projected Demand
Translating current system data to individual consumer demand, the average daily
usage per connection was placed at 216 gallon per day/consumer. Utilizing that
-3-
-------
value future water demand was calculated and is summarized in the following
table.
TOWN OF fIT. PLEASANT
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
1995
1,125,000
1,314,000
1,459,000
1,604,000
2,025,000
2,365,000
2,626,000
2,888,000
Current arid Projected pply Requi rements
The below listed suppìy requirenents were calcuiate utilizing a SI. DhEC design
cciterion req yiri that the well or wells be capable of meeting the niaximuni
djily demand in a 22-hour operating period.
980 - 2109 G ’M
1935 - 2’.53 GPII
1990 - 2735 3PM
e 1995 — 3008 GPfl
EXISTING SUPPLY
The Mt. Pleasant water supply consists of three separate plants all of which pump
into a common distribution system. Each of the three supplies consist of one
deep well and a series of shallow wells. The installed well capacity of each
plant is as follows:
Plant #1 (Simmons St.)
Deep tlell 900 GPM
Eleven Shallow lells 275 GPf1
-4—
-------
• Plant #2 (Mathis Ferry Road)
Deep Well 900 GPM
Twelve Shallow Wells 300 GPM
• Plant #3 (Snee Farm)
Deep Well 250 GPM
Eleven Shallow Wells 275 GPM
-5—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Town of Mt. Pleasant. Each alternative was subsequently evaluated
to determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
sults of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
?nd 1980 planning-level cost data. Consequently, the estir i ted consumer expense
reflects t p esent day situation. In other words, the assumDtio; :as made tnat
the alternative was constructed and became operational during the 1930 calendar
year. By ‘tii zing current data, comparison of the various alternatives is
placed in a proper perspective with the cc nunity’s present fiscal position.
R cc nizimj that the ccst data is presented in 1980 dollars, it is recor meric 1 s
at nt planning of any alternative include a reeva1u tion of capital a i
erating co5ts with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: BLENDING
Method
To achieve a blend of deep and shallow well water having a combined fluoride con-
tent of 1.4 mg/l, the deep/shallow blend ratio must be maintained at 1 GPI4/2.22
GPM. Utilizing the total combined shallow well capacity of 850 GPM, the deep
well production would be limited to 385 GPM. It should be noted that during a
-6—
-------
16-hour pumping day the resulting supply of 1235 GPM would be 42% deficient in
1980 and 50% deficient by 1985. The computation of those deficiencies was made
as follows:
• 1980
Required 2109 GPM
Available 1235 GPM
Deficiency 874 GPM
874 GPM = 42%
2109 GPM
• 1985
Required 2463 GPM
Available 1235 GPM
Deficiency 1228 GPM
J228GPM = 50%
2463 GPM
Consequently, this alternative will require the construction of additional shallow
wells. The initial phase will be sized to accommodate 1985 flow requirements.
Beyond that, nine shallow wells will have to be constructed for each 100 GPN
increase in deep well capacity that is utilized.
One other item noted during the study was that the Town’s booster pumping facili-
ties are operating at or near capacity. Due to the limited scope of this study,
an in-depth evaluation was not possible. However, the following cursory compu-
tations are presented for the information of the reader.
• Capacity Data
Plant #1 (measured capacity)
One Pump = 450 GPM
One Pump = 480 GPM
Combined Capacity = 650 GPM
Plant #2 (rated capacity)
Two pumps @ 500 GPM each
Assumed combined capacity = 650 GPM
—7—
-------
Plant #3 (rated capacity)
Two pumps @ 500 GPM each
Assumed combined capacity
• Available Capacity with One Pump
480+500+500 =
(1480 GPM)(24 hr)(60 min/hr) =
• 1980 Adequacy
Average Day
1,125,000 gal = 53%
2,131,200 gal (12
Maximum Day
2,025,000 a1 = 95
2,131,200 t1a
• 1935 ec;Lacy
, .‘eri ge Day
• ‘‘ ‘ r ,r r — —
•..)i’ ,L ’J Oai
• 131,20O gal
• - ‘ n )ay
.355, )00 qal =
..,13i,200 ça
= 650 GPM
1,480 GPM
2,131,200 GPD
Run Time
hrs, 43 mm)
Run Time
hrs 8 pith)
Run Time
‘14 hrs, 52 mm)
i1 Run Time
nadequate
Based upon visual inspections of the three water plant sites, the plants were
ranked according to the apparent availability of new shallow well sites. The site
selected as most suited to shallow well additions was Plant #3 (Snee Farm). The
second was Plant #2, and the third, or least desirable was Plant #1. Consequently,
the required 1985 capacity of 2463 GPM will be met by maximizing the use of deep
Well #3, maximizing the use of the shallow wells at Plant #1, and providing the
remaining capacity at Plant #2. The modifications and/or additions required to
achieve that end are described in the following paragraphs. One other item that
should be noted is that the following scenarios assume that the existing distri-
-8-
-------
auo ix noua loti
IN
PUBLIC WATER SUPPLY
OF
THE CITY OF CONWAY
W)RRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions . 2
Future Conditions 3
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
Method 4
Cost Estimates With Iron Sequestering 6
Cost Estimates with Iron Removal 6
Implementation . 6
Operator Requirements 7
Alternative No. 2: Treat Existing Wells
Method
Cost Estimate 7
Implementation 8
Operator Requirements 8
Alternative No. 3: Regional Water System
Method 8
Cost 9
Implementation 9
Operator Requirements 9
Summary.. g
REFERENCES 11
APPENDICES
Regional System
Fluoride Treatraent
Blending Graph
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of The City of Conway. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—l —
-------
BAC KG ROUND
EXISTING CONDITIONS
The Conway and Conway Rural water systems are both operated by the City of
Conway and presently have six and two wells, respectively, which are spread
throughout their service areas. All wells are rated at 500 gallons per minute
(GPM) and are reported by DHEC 2 to have fluoride concentrations in excess of
the 1.6 milligrams per liter (mg/I) limit set by EPA. The shallow ground
water from ground level down 100 to 200 feet in the area is generally reported
to have quite high iron concentrations, in the range of 2.0 to 3.0 mg/l, but
relatively low fluoride concentrations, generally in the neighborhood of 0.1 to
0.2 mg/i. 3 Below the iron laden water zones, the water is quite high in
fluoride, in the 3.5 to 5.0 mg/i range, but the concentration decreases with
depth until the salty zones are reached at a depth somewhere below 770 feet
below mean sea level (MSL). The fluoride concentration in the water zones
from 585 to 762 feet below MSL are reported by OHEC to have an average fluoride
concentration of 2.2 mg/i 2 and, by independent laboratory analyses, to have an
iron concentration of from 0.01 to 0.25 mg/i.
The City system has three 200,000 gallon elevated water tanks and the Conway
Rural system has one 200,000 gallon elevated water tank. As for sanitary
sewers which might be used for disposal of treatment wastewater presently
Wells #1 through #4 have sewers within a reasonable distance. Sewers are
planned for the areas near the Conway Rural wells and should be in service
within a couple of years.
The City water system had 3,584 connections 1 in 1979 which served a population
of approximately 10,000. The Conway Rural system had 346 connections 1 which
—2-
-------
served to a population of approximately 1,000. The average and peak day water
demands 1 for 1979 were 0.955 million gallons per day (MGD) and 1.125 MGD,
respectively for the City system, and 0.376 MGD and 0.476 MGD, respectively,
for the Conway Rural system.
FUTURE CONDITIONS
1
The City has estimated the average and peak day water demands for 1985 to be
1.8 MGD and 2.5 1GD, respectively, for the City system and 0.75 MGD and 1.0 MGD,
respectively, for the Conway Rural system. The Waccamaw Regional Planning and
Development Council (WRPDC) had estimated that the average day water demand would
be 2.0 MGD for 1990 and 2.5 MGD for the year 2000 for the combined City and Conway
Rural systems. Since the City has estimated a lar9er growth than WRPDC. the
writer has increased the WRPDC predictions and estimated that the average and peak
day water demands might be 3.0 FIGD and 4.0 MGD, respectively, for 1990 and 3.5
MGD and 4.66 MGD, respectively, for the year 2000.
The City also advised that one new 500 GPM well is being planned for installation
in 1980 for the City system, and also one new 500 GPM well for the Conway Rural
system was being planned. The City Drefers to have at least twice as much pump-
ing capacity as the peak day water demand.
-3-
-------
FLUORIDE REDUCTI ON
Preliminary investigative efforts identified several viable fluoride reduction
alternatives for this community. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desir-
ab i Ii ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Method
This alternative is heavily dependent upon the quantity and quality of shallow
ground water actually available, both of which are unknown. Therefore, for this
to be a viable solution, test and water zone sampling wells must be drilled near
each existing well to be used and sufficient, satisfactory water located to
-4-
-------
achieve an acceptable blend. The water located must have a relatively low fluo-
2
ride and iron concentration. Using the water analyses provided by DHEC and
assuming that the shallow water will have a fluoride concentration of 0.2 mg/i
or less, the blend ratio graph in the Appendix can be used to determine the re-
quired quantity of shallow well water needed to blend with the deep well water.
To choose a reasonable design flow for this solution, this alternative will in-
volve blending at six of the City’s eight deep wells to achieve 3000 GPM yield
of acceptable water. To allow a safety factor, a 1.4 mg/i fluoride concentration
will be used as the acceptable concentration. Wells #1, 2, 3, 4, 6 and Conway
Rural #2 will be used for this alternative since they have a lower fluoride con-
centration than the other two wells in the system. The following table gives
the amount of deep and shallow water required for an acceptable fluoride blend
and the shallow well iron concentration to give a 1.0 mg/i iron blend. The 1.0
mg/l iron concentration is somewhat arbitrary since the critical factor for this
alternative to be a low cost solution is that the iron in the blended water must
either be less than 0.3 mg/i, which appears unlikely, or be suitable for sequester-
ing to achieve an acceptable water.
CITY OF CONWAY
BLENDING REQUIREMENTS
Existing Well Data
Proposed Well Data
Well
Fluoride 2
(mg/i)
Iron’
(mg/i)
Reduced
Capacity
Capacity
Iron
(mg/i)
#1
#2
#3
#4
#6
R—112
2.2
2.1
2.3
2.1
2.2
3.0*
0.01*
0.25*
0.01*
0.01*
0.03*
0.06*
303 GPFI
318 GPM
289 GPM
318 GPM
303 GPM
215 GPM
197 GPFI
182 GPM
211 GPM
182 GPM
197 GPM
285 GPM
2.52
2.31
2.36
2.73
2.49
1.71
*Not from SC DHEC analysis.
—5—
-------
As can be seen by the table, this alternative is based on the assumption that the
existing deep well pumps will be replaced with smaller pumps to achieve the de-
sired blend. Also, it will be assumed that shallow wells will produce 75 GPM and
therefore, multiple wells and well lots with connecting piping will be required
to serve each deep well. With limited data on the shallow ground water, it appears
that iron sequestering would be marginally possible. However, costs have been
estimated on such a system for comparison purposes. This alternative assumed that
iron removal treatment will be required.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$1 ,090,000
$ 135,324
$ 13,310
$ 148,634
Cost Estimate with Iron Removal
o Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$2,340,000
$ 290,511
$ 22,789
$ 313,300
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 30 months of the completion of required referendum, rate structure studies,
funding procurements, etc., provided only iron sequestering is required. It is
estimated that the time would increase to 54 months if iron removal treatment is
requi red.
-6-
-------
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative, if iron sequestering is required. However,
if iron removal treatment is necessary, it is anticipated that an additional water
system operator may be required.
ALTERNATIVE NO. 2: TREAT EXISTING WELLS
Method
This solution would involve the treatment of existing well water to reduce the
fluoride concentration. To be consistent with the previous alternative, it will
be assumed that only six of the wells will be treated. Wells /1, 2, 3, 4 and
CR1 and CR2 would be the most likely candidates since they either have a sewer
nearby now or sewers are planned. Each well would have its own treatment unit.
The treatment process which appears to be the least expensive to reduce the fluo-
ride concentration is the activated alumina process. This process would involve
treatment of a portion of the flow from each well and the blending of the bypassed
portion with the defluoridated water. When the treatment capacity is exhausted,
the unit must be regenerated and the backwash discharged to a nearby sanitary
sewer. For a description of the activated alumina process, see the Appendix
entitled “Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $2,270,000
• Annual added debt service assuming l2 loan for 30 years $ 281,798
• Annual added operation cost using 1979 water use $ 207,000
• Total estimated added annual cost $ 488,798
-7-
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Req ui rements
The State of South Carolina requires a licensed A operator for those systems em-
ploying activated alumina fluoride removal technology. The present state license
system requires a high school education, four years experience as an operator in
a public water treatment plant, and the ability to pass a written examination,
in order to obtain an “A t ’ operating license. Approximately 120 hours of formal
training should be adequate to upgrade operator skills to the level required by
the proposed treatment system. The actual cost to the community for this train-
ing is anticipated to be approximately $3,000 plus travel and living expenses.
ALTERNATIVE NO. 3: REGIONAL WATER SYSTEM
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains convey the water
in a westerly direction as far as Conway, in a southerly direction as far as
Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
-8-
-------
See the Appendix entitled “Regional Water System” for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallons. At the current average daily demand of
1,331,000 gallons, the annual cost woul! be $1,433,154.
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
p ratorReq Iiremen ts
Operator requirements for this system are not expected to change as a consequence
of implementation of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
CONWAY AND CONWAY RURAL
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
treatment)
No. ‘2: Treatment
No. 3: Regional
3,000
3,000
2,778
$290,511
$281,798
$1,294,454
$ 22,789
$207,000
$138,700
$ 79.72
$124.38
$364.67
—9-
-------
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this comunity.
Construction of the primary alternative will result in the following water rate
increase.
4
• Existing monthly rate $7.55
• Estimated monthly increase 6.64
Adjusted monthly water rate $14.19/consumer
-10-
-------
REFERENCES
Data personally received from Mr. Winfield, Public Works Director of Conway,
at meeting held February 6, 1980.
4 DHEC Staff Study on Fluoride for Conway, dated May 4, 1978 and for Conway Rural,
dated May 8, 1978.
Water
Analysis
Reports
as follows:
City
Well
#1,
Sample
#P080,
dated
July
19,
1979, F =
2.2
mg/i
City
Well
#2,
Sample
#P081,
dated
July
19,
1979, F =
2.1
mg/i
City
Well
#3,
Sample
#P082,
dated
July
19,
1979, F =
2.3
mg/l
City
Well
#4,
Sample
#P083,
dated
July
19,
1979, F =
2.1
mg/i
City
Well
#5,
Sample
#P076,
dated
July
19,
1979, F =
2.5
mg/l
City
Well
#6,
Sample
#P077,
dated
July
19,
1979, F =
2.2
mg/i
Conway Rural #1
Conway Rural #7
3 Meeting and discussion with Al
South Carolina Water Resources
Zack of U.S. Geologic Survey and Larry West of
Commission, on February 5, 1980.
—11—
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
CRYSTAL LAKES MOBILE HOME PARK
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Pa _ g
I NTRODUCTION 1
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirement 2
Existing Suprly 2
FLUORIDE REDUCTION
Alternative No. 1: Water Purchase
Method 3
Cost 4
implementation 4
Operator Requirements 4
Alternative No. 2: Treatment
Method 5
Cost
Implementation 5
Operator Requirements 6
Sumary 6
REFERENCES 7
APPENDIX
Fluoride Treatment
-------
1
June 21, 1978 DHEC memorandum, it appears possible to find low fluoride water at
a shallower depth than the two existing Mierican Heritage wells. Shallow wells
at nearby Taylor Lumber Company, Inman and Associates, and Wesco Steel were re-
ported to have fluoride concentrations of less than 0.1 mg/i. Water samples
from the nearby Moose Lodge and Airport Skateland wells had 1.4 mg/i and 1.1 mg/i
of fluoride, respectively. The Moose Lodge well was reported to be 405 feet deep.
If blending of existing well water with that of a new well is proposed, the exist-
ing 45 GPM well would require 72 GPM of low fluoride (0.2 mg/i or less) water,
while the existing 28 GPM well would require only 12 GPM to achieve a safe, accep-
table blended fluoride concentration of 1.4 mg/i. Since a combined yield of 28
GPM and 12 GPM would be less than the 43.4 GPM needed for the peak day, a yield
of at least 15.4 GPM would actually be the predicted minimum desirable pumping
rate of a new well. Due to the uncertainty associated with the quality of
shallow ground water, it will be assumed for cost estimation purposes that iron
sequestering and chlorination equipment with an enclosure will be required with
the installation of a new well. Also, as discussed previously, a 7,500 gallon
pneumatic tank must be added to the system with a total well capacity of 43.4 GPM.
COST ESTIMATE
• Capital cost estimate for project design and construction $50,000
• Annual added debt service assuming 12% loan for 30 years $ 6,208
• Annual added operation cost using 1979 estimated water use $ 100
• Total estimated added annual cost $ 6,308
I tIPLEMENTAT ION
It has been estimated that design, securing of approvals, advertisement, contract
execution, and construction on this alternative can be accomplished within 24
months of the completion of required referendums, rate structure studies, funding
procurement, etc.
—5—
-------
OPERATOR REQUIREMENTS
Operator requirements for this system are not expected to change as a consequence
of implementation of this alternative.
SUMMARY
Based upon available information, the most practical and least expensive method
of solving the fluoride problem for the 1 erican Heritage Mobile Home Park appears
to be to construct the well project described above. Presuming that the increased
annual cost will be amortized uniformly over the existing customer population of
65, the annual incremental increase is calculated to be $97.05 per consumer
($8.09/month).
-6-
-------
REFERENCES
1 DHEC Memorandum, Subject: Mierican Heritage Mobile Home Park, Lexington
County; From: Fred H. Soland, Jr., P. E.; To: File; dated June 21, 1978.
2 Clark, J. W., et al. Water Supply and Pollution Central , paae 35, 1971,
International Textbook Company, Scranton, Pennsylvania.
3 Arneen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, North Carolina.
4 Letter from Fred H. Soland of DHEC to Joe Wilison of JESCO dated May 5, 1980.
—7-
-------
matic tank capacity would allow the use of a 43.4 GPM well, which is estimated
to be sufficient to meet the peak day demand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 165 residential connections assumed as design condition.
2. Combined yield of new and existing well is assumed to be 43.4 GPM.
3. Existing pressure tank size is 5,000 gallons.
4. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. I\meen in his book entitled “Community Water Systems” on Pages 50
through 55, except that instantaneous demand is reduced to 80% of Ameen’s
estimate.
Calculations:
1. 165 residences x 1.5. GPf 1/resd. x 0.8 = 199.2 instantaneous demand.
2. Usable pneumatic tank volume = 5,000 4 = 1 ,250 gallons.
3. Tank contribution for 20 minutes = 1,250 20 minutes = 62.5 GPM
4. Minimum new well size to meet instantaneous supply demand = 199.2 GPM —
43.4 GPM = 155.8 GPM.
5. Minimum pneumatic tank capacity with a 43.4 GPM well = (199.2 GPM — 43.4 GPM)
x 20 minutes x 4 = 12,464 gallons.
6. Additional pneumatic tank capacity needed = 12,464 gal. - 5,000 gal. =
7,464 gallons. Use 7,500 gallon tank.
-3-
-------
FLUORIDE REDUCTION
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the cornmunity s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative should include a reevaluation of capital
and operating costs with respect to anticipated construction schedules.
METHOD
The viable alternatives for this system appear to be quite limited. One possible
alternative would be to connect to the City of Cayce’s water system. However,
the end of the Cayce water system is approximately 1.8 miles from the American
Heritage Mobile Home Park. Utilizing an estimated construction cost of $6.00 per
foot for a 6” diameter PVC pipe installation, the cost would be over $57,000.
Other costs would include a possible $10,000 tap fee, a master meter installation,
drive and roadway repairs, highway borings, etc. Due to the high cost per resi-
dence, this possible alternative has been eliminated by the writer. Treatment
for fluoride reduction has also been eliminated for the same reason. It is, how-
ever, the system owner’s prerogative to investigate and select any alternative
that will bring this supply into compliance with the law.
The only viable alternative for this system appears to be the drilling of a new
well to tap a more acceptable water source. Based on information contained in a
-4-
-------
3.5 mg/i, it would take approximately 53 GPM of low (0.2 mg/i or less) fluoride
well water to blend with the existing 30 GPM well to achieve a safe, acceptable
blended fluoride concentration of approximately 1.4 mg/i. Since it has been
estimated that only 14 GPM will be needed to meet the peak day demand with addi-
tional storage, it is more practical to assume that a new well can be constructed
to meet the peak day water demand, rather than to achieve sufficient water to
blend with either existing well. Therefore, for cost estimating purposes, instal—
lation of a 14 GPM well with a 6,500 gallon pneumatic tank will be assumed.
Excessive iron, requiring iron removal treatment, r’iight be encountered. However,
it appears reasonable to assume that 14 GPM of relatively low iron, low fluoride
water can be located. Therefore, for cost estimating purposes, it will be
assumed that iron sequestering will be required.
COST ESTIMATE
O Capital cost estimate for project design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added operation cost using 1979 estimated water use $ 50
• Total estimated added annual cost $ 5,637
IMPLEMENTATION
It has been estimated that design, securing of approval, advertisement, contract
execution, and construction on this alternative can be accomplished within 24
months of the completion of required referendum, rate structure studies, funding
procurement, etc.
-5—
-------
OPERATOR REQUIREMENTS
Operator requirements for this system are not expected to change as a consequence
of implementation of this alternative.
SUMMARY
Based upon available information, the most practical and least expensive method
of solving the fluoride problem for the Central Mobile Home Village appears to be
to construct the well project described above. Presuming that the increased
annual cost will be amortized uniformly over the existing customer population,
the annual incremental increase is calculated to be $156.58 per consumer ($13.05!
month).
-6-
-------
REFERENCES
1 DHEC Memorandum, Subject: Central Mobile Home Village, Horry County:
From: Fred H. Soland, Jr., P. E.; to: File; dated August 11, 1978.
2 DHEC Analysis Report, Station Code 626012, Laboratory Sample No. P071660070,
FDW-51, dated July 13, 1976.
3 Clark, J. W., et al. ttater Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, PennsyTvania.
4 Ameen, Joseph S., Coniiiunity Water Systems , pages 50-55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, North Carolina.
5 Letter from Fred H. Soland of DHEC to Joe Willson of JESCO dated May 5, 1980.
-7-
-------
bution system has sufficient hydraulic capacity to accommodate the required shift
in the physical location of production capacity.
Plant #3 has a deep well capacity of 250 GPM. The desired blend will require that
the shallow well capacity be increased from 275 GPM to 550 GPM. That increase
will necessitate the construction of eleven additional shallow wells. The total
combined capacity of the expanded supply will be 800 GPM, approximately 32% of
the required total.
Plant #1 has a combined shallow well yield of 275 GPM. The desired blend will
allow the use of 125 GPM of deep well water. Based upon available information,
it appears that the artesian flow from the deep well will provide the required
amount of water. The existing electric operated valve will start and stop the
flow simultaneous with the operating of the shallow wells, the deep well discharge
valve can be utilized to accomplish any required throttling. The resulting capac-
ity of this facility will be reduced to 400 GPM, approximately 16% of the required
total.
Plant #2 will be utilized to provide the remaining 1263 GPM necessary to meet the
maximum daily demand in the year 1985 with a 16-hour pumping day. The desired
blend at this facility will require an increase in shallow well capacity from 300
GPM to 900 GPM. Said increase can be accomplished by drilling 24 new wells. The
deep well capacity that can be utilized is 400 GPM. The existing pump should be
replaced with a smaller unit or modified by removing one or more of the existing
bowl assemblies to facilitate operation of the well at that capacity.
Cost
The facilities to be constructed under this alternative include: thirty-five shallow
—9—
-------
wells and one pump replacement or modification. The estimated construction cost
of said facilities including engineering and project contingency expenses has
been estimated at $1,47O 0O3. Annual debt service expense on that amount calcula-
ted at 12% for 30 years is $182,485. Other annual costs such as power and chlorine
are approximately proportional to usage and would not change noticeably as a
result of the above-described facility additions.
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 48 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements wi i riot change as a consequence of this fluoride reduction
alternative.
ALTERNATIVE MO. 2: TREATMENT
Method
This solution would involve the treatment of a portion of water produced at each
of the three existing wells utilizing the activated alumina process. Plants num-
bered 1 and 2 will be served by two 700 6PM treatment systems. The 250 6PM well
at Plant #3 will be served by a 170 6PM system. The remainder of the flow will
be blended yielding a combined system capacity of 2250 6PM. The system will also
include a wastewater equalization brine tank to minimize hydraulic impact on the
sanitary sewer system.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
-10-
-------
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $1,650,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $204,831
• Operations and Maintenance 167,169
Total Estimated Annual Cost Increase $372,000
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 42 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level re-
quired by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
—11—
-------
TOWN OF MT. PLEASANT
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Treatment
2,460
2,250
l82,485
$204,831
-
$167,169
$35.09
$71.54
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
o Existing monthly rate $8.50
o Estimated monthly increase 2.92
Adjusted Monthly Water Rate $11.42/consumer
—12-
-------
REFERENCES
‘Personal communication, Ron Bycroft, Town of Mt. Pleasant, January 23, 1980.
2 Personal communication, Ron Bycroft, Town of Mt. Pleasant, February 1, 1980.
3 Clark, J. W., et al., Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
-l 3-
-------
FLUORIDE REDUCTION
I
PUBLIC WATER SUPPLY
OF
THE CITY OF MYRTLE BEACH
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
T ABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Future Conditions 3
FLUORIDE REDUCTION
Alternative No. 1: Treat Existing Wells
Method 5
Cost Estimate 5
Implementation 6
Operator Requirements 6
Alternative No. 2: Regional Water Systen
Method 6
Cost 7
Implementation 7
Operator Requirements 7
Sumary 7
REFERENCES
APPEND ICES
Regional Water System
Fluoride Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking !ater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
fti- i ent res onsibility for the standards was requested by and subsequently
to th ? S uin Ca,oi na Department of i alth and Environmental Control
(C 1EC). investigations conducted by the State revealed that approximately
C’ .‘jbl ic waler suppi es exceeded the established fluoride standard. SC DHEC
ersonnel have worked with the affected communities in a concerted effort to
dE\’eloD rational solutions to the problem. This report, which was funded by
EP. and p e ared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In Janua -v, 1980. a study of each community water supply which exceeded the
legal I1R’lt for fluoride was initiated. The established objective of that in-
yes ti gati e effort was to i denti fy one or more viable fluoride reduction al ter-
natives icr each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the City of Myrtle Beach. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Myrtle Beach water system presently has 21 wells in service. 1 These are
distributed throughout its very linear distribution system which parallels the
Atlantic Ocean. Two more wells are beinq drilled as of this writing. The wells
generally have a pumping capacity of from 200 to 460 gallons per minute (GPM).
These wells generally have multiple screens located from 300 to 710 feet deep
which are opposite what is known as the Black Creek aquifer. This aquifer is
generally located from a depth of 200 feet down to a depth of 1,000 feet in the
Myrtle Beach area, but the lower 200 feet is salty (chloride concentration above
250 mg/i). T’ie ,aters fro i these wells are reported to have fluoride concentra-
tions which range from 3.5 up to 5.2 mg/i depending on the location of screens
and local conditions. The Conway office of the U. S. Geological Survey (USGS)
has indicated that, to their knowledge, all waters from the Black Creek aquifer
in the area have fluoride concentrations which are typically twice to four times
greater than the legal limit of 1.6 mg/i.
A test well program is currently being conducted by the USGS to determine the
quantity and quality of shallow ground water in the Myrtle Beach area. The re—
suits of this testing could indicate that the use of shallow ground water is prac-
tical. However, previous and current testing indicates that variable and rela-
tively low yields should be expected from shallow aquifers in the area. There-
fore, to date no data exists to encourage the belief that sufficient, good
quality, or even treatable iron laden, shallow ground water exists to meet the
City’s current maximum water demand which occurs during the tourist season.
-2-
-------
The Myrtle Beach water system contains 6500 metered connections, many of which
serve multi-family housing units and commercial establishments. Utilizing the
average residential water bill, 4 it was estimated that service is provided to
the equivalent of 10,000 single family users. Accordingly, that estimated con-
sumer population will be utilized to assess the financial impact that fluoride
reduction will have on this community. (See page 7 of this report)
During the 1979 summer season, Myrtle Beach was able to pump approximately 10
million gallons per day (MGD)’ or 6,945 GPM which just met the peak day demand.
For the peak month (July), billed water consumption averaged 8.232 MGD. 2 The
billed water consumption 2 plus the estimated leakage for 1979 averaged approxi-
mately 5.7 MCD.
FUTURE C0 DITI0NS
Future water supply needs have been estimated by Consoer, Townsend & Associates,
Ltd., engineers for Myrtle Beach, to be 13.33 MCD for 1990 and 15.0 MGD for the
year 2000.1 The intermediate plan to meet the increasing water demand is to
rehabilitate a selected few wells each year and install new wells as needed to
stay ahead of the demand. This plan would be followed until a more permanent
solution to the quantity and quality deficiencies can be achieved.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consur 1 ier levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternat 4 ve was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of tne various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
cperating costs with respect to anticipated construction schedules.
One possible solution to the fluoride problem which will not be discussed herein
is the use of the intracoastal Waterway as a source of supply for a surface water
treatment facility. iyrtle Beach has contracted with USGS to study this possi-
bility in detail. However, the results of that study will not be available for
an indeterminate period of time. Accordingly, SC DHEC personnel elected to
forego the evaluation of the waterway source due to insufficient data on the
quality and quantity of raw water. 5
-4-
-------
ALTERNATIVE 110. 1: TREAT EXISTING WELLS
Method
This solution would involve the treatment of the 23 existing wells plus those
wells which are added in the future. For this study, it will be assumed that
27 wells will be in service.
The treatment process which appears to be the least expensive to reduce the fluo-
ride concentration is the activated alumina process. This process would involve
treatment of a portion of the flow from each well and the blending of the bypassed
portion with the defluoridated water. Ihen the treatment capacity is exhausted,
the unit must be regenerated and the backwash discharged to the City’s sanitary
sewer system. For a description of the activated alumina process, see the Appen-
dix entitled “Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $9,395,000
• Annual added debt service assuming 12% loan for 30 years $1,166,295
• Annual added operation cost using 1979 water use $1,056,500
• Total estimated added annual cost $2,222,795
Impl ementati on
It has been estimated that design, securing of permits and apprvoals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 54 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state
—5—
-------
license system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an A operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the comunity for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
ALTERNATIVE £10. 2: REGIONAL WATER SYSTEM
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains would convey the
water in a westerly direction as far as Conway, in a southerly direction as far
as Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
See 4 the Appendix entitled “Regional Water System” for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallons. At the current average daily demand of
5,700,000 gallons, annual cost to this community would be $6,137,475 .
-6-
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternattve can be accomplished
within 60 nionths of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are surnina—
rized in the followinq table.
MYRTLE BEACH
ALTERNATIVE SUI 1r1ARY
Alternative
Capacity
(GPFI)
Annual Cost Data
Capital
Operating
Per Eq. Resd. Consumer
No. 1: Treatment
No. 2: Regional
9460
9257
$1,166,295
$5,543,490
$1,056,500
$ 593,985
$222.28
$613.75
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate $8.60
• Estimated monthly increase 18.52
Adjusted Monthly 1Jater Rate $27.12/consumer
—7—
-------
REFERENCES
‘Interim Water and Sewer Report for City of Myrtle Beach, by Consoer, Townsend
& Associates, Ltd., dated October, 1979, and revised December, 1979 and
January, 1980.
2 Typed data on past water consumption received from Bill Bull, Superintendent of
tIater and Wastewater Division of Myrtle Beach, during January 29, 1980 meeting.
3 Pleeting and discussion with Fred Soland of DHEC on March 4 and 5, 1980.
4 DHEC Staff Study on Fluoride for Myrtle Beach, dated March 1, 1978.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
MYRTLE BEACH AIR FORCE BASE
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirement 2
Existing Supply 2
FLUORIDE REDUCTION
Alternative No. 1: Blending
Method 3
Cost 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Water Purchase
Method 6
Cost 6
Implementation 7
Operator Requirements 7
Suniliary 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DREC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected comunities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC D}-IEC, is a direct outgrowth of that
effort.
In January, 1980. a study of each comunity water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Myrtle Beach Air Force Base. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BAC KGROUND
CONSUMERS
The family housing area at Myrtle Beach Air Force Base contains 865 single family
dwelling units.’
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this community is not readily available. Con-
sequently, system averages developed from records of similar communities were
utilized as a basis for establishing assumed values which will be utilized in
ensuing sections of this report. An average daily usage of 200 gallons per connec-
tion and a maximum daily demand factor of 180% were used to establish the following
system demand data:
• Average Daily Demand 173,000 Gallons
• Maximum Daily Demand 311,400 Gallons
Supply Regui rement
Utilizing a regulatory design criterion requiring that the well or wells be capa-
ble of meeting the maximum daily demand in a 16-hour operating period, the present
supply requirement was calculated to be 325 GPM.
Existing Supply
The housing area is connected to a central system that serves the entire air base.
That system is supplied by three operating deep wells each having an approximate
capacity of 400 GPM. Two elevated storage tanks ride on the system. One 300,000
gallon tank is located in the housing area, the other, a 200,000 gallon structure,
2
is located in the cantonement area.
—2—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE £10. 1: BLENDING
lie thod
Blending deep and shallow well water in the proper portions will reduce the fluo-
ride concentration in the water supply to acceptable levels. This alternative
will address dividing the existing water system into two separate piping networks
each having its own supply and storage facilities.
One network would serve the base housing area exclusively. The source of supply
would consist of one existing deep well and a series of eight new shallow wells.
-3-
-------
The water would be blended in a shallow/deep ratio of 225 GPM/lOO GPM yielding a
supply with a fluoride concentration of 1.4 mg/i. The blended water would be
disinfected with chlorine and receive an injection of polyphosphates to sequester
iron. Storage would be provided by an existing 300,000 gallon elevated storage
tank.
The other network would serve the cantonement area exclusively. The source of
supply would consist of one operating deep well that is presently located in the
cantonement area and the yield from one of the existing deep wells situated in
the base housing area. Storage will be provided by an existing 200,000 gallon
elevated storage tank.
The success of blending in the base housing area is dependent upon control of the
flow from the deep well. This can be accomplished by throttling the deep well
to provide a flow that is properly proportioned to the shallow well yield. It
should be noted that the adaptability of the existing deep well pump to function
in a throttled mode of operation is questionable. It is beyond the limited scope
of this study to fully evaluate the effect of the significantly reduced pump out-
put. The reader is therefore cautioned that it may become necessary to modify or
replace the existing unit to consistently maintain flow rates less than 200 GPM.
A schematic drawing of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recomended is as follows:
• Eight shallow wells each having a capacity of 30 GPM.
• One equipment building to house chemical feed and level control mechanisms.
• One gas chlorinator.
• One 10,000 gallon pressurized chlorine contact tank.
• One concrete valve pit constructed at the intersection of the deep and
-4-
-------
CANTONEMENT
AREA
PRESSURE
CONTACT TANK
FIGURE 1
BASE HOUSING
AREA
PIPE EXISTING DEEP WELL
TO CANTONEMENT AREA
EXISTiNG
ELEV. TANK
EXISTING
DEEP WELL
tft,
= — ii: = $ = i = I
/
CONSTRUCT 8
SHALLOW WELLS
/L
EQUIPMENT BLDG.
WITH CHLORINATOR &
CHEMICAL FEED
FACI LITI ES
SCHEMATIC DIAGRAM OF PROPOSED
WATER SYSTEM ADDITIONS
AT
EXISTING
ELEV. TANK
SEGREGATE SYSTEMS
BY CLOSING EXISTING
VALVES
F
/
MYRTLE BEACH AIR FORCE BASE
-------
shallow well lines. The pit should contain meters and valves on both
supply lines.
• Polyphosphate mixing and feed facilities. The concept presented herein
utilizes a single chemical feed point in the common main leading from the
shallow wells. However, it should be noted that iron must be in a soluble
form for sequestering to be effective, and that pumping and/or conveyance
may cause the iron to precipitate. Should that situation occur, the chemi-
cal feed point may have to be moved or iron treatment may become necessary.
Cost
The construction cost of Alternative No. 1 including engineering and project con-
tingency expenses has been estimated at $380,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $47,173
• Operations and Maintenance 177
Total Estimated Annual Cost $47,350
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Regui rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
—5—
-------
ALTERNATIVE NO. 2: WATER PURCHASE
Method
As is discussed in Alternative No. 1, the base distribution system would be divi-
ded and the existing deep wells utilized as a source of supply for the cantonement
area. The base housing area would be served through a metered connection from the
municipal system serving Myrtle Beach.
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $45,000. Annual costs are summarized
below.
• Debt Service on a 30—Year Loan at 12% $ 5,586
• Water Purchase 35,992
Subtotal $41,578
• Less Power Cost 1 ,578
Total Estimated Annual Cost Increase $40,000
The water purchase expense listed above was calculated at $0.57 per 1000 gallon,
the prevailing bulk rate charged by the City of Myrtle Beach. It should be noted
that the City was included in this study and that it, too, will incur additional
expenses as a result of reducing the fluoride concentration in the water supply.
Assuming a uniform amortization of the cost associated with the least expensive
alternative developed for Myrtle Beach, the bulk rate would increase from
$0. 57/1000 gallon to $1.64/bOO gallon. Utilizing the higher rate, the above
listed water purchase expense was recalculated to be $103,558, bringing the total
estimated annual cost of Alternative No. 2 to $107,566 .
-6-
-------
Impi ementati on
The implementation of this alternative is solely dependent on the availability
of water from Myrtle Beach. As of this writing, the minimum time required is
estimated at 36-60 months.
Operator Requi rements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
MYRTLE BEACH AIR FORCE BASE
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Purchase
325
N/A
$47,173
$ 5,586
$ 177
$101,980
$ 54.74
$124.35
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Presum-
ing that the increased annual cost will be amortized uniformly over the existing
consumer population, the annual incremental increase was calculated to be $54.74
per consumer ($4.56/month).
-7-
-------
REFERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study for
Myrtle Beach Air Force Base, Harry County,” undated.
2 Personal communication, Dan Bender, Myrtle Beach Air Force Base, April 24, 1980.
3 Persona1 communication, Jay Hood, Myrtle Beach, April 25, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
SURFSIDE BEACH
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AtIARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Future Conditions 2
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blending
flethod 4
Cost Estimate with Iron Sequestering 6
Cost Estimate with Iron Removal 6
Implementation 6
Operator Requirements 7
Alternative No. 2: Fluoride Removal Treatment
Method 7
Cost Estimate 7
Implementation 8
Operator Requirements 8
Alternative No. 3: Regional Water System
Method 8
Cost 9
Implementation 9
Operator Requirements 9
Summary g
REFERENCES 11
APPENDICES
Regional Water System
Fl uori de Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Surfside Beach. In addition to addressing
the conceptual solution from a technical standpoint, planning-level cost estimates
are also presented. It should be noted that all capital costs are presented in
1980 dollars and that all operating expenses were calculated at 1979 water produc-
tion and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Surfside Beach water system presently has two wells in service. The larger
of the two, which is pumped at 550 GPM, is used almost exclusively with the smaller
well, which is pumped at 190 GPM, used as a back-up supply only.’ The larger well
has a measured fluoride concentration of approximately 3.0 mg/i and an iron concen-
2
tration of less than 0.1 mg/i. The larger well has screens located from 419 to
469 feet and from 596 to 616 feet deep. The fluoride concentration of the smaller
3
well is reported to be approximately 2.6 mg/i , its iron concentration is not
known.
The system has a 300,000 gallon elevated tank which serves as the Town’s water
storage. To the system operator’s knowledge, 1 the shallower ground water contains
iron in unacceptable concentrations. Therefore, it has typically not been used and
little is known about the water’s quality or quantity.
In 1979, Surfside had approximately 1485 water service connections which used on the
average for the year approximately 0.336 MGD. The average water use for the peak
two-month period during 1979 was approximately 0.463 MGD and the peak day water use
was approximately 0.865 MGD.
FUTURE CONDITIONS
1
The following table gives past and projected customer connections and water demands.
SURFSIDE BEACH
EXISTING AND PROJECTED CONSUMER DATA
Year
Connections
Peak Month
(PIGD)
Peak Day
(MGD)
1976
1977
1978
1979
1990
2000
1310
1374
1432
1485
2500
3400
0.389
0.551
0.546
0.463
0.800
1.105
0.739
0.698
0.834
0.865
1.40
1.88
-2-
-------
As can be seen above, the present pumping capacity of 740 GPfI or 1.065 MGD is ade-
quate to meet the current demand in approximately 20 hours of pumping. However,
additional pumping capacity will be needed in the near future. Recognizing this,
the Town is seeking funds at this time to construct a new well and elevated tank.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction alter-
natives for the subject water system. Each alternative was subsequently evaluated
to determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
sults of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1890 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Method
This alternative would involve the drilling of new wells to replace or blend with
the existing high fluoride wells. This alternative is heavily dependent upon the
quantity and quality of low fluoride ground water available, both of which are
unknown. Therefore, for this to be a viable solution, test and water zone sampling
-4-
-------
wells must be drilled near each existing well to be used and sufficient, satis-
factory water located to replace or blend with the existing well water.
Since it is desirable to plan for future conditions, the 1985 peak day water de-
mand of 1.15 MGD has been selected as the design condition for this alternative.
Also, a 16 hour pumping period has been selected to meet this demand which would
require 1200 GPM of pumping capacity. To achieve this capacity, it appears only
marginally practical to assume that sufficient, acceptable low fluoride ground
water can be located to blend with, let alone to replace, the existing well water.
Therefore, it will be assumed that blending is necessary and that the proper blend
can be achieved by replacing an existing pump with a smaller pump of the desired
pumping rate where required.
Assuming that the available blend water will have a fluoride concentration of
0.2 mg/i or less, the following table gives the amount of blend water required
for an acceptable fluoride blend and the maximum blend water iron concentration
which will give a 1.0 mg/l iron blend. The 1.0 mg/i iron concentration is some-
what arbitrary since one critical factor for this alternative to be a relatively
low cost solution is that the iron in the blended water must either be less than
0.3 mg/l, which appears unlikely, or be suitable for sequestering to achieve an
acceptable water. To allow a safety factor, a 1.4 mg/l fluoride concentration
has been used as the acceptable concentration.
SURFSIDE BEACH
BLENDING DATA
Existing Wells
Proposed Wells
Well
Fluoride
(mg/i)
Iron
(mg/i)
Reduced
Capacity
(Gal/ N Un)
Capacity
(Gal/F un)
Iron
(mg/i)
#2 2.6
#3 3.0
) 190
0.10 353
A
190
467
1.68
-5—
-------
Based on estimates received from a representative of the South Carolina Water Re-
sources Commission (WRC) 4 , it will be assumed that shallow wells will produce
approximately 60 GPM of low fluoride water on the average. Therefore, multiple
wells and well lots with connecting piping will be required to serve the two
existing wells. It will also be assumed that iron sequestering units will be re-
quired at existing well site. To indicate the impact of excessively high iron
content in the new wells, the cost of iron removal treatment has also been esti-
mated. However, it is beyond the scope of the study to predict whether or not
sufficient, acceptable water will be located or whether iron removal treatment
would be required.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$700,000
$ 86,905
$ 3,360
$ 90,265
Cost Estimate with Iron Removal
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using 1979 water use
• Total estimated added annual cost
$1 ,200,000
$ 148,980
$ 20,000
$ 168,980
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendum, rate structure studies,
funding procurement, etc., provided only iron sequestering is required. It is
estimated that the time would increase to 42 months if iron removal treatment is
requi red.
—6—
-------
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative. Should iron removal treatment become necessary, it is
anticipated that one or more additional water system operators may be required.
Therefore, the cost of one operator has been added to the estimated operating
cost.
ALTERNATIVE NO. 2: FLUORIDE REMOVAL TREAT 1ENT
Method
This solution would involve the treatment of the water from the two existing wells
plus the proposed well, which will be assumed to be a 460 GPM well. This will
make the treated water yield approximately equal with that of the previous alter-
native. The treatment process which appears to be the least expensive to reduce
the fluoride concentration is the activated alumina process. This process would
involve treatment of a portion of the flow fron each well and the blending of the
bypassed portion with the defluoridated water. When the treatment capacity is
exhausted, the unit must be regenerated and the backwash discharged to the proposed
sanitary sewer system. For a description of the activated alumina process, see
the Appendix entitled “Fluoride Treatment”.
Cost Estimate
O Capital cost estimate for project design and construction $1,115,000
• Annual added debt service assuming 12% loan for 30 years $ 138,416
O Annual added operation cost using 1979 water use $ 102,750
• Total estimated added annual cost $ 241,166
-7—
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state
license system requires a high school education, four years experience as an
operator in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the community
for this training is anticipated to be approximately $3,000 plus travel and liv-
ing expenses.
ALTERNATIVE NO. 3: REGIONAL UATER SYSTEM
Plethod
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains would convey the
water in a westerly direction as far as Conway, in a southerly direction as far
as Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
-8-
-------
See the Appendix entitled “Regional Water System” for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1000 gallon. At the current average daily demand of
336,000 gallons, the annual cost for Surfside Beach would be $361 ,788.
Impi ementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required refdrendum, rate structure studies,
funding procurement, etc.
Operator Requirements
0per tor requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are sunrna-
rized in the following table.
SURFSIOE BEACH
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
Flo. 2: Treatment
No. 3: Regional
1,167
1,170
972
$ 86,905
$138,416
$326,774
$ 3,360
$102,750
$ 35,014
$ 60.78
$162.40
$243.63
-9-
-------
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this comunity.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate 5 $12.00
• Estimated monthly increase 5.07
Adjusted Monthly tIater Rate $17.07/consumer
-10-
-------
REFERENCES
1 Meeting and discussion with Mr. J. D. Felix, Water Superintendent for Surfside
Beach, on January 28, 1980.
Water Analysis on Surfside Beach Well #3, dated April 2, 1980.
3 Water analysis on Surfside Beach well water, dated June 7, 1978.
4 Telephone communication with Larry West of the S. C. Water Resources Commission,
Conway Office, on April 8, 1980.
5 DHEC Staff Study on Fluoride for the Town of Surfside Beach, dated April 19, 1978.
—11—
-------
FLuORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
SYCAF1ORE ACRES SUBDIVISION
LEXINGTON COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEftLTH
ND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION • 1
BACKGROUND
Existing Conditions 2
Estimated Peak Water Demand 3
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Method 5
Cost Estimate 6
Implementation 6
Operator Requirements 7
SUHMARY . 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each comunity water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Sycamore Acres Subdivision. In addition
to addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Sycamore Acres water system presently has two wells in use. Well #1,
which is on Maple Road, is reported 1 to have an approximate pumping rate of
47 GPM under system pressure and Well #2, which is on Sycamore Drive, is
reported 1 to have an approximate pumping rate of 50 GPM under system pressure.
Well data reports indicate that Well #1 is 310 feet deep and Well #2 is 290
feet deep. The South Carolina Department of Health and Environmental Control
(DHEC) Staff Study on Fluoride 2 indicates that the average fluoride concentra-
tion in the system is 1.9 mg/i. The system has two 5,000 gallon pneumatic
tanks for water storane, one at each well site.
The Sycamore Acres water system is connected to, but presently valved off from,
four adjoininq, interconnected subdivisions which have an acceptable fluoride
concentration in their water. The four systems are operated by the same water
company which operates the Sycamore Acres system, Carolina Water Services, Inc.
The systens are Grayland Forest, Spring Hill, Spring Lake, and Laurel Meadows.
3
The Sycamore Acres system served an average of 91 customers during 1979,
2
although it has been reported that 96 taps exist. Of the 91 customers, 89
were sinqie family residences with an estimated 3.5 persons per residence and
two were stores. The metered water use of the customers durino 1979 averaged
3. . . .
18,332 GPD which is approximately 202 GPD per customer. This subdivision has
not grown at all during the last few years and is not expected to grow in the
near future.
-2-
-------
ESTIMATED PEAK WATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day water
use, 4 and that 96 customers exist, the water demand would be 34,811 GPD. With
that demand, the desirable minimum pumping rate would be 36.3 GPM, which would
allow the estimated peak day water demand to be pumped in 16 hours. Therefore,
the existing 97 GPM supply capacity is quite adequate.
If Ameen’s method 5 for predicting instantaneous water demand on the supply system
is used, the estimated demand would be 96 resd. x 2.04 GPMfresd. = 195.8 GPFI.
However, this estimate is based on each residence using from 400 to 500 GPD and
may need to be verified in the field. Using this instantaneous water supply
5
demand, Ameen’s method of checking pneumatic tank capacity indicates that an
additional 2,760 gallons of pneumatic tank capacity would be needed if a new
well capacity of 36.3 GPM, to meet the peak day demand, were used.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 96 customers assumed as design condition.
2. Yield of a new well is assumed to be 36.3 GPM.
3. Existing pressure tank capacity is 10,000 gallons.
4. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Anieen in his book entitled “Community Water Systems” on pages 50
through 55.
Calculations:
1. 96 residences x 2.04 GPF’l/resd. = 195.8 GPM.
2. 195.8 GPII - 36.3 GPM well yield = 159.5 GPM tank demand.
-3-
-------
3. 159.5 GPM x 20 minute demand = 3,190 gallons of stored water needed.
4. Minimum pneumatic tank size = 3,190 x 4 = 12,760 gallons.
5. Additional pneumatic tank capacity needed = 12,760 gallons - 10,000 gallons
= 2,760 gallons. Use 3,000 gallon tank.
—4—
-------
FLUORIDE REDUCTION
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
METHOD
One alternative which might appear to have some possibilities would be the instal-
lation of a new well of at least 36.3 GPM which would tap a lower fluoride water
zone. However, the well log data available does not give much encouragement that
other water zones exist. Also, if another water zone does exist, it could just as
easily have a high fluoride concentration as not.
The most viable alternative for Sycamore Acres appears to be blending their exist-
ing well water with water from the adjoining systems. The adjoining water systems
are reported’ to have an average fluoride concentration of 1.2 mg/l, but their
system elevation and pressure is inadequate to properly serve Sycamore Acres with-
out a booster pump.
The blended flow would be considerably greater than that needed to meet the system’s
estimated instantaneous water supply demand. Therefore, one of the existing wells
-5-
-------
would be utilized as the high fluoride source; the other well would be abandoned.
Blending the yield from Well #2 (50 GPM) with 125 GPM from an adjoining system
would result in a fluoride concentration of 1.4 mg/i.
The booster pumping station would be located near the intersection of Maple Road
and Mineral Springs Road near the Spring Hill Subdivision. 1 That site is approxi-
mately 61 feet lower in elevation and 4,200 linear feet from the Well #2 site. 1
The booster pump installation would consist of the following:
• A ground storage suction tank (6,000 gallons t) with automatic water level
control valve;
• A 125 GPM booster pump wired to operate simultaneously with the Well / /2 pump,
and;
• 6” piping from the booster pump to Well #2.
COST ESTIMATE
• Capital cost estimate for project design and construction $50,000
• Annual added debt service assuming 12% loan for 30 years $ 6,208
IMPLEMENTATION
It has been estimated that design, securing of approval, advertisement, contract
execution, and construction on this alternative can be accomplished within 18
months of the completion of required referendums, rate structure studies, funding
procurement, etc.
OPERATOR REQUIREMENTS
Operator requirements for this system are not expected to change as a consequence
of this alternative.
—6—
-------
SUMMARY
Based upon available information, the most practical and least expensive method
of solving the fluoride problem for the Sycamore Acres Subdivision appears to be
to construct the blending project described above. Presuming that the increased
annual cost will be amortized uniformly over the existing customer population of
approximately 91, the annual incremental increase is calculated to be $68.22 per
consumer ($5.69/month).
—7—
-------
REFERENCES
Personal comunication with Mr. Rob Burgun of Johnny 1. Johnson and Associates,
Inc., Columbia, South Carolina on March 31 and pril 1, 1980.
Staff Study for Sycamore Acres, Lexington County, dated March 22, 1978.
3 personal communication with Dolly Lewis of Carolina Water Services, Inc.,
W. Columbia, South Carolina on March 31, 1980.
4 Clark, J. W., et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pennsylvania.
5 Ameen, Joseph S., Cornunity Water Systems , pages 50-55, 1971, Technical
Proceedinas, Post Office Box 5041, High Point, North Carolina.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
WAGON WHEEL FARMS SUBDIVISION
GEORGETOWN COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. Sirrine Company and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION. 1
BAC KGROUND
Existing Conditions 2
Estimated Peak Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Alternative No. 1: Drill New Well
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Purchase Water from GCWSA
Method 6
Cost Estimate 6
Implementation 7
Operator Requirements . . . . 7
Summary 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking later Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Wagon Wheel Farms Subdivision. In addi-
tion to addressing the conceptual solution from a technical standpoint, planning-
level cost estimates ar also presented. It should be noted that all capital
costs are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Wagon Wheel Farms Subdivision water system has one 60 GPM well and a 500
gallon pneumatic water storage tank in service. The well is reported to have
a fluoride concentration of approximately 4.4 mg/i and an iron concentration
of less than 0.1 mg/i. The water system is approximately 300 feet away from
a water line owned by the Georgetown County Water and Sewer Authority’s Murrell’s
Inlet system.
Water use in this system is not metered. The owner has advised that the 40
existing mobile home trailers are occupied only during the summery The system
has 50 approved taps. Assuming the trailer park is full and average use during
the summer is 200 GPD per trailer, the estimated average daily water demand would
be 10,000 GPD.
ESTIMATED PEAK WATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 3 the water demand woul’d be 18,000 GPD. With that demand, the de-
sirable minimum pumping rate would be 18.8 GP 1, which would allow the esti-
mated peak day water demand to be pumped in 16 hours. If Ameen’s method 4
for predicting instantaneous water demand on the supply system is used, the esti-
mated demand would be 150 GPM. However, this estimate is based on each residence
having four persons who use a total of from 400 to 500 GPD. Since this system
serves a trailer park, DHEC has indicated 6 that 80% of P meen’s instantaneous de-
mand can be used as the estimated demand. Using this instantaneous water supply
-2—
-------
demand, Imeen’s method 4 of checking pneumatic tank size indicates that a well
capacity of at least 113.7 GPM would be needed if the existing 500 gallon tank
is all the storage available. However, since the 60 GPM well with the 50 gallon
tank has evidently met the demand in the past, it appears that the instantaneous
demand is not more than 60 GPM plus the tank contribution for 20 minutes. Using
this demand, an additional 4,000 gallons of pneumatic tank capacity should allow
the use of a new 18.8 GPM well, which should be able to meet the peak day de-
mand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 50 residential connections assumed as design condition.
2. Existing pressure tank size is 500 gallons.
3. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. I meen in his book entitled “Community Water Systems” on pages 50
through 55, except that instantaneous demand is reduced to 80% of Ameen s
estimate.
Calculations:
1. 50 residences x 3.0 GPM/resd. x 0.8 = 120 GPM instantaneous demand.
2. Usable pressure tank volume = 500 4 = 125 gallons.
3. Tank contribution for 20 minutes = 125 20 minutes 6.3 GPM.
4. Minimum new well size to meet Ameen’s instantaneous supply demand = 120 GPM
— 6.3 GPM = 113.7 GPM.
5. Instantaneous demand = 60 GPM (well) + 6.3 GP 1 (tank) = 663 GPfI
6. Minimum storage with 18.8 GPM well = (66.3 - 18.8) x 20 minutes = 950 gallons.
7. Minimum pneumatic tank capacity = 950 x 4 = 3,800 gallons.
-3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this comunity. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the re-
suits of the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the comunity’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL NEW WELL
Method
This alternative would involve the drilling of a new well to replace or blend with
the existing high fluoride well. It has been estimated that 18.8 GPM would be
needed to meet the peak water demand; therefore, a replacement well appears to be
more practical than operating two wells. It should be noted that this alternative
-4-
-------
is heavily dependent upon the quantity and quality of shallow ground water avail-
able, both of which are unknown. Therefore, for this to be a viable solution, a
test and water zone sampling well must be drilled and sufficient, satisfactory
water located.
This alternative assumes that one new 19 GPM well with iron sequestering and
chlorine equipment would be constructed. In addition, a new 4,000 gallon pneu-
matic water storage tank would be included. It should be noted that if exces-
sive or non-sequesterable iron exists in the new well, iron removal treatment
would become necessary.
Cost Estimate
• Capital cost estimate for project design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added operation cost using estimated water use $ 22
• Total estimated added annual cost $ 5,609
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of funding procurement, etc.
Operator Requi rernents
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: PURCHASE WATER FROM GCWSA
Method
This alternative would involve the installation of a master water meter and approx-
—5—
-------
imately 300 feet of connection main between the Wagon Wheel Farms system and
Georgetown County Water and Sewer Authority’s (GCWSA) Murrell’s Inlet system.
It should be noted that connection to GCWSA will not eliminate the high fluo-
ride problem until GCWSA corrects their own problem.
GCWSA has advised 5 that they should have the following service connection and
water rates in effect by the end of June, 1980:
• 3/4” residential connection fee would be $320
• Minimum residential service rate would be $6.47/month
• Charge for all water used would be $0.97/bOO gallons
• 2” comercial tap and meter installation fee would be $1 ,000
• 3” commercial tap and meter installation fee would be $2,000
• Comercial water service rates are assumed to be basically the same as the
residential rates.
In addition to the above, an increase of approximately $1.15 per 1000 gallons
must be added to cover the minimum cost which GCWSA is expected to incur in solv-
ing their fluoride problem.
Cost Estimate
• Capital cost estimate for connection installation $4,000
• Annual added debt service assuming 12% loan for 30 years $ 497
• Annual added water cost, less power cost, with estimated use $5,420
• Total estimated added annual cost $5,917
Implementation
It has been estimated that securing of approvals and a water service contract,
and construction of this alternative can be accomplished within 18 months of the
completion of funding procurement, etc.
-6-
-------
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
WAGON tIHEEL FARMS
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
10. 1: New Well
(assuming iron
sequesteri ng)
No. 2: Purchase
Water
19
Fl/A
$5,587
$ 497
$ 22
$5,420
$140.23
$147.93
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Presum-
ing that the increased annual cost will be amortized uniformly over the existing
consumer population, the annual incremental increase was calculated to be $140.23
per consumer ($11.69/month).
-7-
-------
REFERENCES
1 DHEC Water Analysis, Sampling Point: Wagon Wheels Farms, Station Code 422001,
Laboratory Sample No. 9100850055, dated October 28, 1975.
2 Meeting and discussion with Mr. Welch, the owner, on February 7, 1980.
3 Clark, J. W., et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pa.
4 Ameen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical Proceed-
ings, Post Office Box 5041, High Point, North Carolina.
5 Telephone conversation with Barry Green of Georgetown County Water and Sewer
Authority, on April 15, 1980.
6 letter from Fred H. Soland of DHEC to Joe Wilison of JESCO dated May 5, 1980.
-8-
-------
APPENDIX
REGIONAL WATER SYSTEM
-------
REGIONAL WATER SYSTEM
A regional water system which would serve the major coastal communities in Horry
and Georgetown Counties was evaluated during the course of this study. The sys-
tem would be supplied by a 35 IIGD conventional surface water treatment facility
located on the northeastern bank of the Pee Dee River at the U.S. Highway 701
crossing.
It was assumed that all water systems within reasonable proximity of the proposed
transmission mains would be connected. A list of the water systems involved is
included at the end of this narrative. The list also contains current and pro-
jected water use data.
The transmission lines were sized to maintain a 2.0 to 3.0 foot per second
velocity in the mains at the peak day water demand estimated for 1990. At these
velocities, pressure losses would be small enough to preclude the use of booster
pumping stations. Service pumps located at the treatment facility would maintain
pressure gradients above the overflow elevations of existing water tanks located
on the user systems. Connections to those tanks would require the use of altitude
valves.
The capital cost of the regional water system was estimated to be $85,000,000.
The transmission mains accounted for approximately 70% of that cost. Calendar 1980
operation, maintenance and equipment replacement costs were estimated to be
$1 ,143,000. Each user system served would purchase water through a master meter
at a unifom rate. Utilizing current usage data and assuming that the plant opera-
ted during calendar 1980, the unit price would be $2.95 per 1000 gallons.
RS-l
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE CITY OF NORTH fIYRTLE BEACH
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, [ NC.
-------
Operator Requirements
Alternative No. 2: Treat Existing Wells
Method
Cost Estimate
Implementation
Operator Requirements
Alternative No. 3: Regional Water System
Method
Cost
Implementation
Operator Requi rements
Summary
REFERENCES
APP ENDI CES
Regional
Fluoride
Blendinq
Water System
Treatment
Graph
Page
1
2
2
4
6
6
7
7
7
8
8
8
9
9
9
9
10
11
TABLE OF CONTENTS
INTRODUCTION
BACKGROUND
Existing Conditions
Future Conditions
FLUORIDE REDUCTION
Alternative No. 1: Drill Wells for Blendinc’
Method
Cost Estimate with Iron Sequestering
Cost Estimate with Iron Removal
Irnpl ementati on
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tiater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcernent responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the City of North Myrtle Beach. In addi-
tion to addressing the conceptual solution from a technical standpoint, planning—
level cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The North Myrtle Beach water system includes, at the time of this writing, eight
wells, four elevated water storage tanks, and a generally linear distribution
system which parallels the Atlantic Ocean. The water tanks have a combined capac-
ity of 650,000 gallon. Chlorination is the only treatment utilized at the wells.
The design pumping rates and approximate fluoride concentrations of each well are
listed in the following table.
NORTH MYRTLE BEACH
EXISTING WELL DATA
Uell
.1
Capacity
(Gal/Mm)
.2
Fluoride
(mg/i)
#1 41st Ave. S.
#2 Stuckeys 27th Ave. S.
#3 Possum Trot 13th Ave. S.
#4 Hillside & 9th Ave. S.
#5 Fire Station
#6 Vereen
#7 Sea Mountain
#8 White Point
350
300
500
250
500
500
500
500
5.4
5.0
4.7
4.7
5.2
5.2
The system served approximately 47001 consumers in 1979 and delivered an esti-
mated 1.6 MGD 1 as an average for the year. The average water consumption for the
three sumer months was estimated to be approximately 2.5 MGD and the peak day
water demand for 1979 was approximately 3.5 MGD. 3
FUTURE CONDITIONS
Future water supply needs have been estimated by the City’s consulting engineer
1
to be 4.8 MGD for 1985 and 5.4 MGD for 1995. Using those rates, the maximum water
supply rate needed for 1990 was estimated to be 5.1 MGD. The Waccamaw Regional
-2-
-------
Planning and Development Council furnished an estimate of 6.0 MGD for the water
supply needed in the year 2000, which appears to be in line with the Harwood
Beebe Company estimates.
As of this writing, two additional wells and two additional elevated water storage
tanks are under construction. 1 It is anticipated that these wells will yield
water of basically the same quality as the existing facilities. The proposed
1
yields were given as 500 GPM each. If this yield is achieved, North Myrtle Beach
will have a pumping caoacity of 6.336 MGD which would be greater than the estimated
supply requirement for the year 2000.
-3-
-------
FLUORIDE REDUCTION
Preliiiinary investigative efforts identified two viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to deter-
mine the most practical and least expensive method of effecting a solution to the
fluoride problem. The ensuing paragraphs of this report document the results of
the evaluations and rank the alternatives in their order of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL WELLS FOR BLENDING
Method
This alternative addresses construction of new wells to blend with the existing
high fluoride wells. Blending is heavily dependent upon the quantity and
quality of shallow ground water available, both of which are unknown. Therefore,
for this to be a viable solution, test and water zone sampling wells must be
drilled near each existing well to be used and sufficient, satisfactory water
located to blend with the existing well water. There is no assurance that suffi-
cient, satisfactory water exists until testing is completed.
-4-
-------
Assuming that the shallow water will have a fluoride concentration of 0.2 mg/1
or less, the blend ratio graph in the Appendix can be used to determine the re-
quired well capacity. The average quality of the existing wells was used to esti-
mate the quality of water which may be expected from the two wells being constructed.
For this alternative, the design flow will be 4400 GPM which is equal to the exist-
ing well capacity plus the estimated pump rates of the two wells under construction.
The following table gives the amount of deep and shallow water required for an
acceptable fluoride blend, and the maximum shallow well water iron concentration
to achieve a 1.0 mg/i iron blend assuming all deep wells have an iron concentration
of 0.1 mg/i. The 1.0 mg/l iron concentration is somewhat arbitrary since the
critical factor for this alternative to be a low cost solution is that the iron in
the blended water must either be less than 0.3 mg/i, which appears unlikely, or
be suitable for sequestering to achieve an acceptable water. To allow a safety
factor, a 1.4 mg/i fluoride concentration has been used as the acceptable blend
concentrati on.
CITY OF NORTH MYRTLE BEACH
BLENDING DATA
Existing Wells
ProDose’ Wells
Well
Fluoride
(mg/i)
Reduced
Capacity
(Gal/Mm)
Capacity
(Gal/Fun)
Iron
(mg/i)
#1
#2
#3
#4
#5
#6
#7
#8
#9
#10
5.4
5.0*
5.0
4.7
4.7
5.2
5.0*
5.2
5.0*
5.0*
81
75
125
67
133
120
125
120
125
125
269
225
375
183
367
380
375
380
375
375
1.27
1.30
1.30
1.33
1.33
1.28
1.30
1.28
1.30
1.30
*Ass,Jmed to be the average fluoride
concentration in the existing wells
—5-
-------
As indicated in the table, this alternative would require that the existing
deep well pumps will be replaced with smaller pumps to achieve the desired blend.
As a minimum, iron sequestering units are assumed to be needed at each main well
site. Based on estimates received from private contractors 4 and discussions with
South Carolina Water Resources Commission 5 , shallow well yields were estimated
between 75 and 100 GPtI. Therefore, multiple wells and well lots with connecting
piping will be required to serve each deep well. At an average yield of 85 GPM
approximately 40 shallow wells will be required.
Due to the large quantity of shallow well water required for blending, a good
possibility exists that iron removal treatment would be necessary. Accordingly,
the estimated cost of blending with and without iron treatment are presented
below.
Cost Estimate with Iron Sequestering
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using estimated 1979 water use
• Total estimated added annual cost
$2,300,000
$ 285,545
$ 16,000
$ 301 ,545
Cost Estimate with Iron Removal
• Capital cost estimate for project design and construction
• Annual added debt service assuming 12% loan for 30 years
• Annual added operation cost using estimated 1979 water use
• Total estimated added annual cost
$5,100,000
$ 633,165
$ 32,000
$ 665,165
-6-
-------
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 36 months of the completion of required referendum, rate structure studies,
funding procurement, etc., provided only iron sequestering is required. It is
estimated that the time would increase to 54 months if iron removal treatment is
requi red.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative. However, if iron removal treatment becomes necessary, it
is anticipated that at least one additional staff position for a water system
operator would be created. The estimated salary of one operator has been included
in the operating cost estimate.
ALTERNATIVE NO. 2: TREAT EXISTING WELLS
Method
This solution would involve the treatment of the water from the eight existing
wells plus the two proposed wells, which would yield an approximate total of
4400 GPM. The treatment process which appears to be the least expensive to
reduce the fuoride concentration is the activated alumina process. That proc-
ess would involve treatment of a portion of the flow from each well and the blend-
ing of the bypassed portion with the defluoridated water. When the treatment
capacity is exhausted, the unit must be regenerated and the backwash discharged
to the City’s sanitary sewer system. This alternative includes a wastewater equal-
ization tank at the seven largest wells to reduce the hydraulic impact on the City’s
-7-
-------
sanitary sewer during the regeneration process. For a description of the
activated alumina process, see the Appendix entitled “Fluoride Treatment”.
Cost Estimate
• Capital cost estimate for project design and construction $4,915,000
• Annual added debt service assuming 12% loan for 30 years $ 610,148
• Annual added operation cost using estimated 1979 water use $ 461,000
• Total estimated added annual cost $1 ,071 ,148
Irnpl ementati on
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 48 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requi rements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
-8-
-------
ALTERNATIVE NO. 3: REGIONAL WATER SYSTEM
Method
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River near Bucksport. Distribution mains convey the
water in a westerly direction as far as Conway, in a southerly direction as far
as Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisions involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
See the Appendix entitled “Regional Water System” for a more complete description
of the proposed facilities.
Cost
The estimated bulk purchase rate for water drawn from the proposed regional system
is approximately $2.95 per 1,000 gallons. At the current average daily demand
of 1,600,000 gallons, the annual cost would be $1,722,800.
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 60 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
-9-
-------
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
NORTH MYRTLE BEACH
ALTERNATIVE SUMFIARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
(assuming iron
removal)
No. 2: Treatment
No. 3: Regional
4,400
4,400
3,542
$633,165
$610,148
$1,556,067
$ 32,000
$461,000
$166,733
$141.52
$227.90
$366.55
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate 6 $ 6.84
• Estimated monthly increase 11.79
Adjusted Monthly Water Rate $18.63/consumer
-10-
-------
REFERENCES
1 Data provided by: Harwood Beebe Company with letter dated March 7, 1980 and also
by phone conversation with Mr. Hugh Miley, Jr. on March 6, 1980.
2 Chemical analyses “Laboratory Report” by Palmer & Mallard on seven wells, dated
December 16, 1977.
3 lelephone conriunication with Mr. Smith of North Myrtle Beach water department on
April 8, 1980.
4 Weli yields, chemical quality, and costs estimated by Robert B. Heater, President
of Heater Well Company.
5 Telephone communication with Larry West of the S. C. Water Resources Commission,
Conway Office, on April 8, 1980.
6 DHEC Staff Study on Fluoride for North Myrtle Beach, dated April 18, 1978.
—11—
-------
FLOOR IDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
NORTH TRANQUIL ACRES SUBDIVISION
DORCHESTER COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWPRE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirements 2
Existing Supply 3
FLUORIDE REDUCTION
Method 4
Cost 4
Implementation 5
Operator Requirements 5
REFERENCES 6
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January. 1980. a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of North Tranquil Acres Subdivision. In
addition to addressing the conceptual solution from a technical standpoint,
planning-level cost estimates are also presented. It should be noted that all
capital costs are presented in 1980 dollars and that aU operating expenses were
calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
North Tranquil Acres is an established residential subdivision. It is
located in Dorchester County and lies to the south of the Town of Summerville.
The water system serving North Tranquil cres provided water to 175 consumers,
approximately 500 people, as of July, 1978.1
Most building lots in the subdivision are occupied; therefore, the population
is expected to remain static.
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this community is not readily available.
Consequently 7 system averages developed from records of similar comunities
were utilized as a t asis for establishing assumed values which will be utilized
in ensuing sections of this report. An average daily usage of 160 gallons per
connection and a maximum daily demand factor of 180% were used to establish
the following system demand data:
• Average Daily Demand 28,000 gallons
• Maximum Daily Demand 50,400 gallons
Supply Reguirenent
The domestic supply requirement for this comunity was assumed to be the
average flow during a period of maximum demand. Said requirement was computed
to be 35 GPM.
- —2-
-------
A windshield survey of this community confirmed the existence of fire
hydrants. Therefore, it was determined that the supply must have the
capacity to meet both domestic and fire flow requirements.
EXISTING SUPPLY
The existing water supply consists of 3 wells having a combined rated capac—
ity of 270 GPM.’ T Ie water produced by the wells contains 2.6 mg/l fluoride
which exceeds the limit of 1.6 i g/l established by law. 2
- .3-
-------
FLUORIDE REDUCTION
METHOD
Based upon available information, the most practical and least expensive
method of effecting a fluoride reduction in this community is to abandon
the existing supply and purchase water from the Town of Summerville. The
Town owns and operates an existing loll main that traverses the entire length
of North Tranquil Acres along the western side of Ladson Road. The connec-
tion can be made at any point along the above—described main.
COST
The fire flow requirement will dictate the installation of a six-inch connec-
tion and meter. The tap and meter have been estimated to cost 6,OOO. It
will be the owner’s responsi’bflity to obtain a permit from the State Highway
Department to construct a waterline across Ladson Road and to subsequently
install said crossing. For the purpose of estimating the capital cost of
this system, it has been assumed that the conditions of the Highway Department
permit will specify installation of the crossing by boring under the paved
portion of the road.
The estimated construction cost of the complete connection including tap,
meter, bored crossing, engineering and project contingency expenses is $12,600.
Annual debt service expense on that amount calculated at 12% for 30 years is
$1,564. The increase in annual operating expenses for this systerli attributable
to this change was calculated as follows:
-4-
-------
• Debt Service $1,564
• Plus Water Purchase 7,569
Subtotal $9,133
• Less Power Cost 433
Total Annual Increase $8,700
At the current consumer population the annual increase in cost per consumer will
be 4971 ($4.14/month) .
IMPLEMENTATION
Design and construction of the above-described facilities can be accomplished
within 18 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
OPERATOR REQUIREMENTS
Operator requirements for this system will not change as a consequence of fluo-
ride reduction in the water supply.
-5-
-------
REFERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study
for North Tranquil Acres Subdivision, Dorchester County, pril 17, 1978.”
2 South Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Sample No. R06208—1603, June 29, 1978.
3 Personai comunication, Mr. Roy Winey, Town of Sumerville, March 27, 1980.
-6-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
OAKEY SWAMP TRAILER PARK
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepa red For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions . 2
Estimated Peak Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 6
SUMMARY . 6
REFERENCES 7
-------
INTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Iater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DREC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC OHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Oakey Swamp Trailer Park. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Oakey Swamp Trailer Park water system is reported to have two wells and four
pneumatic water storage tanks in service. Well #1 yields approximately 37 GPM,
has a 20 foot screen located between 80 and 100 feet deep, 1 and has a fluoride
concentration of approximately 1.8 mg/l. 2 Well #2 yields approximately 18 GPI1,
has a 20 foot screen located between 280 and 300 feet deep, 1 and has a fluoride
concentration of approximately 3.6 mg/i. 2 The blended water should have a fluo-
ride concentration of approximately 2.4 mg/l. Well #1 has a 5,000 gallon pneu-
matic tank and Well #2 has two 100 gallon and one 175 gallon pneumatic tanks in
.3
service.
Water use in this system is not metered. The system is permitted for a maximum
of 40 trailers. 3 However, the park was less than half full when visited. Assum-
ing the park is full and average water use is 200 GPD per trailer, the estimated
average daily water demand would be 8,000 GPO.
ESTPIATED PEAK tIATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 4 the water demand would be 14,400 GPD. With that deffland, the
desirable minimum pumping rate would be 15 GPM, which would allow the estimated
oeak day water demand to be pumped in l 6 hours. If Ameen’s method 5 for
predicting instantaneous water demand on the supply system is used, the estimated
demand would be 136 GPM. However, this estimate is based on each residence having
four persons who use a total of from 400 to 500 GPO. Since this system serves a
trailer park, DHEC has indicated that 80% of Ameen’s instantaneous demand can be
—2-
-------
used as the estimated demand. Using this instantaneous water supply demand,
Amee&s method 5 of checking pneumatic tank size indicates that a well capacity
of 41.6 GPM would be needed with the existing 5,375 gallons of tank capacity.
However, an additional 2,500 gallons of pneumatic tank capacity would allow
the use of a 15 GPM well, which is estimated to be sufficient to meet the peak
day demand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 40 residential connections assumed as design condition.
2. Yield of new well is assumed to be 15 GPM.
3. Existing pneumatic tank capacity is 5,375 gallons.
4. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Ameen in his book entitled “Comunity Water Systems” on Pages 50
through 55, except that instantaneous demand is reduced to 80% of Ameen’s
estimate.
Calculations:
1. 40 residences x 3.4 GPM/res. x 0.8 = 108.8 GPI1 instantaneous demand.
2. Usable pressure tank volume = 5,375 4 = 1,344 gallons.
3. Tank contribution for 20 minutes = 1,344 20 minutes = 67.2 GPM
4. Minimum new well size to meet instantaneous supply demand = 108.8 GPM -
67.2 GPM = 41.6 GPM
5. Minimum pneumatic tank capacity with 15 GPM well = (109 GPM - 15 GPM) x
20 minutes x 4 = 7,520 gallons
6. Additional pneumatic tank capacity needed = 7,520 gal. - 5,375 gal. =
2,145 gallons. Use 2,500 gallon tank.
-3-
-------
FLUORIDE REDUCTION
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the l 98O calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
METHOD
The viable alternatives for this system appear to be quite limited. Drilling of
additional wells for blending has been tried. The results were a reduction in
the fluoride concentration from 3.6 mg/i in the deep well to approximately
2.0 mg/I with a shallow well which has a 1.8 mg/i fluoride concentration but a
high iron concentration. Another well is reported to have produced a fluoride
concentration of O. 2 mg/i, but its iron concentration was an extremely high 10
mg/i. 6 Iron removal treatment would be extremely expensive for this size system,
probably costing over $400 annually per customer. Therefore, both the blending
and iron treatment solutions have been eliminated as viable alternatives.
The only viable alternative for this system appears to be to connect to the City
of Conway’s water system when the Conway system is extended to this area. This
-4-
-------
alternative would involve the installation of a water meter and approximately
140 feet of connection main between the Oakey Swamp system and a water main along
Highway 78. Conway has planned to loop a water main out Highway 378, down
Highway 78 in front of the Oakey Swamp Trailer Park, and back to Town along
Highway 165. This installation is proposed for completion by the end of 1981.
It should be noted that connection to the Conway system will not eliminate the
high fluoride problem until Conway corrects their own problem.
Conway has advised that they presently charge $2,600 for a 3” water meter instal-
lation, 8 which would probably be required for this trailer park. The City’s pro-
posed water rates, which are likely to be in use by the end of June, 1980, are
$5.00 minimum per dwelling per month for the first 2,000 gallons plus $0.75 per
8
each 1,000 gallons used in addition to the first 2,000 gallons. To this rate,
an increase of $0.64 per 1,000 gallons must be added to cover the minimum cost
which Conway expected to incur in solving their fluoride problem.
COST ESTIMATE
• Capital cost estimate for connection installation $3,500
• Annual added debt service assuming 12% loan for 30 years $ 435
• Annual added water cost, less power cost, using estimated
water use $2,817
• Total estimated added annual cost $3,252
IMP LEMENTAT ION
It has been estimated that design, securing of approvals and a water service con-
tract, and construction of this alternative can be accomplished within 18 months
of the completion of funding procurement, etc.
—5—
-------
OPERATOR REQUIREMENTS
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
Based upon available information, the only viable method of effecting a solution
to the fluoride problem in the Oakey Swamp system is to implement the described
connection to the Conway system. Presuming that the increased annual cost will
be amortized uniformly over the existing customers (assumed to be 20), the annual
incremental increase was calculated to be $162.60 per consumer ($13.55/month).
-6-
-------
REFERENCES
1 fleeting and discussion with Mr. George BesserTt on February 5, 1980.
2 DHEC Staff Study on Fluoride, dated March 16, 1978.
3 DHEC construction permit #20387 and map of system furnished by the Owner.
4 Clark, J. 11., et al., Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pennsylvania.
5 Ameen, Joseph S., Cornunity Water Systems , pages 50-55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, North Carolina.
6 DHEC Water Analysis, Sampling Point: Oakey Swamp Trailer Park, new Well
(shallow), Laboratory Sample No. P 08318-465, dated August 29, 1978, F =
0.2 mg/i and Fe = 10 mg/i.
7 lelephone conversation with Mr. Winfieid, Director of Public Works for Conway,
South Carolina on March 7, 1980. -
8 Telephone conversation with Mr. Winfield, Director of Public Works for Conway,
South Carolina on April 14, 1980.
9 Letter from Fred H. Soland of DHEC to Joe Wilison of Jesco dated May 5, 1980.
—7—
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
PINE RIDGE COMPANY MOBILE HOME PARK
BERKELEY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BAC KGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirement 2
Existing Supply 2
FLUORIDE REDUCTION
Alternative No. I: Water Purchase
Method 3
Alternative No. 2: Blending
Method 4
Cost 5
Implementation 5
Operator Requirements 6
Sumary 6
REFERENCES 7
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop.rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Pine Ridge Company Mobile Home Park. In
addition to addressing the conceptual solution from a technical standpoint, plan-
ning-level cost estimates are also presented. It should be noted that all capital
costs are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—l —
-------
BAC KGROUND
CONSUMERS
The water system serving Pine Ridge Company Mobile Home Park provided service to
22 consumers, approximately 70 people, as of May, 1978.1
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in this cornunity is not readily available. Con-
sequently, system averages developed from records of similar communities were uti-
lized as a basis for establishing assumed values which will be utilized in ensuing
sections of this report. An average daily usage of 160 gallons per connection and
a maximum daily demand factor of 180% were used to establish the following system
demand data:
• Average Daily Demand 3,520 Gallons
• Maximum Daily Demand 6,336 Gallons
Supply Requl rement
Utilizing a regulatory design criterion requiring that the well or wells be capable
of meeting the maximum daily demand in a 16-hour operating period, the supply
requirement for this community was calculated to be 7 GPM.
Existing Supply
The existing water supply consists of two wells of unknown capacity. The fluoride
concentration in said wells is 2.5 mg/i which exceeds the limit of 1.6 mg/l estab-
lished by law. 1
—2-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for the Pine Ridge Mobile Home Park. Each alternative was subsequently
evaluated to determine the most practical and least expensive method of effecting
a solution to the fluoride problem. The ensuing paragraphs of this report docu-
ment the results of the evaluations and rank the alternatives in their order of
desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is placed
in a proper perspective with the community’s present fiscal position. Recognizing
that the cost data is presented in 1980 dollars, it is recommended that initial
planning of any alternative include a reevaluation of capital and operating costs
with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: WATER PURCHASE
Method
This alternative requires the abandonment of the existing supply and connection
to a proposed regional water system. The feasibility of constructing that system
is being studied by the Berkeley County Regional Water and Sewer Authority; there-
-3-
-------
fore, no definitive information relative to the availability or cost of water
service is presently obtainable.
ALTERNATIVE NO. 2: BLENDING
Method
Fluoride reduction can be achieved by drilling one shallow well and blending it
with the yield from one of the existing wells. If the existing wells are approxi-
mately equal in capacity, their operation can be alternated. If not, one should
be taken out of service.
Assuming a fluoride concentration of 0.1 mg/i in the proposed shallow well, a
shallow/deep mix of 1 GPM/l.2 GPM will result in a blend having a fluoride concen-
tration of 1.4 mg/l. Based upon the supply requirement previously calculated
(7 GPrl), a 15 GPM shallow well should be adequate.
The success of blending is dependent upon control of the flow from the deep well.
This can be accomplished by throttling the discharge valve to provide the required
18 GPM which will combine with the new well to produce a total flow of 33 GPM.
Sufficient iron to cause aesthetic problems, such as staining of plumbing fixtures,
should be expected in the proposed shallow well. With the favorable ratio of deep!
shallow well water that will be utilized in this system, it was assumed that the
iron could be sequestered and then diluted sufficiently to preclude the occurrence
of iron related nuisance problems. Feeding a solution of polyphosphates (chemical)
to the shallow wells will provide an economical means of controlling red water.
The chemical is purchased dry in 50 or 100 pound bags and mixed with water to form
a solution. The mixture is then injected into the system by a small pump.
-4-
-------
Shallow wells are generally more susceptible to bacterial contamination than are
deep wells. Consequently, the combined flow should be chlorinated at the inlet
side of the existing pneumatic storage tank.
A schematic diagram of the proposed water supply additions is presented in
Figure 1. A complete list of the facilities recomended is as follows:
• One 15 GPM shallow well including electrical controls and pump.
• One concrete valve pit constructed at the intersection of the deep and
shallow well discharge lines. The pit should contain meters and valves on
both lines.
• One chlorinator
• One polyphosphate mixing and feed system
• One equipment building
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $29,000. Annual costs are summarized
below.
• Debt service on a 30-Year Loan at 12% $3,600
• Operations and Maintenance 25
Total Estimated Annual Cost Increase $3,625
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
—5—
-------
PROPOSED
J SHALLOW WELL
Tol
PROPOSED
PHOSPHATE
FEED
EXISTING
DEEP WELL
I I
PROPOSED
EOUI PMENT
BUILDING
PROPOSED
CHLORI NE
FEED
SCHEMATIC DIAGRAM OF
PROPOSED WATER SYSTEM ADDITIONS
AT
FIGURE 1
D VALVE BOX
EXISTING
500 GAL
PNEUMATIC
TANK
TO CONSUMER
-—T—
PIUE RIDGE MOBILE HOME PARK
-------
Operator Requirements
Operator requiranents will not change as. a consequence of this fluoride reduction
alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
PINE RIDGE COMPANY MOBILE HOME PARK
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPN)
Annual Cost Data
Capital
Operating
Consumer
flo. 1: Purchase
110. 2: Blending
—
33
—
$3 ,600
—
$25
—
$164.77
The superior method of effecting a solution to the fluoride problem in this commun-
ity is to purchase water from the Berkeley County Regional Water and Sewer Author-
ity. As of this writing, preliminary planning steps have been undertaken by that
authority to evaluate the feasibility of constructing a regional water system. We
hereby recommend that no action be taken on this system until a firm decision
relative to the establishment of a regional system is made. If that decision is
unfavorable, Alternative No. 2 should be implemented.
-6—
-------
REFERENCES
South Carolina Department of Health & Environmental Control, “Staff Study for
Pine Ridge Company, Berkeley County”, May 2, 1978.
-7-
-------
INTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Jater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcernent responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Plantersville Water System. In addition
to addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUND
EXISTING CONDITIONS
The Rlantersville water system has one well which is pumped at 150 GPM is
thought to have screens located below a depth of 475 feet, and has a fluoride
concentration of approximately 5.0 mg/i. 2 The water system has a 75,000 gallon
elevated tank 1 for water storage. The system presently serves approximately
240 residential connections which used anproxinately 60,000 GPO as an average
during 1979.1
FUTURE CO 1DITIOUS
1
During discussions with Mr. Bob Barker, who was at that time Director of the
Georgetown County ‘Iater & Sewer Authority (GCWSA), he indicated that a reason-
able assumption of the growth might be to expect 75 additional connections by
1990 and 50 more by the year 2000. Using the present average water consumption
rate of 250 GPD per connection, the future water demand would be 78,750 GPD by
1990 and 91,250 GPD by the year 2000. If it is assumed that the peak day water
demand will be 180% of the average day water use, 3 the water demand would be
141,750 (PD by 1990 and 164,250 PD by the year 2000. !lith those demands, the
desirable minimum pumping rates would be 147.7 GPM for 1990 and 171.1 GP 4 for
the year 2000, which would allow the estimated peak day water demand to be
pumped in 16 hours. Since the present well capacity is just slightly greater
than the predicted minimum pumping rate for 1990, a design well yield of 150 GPM
has been selected for this study.
With 315 water service connections estimated for the year 1990, Ameen’s method 4
for predicting instantaneous water demand on the supply system would predict the
—2—
-------
demand to be 363.8 GPM. Using the 150 GPM well yield, Ameen’s method 4 predicts
that the 75,000 gallon elevateci water storage tank will be more than adequate
to meet the instantaneous water supply demand of 364 CPM.
WATER STORAGE QUANTITY VERIF.ICATIOfl
Given:
1. 315 residential connections assumed as design condition.
2. Yield of new well is assumed to be 150 GPM
3. Existing elevated tank size is 75,000 gallons.
4. Peak demand, tank demand, and calculation procedures are as recornended
by Joseph S. Aneen in his book entitled “Cornunity Water Systems” on
pages 50 through 55.
Calculations:
1. 315 residences x 1.155 GPM/resd. = 363.8 GPI1.
2. 364 GPN1 - 150 GPM well yield = 214 GPM tank demand.
3. 214 GPM x 20 minute demand = 4,280 gallons of stored water needed.
4. Existing tank size is 75,000 gallons; therefore, tank is more than adequate.
—3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viabl-e fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desirabil-
i ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL NEW WELL(S)
Method
This alternative would involve the drilling of a new well or wells to replace or
blend with the existing high fluoride well. Since the blend ratio has been esti-
mated to be 3.0 gallons of low fluoride (0.2 mg/l) water for each gallon of the
existing deep well water to achieve a 1.4 mg/i blended fluoride concentration,
-4-
-------
it appears more practical for cost estimating purposes to assume that the
construction of a replacement well or wells will be required.
It should be noted that the alternative is heavily dependent upon the quantity
and quality of shallower water zones, bath of which are unknown. Therefore, for
this to be a viable solution, a test and water zone sampling well must be drilled
and sufficient, satisfactory water located. Once located, a production well
could be completed and tested. For this alternative it will be assumed that two
wells, one with an iron sequestering system, will be required to achieve the 150
GPM yield desired.
Cost Estimate
• Capital cost estimate for project design and construction $55,000
• Annual added debt service assuming 12% loan for 30 years $ 6,828
• Annual added operation cost using 1979 water use $ 300
• Total estimated added annual cost $ 7,128
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendum, rate structure studies,
funding procurement, etc.
Operator Regui rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: PURCHASE WATER FROM BROWN’S FERRY SYSTEM
Method
This alternative would involve the purchase of water from either Brown’s Ferry or
—5—
-------
Georgetown Rural water systems. The Plantersville system is already connected to
both systems and has in the past sold water to Brown’s Ferry. Therefore, no
construction would be required, except the reorientation of the meter between the
Plantersville and Brown’s Ferry systems. A phone conversation with a Georgetown
Rural representative revealed that effective April 1, 1980-, their bulk water
rate will increase from $0.30 to $0.45/lOGO gallons of water. Therefore, for
this report it has been assumed that purchase of water from Brown’s Ferry would
be less expensive.
Brownrs Ferry is in the process of completing a second well which, assuming the
quantity and quality of the water are acceptable, would give Brown’s Ferry con-
siderable extra capacity and certainly make sale of water to GCWSA desirable for
Brown’s Ferry. In the past, Brown’s Ferry has purchased water from GCWSA for
$0.30/bOO gallons. However, this appears to be too low a rate to expect, con-
sidering the current inflation rate. Therefore, for this report, $0.40/bOO
gallons has been chosen as being closer to what could actually be negotiated with
Brown’s Ferry.
Cost Estimate
To the writer’s knowledge, the only capital cost which might be required in imple-
menting this alternative would be the reorientation, or possibly, installation of
a master water meter. This cost is considered to be negligible and is not included
as a significant factor in the cost estimate.
• Added annual water cost, deleting power cost $7,973
rmpl ementa ti on
It has been estimated that the time required to achieve an acceptable agreement
between GCWSA and Brown’s Ferry concerning the method, rate, etc. of purchasing
water might take from 6 to 12 months.
-6-
-------
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
PLANTERSVI LLE
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPII)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: New Well(s)
No. 2: Purchase
Water
150
N/A
$6 828
—0—
$ 300
$7,973
$29.70
$33.22
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Presum-
inq that the increased annual cost will be amortized uniformly over the existing
consumer population, the annual incremental increase was calculated to be $29.70
per consumer ($2.48/month).
—7—
-------
RE FERE 1CES
1 Meeting and discussion with Bob Barker, Director of GCWSA, January 23 and 24,
1980.
Water Analysis, Sampling Location: Plantersvilie Comm., Sample #P 2059
DWCH — 609, dated February 15, 1979, F = 5.0 mg/i.
3 Clark, J. W., et al., book entitled Water Supply and Pollution Control , page 35,
1971, International Textbook Company, Scranton, Pa.
4 Ameen, Joseph S., book entitled Community Water Systems , pages 50 through 55,
1971, Technical Proceedings, Post Office Box 5041, High Point, North Carolina.
5 lelephone communication with Georgetown Rural Community water system representa-
tive, March 17, 1980.
6 lelephone communication with Brown’s Ferry representative, March 17, 1930.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
PLATT WATER COMPANY
HORRY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
INTRODUCTION.
BACKGROUND
Consumers
tIATER SUPPLY REQUIRE IEMTS
Current Demand
Projected Demand
Current and Projected Supply Requirements
EXISTING SUPPLY
FLUORIDE REDUCTION
Al t ative No. I: Blending
(,c.
tion
O”?tor’ R qui:’ernents
Alt e o. 2: Treatment
Implernen ation
Operator Requirements
Alternative No. 3: Regional System
Method
Cost
Implementation
Operator Requirements
Summary
REFERENCES
APPEFIDI CES
Regional Water System
Fluoride Treatment
TABLE OF CONTENTS
Page
1
2
2
2
3
3
4
6
-V
/
7
7
8
8
8
9
9
9
9
11
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcenient responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
50 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Platt Water Company. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
CON SUMERS
The water syst ii serving the Platt Water Company provided service to 450 consumers,
approximately 1575 people, as of February, 1978.1
In lieu of actual planning data, which is not readily available, an annual growth
rate of 10% will be assumed in ensuing sections of this report.
WATER SUPPLY REQUIREMENTS
Current Demand
The average daily water usage for calendar 1979 was 85,000 gallons) That trans-
lates to an average of 188 GPD/connection. Maximum average daily demand was con-
sidered to be approximately 180% of average daily usage. 2 Accordingly, the current
water demand placed on the system has been established as follows:
• Average Daily Demand 85,000 Gallons
o Maximum Daily Demand 153,000 Gallons
Projected Demand
Utilizing the previously assumed 10% annual growth rate in consumer population,
projected water demand has been estimated and is presented in the following table.
PLAIT WATER CO iPANY
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
85,000
137,000
221 ,000
153,000
247,000
398,000
-2-
-------
Current and Projected Supply Requirements
The below listed supply requirements were calculated utilizing a regulatory de-
sign criterion requiring that the well or wells be capable of meeting the maximum
daily demand in a 16-hour operating period.
• 1980 - 159 GPM,
• 1985 - 257 GPM,
• 1990 - 415 GPM,
EXISTING SUPPLY
The existing water supply consists of one deep well having a rated capacity of 200
GPM. Based upon the present requirement of 159 GPM, the existing production capa-
bility is adequate. It is noted, however, that water produced by the existing well
contains 4.0 mg/l fluoride which exceeds the limit of 1.6 mg/i established by law. 3
-3—
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified three viable fluoride reduction
alternatives for the Platt Water Company. Each alternative was subsequently
evaluated to determine the most practical and least expensive method of effect-
ing a solution to the fluoride problem. The ensuing paragraphs of this report
document the results of the evaluations and rank th2 alternatives in their order
of desirability.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 plannlng-lev2l cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operation 1 during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a prcper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: BLENDING
Method
Fluoride reduction can be achieved by drilling a series of shallow wells and blend-
ing their yield with that of the existing deep well. Assuming a fluoride concen-
tration of 0.1 mg/l in the proposed shallow wells, a shallow/deep mix of 2.0 GPM/
1.0 GPM will result in a blend having a fluoride concentration of 1.4 mg/l. Based
-4-
-------
upon that blend and the 1985 projected supply requirement, this alternative will
address the development of 180 GPM in shal1ow well capacity. Lacking accurate
data on the quantity of shallow ground water available in the Platt Water Company
area, quantity was conservatively estimated at 60 GPM per well, requiring con-
struction of three wells.
The success of blending is dependent upon control of the flow from the deep well.
With a shallow well yield of 180 GPM, the deep well pump should be throttled back
from 200 GPfi to 90 GPM. It should be noted that the adaptability of the existing
deep well pump to function in a throttled mode of operation is questionable. It
is beyond the limited scope of this study to fully evaluate the effect of the sig-
nificantly reduced pump output. The reader is therefore cautioned that it may
become necessary to modify or replace the existing unit to consistently maintain
flow rates less than 100 GPM.
Recognizing that the above-described blending process dictates a shift from deep
well water to a blend of predominantly shallow well water, the nuisance problems
associated with iron in the water supply must be considered. The existing shallow
wells may contain as much as 1.0 mg/l iron. At that concentration, aesthetic
problems, such as staining of plumbing fixtures, should be expected. Lacking
actual quality data on the shallow aquifer, it was assumed that the iron could be
sequestered and then diluted sufficiently to preclude the occurrence of iron
related nuisance problems. Feeding a solution of polyphosphates (chemical) to the
shallow well will provide an economical means of controlling red water. The chem-
ical is purchased dry in 50 or 100 pound bags and mixed with water to form a
solution. The mixture is then injected into the system by a small pump.
-5-
-------
One additional consideration is disinfection. Shallow wells are generally more
susceptible to bacterial contamination than are deep wells. Consequently, the
chlorinated blend of well water should be detained in a pressure contact tank
for 30 minutes prior to being discharged to the system.
A schematic drawing of the proposed water supply additions is presented in
Figure 1.
1. A complete list of the facilities recomended is as follows:
• Three shallow wells each having a capacity of 60 GPM.
• One equipment building to house chemical feed equipment.
o One 10,000 gallon pressurized chlorine contact tank.
o One concrete valve pit constructed at the intersection of the deep and
shallow t ei1 lines. The pit should contain meters arid valves on both
supply lines.
o Polypi osphate mixing and feed facilities. The concept presented herein
uti i:es a single chemical feed point in the common main leading from the
shallow wells. However, it should be noted that iron must be in a soluble
form for sequestering to be effective, and that pumping and/or conveyance
may cause the iron to precipitate. Should that situation occur the chem-
ical feed point may have to be moved or iron treatment may become necessary.
Cost
The construction cost of Alternative No. 1 including engineering and project con-
tingency expenses has been estimated at $160,000. Annual costs are summarized
bel ow.
• Debt Service on a 30-Year Loan at 12% $19,862
• Chemical Cost 638
Total Estimated Annual Cost Increase $20,500
-6-
-------
L_ .i
H----’
PROPOSED
1 } - SHALLOW
WELL (3 REQ’D.)
LT I
__ I __ __
1 -101
L_J
PROPOSED
— —( H- EQU 1PMENT
BUILDING
j EXISTING DEEP WELL
•1
L
PROPOSED VALVE PIT
OPOSED PRESSURE CONTACT TANK
FIGURE 1
SCHEMATIC DIAGRAM OF PROPOSED
WATER SYSTEM ADDITIONS
AT
PLATT WATER COMPANY
-------
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished
within 24 months of completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
\ TERNATIV JC. 2: TREATMENT
e t hod
This aiternati’ie addresses t ’eatment of a portior of the flow frori the existing
200 GP 1 well ut 1izing activated alumina. The system would be sized to treat
5 GPM, th ‘emaininq 65 3PM would bypass treatment and be blended with the
‘ fiuoridated •;ater. A liquid waste stream from the treatment unit would he .is-
ciarged direc:i to the sanitary sewer.
See the Appendix entitled “Fluoride Treatment” for a description of the act 1 a . u
alumina process.
Cost
The construction cost of Alternative No. 2 including engineering and project con-
tingency expenses has been estimated at $350,000. Annual costs are summarized
below.
• Debt Service on a 30-Year Loan at 12% $43,449
• Operations and Maintenance 29,551
Total Estimated Annual Cost Increase $73,000
-7-
-------
Impi ementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
36 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written examina-
tion, in order to obtain an “A” operating license. Approximately 120 hours of
formal training should be adequate to upgrade operator skills to the level re-
quired by the proposed treatment system. The actual cost to the community for
this training is anticipated to be approximately $3,000 plus travel and living
expenses.
ALTERNATIVE 110. 3: REGIONAL SYSTEM
Me thod
This alternative addresses the construction of a major water treatment facility
on the Great Pee Dee River at Bucksport. Distribution mains would convey the
water in a westerly direction as far as Conway, in a southerly direction as far
as Pawley’s Island, and in a northerly direction as far as North Myrtle Beach.
Management and operation of the proposed system would be effected under a joint
agreement of all political subdivisons involved.
Each community system served would purchase water on a bulk basis for resale to
its consumers.
-8-
-------
See the Appendix entit’ed “Regional Water System” for a more complete descrip-
tion of the proposed facilities.
Co St
The estimated bulk purchase rate for water drawn from the proposed regional
system will be S2.95 per 1000 gallons. At the current average daily demand
of 85,000 gallons, the annual cost will be 9l,524.
Iniplernentati on
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative car be accomplished
within 60 mont is of completion o required referendums, rate structure studies,
funding procurement, etc.
Operator Reguireme ts
Operator’ requirements will not change as a consequence of this fluoride reduction
a 1 ternative.
SUMMARY
The alternatives which were evaluated curing the course of this study are summa-
rized in the following table.
PLATT WATER COMPANY
ALTERNATIVE SUMI1ARY
Alternative
Capacity
(GPI)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Treatment
No. 3: Regional
270
200
224
S19,362
S43,449
$82,664
S 638
$29,551
$ 8,860
S 45.56
$162.22
$203.39
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
-9-
-------
Construction of the primary alternative would result in the following water rate
increase.
• Existing monthly rate $13.45
• Estimated monthly increase 3.80
Adjusted Monthly Water Rate $17.25/consumer
-10-
-------
REFERENCES
1 Personal comunication, Mrs. Helen Ellington, Platt Water Company
2 Clark, J. W., et al., Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
3 South Carolina Department of Health and Environmental Control, Water Analysis
Report on laboratory sample #P10084211, November 27, 1974.
4 South Carolina Department of Health and Environmental Control, “Staff Study for
Platt Water Company, Horry County,” April 21, 1978.
—11—
-------
FLUORIDE REDUCTION
I N
PUBLIC WATER SUPPLY
OF
RED HILL WATER SYSTEM
GEORGETmIN COUNTY IATER AND SEWER AUTHORITY
GEORGETOWN COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Future Conditions 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Alternative No. 1: Drill New Well
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Purchase Water from Brown’s Ferry System
Method 5
Cost Estimate 6
Implementation 6
Operator Requirements 6
Summary. 6
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Red Hill Water System. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Red Hill water system has one well which is pumped at 125 GPM, 1 has screens
located between the depths of 880 and 990 feet, and has a fluoride concentration
of approximately 3.2 mg/i? The water system has a 60,000 gallon pressure tank 1
for water storage. The system presently serves approximately 40 residential
connections which used approximately 10,000 GPD as an average during 1979.1
FUTURE CONDITIONS
Discussion with Mr. Bob Barker, who was at that time Director of the Georgetown
County Water and Sewer Authority (GCIISA), revealed that the Red Hill system has
not grown very much since its completion nor did Mr. Barker expect it to grow very
much in the future. Mr. Barker indicated that a reasonable assumption of the
growth might be to expect 15 to 20 new connections within the next thirty years.
Therefore, it has been assumed that this system will have an additional 20 resi-
dential connections for the system sizing purposes of this report.
Uith 60 residential connections, J\meen’s method 3 predicts that the instantaneous
water demand on the supply system would be 60 resd. x 2.7 GPM/resd. = 162 GPM.
Peaking the average day water use of 250 GPD per residence by a factor of 1.8k,
the 60 residential connections are estimated to use 0.027 MGD. However, the
desirable minimum pumping rate would be 28 GPM, which would allow the estimated
peak day demand to be pumped in 16 hours. Using this pumping rate, Mieen’s
method 3 predicts that the 60,000 gallon pressure storage tank can meet the
instantaneous water supply demand of 162 GPM.
—2—
-------
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 60 residential connections assumed as design condition.
2. Yield of new well is assumed to be 28 GPM.
3. Existing pressure tank size is 60,000 gallons.
4. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Ameen in his book entitled “Community Water Systems” on pages 50
through 55.
Calculations:
1. 60 residences x 2.7 GPI ’1/resd. = 162 GPM.
2. 162 GPII - 28 GPM well yield = 134 GPM tank demand.
3. 134 GP 1 x 20 minute demand = 2680 gallons of stored water needed.
4. Mininurri pressure tank size = 2,680 x 4 = 10,720 qallons.
5. Existing tank size is 60,000 gallons; therefore, tank is adequate.
—3-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for this community. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desirabil-
ity.
Financial information prewnted in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated co isumer expense
reflects a present cay situation. In other words, ne assumpt on was msde that
thp alternative ‘qas con’ tr’ cted and became operational during the 1980 c.lendar
year. By .tilizing current data, comparison of the various alternatives is
placed in a ;roper rerspective with the community’s present fiscal position.
?ecognizinç t.haL the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital nd
ooerating costs with respect to anticipated construction schedules.
ALTER 1ATIVE NO. 1: DRILL NEW WELL
Met had
This alternative would involve the drilling of a new well to replace the existing
high fluoride well. Since it has been estimated that only 28 GPM will be needed
from a well, it appears more economical to construct a new well rather than blend
or treat the existing well.
-4—
-------
It should be noted that this alternative is heavily dependent upon the quantity
and quality of shallower ground water zones, both of which are unknown. There-
fore, for this to be a viable solution, a test and water zone sampling well must
be drilled and sufficient, satisfactory water located. Once located, a produc-
tion well could be completed and connected to the system. For cost estimating
purposes, it will be assumed that iron sequestering will be required. The exist-
ing well would have to be disconnected.
Cost Estimate
• Capital cost estimate for well design and construction $35,000
• Annual added debt service assuming 12% loan for 30 years $ 4,345
• Annual added operation cost using 1979 water use $ 100
• Total estimated added annual cost $ 4,445
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of implementing this alternative.
ALTERNATIVE NO. 2: PURCHASE WATER FROM BROWN’S FERRY SYSTEM
Method
This alternative would involve the installation of approximately 1.0 miles of six-
inch water main to connect the Red Hill system with the Brown’s Ferry system and
-5-
-------
the purchasing of water by GCWSA from the Brown’s Ferry owner. Brown’s Ferry is
in the process of completing a second well which, assuming the quantity and
quality of the water are acceptable, would give Brown’s Ferry considerable extra
capacity and certainly make sale of water to GCWSA desirable for Brown’s Ferry.
In the past, Brown’s Ferry has purchased water from GCWSA at a price of $0.30!
1000 gallons. 5 However, this appears to be too low a rate to expect, consid-
ering the recent inflation rate. Therefore, for this report, $0.40/1000 gallons
has been chosen as being closer to what could actually be negotiated with Brown’s
Ferry.
Cost Estimate
• Capital cost estimate for connection design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added water cost, deleting power costs $ 1,330
• Total estimated added annual cost $ 6,917
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
-6-
-------
RED HILL
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: New Well
No. 2: Purchase
Water
28
N/A
$4,345
$5,587
$ 100
$1,330
$111.13
$172.93
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community. Presum-
ing that the increased annual cost will be amortized unifomly over the existing
consumer population, the annual incremental increase was calculated to be $111.13
per consumer ($9.26/month).
—7—
-------
REFERENCES
‘Meeting and discussion with Bob Barker, Director of GCWSA, January 23 and 24,
1980.
2 DHEC Water Analysis, Sampling Point: Red lull Water District, Laboratory Sample
No. R 05058-1323, dated May 3, 1978,F = 3.2 mg/i.
3 Ameen, Joseph S., book entitled Community Water Systems , pages 50-55, 1971,
Technical Proceedings, Post Office Box 5041, High Point, North Carolina.
4 Clark, J. W., et al., book entitled Water Supply and Pollution Control , page 35,
1971, International Textbook Company, Scranton, Pa.
5 lelephone communication with Brown’s Ferry representative, March 17, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
ROCK BLUFF SUBDIVISION
WILLIAMSBURG COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Existing Conditions 2
Estimated Peak Water Demand 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 6
SUMMARY . 6
REFERENCES 7
-------
INTRODUCTION
Beginning on JUflE 24, 177, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Jater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 pjblic water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Rock Bluff Subdivision. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated at
1979 water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
The Rock Bluff water system has one well which is pumped at 75 GPM, has an iron
concentration of less than 0.1 mg/l, and has a fluoride concentration of from
1.65 to possibly 2.7 mg/i, depending on which water analysis 1 is accepted. The
South Carolina Department of Health and Environmental Control (DHEC) has indica-
ted that the well’s fluoride concentration is 1.7 mg/i in their Staff Study on
Fluoride. The water system has a 3,000 gallon pneumatic tank for water storage.
The system served approximately 65 people in 21 homes during 1979. Metered
water use of the residences during 1979 averaged 4210 GPD and was 4493 GPD during
the peak months. This subdivision has not grown at all during the last two years
and is not expected to grow in the near future.
ESTIMATED PEAK WATER DEMAND
If it is assumed that the peak day water demand is 180% of the average day
water use, 2 the water demand would be 7,578 GPD. With that demand, the
desirable minimum pumping rate would be 7.9 GP!1, which would allow the esti-
mated peak day water demand to be pumped in 16 hours. If Anieen’s method 3 for
predicting instantaneous water demand on the supply system is used, the esti-
mated demand would be 89.3 GPM. Without verification of a lower instantaneous
water demand, this demand is accepted as a condition of design. Using this
instantaneous water supply demand, I meen’s method 3 of checking pneumatic tank
size indicates that a well capacity of at least 51.8 GPM would be needed if the
existing 3,000 gallon tank is all the storage available. However, an additional
3,500 gallons of pneumatic tank capacity would allow the use of an 8 GPM well,
-2-
-------
which is estimated to be sufficient to meet the peak day demand.
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 21 residential connections assumed as design condition.
2. Existing pneumatic tank size is 3,000 gallons.
3. Peak demand, tank demand, and calculation procedures are as recommended by
Joseph S. Ameen in his book entitled “Comunity Water Systems” on pages 50
through 55.
Calculations:
1. 21 residences x 4.25 GPM/resd. = 89.3 GPM.
2. Usable pneumatic tank volume = 3000 4 = 750 gallons.
3. Tank contribution for 20 minutes = 750 20 minutes = 37.5 GPM.
4. Minimum new well size to meet instantaneous supply demand = 89.3 GPM -
37.5 GPM = 51.8 GPM.
5. Minimum pneumatic tank capacity with a 8 GPM well = (89.3 GPM - 8 GPM) x
20 minutes x 4 = 6,504 gallons.
6. Additional pneumatic tank capacity needed = 6,504 gal. - 3,000 gallons =
3,504 gallons. Use 3,500 gallon tank.
-3-
-------
FLUORIDE REDUCTI ON
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is reconinended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
METHOD
The viable alternatives for this system appear to be quite limited. One possible
alternative would be to connect to the City of Kingstree’s water system. How-
ever, Kingstree’s water system is approximately 3.1 miles from Rock Bluff Subdi-
vision. Utilizing an estimated construction cost of $6.00 per foot for a 6”
diameter PVC pipe installation, the cost would be over $98,000. Other costs
would include design, a master meter installation, drive and roadway repairs,
highway borings, etc. Due to the high cost per residence, this alternative has
been eliminated.
The only viable alternative for this system appears to be the drilling of a new
well to tap a more acceptable water source. Blending with the existing well water
is possible since the existing well has a fluoride concentration only slightly
above the legal limit of 1.6 mg/i. If the existing well has a fluoride concentration
-4-
-------
of only 1.7 mg/i as reported in one analysis, then it would take only 19 GPM of
low fluoride (0.2 mg/i or less) well water to blend with the existing 75 GPM
well to achieve a blended fluoride concentration of approximately 1.4 mg/i.
If the existing well’s fluoride concentration is actually 2.7 mg/i, as another
analysis indicated, then 80 GPM of low fluoride water would be required.
Since it has been estimated that only 8 GPM is needed to meet the peak day water
demand and the blend quantity needed is uncertain, it will be assumed for this
alternative that a new well of 8 GPM will be installed. Excessive iron could
be a problem which would necessitate installing iron removal treatment equipment.
However, it appears reasonable to assume that 8 GPM of relatively low iron,
low fluoride water can be located. Therefore, for cost estimating purposes,
it will be assumed that iron sequestering treatment will be required. In addi-
tion to the above, this solution would require the installation of chlorine
equipment and a 3,500 gallon pneumatic tank.
COST ESTIFIATE
• Capital cost estimate for well design and construction $45,000
• Annual added debt service assuming 12% loan for 30 years $ 5,587
• Annual added operation cost using 1979 average demand $ 46
• Total estimated added annual cost $ 5,633
IMPLEMENTATION
It has been estimated that design, securing of approval, advertisement, contract
execution, and construction on this alternative can be accomplished within 24
months of the completion of required referendums, rate structure studies, fund-
ing procurement, etc.
-5-
-------
OPERATOR REQUIREMENTS
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
Based upon available information, the most practical and least expensive method
of solving the fluoride problem for the Rock Bluff Subdivision appears to be to
construct the well project described above. Presuming that the increased annual
cost will be amortized uniformly over the existing customer population, the
annual incremental increase is calculated to be $268.24 per consumer ( 22.35/
month).
—6—
-------
REFERENCES
1 DHEC Analysis Reports identified as follows:
(a) Station Code 545001, Laboratory Sample No. P102760363, DWCH—128, dated
October 18, 1976.
(b) Rock Bluff Subdivision, Laboratory Sample No. R06148-l573, dated June 13,
1978.
Cc) Station Code 545001, Laboratory Sample No. P1722, DWCH-436, dated
January 15, 1976.
(d) Station Code 455001, Laboratory Sample No. P02069-1875, dated February 5,
1979.
(e) Station Code 455001, Laboratory Sample No. P-01259-1757, dated January 24,
1979.
(f) Rock Bluff Subdivision, Laboratory Sample No. P01319-1813, dated
January 29, 1979.
2 Clark, 3. W., et al. Water Supply and Pollution Control , page 35, 1971,
International Textbook Company, Scranton, Pennsylvania.
3 Ameen, Joseph S., Community Water Systems , pages 50-55, 1971, Technical
Proceedings, Post Office Box 5041, High Point, North Carolina.
—7—
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
ROSE HILL WATER SYSTEM
GEORGETOWN COUNTY WATER AND SEWER AUTHORITY
GEORGETOWN COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . 1
BACKGROUND
Existing Conditions . 2
Future Conditions 2
Water Storage Quantity Verification 3
FLUORIDE REDUCTION
Alternative No. 1: Drill New Well
Method 4
Cost Estimate 5
Implementation 5
Operator Requirements 5
Alternative No. 2: Purchase Water from Brown’s Ferry System
Method 5
Cost Estimate 6
Implementation 6
Operator Requirements 6
Sumary 6
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcernent responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(Sc DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
e f fo r t.
rn January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Rose Hill Water System. In addition to
addressing the conceptual solution from a technical standpoint, planning—level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
EXISTING CONDITIONS
1
The Rose Hill water system has one well which is pumped at 125 GPM, has screens
located between the depths of 769 and 918 feet, and has a fluoride concentration
of approximately 4.0 mg/l. 2 The water system has a 20,000 gallon pressure tank 1
for water storage. The system presently serves approximately 42 residential
1
connections which used approximately 11,000 GPO as an average during 1979.
FUTURE CONDITIONS
1
Discussion with Mr. Bob Barker, who was at that time Director of the Georgetown
County Water and Sewer Authority (GCWSA), revealed that the Rose Hill system has
not grown very much since its completion nor did Mr. Barker expect it to grow
very much in the future. Mr. Barker indicated that a reasonable assumption of
the growth might be to expect 18 to 23 new corrections within the next thirty
years. Therefore, it has been assumed that this system will have an additional
23 residential connections for the system sizing purposes of this report.
With 65 residential connections, Ameen’s method predicts that the instantaneous
water demand on the supply system would be 65 resd. x 2.6 GPM/resd. 169 GPM.
4
Peaking the average day water use of 262 GPD per residence by a factor of 1 .8
the 65 residential connections are estimated to use 0.0307 MGD. However, the
desirable minirium pumping rate would be 32 GPPI which would allow the peak day
demand to be pumped in 16 hours. Using this pumping rate, Ameen’s method 3 pre-
dicts that the 20,000 gallon pressure storage tank can r, eet the instantaneous
water supply demand of 169 GPM.
-2-
-------
WATER STORAGE QUANTITY VERIFICATION
Given:
1. 65 residential connections assumed as design condition.
2. Yield of new well is assumed to be 32 GPM.
3. Existing pressure tank size is 20,000 gallons.
4. Peak demand, tank demand, and calculation procedures are as recomended
by Joseph S. Ameen in his book entitled “Community Water Systems” on
Pages 50 through 55.
Calculations:
1. 65 residences x 2.6 GPM = 169 GPM.
2. 169 GPM - 32 GPM well yield = 137 GPM tank demand.
3. 137 GPM x 20 minute demand = 2740 gallons of stored water needed.
4. Minimum pressure tank size = 2740 x 4 = 10,960 gallons.
5. Existing tank size is 20,000 gallons; therefore, tank is adequate.
—3-
-------
FLUORIDE REDUCTION
Prelininary investigative efforts identified two viable fluoride reduction alter-
natives for this coimiunity. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desirabil-
i ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
ALTERNATIVE NO. 1: DRILL NEW WELL
Method
This alternative would involve the drilling of a new well to replace the existing
high fluoride well. Since it has been estimated that only 32 GPII will be needed
from a well, it appears more economical to construct a new well rather than blend
or treat the existing well.
-4-
-------
It should be noted that this alternative is heavily dependent upon the quantity
and quality of shallower ground water zones, both of which are unknown. There-
fore, for this to be a viable solution, a test and water zone sampling well must
be drilled and sufficient, satisfactory water located. Once located, a produc-
tion well could be completed and connected to the system. For cost estimating
purposes, it will be assumed that iron sequestering will be required. The exist-
ing well would have to be disconnected.
Cost Estimate
• Capital cost estimate for well design and construction $35,000
• Annual added debt service assuming 12% loan for 30 years $ 4,345
• Annual added operation cost using 1979 water use $ 110
• Total estimated added annual cost $ 4,455
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24 months of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requi rements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
ALTERNATIVE NO. 2: PURCHASE WATER FROM BROWN’S FERRY SYSTEM
Method
This alternative would involve the installation of approximately 0.9 miles of six-
inch water main to connect the Rose Hill system with the Brown’s Ferry system and
-5-
-------
the purchasing of water by GCWSA from the Brown’s Ferry owners. Brown’s Ferry
is in the process of completing a second well which, assuming the quantity and
quality of the water are acceptable, would give Brown’s Ferry considerable
extra capacity and certainly make sale of water to GCWSA desirable for Brown’s
Ferry. In the past, Brown’s Ferry has purchased water from GCWSA at a price of
$0.30/bOO gallons. 5 However, this appears to be too low a rate to expect, con-
sidering the current inflation rate. Therefore, for this report, $0.40/bOO
gallons has been chosen as being closer to what could actually be negotiated with
Brown’s Ferry.
Cost Estimate
• Capital cost estimate for connection design and construction $42,000
• Annual added debt service assuming 12% loan for 30 years $ 5,214
• Annual added water cost, deleting power cost $ 1 ,462
• Total estimated added annual cost $ 6,676
Implementation
It has been estimated that design, securing of permits and approvals, advertise-
ment, contract execution, and construction of this alternative can be accomplished
within 24rnonths of the completion of required referendums, rate structure studies,
funding procurement, etc.
Operator Requirements
Operator requirements for this system are not expected to change as a consequence
of this alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
-6-
-------
ROSE HILL
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: New Well
No. 2: Purchase
Water
32
N/A
$4,345
$5,214
$ 110
$l ,462
$106.07
$158.95
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this comunity. Presum-
ing that the increased annual cost will be amortized uniformly over the existing
consumer population, the annual incremental increase was calculated to be
$106.07 per consumer ($8.84/month).
-7-
-------
REFERENCES
1 Meeting and discussion with Bob Barker, Director of GCWSA, January 23 and 24,
1980.
2 DHEC Water Analysis, Sampling Point: Rose Hill W/D, Laboratory Sample No.
R 05058-1322, dated May 3, 1978, F = 4.0 mg/i.
3 pimeen, Joseph S., book entitled Community Water Systems , pages 50-55, 1971
Technical Proceedings, Post Office Box 5041, High Point, North Carolina.
4 Clark, J. W., et al., book entitled Water Supply and Pollution Control , page 35,
1971, International Textbook Company, Scranton, Pa.
5 Telephone communication with Brown’s Ferry representative, March 17, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
SANGAREE SUBDIVISION
BERKELEY COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY AND AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION i
BACKGROUND
Consumers 2
Water Supply Requirements
Current Demand 2
Future Demand 2
Existing Supply 3
Current and Projected Supply Requirements 3
FLUORIDE REDUCTION
Short Term Solution
Blending . 4
Long Term Solutions
Alternative No. 1: Regional System
Method 6
Alternative No. 2: Water Purchase
Method 6
Cost 6
Implementation 7
Operator Requirements 7
Sumary 7
REFERENCES 8
-------
I NTRODUCTI ON
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said star dards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Sangaree Subdivision. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs
are presented in 1980 dollars and that all operating expenses were calculated
at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
The water system serving Sangaree Subdivision provided service to 800 consumers,
approximately 2,800 people, as of June, 1979.1 The system is owned and operated
by the Berkeley County Regional Water and Sewer Authority (BCRW&SA). Tramway,
an adjacent subdivision which is also owned by BCRW&SA, is interconnected with
the Sangaree Facilities and presently serves 15 consumers.
WATER SUPPLY REQUIREMENTS
Current Demand
Accurate data on actual water use in these communities is not readily available.
Consequently, system averages developed from records of similar communities were
utilized as a basis for establishing assumed values which will be utilized in
ensuing sections of this report. An average daily usage of 200 gallons per con-
nection and a maximum daily demand factor of l80%2 were used to establish the
following system demand data:
• Average Daily Demand 163,000 Gallons
• Maximum Daily Demand 293,400 Gallons
Future Demand
Ultimate development of Sangaree and Tramway Subdivisions will result in a r 1 iaxi—
mum consumer population of 4,300, approximately 15,050 people. Utilizing the
data discussed above, future system demand was calculated and is listed below.
• Average Daily Demand 860,000 Gallons
• liaximum Daily Demand 1,548,000 Gallons
-2-
-------
Existing Supply
The existing supply consists of three wells, two in Sangaree and one in Tramway.
The capacity and fluoride concentration of each well is tabulated in the follow-
ing table.
SANGAREE AND TRAMWAY SUBDIVISION
WATER WELL DATA
Designation Capacity Fluoride
(GPM) Concentration
1 3
Sangaree #1 250 2.0 mg/i
Sangaree #2 1401 2.8 mg/i 4
1 5
Tramway #1 137 1.3 mg/i
Current and Projected Supply Requirements
The below listed supply requirements were calculated utilizing a regulatory
criterion requiring that the well or wells be capable of meeting the maximum
daily demand in a 16-hour operating period. Those values are as follows:
• Current - 305 6PM
• Future (ultimate) — 1615 GPM
—3—
-------
FLUORIDE REDUCTION
Fluoride reduction in this comunity falls into two categories — short term and
long term. Blending the yield from the Tramway well with a portion of the
Sangaree supply will provide an immediate, but short-lived, solution to the
problem. The two subdivisions are growing rapidly and should be expected to
place an increasingly heavy demand on the combined supply for the forseeable
future. Accordingly, several long-term solutions that have the potential of
meeting the anticipated future demand were evaluated.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and becane operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position. Rec-
ognizing that the cost data is presented in 1980 dollars, it is recommended that
initial planning of any alternative should include a reevaluation of capital and
operating costs with respect to anticipated construction schedules.
SHORT TERM SOLUTION
Blending
Blending the Tramway and Sangaree water supplies has recently been implemented.
The interconnection between the two subdivisions was accomplished by constructing
a 10-inch PVC line between the extremities of the two distribution systems. The
approximate length of the connector is 6000 linear feet. One directional flow
from Tramway to Sangaree is maintained by continuous operation of the Tramway well.
-4-
-------
In that mode of operation, approximately 200,000 gallons of low fluoride
(1.3 mg F71) water is produced each day. Utilizing water from Sangaree #1
(2.0 mg F-/i) as the blending source, a ratio of 1.0 part Tramway: 0.75 part
Sangaree will produce a combined flow of 235 GPM having a fluoride concentra-
tion of 1.6 mg/l. To achieve the desired mix, the Sangaree well must be
throttled from 250 GPM to 100 GPF 1. During a 24-hour operating period, the max-
imum available blended capacity of this system is 338,400 gallons.
Based upon the current estimated peak day demand of 293,400 gallons, this
water system can achieve imediate compliance with the fluoride standard by
making several changes in the operation of the facilities . Those changes should
consist of the following:
• Close the necessary valves to ensure a positive one-way flow from Tramway
to the base of the elevated storage tank in Sangaree;
• Make piping modifications at the elevated tank site to ensure a positive
blend of the two supplies;
• Take Sangaree well No. 2 out of service, and;
• Throttle Sangaree tIell No. 1 from 250 GPM to 100 GPM.
It should be noted that the total capacity of this supply must be reduced by
40% to achieve a blend with an acceptable fluoride concentration. Accordingly,
meeting the estimated peak day demand will require that the in-service wells be
pumped for 21 hours which exceeds the state design criteria of 16 hours. Rec-
ognizing that this is an existing condition, it was assumed that regulatory
approval of a variance from design criteria could be obtained.
-5-
-------
LONG TERM SOLUTIONS
Alternative No. 1: Regional System
Method . This alternative requires the abandonment of the existing supply and
connection to a proposed regional water system. The feasibility of construct-
ing that system is being studied by the Berkeley County Regional Water and Sewer
Authority; therefore, no definitive information relative to the availability
or cost of water service is presently obtainable.
Alternative No. 2: Water Purchase
Method . This alternative requires that the existing ground water supply be
abandoned and the Sangaree system be connected to the facilities owned by the
Charleston Commissioner of Public Works (CCPW). The connection would be effec-
ted by constructing a water main from the intersection of Royal Road with
Frontage Road to the intersection of Trestlewood Dr ive with Woodbridge Boule-
vard. The installation would require the construction of approximately 4500
linear feet of 12-inch line and a 10” meter vault.
Cost . The estimated construction cost of this alternative is $96,000. That
estimate is based on a pipeline installation cost of $20.00 per L.F. and a meter
charge of $6,000.6 The increased annual costs are summarized below.
• Debt service on a 30-year loan @ 12% $11,520
• Water purchase expense 30,000
Subtotal $41 ,520
• Less power cost (abandoned wells) 2,520
Total Estimated Annual Cost Increase $39,000
-6-
-------
Implementation . Design, securing permits and approvals, solicitation of pro-
posals, contract negotiation and award, and construction of this alternative
can be accomplished within 24 months of completion of required referendums,
rate structure studies, funding procurement, etc.
Operator Requirements will not change as a consequence of this fluoride reduc-
tion alternative.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
SANGAREE AND TRAMWAY SUBDIVISIONS
ALTERNATIVE SUMMARY
Alternative Capacity Annual Cost Data
(GPM) Capital Operating Consumer
No. 1: Regional
No. 2: Purchase $11,520 $27,480 $47.85
The superior method of effecting a solution to the fluoride problem in this com-
munity is to construct the proposed regional system. As of this writing, pre-
liminary planning steps have been undertaken by BCRW&SA to evaluate the feasibil-
ity of constructing that water system. We hereby recommend that no action be
taken on this water supply until a firm decision relative to the establishment
of a regional system is made. If that decision is unfavorable, Alternative No. 2
should be implemented. That course of action would result in the following
water rate increase.
• Existing monthly rate 7 $12.76
• Estimated monthly increase 3.99
Adjusted monthly water rate $16,75/consumer
-7-
-------
REFERENCES
‘Personal communication, Arthur Bryngelson, Berkeley County Regional Water and
Sewer Authority, June 11, 1980.
2 Clark, J. W., et al. Water Supply and Pollution Control , 1971, International
Textbook Company, Scranton, Pennsylvania.
3 South Carolina Department of Health and Environmental Control, Water Analysis
Report on Sample No. P011470612, February 3, 1977.
4 South Carolina Department of Health and Environmental Control, Water Analysis
Report on Sample No. P011470613, February 3, 1977.
5 personal communication, Arthur Bryngelson, Berkeley County Water and Sewer
Authority, January 7, 1980.
6 Personal communication, Steve Kinard, Charleston Commissioners of Public Uorks,
June 12, 1980.
7 South Carolina Department of Health and Environmental Control, “Staff Study
for Sangaree Subdivision, Berkeley County”, March 30, 1978.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
SOUTH TRAIIQUIL ACRES SUBDIVISION
DORCHESTER COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMP1 NY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION I
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Supply Requirements 2
FLUORIDE REDUCTION
Method 5
Purchasing Variation 5
Blending Variation 6
Cost 7
Implementation 7
Operator Requirements 7
REFERENCES 8
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC OHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of South Tranquil Acres Subdivision. In
addition to addressing the conceptual solution from a technical standpoint,
planning-level cost estimates are also presented. It should be noted that all
capital costs are presented in 1980 dollars and that all operating expenses were
calculated at 1979 water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
South Tranquil Acres is an established residential subdivision. It is
located in Dorchester County and lies to the south of the Town of Summerville.
The water system serving South Tranquil Acres provided water to 100 consumers,
1
approximately 350 people, as of April, 1978.
Most building lots in the subdivision are occupied; therefore, the population
is expected to remain static.
WATER SUPPLY REQUIPEMENTS
Current Demand
Accurate data on actual water use in this community is not readily available.
Consequently, system averages developed from records of similar communities
were utilized as a basis for establishing assumed values which will be utilized
in ensuing sections of this report. An average daily usage of 160 gallons per
connection and a maximum daily demand factor of 180% were used to establish
the following system demand data:
• Average Daily Demand 16,000 gallons
• Maximum Daily Demand 28,800 gallons
Supply Requirement
The most practical alternative for reducing the fluoride concentration in this
water supply is to purchase water from the Town of Summerville. The system
-2-
-------
owner has expressed a preference for purchasino enough water from the Town
to blend with the existing groundwater supply. Another variation of the
purchasing alternative is to abandon the existing wells and obtain the
entire supply from Sumerville. Accordingly, the economics of both variations
were analyzed.
Supply Requirements for the-Complete Purchase’Va -riation were assumed to be
the average daily flow during a period of maximuri demand. That requirement
was computed as follows:
( 28,800 gal ) = 20 GPM
(24 hrs)(60 min/hr)
Supply Requirements for the Blendin j Variation were calculated based upon the
following list of assumptions and data:
• The well which is located along Ladson Road will be utilized as the
groundwater supply due to its proxiriity with the Town of Summerville’s
system.
• The well which is located at the intersection of Lamie Drive and Harrison
Road will be abandoned. This capacity will be replaced by water pur-
chased from the Town.
• The water purchased from Sumervilie will contain 0.2 mg/i fluoride.
• Water drawn from the existing well has a fluoride concentration of 3.0
2
mg/i.
• A fluoride concentration of 1.4 mg/i can be achieved by maintaining the
Summerville flow at 1.33 times the existinci well flow.
1
O The capacity of the existing well is 60 GPM. The blend will require that
80 GPM be obtained from the Town.
-3-
-------
• The instantaneous deriand for a system with 100 homes connected to it
3
is 2 GPM/connection.
Computation of supply requirements for the blending variation was made as
follows:
• Total Instantaneous Demand
(2 GPM)(100 homes) = 200 GPM
• Instantaneous Supply Demand
(200 GPM)(20 mm) = 4,000 Gallons
• Available Punping Capacity
(140 GPM)(20 mm) = 2,800 Gallons
• Pneumatic Storage Requirement
4000 Gal - 2800 Gal
*0.25 = 4,800 Gallons
As calculated above, the supply requirerient of the blend variation is 140 GPM
with a pneumatic storage capacity of 4,800 gallons .
* Pneumatic tanks ideally satisfy a given water storage requirerient by utilizinq
25% of the available tank volume for water storage and 75% for air storage.
-4-
-------
FLUORIDE REDUCTION
I 1 IETHOD
As previously discussed, the most practical method of effecting a fluoride
reduction in the water supply of South Tranquil Acres is to purchase water
from the Town of Summerville. Two variations of a purchasing alternative
were evaluated. One addresses abandonment of the two existing wells and the
purchase of the entire supply from Summerville; the other requires the pur-
chase of approximately 6O of the supply from the Town and blending that
with the production of the Ladson Road well.
Purchasing Variation
The Town of Summerville presently has a distribution main in Ladson Road.
4
The estimated fee for a 2” metered connection is $1,200. Allowing another
$800 for piping changes at the well site brings the total estimated capital
cost to 2,OOO.
Annual costs for this systen were calculated as follows:
• Debt Service on a 30-Year Loan at 12% $ 248.28
• Water Purchase 4,051.72
Subtotal $4,300.00
5
• Less Power Cost 1,200.00
Total Annual Cost Increase $3,100.00
-5-
-------
Blending Variation
The metered connection to the Summerville system required by this variation
would also be a 211 and the connection fee is estimated to be 1,2OO.
To avoid the need for constant superintendence by a skilled operator, a system
utilizing a suction tank and booster pump was selected as the means to effect
blending in this community. The use of more sophisticated flow proportioning
equipment was disregarded in an effort to maintain the operation and main-
tenance requirements at existing levels. The facilities required are
schematically presented in Figure No. 1 and are more fully described in the
following list.
• Construct a 5,000 gallon suction tank on a concrete foundation. The
tank will be maintained full of Supimerville water by an automatic level
control valve.
• Install an 80 GPM booster pump which will run simultaneously with the
well pump. The pump will be fed by the suction tank described above
and will be piped into the inlet side of the pneumatic tank.
• The existing pneumatic tank may have to be replaced due to its obvious
lack of capacity. The cost of this work was, however, not included in
the estimates because it may not be required by the state.
The construction cost of the pumpina system including engineering, project con-
tingency expenses and the connection fee has been estimated at $21 ,200.
Annual costs for this system were calculated as follows:
-6-
-------
TO
DISTRIBUTION
SYSTEM
650 GAL.)
EXISTING
60 GPM WELL
/
/
\
‘ PROPOSED 5,000 GAL.
) SUCTION TANK
/
PROPOSED LEVEL
CONTROL VALVE
PROPOSED 2” METER
SUMMERVI LLE
WATER MAIN
ADS0NROAD: 1 ±±21 _
I PROPOSED 2” TAP
FIGURE 1
SCHEMATIC DIAGRAM OF PROPOSED
WATER SUPPLY PDDITIONS
AT
EXISTING PNEUMATIC
STORAGE TANK
(APPROXIMATE CAPACITY
PROPOSED
80 GPM BOOSTER PUMP
SOUTH TRANQUIL ACRES SUBDIVISION
-------
• Debt Service on a 30-Year Loan at 12% $2,631.76
• Water Purchase 2,568.24
• Pumping Cost (no change) - 0 -
Total Annual Cost Increase $5,200.00
COST
The additional incremental annual cost increase per consumer for the two varia-
tions of this alternative would be as follows:
• Purchase $31.00 ($2.58/month )
• Blend $52.00 ($4.33/month )
IMPLEIIEflTATIOFI
Subsequent to the completion of required referendums, rate structure studies,
funding procurement, etc., implementation can be achieved as follows:
• Purchase 18 months
• Blend 24 months
OPERATOR REQUIRE 1ENTS
Operator requirements for this system will not change as a consequence of fluoride
reduction in the water supply.
-7—
-------
RE FERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study
for Tranquil Acres Subdivision, Dorchester County, April 17, 1978.”
Carolina Department of Health and Environmental Control, Water Analysis
Report on Laboratory Sample tb. P07208-086, July 27, 1978.
3 joseph S. Ameen, “Community Water Systems”, 1971, Technical Proceedings, High
Point, North Carolina.
4 personal communication, Hr. Roy Winey, Town of Summerville, March 27, 1930.
5 Personal communication, Mrs. Wilkins, system owner, March 28, 1980.
-8-
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
THE TOWN OF STUCKEY
WILLIAFISBURG COUNTY, SOUTH CAROLINA
JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION . I
BACKGROUND
Consumers . 2
Water Supply Requirements
Current Demand 2
Projected Demand 3
Current and Projected Supply Requirements 3
Existing Supply 3
Proposed Facilities 4
FLUORIDE REDUCTION
Method 5
Cost 5
Implementation 6
Operator Requirements 6
REFERENCES 7
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking Water Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of the Town of Stuckey. In addition to
addressing the conceptual solution from a technical standpoint, planning-level
cost estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—1—
-------
BACKGROUND
CONSUMERS
The water system serving the Town of Stuckey provided water to 66 consumers
as of June, 1978.1 Present plans are to extend the system to serve 20
additional consumers. 2
Williamsburg County is expected to experience continued industrial growth
during the forseeable future. As a consequence of that growth, the con-
sumer population of the Stuckey water system can be expected to grow.
WATER SUPPLY REQUIREMENTS
Utilizing criteria developed by the Town’s consulting engineer, current and
projected water supply requirements were calculated as follows. 1
Current Demand
• People served
o Average Daily Demand (in gallons)
Domestic (344)(l0O)(l.5)
Fa mi rig
Industry
Total
• Maximum Daily Demand (in gallons)
Domestic (51,600)(l.5)
Farming
Industry
Total
= (66 + 20)(4) = 344
= 51 ,600
= 13,000
= - ‘0
= 64,600
= 77,400
= 13,000
= - 0-
90,400
-2-
-------
1995 Projected Demand
• Average Daily Demand (in gallons)
Domestic (600)(i00)(l.5)
Farming
Industry (100 GPM)(24 hrs)
(60 mm)
Total
• Maximum Daily Demand (in gallons)
Domestic (90,000)(.l .5)
Farming
Industry
Total
= 90,000
= 13,000
= 144,000
247,000
= 135,000
= 13,000
= 144,000
292,000
S
Projected
= 94 GPM
= 304 GPM
EXISTING SUPPLY
The existing water supply consists of one deep well having a rated capacity
of 150 GPM. Based upon the present requirement of 94 GPM, the existing
production capability is adequate. It is noted, however, that water pro-
duced by the existing well contains 2.3 mg/i fluoride which exceeds the
limit of 1.6 mg/i established by law. In addition to producing water which
does not meet the “National Interim Primary Drinking Water Standards”
(NIPDWS), the facilities have been in continuous service for approximately
15 years and may therefore require extensive maintenance.
Current and Projected Supply Requirements
• Current 90,400 nallons
( 16 hrs) .60 mm)
292,000 gallons
(16 hrs)(60 mm)
‘-3—
-------
PROPOSED FACILITIES
Being cognizant of the need for an expanded supply to meet future water
demands, the Town of Stuckey is planning the construction of water system
improvements. Said improvements are scheduled to include at least one new
200 GPM water well.
-------
FLUORIDE REDUCTION
METHOD
Proper construction of the proposed new well should provide a water supply
that complies with the fluoride limit established by the NIPDWS. The spec-
ifications for the new well should require selective testing of each water
bearing strata that is penetrated. Based upon the test results, screen
settings for the production well should be selected to accomplish an “in-well”
blend that will yield an acceptable fluoride level. Assuming that the water
from the deep strata will contain 2.3 mg/i fluoride and the shallow water
will contain no fluoride, a shallow/deep mix of 80 GPM/12O GPM will result in
a blend having a fluoride concentration of 1.4 mg/i.
COST
The estimated construction cost of the new well including engineering
and project contingency expenses has been estimated at $134,620.1 Annual
debt service expense on that amount calculated at 12% for 30 years is
$16,711. Other annual costs, such as power and chemical usage, are approxi-
mately proportional to demand and would not increase noticeably if production
were shifted from the existing well to the proposed new well. It may be con-
cluded, therefore, that the maximum additional annuel expense attributable to
the reduction in fluoride is equal to the debt service payment. Accordingly,
at a consumer population of 86. the annual cost increase per consumer served
would be 194.31 ($16.19/month) .
-5-
-------
IMPLEMENTATION
Design, securing permits and approvals, solicitation of proposals, contract
negotiation and award, and construction of the above-described facilities can
be accomplished within 24 months of completion of required referendums, rate
structure studies, funding procurement, etc.
OPERATOR REQUIREMENTS
Operator requirements for this system will not change as a consequence of
fluoride reduction in the water supply.
-6-
-------
REFERENCES
‘Palmer & Mallard and Associates, Inc., “Town of Stuckey, South Carolina,
Williamsburg County Preliminary Engineering Report Water Improvements”,
June, 1978.
2 Personal Communication, David Stuckey, Town of Stuckey, February 18, 1980.
-------
FLUORIDE REDUCTION
IN
PUBLIC WATER SUPPLY
OF
SULLIVAUS ISLAND
CHARLESTON COUNTY, SOUTH CAROLINA
‘JULY, 1980
Prepared For
SOUTH CAROLINA DEPARTMENT OF HEALTH
AND ENVIRONMENTAL CONTROL
Prepared By
A Joint Venture Of
J. E. SIRRINE COMPANY and AWARE, INC.
-------
TABLE OF CONTENTS
Page
INTRODUCTION 1
BACKGROUND
Consumers 2
WATER SUPPLY REQUIREMENTS
Current Demand 2
Projected Demand 3
Current and Projected Supply Requirements 3
EXISTING SUPPLY 3
FLUORIDE REDUCTION
Alternative No. 1: Blending
Method 5
Cost 6
Implementation 6
Operator Requirements 7
Alternative No. 2: Treatment
Method 7
Cost . . . . . . 7
Implementation 7
Operator Requirements 8
Summary 8
REFERENCES 9
APPENDIX
Fl uori de Treatment
-------
INTRODUCTION
Beginning on June 24, 1977, community water systems throughout the United States
were required to comply with the Environmental Protection Agency (EPA) National
Interim Primary Drinking tiater Standards. Said standards established maximum
contaminant levels for ten inorganic chemicals, one of which was fluoride. En-
forcement responsibility for the standards was requested by and subsequently
granted to the South Carolina Department of Health and Environmental Control
(SC DHEC). Investigations conducted by the State revealed that approximately
60 public water supplies exceeded the established fluoride standard. SC DHEC
personnel have worked with the affected communities in a concerted effort to
develop rational solutions to the problem. This report, which was funded by
EPA and prepared under the auspices of SC DHEC, is a direct outgrowth of that
effort.
In January, 1980, a study of each community water supply which exceeded the
legal limit for fluoride was initiated. The established objective of that in-
vestigative effort was to identify one or more viable fluoride reduction alter-
natives for each community. This report documents that portion of the study
which was directed specifically at providing a conceptual solution to the reduc-
tion of fluoride in the water supply of Sullivans Island. In addition to addres-
sing the conceptual solution from a technical standpoint, planning—level cost
estimates are also presented. It should be noted that all capital costs are
presented in 1980 dollars and that all operating expenses were calculated at 1979
water production and consumer levels.
—l —
-------
BACKGROUND
CONSUMERS
The water system serving the Town of Sullivans Island provided water to 790 con-
sumers as of March 30, 1978.1
A population projection for Sullivans Island was obtained from the Berkeley
Charleston Dorchester Council of Governments. Said projection was utilized to
develop consumer projections for the Town. The computations that were made are
suimiarized in the following table.
TOWN OF SULLIVANS ISLAND
CONSUMER POPULATION PROJECTIONS
Year
Population Projection
% Change
Consumers
1980
1985
1990
1995
2,234
2,802
3,396
4,000
-0-
25%
21%
18%
790
988
1,195
1,410
WATER SUPPLY REQUIREMENTS
Current Demand
Daily water demand in the service area was tabulated for two sixty-day periods
during calendar 1979. One period, January and February, experienced an average
daily demand of 177,166 gallons. The other, July and August, was approximately
2
42% higher with an average daily usage of 252,253. Based upon an annual average
of 215,000 GPD, the daily average use per connection was calculated to be 272
gallons.
—2-
-------
Projected Demand
Utilizing actual usage data for 1979 and the projected consumer population,
average daily water demands were calculated for 3 consecutive 5-year planning
periods. Maximum daily demand was also projected at 180% of average daily
demand. The results of said calculations are summarized in the following table.
TOWN OF SULLIVANS ISLAND
PROJECTED WATER DEMAND
Year
Average Day
(in gallons)
Maximum Day
(in gallons)
1980
1985
1990
1995
215,000
269,000
325,000
384,000
387,000
484,000
585,000
690,000
Current and Projected Supply Requirements
The below listed supply requirements were calculated utilizing a regulatory de-
sign criterion requiring that the well or wells be capable of meeting the maxi-
mum daily demand in a 16-hour operating period.
• 1980 - 403 GPM
• 1985 - 504 GPM
• 1990 - 609 GPM
• 1995 - 719 GPM
EXISTING SUPPLY
The Town has two separate points of supply. The first is located at the inter-
section of Station 17 and Middle Street. Shallow well water is collected by a
series of pump stations. Each pump station houses one (1) six—inch plunger pump
and is fed by 8 to 10 shallow (14 to 15 foot deep) well points. The approximate
—3..
-------
5
capacity of each station is 50 GPM. The series of pump stations convey water
via a 6” pressure main to a small (approximately 3 foot by 4 foot) concrete
mixing chamber which is constructed immediately adjacent to the existing deep
well. Water flows from the deep well under artesian pressure into the mixing
chamber. The blended water then flows a short distance by gravity to a 270,000
gallon concrete ground level storage tank. Booster pumps installed between the
ground level reservoir and the distribution system are utilized to maintain
system pressure. The water is chlorinated at the pump suction. During periods
of maximum demand, the flow from four of eight shallow well stations is blended
5
with the yield from the deep well.
The second water supply is located at the intersection of Station 24 and East
Middle Street. This supply consists exclusively of shallow well water which is
obtained from a series of pump stations located along East Middle Street. As
with the other supply, each pump station houses one (1) six-inch diaphram pump
which is fed by 8 to 10 shallow well points. The water is transmitted from the
pump stations to a 300,000 gallon ground level steel storage tank which serves as
a suction reservoir for the system’s booster pumps. Prior to being discharged
into the system, the water is chlorinated. As with the other supply, a maximum
of four stations pump to this tank during periods of maximum demand.
-4-
-------
FLUORIDE REDUCTION
Preliminary investigative efforts identified two viable fluoride reduction alter-
natives for Sullivans Island. Each alternative was subsequently evaluated to
determine the most practical and least expensive method of effecting a solution
to the fluoride problem. The ensuing paragraphs of this report document the
results of the evaluations and rank the alternatives in their order of desirabil-
i ty.
Financial information presented in this report is based upon 1979 consumer levels
and 1980 planning-level cost data. Consequently, the estimated consumer expense
reflects a present day situation. In other words, the assumption was made that
the alternative was constructed and became operational during the 1980 calendar
year. By utilizing current data, comparison of the various alternatives is
placed in a proper perspective with the community’s present fiscal position.
Recognizing that the cost data is presented in 1980 dollars, it is recommended
that initial planning of any alternative include a reevaluation of capital and
operating costs with respect to antidpated construction schedules.
ALTERUATIVE NO. 1: BLENDING
Method
Blending deep and shallow well water in the proper proportions on the western
end of the island will reduce the fluoride concentration in the Town’s water sup-
ply to acceptable levels. Based upon a deep well fluoride concentration of 4.7
mg/i and a shallow well concentration of 0.8 mg/i. blending ratios were calculated
and are presented in the following table. 3
—5—
-------
TOWN OF SULLIVANS ISLAND
DEEP/SHALLOW BLENDING RATIOS
Blend Ratio
(deep/shallow)
Flow Ratio
(deep/shallow)
Fluoride
Concentration
1.0/5.5
1.0/4.6
1.0/3.9
36 GPM/200 GPM
43 GPM/200 GPM
51 GPM/200 GPM
1.4 mg/i
1.5 mg/i
1.6 mg/i
The success of blending is dependent upon control of the flow from the deep well.
This can be accomplished by installing valves and meters in both the shallow and
deep feed lines immediately ahead of the mixing chamber. The flow from the deep
well can then be throttled to provide a flow that is properly proportioned to
the shallow well yield.
Being cognizant of the marginal capacity of the Town’s existing supply and the
obvious reduction in deep well yield that will occur as a result of throttling,
the construction of one additional shallow well station is included in this
alternative.
Cost
The estimated construction cost of Alternative No. 1 including engineering and
project contingency expenses has been estimated at $18,000. Annual debt service
expense on that amount calculated at 12% for 30 years is $2,234. Total system
operating costs would remain approximately the same.
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
24 months of completion of required referendums, rate structure studies, funding
procurement, etc.
—6—
-------
Operator Requirements
Operator requirements will not change as a consequence of this fluoride reduction
alternative.
ALTERNATIVE NO. 2: TREATMENT
Method
This alternative addresses the construction of one new deep well that will pro-
duce 500 GPM. The new facility will replace the existing deep well which is
6
reported to have a deteriorated casing which is leaking badly. Water produced
by the proposed well would be treated with activated alumina. The system would
be sized to treat 400 GPM, the remaining 100 GPM would bypass treatment and be
blended with the defluoridated water. A liquid waste stream from the unit will
be discharged to a wastewater equalization tank. The contents of the tank will
be drained to the sanitary sewer system at a low rate of flow.
See the Appendix entitled “Fluoride Treatment” for a description of the activated
alumina process.
Cost
The construction cost of Alternative No. 1 including engineering and project con-
tingency expenses has been estimated at $865,000. Annual costs are summarized
below.
• Debt Service on a 30—Year Loan at 12% $107,381
• Operations and Maintenance 50,619
Total Estimated Annual Cost Increase $158,000
Implementation
Design, securing permits and approvals, solicitation of proposals, contract nego-
tiation and award, and construction of this alternative can be accomplished within
—7—
-------
42 months of completion of required referendums, rate structure studies, funding
procurement, etc.
Operator Requirements
The State of South Carolina requires a licensed “A” operator for those systems
employing activated alumina fluoride removal technology. The present state li-
cense system requires a high school education, four years experience as an opera-
tor in a public water treatment plant, and the ability to pass a written
examination, in order to obtain an “A” operating license. Approximately 120 hours
of formal training should be adequate to upgrade operator skills to the level
required by the proposed treatment system. The actual cost to the comunity
for this training is anticipated to be approximately $3,000 plus travel and living
expenses.
SUMMARY
The alternatives which were evaluated during the course of this study are summa-
rized in the following table.
TOWN OF SULLIVANS ISLAND
ALTERNATIVE SUMMARY
Alternative
Capacity
(GPM)
Annual Cost Data
Capital
Operating
Per Consumer
No. 1: Blending
No. 2: Treatment
500
500
$ 2,234
$107,381
—
$50,619
$ 2.83
$200.00
Based upon the above listed information, Alternative No. 1 is the least expensive
method of effecting a solution to the fluoride problem in this community.
As of March, 1978, the average monthly water bill rendered for service from this
system was $9.84. Assuming that the increased annual cost for the selected alter-
native will be amortized uniformly, the average water bill will increase to $10.08.
-8-
-------
Construction of the primary alternative would result in the following water rate
increase.
1
• Existing monthly rate $9.84
• Estimated monthly increase . 24
Adjusted Monthly Water Rate $10.08/consumer
-9-
-------
REFERENCES
1 South Carolina Department of Health and Environmental Control, “Staff Study
for the Town of Sullivans Island, Charleston County,” March 30, 1978.
2 Personal comunication, Mrs. Bannister, Town of Sullivans Island, January 28,
1980.
3 South Carolina Department of Health and Environmental Control, water analyses
reports on laboratory samples numbered P06288-1419 and R06288-l654, July 3,
1978.
4 South Carolina Department of Health and Environmental Control, memorandum from:
Fred Soland, to: file, June 29, 1978.
5 Personal corrmunication, Mr. Truesdale, Town of Sullivans Island, April 23, 1980.
6 South Carolina Department of Health, Memorandum, From: Fred Soland, To: File,
Subject: Sullivans Island Water System, June 29, 1978.
-10-
------- |