NC0022900_Approval_20060919

September 19, 2006
Mr. Martin Lashua, Regional Manager
Carolina Water Service, Inc.
5701 Westpark Dr., Suite 101
Charlotte, North Carolina 28224
Dear Mr. Lashua:
Michael F. Easley, Governor
State of North Carolina
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
Subject: Backwash from WTP
Sugar Mountain WWTP
Permit NCO022900
Avery County
Division personnel have reviewed your letter regarding addition of the arsenic -containing backwash
from arsenic treatment system to the wastewater being treated at Sugar Mountain WWTP. Based on
the data you provided we have calculated the average arsenic concentration in the discharge to be
0.0014 µg/L, which is significantly lower than North Carolina water quality standard for arsenic.
Therefore, the Division concurs with your opinion and will not require the permit modification. The
Sugar Mountain WWTP is authorized to accept the backwash water from the arsenic treatment
system.
If you have any questions concerning this response, please contact me at telephone number (919)
733-5083, extension 594, or e-mail at sergei chemikov@ncmaiLnet.
Sergei Chernikov, Ph.D.
Environmental Engineer II
NPDES-West
cc: Central Files
Asheville Regional Office/Surface Water Protection Section
NPDES Unit
North Carolina Division of Water Quality - [phone]
1617 Mail Service Center FAX [phone]
Raleigh, North Carolina 27699-1617 On the Internet at http://h2o.enr.state.nc.us/

CAROLINA WATER SERVICE, INC.
AN AFFILIATE OF
Ul[ILL III ESoIFPXcu
Regional Office:
5701 Westpark Dr., Suite 101
P.O. Box 240908
Charlotte, NC 28224
Telephone: [phone]
FAX: [phone]
September 6, 2006
Ms. Susan Wilson, Supervisor
Western NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Re: Sugar MountainWWTP
NPDES NCO022900
Dear Ms. Wilson,
I hope this letter find you well.
l ,
I SEP $ 2006
I am writing at the suggestion of Roger Edwards with the Asheville Regional office. Carolina Water
Service, Inc. of NC (CWS) owns and operates the Sugar Mountain water and sewer utility system.
One of our potable water facilities needs Arsenic reduction treatment to comply with state and federal
maximum contaminant levels. Our plan submittal package is currently in the review process with
Public Water Supply Section (PWSS). Our treatment system proposal will require periodic
regeneration and "backwashing" for optimum performance. The waste backwash will go to our
sanitary sewer system. It is our understanding from a similar situation that PWSS is now requiring a
letter from DWQ stating that the receiving treatment plant is authorized to accept the backwash water
from the treatment system. Mr. Edwards has indicated that we may need an NPDES Permit
modification, which is the purpose of this letter.
Our wastewater facility is currently permitted for 0.5 MGD (a copy is enclosed for your use). The
backwash from the potable water facility would be approximately 965 gallons once every 9.5 days.
The Arsenic long term diluted contribution is projected at 0.0073 mg/l. I am enclosing a copy of the
treatment system design engineer's report. Please see the summary on pages 8 and 9 — they are of key
importance.
With such a miniscule flow contribution to a relatively large treatment plant, we strongly believe no
permit modification, or other action, is needed and hope that the Division will concur once you have
had the opportunity to evaluate the information presented.
We ask for your official position on this matter as quickly as possible as our PWSS plan approval may
be delayed until this is resolved or addressed.

Page 2
Ms. Susan Wilson
September 6, 2006
If you should need additional information or have any questions, please do not hesitate to call me at
704-525-7990, ext. 216, or by e-mail to [e-mail]. Thank you in advance for
your attention and assistance.
Si rely,
Martin Lashua
Regional Manager
Enclosures
CC: Rick Durham
Rex Woody
Roger Edwards — DWQ Asheville
Jerry Lowry — Lowry Engineering

Engineer's Report & Specifications
for
Modifications
to
Carolina Water Services of NC
Sugar Mt. Wells No. 21 & 22
Water Treatment System for
Arsenic Removal
PWSID # 01-06-107
Lowry Environmental Engineering, Inc
March 08, 2006

TABLE OF CONTENTS
Milli w.4ME ew:1991 21
I. Description & Identification of Existing Water System .........................1
Il. Name & Address of Owner...................................................................1
III. Provisions for Extension or Expansion
it
IV. Projection of Future Water Demand.....................................................1
V. Alternate Plans for Meeting the Water Supply Requirements .............2
VI. Financial Considerations of the Project................................................2
VII. Population Records & Trends, Water Demands, and
Yieldof Sources. ................................................................................. -2
VIII. Character of Water Supply...................................................................2
IX. Proposed Water Treatment Process....................................................3
A. Background Information on Arsenic Removal
& Treatment Processes........................................................................3
B. General Description of Facilities and Modifications .........................5
C. Criteria and Basis of Design............................................................5
D. Operation..........................................................................................9
SPECIFICATIONS
Ion Exchange Arsenic Removal System
Disinfection of New System ...................
StartUp .................................................
Piping.....................................................
APPENDIX A — Water Quality
APPENDIX B - Equipment Data Sheets
............................10
....................
:....... 11
............................11
............................11

Description & Identification of Existing Water System.
These plans and specifications modify a part of the Sugar Mt. Subdivision Water System
located in Avery County, NC. Sugar Mt. Subdivision has 1,514 connections that are served by a
total of 21 approved wells, and a new well under construction. Two (2) of the wells, No. 21 &
No. 22, are currently out of service due to elevated arsenic. Well No. 21 and No. 22 are
combined at Well No. 21 and treatment and a new treatment building are needed to meet the
arsenic MCL of 10 pg/L. These two wells have a combined capacity of 73 gpm and the total
capacity for all wells is 1,206.5 gpm. The system pressure at Well No. 21 is between 50 and 75
psi. There is a sewer system and WWTP that handle an average flow of 159,400 gpd. Three
(3) 200,000-gal atmospheric ground level storage tanks and one (1) 10,000-gal hydro
pneumatic tank provide a total of = 600,000 gal of storage in the system.
The average system water use for Well No. 21 and No. 22 is 52,560 gpd. These wells operate
an average of 12 hr/day. The pumping rates for Well No. 21 and Well No. 22 are 27 gpm and
46 gpm, respectively.
This report is supplemental to the entire project being designed and submitted by Davis -
Martin -Powell & Assoc., 6415 Old Plank Road, High Point, NC 27265-3274 (Michael Goliber,
PE).
fl. Name & Address of Owner
The water system is owned and operated by Carolina Water Services of NC (CWS-NC). The
business address is PO Box 240908, 5701 Westpark Dr., Suite 101, Charlotte, NC 28224.
III. Provisions for Future Extension or Expansion of the Water System
Not Applicable
IV. Projection of Future Water Demand or Requirements for Service
Not Applicable
1

V. Alternate Plans for Meeting the Water Supply Requirements
The Owner has considered 1) acquiring land to replace the well supply with a new
well(s) of equal capacity, and 2) providing a treatment system to remove the contaminant. Land
costs prohibit the first option, therefore, treatment is the only feasible alternative.
Ion exchange (IX) was selected as the most cost effective process for arsenic removal.
Due to the simplicity of the process, the effectiveness of arsenic removal, the low level of
sulfate, and the availability of a sewer, IX is much more cost effective than all other arsenic
treatment alternatives. General background information about arsenic treatment and the
process design detail are given in Section IX
VI. Financial Considerations of the Project
a. Costs for Modifications (Treatment Only)
The IX treatment system to remove arsenic will cost approximately $51,000, including
engineering, pre -piping, and startup. Anticipated O&M costs are $750/year for salt (NaCI) and
$2,500/year for process labor. Power costs are estimated at less than $20/yr for the IX controls.
b. Methods of Financing Modifications & Operations
Carolina Water Services of NC will fund the proposed project.
VII. Population Records & Trends, Water Demands, and Yield of Sources
The treatment proposal modifies the existing water system at the Sugar Mt. Subdivision. It does
not increase the approved capacity of the water system. The proposed modifications are
designed to meet specific water quality requirements to allow the system to operate within the
standards of the Safe Drinking Water Act (SDWA).
Vill. Character of Source Water Supply
The water quality of Wells No. 21 and No. 22 is good, with the exception of high arsenic. The
2

arsenic level is 49-50 pg/L and an arsenic speciation conducted in the field on 01/11/06 showed
6 pg/L As III and 44 pg/L As V. The pH is 6.7 and the sulfate is 5.0 mg/L. Phosphate (PO4) and
silica are 0.07 mg/L and 14.1 mg/L, respectively. Hardness is moderately high in Well No. 2, at
approximately 150-200 mg/L (varies). Iron and manganese are very low as shown below:
4/3101 - both wells combined < 0.05 mg/1
4/7/04 - both wells combined - 0.573 mg/I (Note well was not operational and not properly flushed before sampling)
6/2104 well #21 < 0.06 mg/1
6/2/04 well #22 < 0.06 mg/I
6/21/04 well #21 < 0.06 mg/I
6/21/04 well #22 < 0.06 mg/l
The radioactivity, inorganics, organics, and bacteriological results are further detailed in
Appendix A.
IX. Proposed Water Treatment Process
A. Background Information on Arsenic Removal and Treatment Processes
Arsenic V is readily removed by a number of processes, including conventional iron
oxidation and filtration, anion exchange, granular ferric hydroxide media adsorption, activated
alumina (AA), Fe -modified AA, coagulation -micro -filtration (CMF), and reverse osmosis (RO).
As III is poorly removed by all of these processes, so oxidation to As V is a required pre-
treatment step if As III is present.
The inlet water quality is the primary factor in selecting the most cost-effective treatment
process alternative, according the following conditions:
1) In cases where an iron removal process already is used, it can be optimized for arsenic removal, and
will likely be the most cost-effective alternative.
2) If iron is low in the well water and a sewer is available for a wastewater brine discharge, anion
exchange will be the most cost-effective altemative. Anion exchange is insensitive to pH, silica, and
phosphorous, and it is very effective at producing low arsenic in the treated water. Its effectiveness is
dependent on the inlet sulfate level, with lower sulfate giving longer service runs. Sulfate is preferred
over arsenic by strong base anion resin. Service runs of over 3,000 bed volumes (BV) can be achieved
at sulfate levels <10 mg/L. The bed capacity might be reduced to approximately 300 BV at a sulfate level
200-250 mg/L. Although the service capacity of anion exchange is much less than some of the once -use
granular media, the resin lasts for decades and regeneration with salt is very low cost compared to
replacing once -use iron media. In a favorable application to each process, anion exchange might have

as tow as 1/IOP to 1/15"' the cost of operating a once -use granular Fe -based adsorption system, even if
the adsorption system achieves a 50,000-75,000 BV service run. Anion exchange has been used for 15
years in arsenic applications.
3) Where a brine (IX) or acid/base (AA) regeneration discharge is not possible, IX and AA would typically
not be feasible, because they could not be regenerated on -site. In certain cases where the pH is low
(optimum 6.0-6.5), AA or Fe -AA may be feasible as "once -use" madia. These two forms of AA are very
low-cost compared to the more -effective granular Fe -based media. IX is too expensive to use on a once -
use basis because its capacity would be less than 4,000 BV even if sulfate were near zero. A modified
iron -impregnated anion resin (Arsenex) is now available with a much higher capacity that is similar to Fe -
based media. Arsenex resin can be regenerated off -site at a special facility in TN, or it can be used once
and disposed of in a landfill. Currently, Arsenex is more costly than Fe -based media, but it has a superior
structural integrity, lower head loss, and no fines to remove by backwash. As a result, it is being used
extensively in POE applications on a once -use basis.
4) Fe -based granular adsorption media have become popular in recent years, based on the promise that
a sewer discharge of arsenic will be avoided and that the operation of these system will be simple. Mixed
results have been observed with these media. While they can be used with good success in favorable
conditions, there have been problems with the general low structural integrity (friability) compared to other
types of granular media used in non -arsenic filter applications (GAC, sand, coal, garnet, greensand,
manganese dioxide, etc.). In some applications, the low structural integrity has led to problems of high
head loss and frequent backwashing requirements, due to the generation of fines that must be removed
periodically. In the worst cases, unanticipated daily backwash has been necessary just to keep the filter
beds running. When this happens during a treatment run, the fines that go to the sewer contain high
levels of adsorbed arsenic and the non -discharge advantage of the process disappears. The exceptions
are Arsenex and Fe -AA. They do not have a problem with fines.
Granular Fe -based media perform optimally at pH 6.0-6.5 and lose capacity as the pH rises. At pH 8.0
the capacity of commonly used media brands can be reduced to up to 1/10th that of an optimum
operation. Optimally, these systems have achieved 100,000+ BV service runs. To achieve that
performance, the pH must be optimal, or lowered to optimal by strong acid or carbon dioxide addition, and
phosphorous and silica must also be low. Phosphorous competes with arsenic above 0.05 mg/L (P), and
can cause a significant reduction in performance above 0.10 mg/L. High silica has been known to forma
glass -like precipitate that can blind the particle surface and cause very poor performance. With non -
optimum water quality, the Fe -based media may only achieve service runs as low as 5,000-10,000 BV. In
general, these media are expensive and need to achieve >50,000 BV to even begin to be cost-effective.
Typically, these media should not be considered if iron removal processes, IX, or Fe -AA are feasible
alternatives. While the suppliers of Fe -based adsorption systems refer to their systems as being ones
requiring no wastewater disposal or sewer discharge, this is not the case in all applications to date.
Unanticipated backwashing produces iron fines with highly elevated adsorbed arsenic, and this typically
goes to a sewer or disposal field.
Of importance is a newer Fe -based media (Kemiron) that is harder and has a significantly larger particle
size. This is reported to reduce the fines problem and a much lower head loss is typical. In addition,
several pilot tests have shown that the media has excellent capacity that is significantly higher than other
Fe -based media included in the comparisons (GFH Wor Ba-33). It can also be used in an up flow mode
and backwashing is avoided after the initial backwash at startup. Finally, tests show that it performs
much better than other Fe -based media at higher pH (up to 8.5). This is important because it may
eliminate the need to lower the pH at sites that have higher pH. Lowering pH with acid requires an
addition of caustic to raise the pH after treatment, or to strip the carbon dioxide that was used to lower the
pH prior to treatment.

B. General Description of Facilities and Modifications
This proposal intends to remove arsenic. The treatment equipment consists of two (2)
36"x60" SSW (straight side wall) epoxy -coated steel ASME-coded (150 psig) pressure vessels
and one (1) 39"x48" poly brine tank. The proposed treatment process does not break pressure
and the expected head loss is less than 10 psig (approx. 5-7 psi). The treatment system is
detailed in Sheets LEE-1 and LEE-2, and will be housed in an expanded building at Well No. 21.
This construction is detailed in the Plans and Specifications by Davis -Martin -Powell & Assoc.,
6415 Old Plank Road, High Point, NC 27265-3274 (Michael Goliber, PE). A pressure reduction
will be designed prior to treatment and an in -line sediment filter (cartridge -type) will be used to
eliminate any potential for sand to be trapped in the IX vessels.
Salt (NaCI) for regenerating the IX beds will be stored in the brine tank and in the
building. Additional space will be provided for the possibility of additional wells to be treated in
the future. A chlorine addition point will provided before and after IX treatment. The pre-
treatment chlorine addition may be used to ensure the oxidation of any As III to As V, because
any arsenic treatment process removes As V much better than As III. The chlorine before IX
will be kept below 0.5 mg/L, as chlorine is removed by anion resin and high chlorine could
cause long-term degradation. There is ample contact time (=3 min) for As III oxidation.
Oxidation of As III with chlorine is rapid, and typically requires less than 15 seconds.
The IX waste brine and rinse waters will be discharged to the Sugar Mt. WWTP (NPDES
NC0022900) via a line to the existing sewer. Regeneration will be relatively infrequent, at
approximately every two weeks, and the sewer flow rate is relatively large in comparison to the
water treated at Well No. 21 and No. 22.
C. Criteria and Basis of Design
Ion exchange is a cost-effective arsenic removal process if the well water quality is
favorable and a sewer is available for regenerant wastewater. In general, the IX process is very
effective, reliable, and able to perform well over a wide range of pH. Fortunately, all aspects of
this water quality favor the use of IX and a relatively large sewer is available for regeneration.
The important inlet water design parameters are shown in Table LEE -I.

Table LEE -I. Summary of Important Well Water Quality Parameters
Parameter
No. 21 & 22
Notes
Total Arsenic, pg/L
49 & 50
Two analyses
Arsenic V, pg/L
44
Arsenic III, pg/L
6
Sulfate, mg/L
5
N}�
pH
6.6-6.9
Alkalinity, mg/L
Iron, mg/L
<0.06
Manganese, mg/L
<0.06
Arsenic is removed by the exchange of more -preferred anions with chloride ions. Sulfate
has the most impact on the operation of IX for arsenic removal because it is preferred over
arsenic. Sulfate is removed for the entire service cycle, and it determines the bed capacity of the
resin for arsenic, since sulfate will displace arsenic if the bed is operated to arsenic
breakthrough. By design, the IX system is regenerated before arsenic breakthrough, so it is the
amount of sulfate that controls the number of BV that can be treated before the resin needs to
be regenerated. This is illustrated in Figure LEE-1.
The combined supply from Well No. 21 and No. 22 has a sulfate level of only 5 mg/L. As
seen in Figure LEE-1, this means that the capacity for arsenic removal by IX will be relatively
high. The estimate for this particular water quality is =3,000 BV, which will give a service time of
approximately 19 days.
Carbon dioxide produced by the removal of bicarbonate (bicarbonate releases a
hydrogen ion when carbonate is removed on the resin) causes the pH to be lowered during the
first 300-500 BV following regeneration. After the capacity for alkalinity is satisfied, the pH and
alkalinity return to the inlet values. Since this period of lower pH and increased corrosivity will
occur for only 10-15% of the service run, its effect will be minimal. Further reduction of this
effect is brought about by: 1) operating the two IX vessels out -of -phase, so that one is operating
beyond the point of alkalinity removal, 2) dilution with previously treated water in the system, 3)
downstream alkalinity addition with caustic, and 4) addition of phosphate. As a result, the

2000
1800
1600
x 1400
0
0
1200
S�c i o00
a
a 800
O
H
m 600
400
200
0 50 100 150 200 250 300 350
SULFATE, mg/L
Figure L€€-1. Capacity of an IX Resin for Arsenic as a Function of Sulfate
increase in corrosivity is effectively handled by normal operation of the treatment system. Two
(2) parallel IX vessels are provided, to be operated in parallel to bring arsenic to below 5 pg/L at
all times. The important water quality parameters with respect to the treatment system are
summarized in Table I.
The capital cost for an IX plant is relatively low due to the rapid kinetics of the process
and the resulting short EBCT that is required. The EBCT of 1.5 min is often cited as an
acceptable design value, and practical design considerations normally provide more than 1.5
min. This particular design provides an EBCT of 4.51 min. It is important to operate multiple
parallel IX vessels in a staggered, or out -of -phase, operation to minimize the treated water
quality changes. Specifically, this operation minimizes peaking, should it occur, allows a vessel
to be left in service longer, and minimizes the fluctuation in alkalinity and pH, as described
above. A summary of treatment process design parameters is given in Table LEE-ll. The
treatment system details are shown in Sheet LEE=1 and LE&2 of the accompanying Plans.
7

Table LEE -II. Ion Exchange Design Summary
Parameter
Value
Notes
Treated Arsenic, L
<5
No. of Treatment Units
2
Operated in parallel with staggered service
Vessels (2), steel/epoxysteel/epoxy
36x60 SSW
Anion Resin: 22 cu ft/vessel x 2 = 44 cu ft
EBCT, min
4.51
OK to treat entire flow through one vessel while
the second is regenerating. EBCT = 2.25 min
Regeneration Water
Treated
Brine Tank, poly
250- al
39"x48" 2200 lb Salt Capacity w/brine Valve
Extemal piping
2" Galy.
Per Utility Specifications
Extemal Manual Valves
Ball
Backwash rate, m/sf
2.12
-45%expansion
Backwash flaw, Spm
15
Design cl_e length, BV
-3,000
Field adjustable based on performance and
inlet and treated water quality
Design cycle time, days
18.8
Avg. BV per day
160
Regeneration volume; BV/cu ft per cycle
5.9
965/re n/vessel x 2 = 1,930 I
Disposal of Re-enerant Water
sewer
Waste to be discharged to Sugar Mt. W WTP
NPDES NC0022900
Avg. waste,gal/day
103
Arsenic in Waste, m /L
22.6
Salt used, lb/cycle
440
10lb/cf resin (conservative)
Na in Waste. m /L
10,757
Ct in Waste, /L
24,044
Conservative: assumes no chloride exchanged
Averse Sewer Flow, gpd
159,400
Average of previous 12 months
Long-term Diluted As in sewage flow, m /L
0.0073
Lo term Diluted Na in sewage flow, /L
3.5
Long-term Diluted Cl in sewage flow, m /L
5.3
M-
C--
Field sampling and operation adjustments will be made after the system is started, to
determine the optimum operating parameters and service capacity (BV). The IX bed is
regenerated with sodium chloride (salt) and the service period will be based on arsenic removal.
There is no good surrogate for As, but there have been two (2) field kits recently evaluated by
Penn. State University that accurately detect arsenic at the MCL level. The operator will use a
field kit to check arsenic in normal operation.
It is expected that the IX service period will be -3,000 bed volumes (BV; one BV = the
gross volume of the resin, e.g., 1 cu ft resin will treat 3,000 cu ft of water). This translates to a
service period of approximately 18.8 days, given the average demand and pumping period of
3

the well. During this service period, the system will treat 494,000 gal, and will produce 1,930
gal of wastewater every -18.8 days, or approximately 103 gal/day. The vessels will be
regenerated with treated water and regeneration will take approximately 114 minutes per bed.
On average, one vessel will regenerate every 9.5 days.
Disposal will be by sewer to the Sugar Mt. WWTP (NPDES 0022900). The average
long-term diluted contributions of arsenic, sodium, and chloride in the total wastewater will be
0.0073 mg/L, 3.5 mg/L, and 5.3 mg/L, respectively.
D. Operation
The IX treatment system will be operated to treat the entire well flow, using two (2)
pressure vessels in parallel as described above. Each vessel will be operated using a totalizing
flow meter, an automatic demand -based microprocessor control, and a "nest" of multiple
diaphragm valves. As a backup system, there will be a timer override (adjustable) to ensure
that regeneration takes place after a preset service period in the event the flow -based
regeneration does not occur within the expected time period. The programmable controller and
diaphragm valves for operation of the system are detailed in Sheet LEE-1 and LEE-2. The
diaphragm valves are operated by air or water pressure.
The resin bed will be regenerated using the following steps: 1) backwash, 2) brine, 3)
slow rinse, 4) fast rinse, and 5) brine tank refill. The total amount of water used for regeneration
will be equal to 5.9 BV (965 gal/reactor) and the various regeneration steps are programmed
with times for specific flow rates as follows:
1. Backwash = 15 gpm for 15 min 2. Brine = 6.94 gpm for 29 min
3. Slow Rinse = 4.0 gpm for 60 min 4. Fast Rinse = 30 gpm for 10 min
5. Brine Refill = 85 gal Total Regan. Time = 114 min (wo/refill)
The estimated salt usage rate at 10 Ib/cu ft resin is only -24 lb/day (1/2 bag) and this
figure is conservative. It may be that a salt rate of =60% of this figure will be normal operation,
as arsenic can be effectively regenerated off the resin at a salt dose of 6 Ib/cu ft. The brine tank
working capacity is 1100 Ibs (1/2 rated salt capacity). This translates to a salt capacity of 6
weeks in the brine tank. Salt deliveries every quarter would be practical, With a requirement for
=2,000 lb (50-lb bags) of salt being delivered and stored in the building.

Specifications
ION EXCHANGE ARSENIC REMOVAL SYSTEM
The complete IX system shall be supplied as a design -build project for CWS-NC, Inc.
Piping manifolds for the units will be done at the factory and the unit will be skid -mounted and
pre -piped. CWS-NC will do all field connections to the building piping, including the inlet (1),
cutlet (2), regen supply (1), and the drain to sewer (1). The specifications for the equipment are
given in Table LEE -III.
Table LEE -III. Sugar Mt. Subdivision Equipment Summary
Item Description/System Quantity
36" diameter x 60" SSH, ASME-coded, 150 psig. One (1) 11"x15" man -way at
top, one (1) 4"x6" hand -way at bottom side. Full coupling SS 2" NPT inlet and
outlet ports in side shell/bottom. One (1) top center SS 2.0" NPT relief fitting plus
SS 2.0" media removal port and SS brine distributor fitting, as detailed in Sheet
Steel Pressure Vessel
LEE-1 and LEE-2.
2
Epoxy -lined interior- Tnemec Series 20 multi -coat at 10-12 mils (ANSI/NSF 61).
Tank Coatings
Exterior painted with 2-part Tnemec Series 1601161 True Safety Blue.
2
Bottom: 2" bottom-pcirt entry Sch 80 PVC hub and lateral W0.010" slots. Top, 2"
Bottom; Top; and Brine
side port entry vertical PVC pipe distributor:
Distributors
Brine: side port fitting and distributor, as detailed in Sheet LEE-1 and LEE-2.
2
Osmonics/Aquamafic Model 962 programmable electronic demand -based
Regeneration Controls
monitoring & control unit.
2
Osmonics/Aquamatic Series 420 and 420E diaphragm valve nest. Diameters,
Diaphragm Valves
numbers, and types as detailed in Sheet LEE-1 and LEE-2.
2
Flow Meter
Seametrics 2" turbine meter
2
Brine Tank
Structural Model 3948 250-gal and 2200 lb capacity
1
ASTM-approved 2" galvanized steel pipe and fittings per CWS-NC "Construction
Specification Details"; w/Union Apollo ball valves for isolation, 2 oil -filled pressure
gauges/vessel, sample valves, and pressure relief/vacuum relief/air check valve
essel Piping
assembly. Piping done at factory.
1
Gravel Underbed
Cover for laterals -1/4" x 1/8"
2
Anion Resin
2 x 22 = 44 cu ft A300E Anion Resin (Purolite or equal)
44
10

DISINFECTION OF NEW SYSTEM
All new equipment and piping will be chlorinated following the rules detailed in Section
.1001, .1003, and .1004.c, of the North Carolina Administrative Code, Title 15A, Subchapter
18C. The resin can be regenerated when put into service and the regenerant brine can have >1
ppm free chlorine. This is not normally done but will be done if necessary. A long contact time
with high chlorine (>1 ppm) should be avoided with IX resin, and the resin is never
"superchlorinated".
START UP
The system shall be put into service and monitored for a 3-week period to ensure proper
installation and operation through a complete cycle. One of the two units will be regenerated at
1/2 capacity (=9 days), to get the two IX vessels into a staggered (out -of -phase) operation. One
set of samples (well and treated) shall be taken for arsenic analysis after 24 hrs of operation.
PIPING
All piping will be done in accordance with CWS-NC "Construction Specification Details",
using ASTM-approved 2" galvanized steel pipe and fittings.
11