EPA/600/R-06/083
September 2006
Arsenic Removal from Drinking Water by Adsorptive Media
U.S. EPA Demonstration Project at Valley Vista, AZ
Six-Month Evaluation Report
by
Julia M. Valigore
Lili Wang
Abraham S.C. Chen
Battelle
Columbus, OH 43201-2693
Contract No. 68-C-00-185
Task Order No. 0019
for
Thomas J. Sorg
Task Order Manager
Water Supply and Water Resources Division
National Risk Management Research Laboratory
Cincinnati, Ohio 45268
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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DISCLAIMER
The work reported in this document is funded by the United States Environmental Protection Agency
(EPA) under Task Order 0019 of Contract 68-C-00-185 to Battelle. It has been subjected to the Agency's
peer and administrative reviews and has been approved for publication as an EPA document. Any
opinions expressed in this paper are those of the author(s) and do not, necessarily, reflect the official
positions and policies of the EPA. Any mention of products or trade names does not constitute
recommendation for use by the EPA.
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FOREWORD
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation's
land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to
formulate and implement actions leading to a compatible balance between human activities and the ability
of natural systems to support and nurture life. To meet this mandate, EPA's research program is
providing data and technical support for solving environmental problems today and building a science
knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect
our health, and prevent or reduce environmental risks in the future.
The National Risk Management Research Laboratory (NRMRL) is the Agency's center for investigation
of technological and management approaches for preventing and reducing risks from pollution that
threaten human health and the environment. The focus of the Laboratory's research program is on
methods and their cost-effectiveness for prevention and control of pollution to air, land, water, and
subsurface resources; protection of water quality in public water systems; remediation of contaminated
sites, sediments and ground water; prevention and control of indoor air pollution; and restoration of
ecosystems. NRMRL collaborates with both public and private sector partners to foster technologies that
reduce the cost of compliance and to anticipate emerging problems. NRMRL's research provides
solutions to environmental problems by: developing and promoting technologies that protect and improve
the environment; advancing scientific and engineering information to support regulatory and policy
decisions; and providing the technical support and information transfer to ensure implementation of
environmental regulations and strategies at the national, state, and community levels.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is
published and made available by EPA's Office of Research and Development to assist the user
community and to link researchers with their clients.
Sally Gutierrez, Director
National Risk Management Research Laboratory
in
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ABSTRACT
This report documents the activities performed and the results obtained from the first six months of the
EPA arsenic removal technology demonstration project at the Arizona Water Company (AWC) facility in
Sedona, AZ, commonly referred to as Valley Vista. The main objective of the project is to evaluate the
effectiveness of Kinetico's FA-236-AS treatment system using AAFS50 media in order to remove arsenic
to meet the new arsenic maximum contaminant level (MCL) of 10 |o,g/L. Additionally, this project
evaluates the reliability of the treatment system for use at small water facilities, the required system
operation and maintenance (O&M) and operator skill levels, and the cost-effectiveness of the technology.
The project also characterizes water in the distribution system and residuals generated by the treatment
process. The types of data collected include system operation, water quality (both across the treatment
train and in the distribution system), process residuals, and capital and O&M costs.
The FA-236-AS system consists of two 36-in-diameter, 72-in-tall fiberglass tanks in series (lead/lag),
each containing 22 ft3 of AAFS50 media. The media is an iron-modified activated alumina (AA) medium
manufactured by Alcan. The system was designed to treat 37 gal/min (gpm) of flow with an empty bed
contact time (EBCT) of 4.5 min/tank and 9.0 min for both tanks. For the first of two media runs
performed during the first six months of system operation, due in part to the use of an incorrect media
density, the vendor inadvertently loaded 16.7 ft3 (i.e., 1,100 Ib) of AAFS50 media into each tank,
resulting in a shorter EBCT of 3.4 min/tank.
After extensive engineering plan review and approval by the state and county drinking water officials, the
treatment system was installed in May 2004 and became operational on June 24, 2004. During the first
six months, the treatment system operated for 24 hr/day with less than 1% downtime for repairs and
media replacement. The source water contained 34.8 to 47.6 |o,g/L of total arsenic, with As(V) being the
predominating species, averaging 41.8 |o,g/L. Prechlorination, although not required for oxidation, was
performed after a month into the study to inhibit biological growth in the adsorption tanks and to provide
residual chlorine in the distribution system.
The raw water pH values, ranging from 7.5 to 8.4 and averaging 7.8, were not adjusted during the first
media run. After treating approximately 8,200 and 16,900 bed volumes (BV) of water, the effluent from
the lead and lag tanks exceeded the 10-|a,g/L arsenic breakthrough limit on July 14 and August 4, 2004,
respectively. (Note that BV was calculated based on 16.7 ft3 [125 gal] of media in the lead tank.) Based
on the breakthrough curves, the arsenic adsorptive capacity of the media without pH adjustment was
estimated to be 0.31 mg/g of media at 10-|a,g/L arsenic breakthrough and 0.6 mg/g of media near
exhaustion. An effort to extend the media life by lowering the pH value to 6.8 using H2SO4, beginning on
September 17, 2004, reduced the arsenic concentrations after both tanks (i.e., 33 to 24 |o,g/L and 26 to 16
|o,g/L in the lead and lag tanks, respectively), but not to the desired level of 10 |og/L. Therefore, the spent
media in both tanks was replaced on October 25, 2004, and disposed of as non-hazardous waste after
passing the Toxicity Characteristic Leaching Procedure (TCLP) tests.
For the second media run, the raw water pH was adjusted to 6.7 to 6.9. As of December 15, 2004, the
new AAFS50 media had treated approximately 2,635,000 gal, or 16,000 BV of water, leaving 4.3 |o,g/L
and 0.1 |og/L of total arsenic in the effluent from the lead and lag tanks, respectively. Therefore, pH
adjustment significantly increased the media's arsenic adsorptive capacity. Concentrations of iron,
manganese, silica, orthophosphate, and other ions in raw water were not high enough to impact arsenic
removal by the media.
Comparison of the distribution system sampling results before and after the commencement of the system
operation showed a decrease in arsenic concentration, most prominently at one sampling location close to
IV
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the treatment plant (from 34.9 to 51.8 |o,g/Lto 0.3 to 23.9 ng/L). Arsenic concentrations at the other two
locations were much higher than those of the treatment effluent presumably due to the blending of
untreated water from other wells supplying the distribution system. The lead and copper concentrations at
the three sampling locations did not show a clear pattern of the arsenic treatment system's impact.
Backwash of the filter media was performed monthly based on a set throughput of 1,400,000 gal using
treated water at 27 to 36 gpm, or 3.8 to 5.1 gpm/ft2. No significant pressure buildup was observed during
service runs. Each backwash lasted for 40 min (20 min/tank), producing between 1,060 and 1,400 gal of
water. Average soluble arsenic concentrations in the backwash water from the lead and lag treatment
tanks were 31.9 and 15.2 |o,g/L, respectively. A backwash recycle loop enabled the system to reclaim
nearly 100% of the wastewater produced by blending it with the feed water at a maximum rate of
3.6 gpm.
The capital investment cost of the system was $228,309 consisting of $122,544 for equipment, $50,659
for site engineering, and $55,106 for installation. Using the system's rated capacity of 37 gpm (or
53,280 gal/day [gpd]), the capital cost was $6,171/gpm (or $4.29/gpd). This calculation does not include
the cost of the sun shed enclosure which houses the treatment system.
The O&M cost for the treatment system included only incremental cost associated with the FA-236-AS
system, such as media replacement and disposal, chemical supply, electricity consumption, and labor.
Representing the majority of the O&M cost, the media replacement and disposal cost depended on the
number of tanks to be changed out when the arsenic breakthrough following the lag tank reached 10 |o,g/L.
Without pH adjustment, it might be more convenient and cost-effective to replace the media in both tanks
together to reduce the changeout frequency and minimize the associated scheduling and coordinating
effort. The cost for replacing media in both tanks was estimated at $6,623 (for 33.4 ft3, the total amount
of media used during the first media run) or $3.15/1,000 gal of water treated. With pH adjustment, the
media run length was significantly increased so that only the media in the lead tank might be replaced at
an estimated cost of $4,363 for 22 ft3 of media. Adjustment of pH lowered the media replacement cost,
but added a chemical cost of $0.66/1,000 gal of water treated. The total O&M cost and media
replacement cost per 1,000 gal of water treated were plotted as a function of the media run length.
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CONTENTS
DISCLAIMER ii
FOREWORD iii
ABSTRACT iv
FIGURES vii
TABLES vii
ABBREVIATIONS AND ACRONYMS viii
ACKNOWLEDGMENTS x
Section 1.0: INTRODUCTION 1
1.1 Background 1
1.2 Treatment Technologies for Arsenic Removal 1
1.3 Project Objectives 2
Section 2.0: CONCLUSIONS 3
Section 3.0: MATERIALS AND METHODS 5
3.1 General Project Approach 5
3.2 System O&M and Cost Data Collection 6
3.3 Sample Collection Procedures and Schedules 7
3.3.1 Source Water Sample Collection 7
3.3.2 Treatment Plant Water Sample Collection 7
3.3.3 Backwash Water Sample Collection 7
3.3.4 Distribution System Water Sample Collection 7
3.3.5 Residual Solid Sample Collection 10
3.4 Sampling Logistics 10
3.4.1 Preparation of Arsenic Speciation Kits 10
3.4.2 Preparation of Sampling Coolers 10
3.4.3 Sample Shipping and Handling 10
3.5 Analytical Procedures 11
Section 4.0: RESULTS AND DISCUSSION 12
4.1 Facility Description 12
4.1.1 Source Water Quality 12
4.1.2 Distribution System 13
4.2 Treatment Process Description 15
4.3 System Installation 20
4.3.1 Permitting 20
4.3.2 System Installation, Shakedown, and Startup 20
4.3.3 Shed Construction 20
4.4 System Operation 20
4.4.1 Operational Parameters 20
4.4.2 pH Adjustment 22
4.4.3 Backwash 23
4.4.4 Media Changeout 23
4.4.5 Residual Management 23
4.4.6 Reliability and Simplicity of Operation 24
4.5 System Performance 25
4.5.1 Treatment Plant Sampling 25
4.5.2 Backwash Water Sampling 31
VI
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4.5.3 Distribution System Water Sampling 32
4.5.4 Spent Media Sampling 34
4.6 System Cost 35
4.6.1 Capital Cost 35
4.6.2 O&MCost 36
Section 5.0 REFERENCES 40
FIGURES
Figure 3-1. Process Flow Diagram and Sampling Locations 9
Figure 4-1. Predemonstration Site Conditions 12
Figure 4-2. Existing Chlorine Injection System 13
Figure 4-3. Schematic of Kinetico's FA-236-AS Treatment System 17
Figure 4-4. Kinetico's FA-236-AS Treatment System on Concrete Pad 18
Figure 4-5. Treatment Process Components 19
Figure 4-6. Backwash Process Components 19
Figure 4-7. Sun Shed Structure (Top) and Completed Enclosure (Bottom) 21
Figure 4-8. Total Arsenic Concentrations and Treatment pH over Time 28
Figure 4-9. Alkalinity, Sulfate, and pH Values over Time 30
Figure 4-10. Silica Concentrations over Time 31
Figure 4-11. Media Replacement and O&M Cost without pH Adjustment 38
Figure 4-12. Media Replacement and O&M Cost with pH Adjustment 38
TABLES
Table 1-1. Summary of Round 1 Arsenic Removal Demonstration Technologies and Source Water
Quality Parameters 2
Table 3-1. Predemonstration Study Activities and Completion Dates 5
Table 3-2. Evaluation Objectives and Supporting Data Collection Activities 6
Table 3-3. Sampling Schedule and Analyses 8
Table 4-1. POE Well No. 2 Water Quality Data 14
Table 4-2. Distribution System Water Quality Data(a) 15
Table 4-3. Physical and Chemical Properties of Alcan's Actiguard AAFS50 Media 15
Table 4-4. Design Features for Kinetico's FA-236-AS Treatment System 18
Table 4-5. Operation of FA-236-AS Treatment System 22
Table 4-6. Summary of Backwash Events 23
Table 4-7. Summary of Arsenic, Iron, Manganese, and Aluminum Results (06/24/04-12/22/04) 26
Table 4-8. Summary of Other Water Quality Parameter Results (06/24/04-12/22/04) 27
Table 4-9. Theoretical Calculation of Acid Consumption for pH Adjustment 31
Table 4-10. Backwash Water Sampling Results 32
Table 4-11. Distribution System Sampling Results 33
Table 4-12. Spent Media Total Metal Analysis 34
Table 4-13. Summary of Arsenic Removed by AAFS50 Media 34
Table 4-14. TCLP Results of Spent Media 35
Table 4-15. Capital Investment for Kinetico's Treatment System 35
Table 4-16. O&M Cost during First Media Run (06/24/04 - 08/04/04) 37
Table 4-17. O&M Cost during Second Media Run (10/25/04 - 12/22/04) 37
vn
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ABBREVIATIONS AND ACRONYMS
Ap differential pressure
AA activated alumina
AAL American Analytical Laboratories
ADEQ Arizona Department of Environmental Quality
Al aluminum
AOC Approval of Construction
APU arsenic package unit
As arsenic
ATC Approval to Construct
AWC Arizona Water Company
bgs below ground surface
BV bed volume(s)
Ca calcium
CCR Consumer Confidence Report
Cl chlorine
CRF capital recovery factor
Cu copper
DO dissolved oxygen
EBCT empty bed contact time
EPA U.S. Environmental Protection Agency
F fluoride
Fe iron
FRP fiberglass reinforced plastic
gpm gallons per minute
H2SO4 sulfuric acid
HOPE high-density polyethylene
ID identification
IX ion exchange
kwh kilowatt-hour(s)
LCR (EPA) Lead and Copper Rule
LOU Letter of Understanding
MCL maximum contaminant level
MDL method detection limit
MDWCA Mutual Domestic Water Consumer's Association
Mg magnesium
jam micrometer
Mn manganese
Vlll
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Mo
mph
mV
molybdenum
miles per hour
millivolts
Na sodium
NA not applicable
NaOCl sodium hypochlorite
ND not detected
NRMRL National Risk Management Research Lab
NS not sampled
NSF NSF International
NTU nephelometric turbidity units
O&M operation and maintenance
OIP operator interface panel
ORD Office of Research and Development
ORP oxidation-reduction potential
P&ID process and instrumentation diagram
Pb lead
psi pounds per square inch
PLC programmable logic controller
PO4 orthophosphate
POE point-of-entry
PVC polyvinyl chloride
QA quality assurance
QA/QC quality assurance/quality control
QAPP Quality Assurance Project Plan
RPD relative percent difference
RFQ Request for Quotation
Sb antimony
SDWA Safe Drinking Water Act
SiO2 silica
SMCL secondary maximum contaminant level
SO4 sulfate
SOW scope of work
STMGID South Truckee Meadows General Improvement District
STS Severn Trent Services
TCLP
TDS
TO
TOC
TSS
V
Toxicity Characteristic Leaching Procedure
total dissolved solids
Task Order
total organic carbon
total suspended solids
vanadium
IX
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ACKNOWLEDGMENTS
The authors wish to extend their sincere appreciation to the staff of the Arizona Water Company (AWC)
in Phoenix and Sedona, Arizona. The primary operator, Mr. Paul Blanchard, monitored the treatment
system and collected samples from the treatment and distribution systems on a regular schedule
throughout this reporting period. This performance evaluation would not have been possible without
AWC's support and dedication.
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Section 1.0: INTRODUCTION
1.1 Background
The Safe Drinking Water Act (SOWA) mandates that U.S. Environmental Protection Agency (EPA)
identify and regulate drinking water contaminants that may have adverse human health effects and that
are known or anticipated to occur in public water supply systems. In 1975, under the SDWA, EPA
established a maximum contaminant level (MCL) for arsenic at 0.05 mg/L. Amended in 1996, the
SDWA required that EPA develop an arsenic research strategy and publish a proposal to revise the
arsenic MCL by January 2000. On January 18, 2001, EPA finalized the arsenic MCL at 0.01 mg/L (EPA,
2001). In order to clarify the implementation of the original rule, EPA revised the rule on March 25,
2003, to express the MCL as 0.010 mg/L (10 (ig/L) (EPA, 2003). The final rule requires all community
and non-transient, non-community water systems to comply with the new standard by January 23, 2006.
In October 2001, EPA announced an initiative for additional research and development of cost-effective
technologies to help small community water systems (<10,000 customers) meet the new arsenic standard
and to provide technical assistance to operators of small systems in order to reduce compliance costs. As
part of this Arsenic Rule Implementation Research Program, EPA's Office of Research and Development
(ORD) proposed a project to conduct a series of full-scale, on-site demonstrations of arsenic removal
technologies, process modifications, and engineering approaches applicable to small systems. Shortly
thereafter, an announcement was published in the Federal Register requesting water utilities interested in
participating in the first round of this EPA-sponsored demonstration program to provide information on
their water systems. In June 2002, EPA selected 17 out of 115 sites to be the host sites for the
demonstration studies. The Arizona Water Company (AWC) water system in Sedona, AZ, commonly
referred to as Valley Vista, was selected as one of the 17 Round 1 host sites for the demonstration
program.
In September 2002, EPA solicited proposals from engineering firms and vendors for cost-effective arsenic
removal treatment technologies for the 17 host sites. EPA received 70 technical proposals for the 17 host
sites, with each site receiving one to six proposals. In April 2003, an independent technical panel
reviewed the proposals and provided its recommendations to EPA on the technologies that it determined
were acceptable for the demonstration at each site. Because of funding limitations and other technical
reasons, only 12 of the 17 sites were selected for the demonstration project. Using the information
provided by the review panel, EPA, in cooperation with the host sites and the drinking water programs of
the respective states, selected one technical proposal for each site. Kinetico's adsorptive media process
using AAFS50 media was selected for the Valley Vista facility.
1.2 Treatment Technologies for Arsenic Removal
The technologies selected for the 12 Round 1 EPA arsenic removal demonstration host sites include nine
adsorptive media systems, one anion exchange system, one coagulation/filtration system, and one process
modification with iron addition. Table 1-1 summarizes the locations, technologies, vendors, and key
source water quality parameters of the 12 demonstration sites. An overview of the technology selection
and system design (Wang et al., 2004) and the associated capital costs for each site (Chen et al, 2004) are
provided on the EPA website (http://www.epa.gov/ORD/NRMRL/arsenic/ resource.htm). As of June
2006, 11 of the 12 systems have been operational, and the performance evaluation of two systems has
been completed.
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Table 1-1. Summary of Round 1 Arsenic Removal Demonstration Technologies and Source Water
Quality Parameters
Demonstration Site
WRWC (Bow), NH
Rollinsford, NH
Queen Anne's County, MD
Brown City, MI
Climax, MN
Lidgerwood, ND
Desert Sands MDWCA, NM
Nambe Pueblo, NM
Rimrock, AZ
Valley Vista, AZ
Fruitland, ID
STMGID, NV
Technology
(Media)
AM (G2)
AM (E33)
AM (E33)
AM (E33)
C/F (Macrolite)
SM
AM (E33)
AM (E33)
AM (E33)
AM (AAFS50)
IX (A300E)
AM (GFH)
Vendor
ADI
AdEdge
STS
STS
Kinetico
Kinetico
STS
AdEdge
AdEdge
Kinetico
Kinetico
USFilter
Design
Flowrate
(gpm)
70(a)
100
300
640
140
250
320
145
90(d)
37
250
350
Source Water Quality
As
(HS/L)
39
36(b)
19(b)
14(b)
39(b)
146(b)
23(b)
33
50
41
44
39
Fe
(Hg/L)
<25
46
270(c)
127(o)
546(c)
l,325(c)
39
<25
170
<25
<25
<25
PH
7.7
8.2
7.3
7.3
7.4
7.2
7.7
8.5
7.2
7.8
7.4
7.4
AM = adsorptive media process; C/F = coagulation/filtration process; IX = ion exchange process;
SM = system modification; MDWCA = Mutual Domestic Water Consumer's Association;
STMGID = South Truckee Meadows General Improvement District; WRWC = White Rock Water Company;
STS = Severn Trent Services.
(a) System reconfigured from parallel to series operation due to a reduced 40-gpm flowrate.
(b) Arsenic exists mostly as As(III).
(c) Iron exists mostly as soluble Fe(II).
(d) System reconfigured from parallel to series operation due to a reduced 30-gpm flowrate.
1.3
Project Objectives
The objective of the Round 1 arsenic demonstration program is to conduct 12 full-scale arsenic treatment
technology demonstration studies on the removal of arsenic from drinking water supplies. The specific
objectives are to:
• Evaluate the performance of the arsenic removal technologies for use on small
systems.
• Determine the required system operation and maintenance (O&M) and operator
skill levels.
• Characterize process residuals produced by the technologies.
• Determine the cost-effectiveness of the technologies.
This report summarizes the performance of the Kinetico system at Valley Vista, AZ, during the first six
months (from June 24 through December 24, 2004). The types of data collected included system
operation, water quality (both across the treatment train and in the distribution system), residuals'
characterization, and capital and preliminary O&M costs.
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Section 2.0: CONCLUSIONS
The Kinetico treatment system (FA-236-AS) with AAFS50 media was installed and operated at Valley
Vista, AZ, since June 24, 2004. Based on the information collected during the first six months of
operation, the following preliminary conclusions were made relating to the overall project objectives.
Performance of the arsenic removal technology for use on small systems
• After treating 8,200 and 16,900 bed volumes (BV) (or 1,022,000 and 2,106,000
gal) of water with an average As(V) concentration of 42 |o,g/L and pH values of
7.5 to 8.4, the effluent from the lead and lag tanks of the FA-236-AS exceeded the
10-|o,g/L arsenic breakthrough limit on July 14 and August 4, 2004, respectively.
• The arsenic adsorptive capacity of the AAFS50 media without pH adjustment was
estimated to be 0.31 mg/g of media at 10-|a,g/L arsenic breakthrough and 0.6 mg/g
of media near exhaustion.
• The spent AAFS50 media was replaced on October 25, 2004, and the second
media run began with pH adjustment of raw water at 6.7 to 6.9. As of December
15, 2004, the new media had treated 16,000 BV or 2,635,000 gal of water to 4.3
and 0.1 |o,g/L of arsenic at the effluent of the lead and lag tanks, respectively.
Therefore, pH adjustment significantly increased the media's arsenic adsorptive
capacity.
• The presence of low concentrations of iron, manganese, silica, orthophosphate,
and other ions in the water did not appear to impact arsenic removal by the
AAFS50 media.
• Little or no chlorine was consumed by the AAFS50 media.
• Arsenic concentrations in the distribution system decreased most prominently
nearest to the treatment plant (i.e., from 34.9 to 51.8 |og/L to 0.3 to 23.9 ng/L).
More distant locations from the treatment plant exhibited higher arsenic than the
treatment effluent, which was presumably due to its blending with water from
untreated wells in the distribution system.
Required system O&Mand operator skill levels
• The daily demand on the operator was typically 20 to 30 min to visually inspect
the system and record operational parameters. The FA-236-AS was equipped
with semi-automatic controls to initiate backwash and switch tank positions and
automatic controls for pH adjustment and backwash recycling.
• During the first media run, operation of the FA-236-AS did not require skills
beyond those necessary to operate the existing equipment. During the second
media run, however, pretreatment with 37-50% H2SO4 added safety precautions,
troubleshooting, complexity, and chemical handling and inventory requirements
to the system O&M.
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• Without pH adjustment, media replacement was required after 41 days of
operation (2,106,000 gal of water treated). During the second media run, results
indicated that the capacity of the media was greatly extended with pH adjustment,
and media handling requirements were thereby reduced. However, pH adjustment
increased the complexity of the system and the operator requirements.
Characteristics of process residuals produced by the technology
• The FA-236-AS was backwashed monthly, generating between 1,060 and 1,400
gal of water. Nearly 100% of the wastewater was reclaimed via a backwash
recycle system.
After passing TCLP tests, 2,200 Ib of spent media were disposed of in a state-
approved landfill as non-hazardous waste.
Technology cost
• The capital investment for the system was $228,309, including $122,544 for
equipment, $50,659 for site engineering, and $55,106 for installation.
• Based on a design capacity of 37 gpm, the capital cost was $6,171/gpm (or
$4.29/gpd), not including the cost for shed construction.
• Media replacement represented the majority of O&M cost. Changeout for both
tanks was estimated at $6,623 or $3.15/1,000 gal of water treated for the first
media run. For the second media run, acid addition significantly increased the life
of the media, but also added $0.66/1,000 gal of chemical cost to the O&M cost.
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Section 3.0: MATERIALS AND METHODS
3.1
General Project Approach
Following the predemonstration activities summarized in Table 3-1, the performance evaluation study of
the Kinetico treatment system began on June 24, 2004. Table 3-2 summarizes the types of data collected
and/or considered as part of the technology evaluation process. The overall system performance was
evaluated based on its ability to consistently remove arsenic to below the target MCL of 10 |o,g/L through
the collection of water samples across the treatment train. The reliability of the system was evaluated by
tracking the unscheduled system downtime and frequency and extent of repair and replacement. The
unscheduled downtime and repair information were recorded by the plant operator on a Repair and
Maintenance Log Sheet.
The O&M requirements were evaluated based on a combination of quantitative data and qualitative
considerations, including any pre- and/or post-treatment requirements, level of system automation,
operator skill requirements, preventative maintenance activities, frequency of chemical and/or media
handling and inventory requirements, and general knowledge needed for safety requirements and
chemical processes. The staffing requirements for the system operation were recorded on an Operator
Labor Hour Log Sheet.
The quantity of aqueous and solid residuals generated was estimated by tracking the amount of backwash
water produced during each backwash cycle and the need to replace the media upon arsenic breakthrough.
Backwash water and spent media were sampled and analyzed for chemical characteristics.
Table 3-1. Predemonstration Study Activities and Completion Dates
Activity
Introductory Meeting Held
Request for Quotation Issued to Vendor
Draft Letter of Understanding Issued
Final Letter of Understanding Issued
Vendor Quotation Received
Purchase Order Completed and Signed
Letter Report Issued
Draft Study Plan Issued
Engineering Package Submitted to ADEQ
Final Study Plan Issued
Approval to Construct Granted by ADEQ
Construction Permit Issued by County
FA-236-AS System Shipped
System Installation Completed
System Shakedown Completed
Shed Construction Begun
Shed Construction Completed
Approval of Construction Granted by ADEQ
Performance Evaluation Begun
Date
July 3 1,2003
August 4, 2003
August 13, 2003
September 16, 2003
September 25, 2003
October 16, 2003
October 17, 2003
February 4. 2004
February 17, 2004
February 24, 2004
March 23, 2004
April 12, 2004
April 23, 2004
May 7, 2004
May 11,2004
May 24, 2004
May 28, 2004
June 15, 2004
June 24, 2004
ADEQ = Arizona Department of Environmental Quality
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Table 3-2. Evaluation Objectives and Supporting Data Collection Activities
Evaluation Objective
Performance
Reliability
System O&M and Operator
Skill Requirements
Residual Management
Cost-Effectiveness
Data Collection
-Ability to consistently meet 10 (o,g/L of arsenic in effluent
-Unscheduled downtime for system
-Frequency and extent of repairs including a description of the problem, labor,
and materials' description and cost
-Pre- and post-treatment requirements
-Level of system automation for data collection and system operation
-Staffing requirements including number of operators and labor
-Task analysis of preventative maintenance including labor and number and
complexity of tasks
-Chemical handling and inventory requirements
-General knowledge needed of safety requirements and chemical processes
-Quantity of residuals generated by the treatment process
-Characteristics of the aqueous and solid residuals
-Capital cost including equipment, engineering, and installation
-O&M cost including media, chemical, and electricity usage and labor
The cost of the system was evaluated based on the capital cost per gpm (or gpd) of design capacity and
the O&M cost per 1,000 gal of water treated. This task required tracking the capital cost for the
equipment, engineering, and installation, as well as the O&M cost for media replacement and disposal,
chemical supply, electricity usage, and labor.
3.2
System O&M and Cost Data Collection
The plant operator performed daily, weekly, and monthly system O&M and data collection according to
instructions provided by Kinetico and Battelle. On a daily basis, the plant operator recorded system
operational data, such as pressure, flowrate, totalizer, and hour meter readings on a Daily System
Operation Log Sheet; checked the sodium hypochlorite (NaOCl) and sulfuric acid (H2SO4) drum levels;
and conducted visual inspections to ensure normal system operations. If any problems occurred, the plant
operator contacted the Battelle Study Lead, who determined if the vendor should be contacted for
troubleshooting. The plant operator recorded all relevant information on the Repair and Maintenance Log
Sheet. The plant operator measured water quality parameters weekly, including temperature, pH,
dissolved oxygen (DO), oxidation-reduction potential (ORP), and residual chlorine and recorded the data
on a Weekly On-Site Water Quality Parameters Log Sheet. Monthly backwash data also were recorded
on a Backwash Log Sheet.
Capital cost for the arsenic removal system consisted of equipment, site engineering, and system
installation. The O&M cost consisted of media replacement and spent media disposal, chemical and
electricity consumption, and labor. Consumption of H2SO4 and NaOCl was tracked on the Daily System
Operation Log Sheet. Electricity consumption was determined from a utility bill. Labor for various
activities, such as the routine system O&M, troubleshooting, and repair and demonstration-related work,
were tracked using an Operator Labor Hour Log Sheet. The routine O&M included activities such as
filling field logs, replenishing chemical solutions, ordering supplies, performing system inspection, and
others as recommended by Kinetico. The demonstration-related work included activities such as
performing field measurements, collecting and shipping samples, and communicating with the Battelle
Study Lead and the vendor. The demonstration-related activities were recorded, but were not used for the
cost analysis.
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3.3 Sample Collection Procedures and Schedules
To evaluate system performance, samples were collected from the wellhead, treatment plant, distribution
system, and adsorptive tank backwash. The sampling schedules and analytes for each sampling event are
listed in Table 3-3. In addition, Figure 3-1 presents a flow diagram of the treatment system including
analytes and sampling locations. Specific sampling requirements for analytical methods, sample
volumes, containers, preservation, and holding times are presented in Table 4-1 of the EPA-endorsed
Quality Assurance Project Plan (QAPP) (Battelle, 2003). The procedure for arsenic speciation is
described in Appendix A of the QAPP.
3.3.1 Source Water Sample Collection. During the initial visit to the site, source water samples
were collected in a 250-mL high-density polyethylene (HDPE) bottle containing nitric acid preservative
for metal analyses and in additional HDPE bottles containing appropriate preservatives for water quality
analyses (Table 3-3). The source water also was speciated using an arsenic speciation kit (Section 3.4.1).
The sample tap was flushed for several minutes before sampling; special care was taken to avoid
agitation, which might cause unwanted oxidation.
3.3.2 Treatment Plant Water Sample Collection. The plant operator collected water samples
across the treatment train in 250-mL HDPE bottles containing nitric acid preservative for metal analyses
and in additional HDPE bottles containing appropriate preservatives for water quality analyses. On-site
arsenic speciation was performed using arsenic speciation kits. Samples were collected weekly, on a
four-week cycle at three sample taps (i.e., at wellhead location [IN], after Tank A location [TA], and after
Tank B location [TB]) for on- and off-site analyses (Figure 3-1). For the first week of each four-week
cycle, samples were collected, speciated, and analyzed for the analytes listed in Table 3-3 for monthly
treatment plant water. For the next three weeks, samples were collected and analyzed for the analytes
listed in Table 3-3 for the weekly treatment plant water. Since November 3, 2004, the speciation
sampling was reduced from monthly to bimonthly (effective October 20, 2004) due to the absence of
As(III) in the source water. Under this revised schedule, weekly samples were collected for seven
consecutive weeks and speciation samples were collected during the eighth week. On-site measurements
also were taken after prechlorination location (AC), in addition to IN, TA, and TB, since the system was
modified to inject chlorine before adsorption on July 27, 2004.
3.3.3 Backwash Water Sample Collection. Backwash water samples were collected from the
sample tap on the backwash water effluent line. For each backwash sampling, an unfiltered sample was
collected from each tank in an unpreserved 1-gal wide-mouth HDPE bottle for water quality analyses, and
a 60-mL sample filtered on-site with 0.45-(im filters was collected in a 125-mL HDPE bottle preserved
with nitric acid for metal analyses. Analytes for the backwash samples are listed in Table 3-3.
Note that after the first six months of system operation, the backwash water sampling procedure was
modified to include collection of composite samples for total suspended solids (TSS) and total metals in
addition to pH, total dissolved solids (TDS), and soluble metals. The procedure involves connecting
tubing to the tap on the discharge line to collect a portion of the backwash water in a clean, 30-gal
container for each tank. Approximately 15-20 gal is collected in the container for the duration of the filter
tank backwash. After the backwash completes, the backwash water from each tank is mixed thoroughly
and composite samples are collected.
3.3.4 Distribution System Water Sample Collection. Samples were collected from the
distribution system to determine the impact of the arsenic treatment system on the water chemistry in the
distribution system, specifically the arsenic, lead, and copper levels. From February to March 2004, prior
to the startup of the treatment system, four sets of baseline distribution water samples were collected from
three locations within the distribution system. Following the system startup, distribution system sampling
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continued on a monthly basis at the same three locations. Ideally, the sampling locations selected would
have been the historical Lead and Copper Rule (LCR) locations served primarily by the source water
well, Point-of-Entry (POE) Well No. 2. However, because the distribution system of Valley Vista was
supplied by POE Well No. 2 and other wells, such LCR locations did not exist (Section 4.1.2). As such,
two non-LCR residences and one non-residence location served by POE Well No. 2 were used for the
distribution system sampling.
Table 3-3. Sampling Schedule and Analyses
Sample Type
Source Water
Treatment
Plant Water
Backwash
Water
Distribution
Water
Residual Solid
Sample
Locations'3'
At wellhead
At wellhead
(IN), after
Tank A (TA),
and after Tank
B (TB)
Backwash
discharge line
Two non-LCR
residences and
one non-
residence
serviced by
POE Well No.
2 and other
wells
Spent media
from Tanks A
andB
No. of
Samples
1
o
5
2
3
3 per
tank
Frequency
Once
Weekly
Monthly(c)
Monthly
Monthly(d)
Once
Analytes
As (total, soluble, and
paniculate), As(III), As(V),
total and soluble Fe, Mn,
Al, V, Mo, and Sb, Na, Ca,
Mg, Cl, F, SO4, SiO2, PO4,
TOC, turbidity, pH, and
alkalinity
On-site(b): pH, temperature,
DO, ORP, and C12 (free
and total).
Off-site: total As, Fe, Mn,
and Al, SiO2, PO4,
turbidity, and alkalinity
Same as weekly sampling
(above) plus the following
off-site: As (soluble and
paniculate), As(III), As(V),
Fe (soluble), Mn (soluble),
Al (soluble), Ca, Mg, F,
NO3, and SO4
Soluble As, Fe, Mn, and
Al, andpH, TDS, and
turbidity
Total As, Fe, Mn, Al, Cu,
and Pb, pH, and alkalinity
TCLP metals and total Al,
As, Ca, Cd, Cu, Fe, Mg,
Mn, Ni, P, Pb, Si, and Zn
Collection Date(s)
07/31/03
07/07/04, 07/14/04,
07/21/04,08/04/04,
08/11/04,08/18/04,
09/01/04,09/08/04,
09/15/04, 09/29/04,
10/13/04, 10/27/04,
11/03/04, 11/17/04,
12/01/04, 12/08/04
06/30/04, 07/28/04,
08/25/04, 09/22/04,
10/20/04, 12/15/04
08/16/04, 09/13/04,
10/12/04,11/22/04,
12/20/04
Baseline sampling:
02/10/04, 02/24/04,
03/16/04, 03/30/04
Monthly sampling:
07/28/04, 08/25/04,
09/22/04, 10/20/04,
11/17/04,12/15/04
10/25/04
(a) Abbreviation corresponds to sample location in Figure 3 - 1 .
(b) On-site measurements of samples collected at AC, in addition to IN, TA, and TB, since prechlorination began
on July 27, 2004. Chlorine measurements not performed at IN.
(c) Began bimonthly sampling effective October 20, 2004.
(d) Four baseline sampling events performed during February and March 2004 before system startup.
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Monthly
pH^, temperature^, D
As (total and soluble), As (III),
As (V), Fe (total and soluble),^
Mn (total and soluble),
Al (total and soluble), Ca, Mg, F, NO3,
SO4, SiO2, PO4, turbidity, alkalinity
INFLUENT
(POE WELL No. 2)
As (soluble), Fe (soluble),
Mn (soluble), Al (soluble),-^ ( BW
pH, TDS, turbidity
pH(a), temperature^), D
chlorine^), As (total and soluble),
As (III), As (V), Fe (total and soluble),
Mn (total and soluble),
Al (total and soluble), Ca, Mg, F, NO3,
SO4, SiO2, PO4, turbidity, alkalinity
pHW, temperature^), DO/ORP(a),
chlorine^, As (total and soluble),
As (III), As (V), Fe (total and soluble),
Mn (total and soluble),
Al (total and soluble), Ca, Mg, F, NO3,
SO4, SiO2, PO4, turbidity, alkalinity
Valley Vista, AZ
AAFS50 Technology
Design Flow: 37 gpm
Weekly
pH
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For each location, samples were collected in one unpreserved 1-L HDPE wide-mouth bottle for metal
analyses (preserved with nitric acid in the lab), and one unpreserved 250-mL HDPE bottle for water
quality analyses (Table 3-3). The samples at the two non-LCR locations were taken following an
instruction sheet developed according to the Lead and Copper Monitoring and Reporting Guidance for
Public Water Systems (EPA, 2002). The homeowners recorded the date and time of last water use before
sampling and the date and time of sample collection for calculation of the stagnation time. Sampling at
the non-residence location was performed by the plant operator with the first sample taken at the first
draw and the second sample taken after the sample tap was flushed for several minutes. All samples were
collected from a cold-water faucet that had not been used for at least 6 hr to ensure that stagnant water
was sampled.
3.3.5 Residual Solid Sample Collection. Residual solids included backwash sludge and spent
media samples. Backwash sludge samples were not collected in the initial six months of this
demonstration. Three spent media samples were collected from each tank during the first media
changeout on October 25, 2004. Spent AAFS50 media was removed from the top, middle, and bottom of
each media bed using a 5-gal wet/dry shop vacuum that was thoroughly cleaned out and disinfected. The
media from each layer was well-mixed in a clean 5-gal bucket with a small garden spade and sent to
Battelle in a 1-gal wide-mouth HDPE bottle. A portion of each sample was submitted to TCCI
Laboratories for Toxicity Characteristic Leaching Procedure (TCLP) tests. Another portion of the sample
was air dried and acid digested for metal analysis by Battelle ICP-MS Laboratory.
3.4 Sampling Logistics
3.4.1 Preparation of Arsenic Speciation Kits. The arsenic field speciation method uses an anion
exchange resin column to separate the soluble arsenic species, As(V) and As(III) (Edwards et al., 1998).
Resin columns were prepared in batches at Battelle laboratories according to the procedures detailed in
Appendix A of the EPA-endorsed QAPP (Battelle, 2003).
3.4.2 Preparation of Sampling Coolers. For each sampling event, a cooler was prepared with the
appropriate number and type of sample bottles, filters, and/or speciation kits. All sample bottles were
new and contained appropriate preservatives. Each sample bottle was affixed with a pre-printed, colored-
coded label consisting of the sample identification (ID), date and time of sample collection, collector's
name, site location, sample destination, analysis required, and preservative. The sample ID consisted of a
two-letter code for the specific water facility, the sampling date, a two-letter code for a specific sampling
location, and a one-letter code designating the arsenic speciation bottle (if necessary). The sampling
locations at the treatment plant were color-coded for easy identification (e.g., red, orange, and yellow
designated IN, TA, and TB, respectively). The labeled bottles for each sampling locations were bagged
separately and placed in the cooler.
In addition, all sampling- and shipping-related materials, such as disposable gloves, sampling instructions,
chain-of-custody forms, prepaid/addressed Federal Express air bills, and bubble wrap, were packed into
the coolers. The chain-of-custody forms and Federal Express air bills were complete except for the
operator's signature and the sample dates and times. After preparation, sample coolers were sent to the
site via Federal Express for the following week's sampling event.
3.4.3 Sample Shipping and Handling. After sample collection, samples for off-site analyses were
packed carefully in the original coolers with wet ice and shipped to Battelle. Upon receipt, sample
custodians verified that all samples indicated on the chain-of-custody forms were included and intact.
Sample IDs were checked against the chain-of-custody forms, and the samples were identified in the
laboratory sample receipt log. Discrepancies noted by the sample custodian were addressed with the plant
operator by the Battelle Study Lead.
10
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Samples for metal analyses were stored at Battelle's ICP-MS Laboratory. Samples for other water quality
analyses were packed in coolers at Battelle and picked up by a courier from Battelle's subcontract
laboratories including AAL in Columbus, OH, and TCCI Laboratories in New Lexington, OH. The
chain-of-custody forms remained with the samples from the time of preparation through analysis and final
disposition. All samples were archived by the appropriate laboratories for the respective duration of the
required hold time and disposed of properly thereafter.
3.5 Analytical Procedures
The analytical procedures described in Section 4.0 of the EPA-endorsed QAPP (Battelle, 2003) were
followed by Battelle ICP-MS Laboratory, AAL, and TCCI Laboratories. Laboratory quality assurance/
quality control (QA/QC) of all methods followed the prescribed guidelines. Data quality in terms of
precision, accuracy, method detection limits (MDL), and completeness met the criteria established in the
QAPP (i.e., relative percent difference [RPD] of 20%, percent recovery of 80-120%, and completeness of
80%). The quality assurance (QA) data associated with each analyte will be presented and evaluated in a
QA/QC Summary Report to be prepared under separate cover and to be shared with the other 11
demonstration sites included in this project.
Field measurements of pH, temperature, DO, and ORP were conducted by the plant operator using a
WTW Multi 340i handheld meter, which was calibrated for pH and DO prior to use following the
procedures provided in the user's manual. The ORP probe also was checked for accuracy by measuring
the ORP of the standard solution and comparing it to the expected value. The plant operator collected a
water sample in a clean plastic beaker and placed the WTW probe in the beaker until a stable value was
obtained. The plant operator also performed free and total chlorine measurements using Hach chlorine
test kits following instructions in the user's manual.
11
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Section 4.0: RESULTS AND DISCUSSION
4.1
Facility Description
Four wells owned by AWC supplied water to a population of 1,520 in Sedona, AZ. POE Well No. 2,
located at 315 Deer Pass Drive, with a capacity of 37 gpm, was selected forthis demonstration study.
Figure 4-1 shows the predemonstration site conditions in late July 2003.
POE Well No. 2, drilled in January 1974, has a 6-in diameter, 585-ft depth, and 565 ft of slotted screen
extending from 20 to 585 ft below ground surface (bgs). Prior to installation of the arsenic removal
system, treatment consisted of only a chlorine injection system (Figure 4-2) using a 4% NaOCl solution at
a feed rate of 0.6 gpd to reach a target chlorine residual of 0.6 mg/L (as C12). The chlorinated water then
entered the distribution system and two gravity-fed storage tanks with a total capacity of 400,000 gal.
POE Well No. 2 was controlled by level sensors in the storage tanks and operated for approximately
8 hr/day. For the purpose of this demonstration study, the well was operated 24 hr/day.
Figure 4-1. Predemonstration Site Conditions
(Right to Left: Wellhead, Piping, Hydropneumatic Tank, Electrical Panel, and Chlorine Shed)
4.1.1 Source Water Quality. Source water samples were collected from POE Well No. 2 for
analysis on July 31, 2003. The results of the source water analyses, along with those provided by the
facility to EPA for the demonstration site selection and those independently collected and analyzed by
EPA and Kinetico, are presented in Table 4-1.
12
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Figure 4-2. Existing Chlorine Injection System
Based on the July 31, 2003, sampling results, the total arsenic concentration in POE Well No. 2 was
41.0 |og/L, with arsenic existing primarily as As(V) (i.e., 93% at 37.8 (ig/L). A small amount of arsenic
also was present as particulate As (i.e., 2.8 |o,g/L) and As(III) (i.e., 0.3 ng/L). Because arsenic already
existed as As(V), which adsorbs better onto the AAFS50 media, prechlorination upstream of the treatment
process was not required.
Raw water pH values ranged from 7.6 to 7.9. Kinetico proposed to adjust the source water pH to 7.2 to
improve the media's arsenic adsorptive capacity. Therefore, pH adjustment equipment was installed at
the site, but was not used initially in order to evaluate the capacity of the media under the "as is" pH
condition.
The adsorptive capacity of AAFS50 media can be impacted by high levels of competing ions such as
silica, phosphate, and fluoride. The concentrations of these ions appeared to be low enough as not to
affect the media's adsorption of arsenic. The source water also had Fe, Mn, and Al concentrations below
detection. These values were comparable to the levels reported by all other parties. Vanadium was
measured at 16.2 (ig/L; however, its adsorption by AAFS50 has not been reported.
4.1.2 Distribution System. The distribution system was supplied by POE Well No. 2 and three
other production wells, i.e., Gulf Well, Rancho Rojo Well, and Wild House Mesa Well, with capacities of
262, 118, and 23 gpm, respectively, located within a one-mile radius. After chlorination, water from
these wells blended within the distribution system and flowed into two gravity-fed storage tanks (totaling
400,000 gal), located about half a mile downstream of POE Well No. 2. A small area of homes was
served predominantly by water produced by POE Well No. 2. Efforts were made to select locations in
this area for the distribution system sampling (Section 3.3.4).
13
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Table 4-1. POE Well No. 2 Water Quality Data
Parameter
Units
Sampling Date
pH
Total Alkalinity
Total Hardness
Chloride
Fluoride
Sulfide
Sulfate
Silica (as SiO2)
Orthophosphate
TOC
As (total)
As (soluble)
As (paniculate)
As(III)
As(V)
Fe (total)
Fe (soluble)
Al (total)
Al (soluble)
Mn (total)
Mn (soluble)
V (total)
V (soluble)
Mo (total)
Mo (soluble)
Sb (total)
Sb (soluble)
Na (total)
Ca (total)
Mg (total)
-
mg/L(a)
mg/L(a)
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
W?/L
HB/L
W?/L
HB/L
W?/L
HB/L
W?/L
^g/L
HB/L
W?/L
HB/L
W?/L
HB/L
W?/L
^g/L
HB/L
W?/L
mg/L
mg/L
mg/L
Facility
Data*'
Not specified
7.6
162
149
11.0
NS
NS
8.7
20.8
<0.065(c)
0.5
40.0
NS
NS
NS
NS
<10
NS
NS
NS
<50
NS
NS
NS
NS
NS
NS
NS
11.0
35.0
15.0
EPA
Data
10/03/02
NS
154
NS
9.7
NS
2.8
8.4
19.3
NS
NS
39.0
NS
NS
NS
NS
7.0
NS
<25
NS
0.4
NS
NS
NS
NS
NS
<25
NS
9.9
34.5
16.2
Kinetico
Data
12/02
7.9
160
160
19.8
0.1
NS
9.0
21.4
0.1
NS
40.0
NS
NS
NS
NS
<30
NS
NS
NS
NS
<10
NS
NS
NS
NS
NS
NS
10.0
35.5
17.5
Battelle
Data
07/31/03
7.7
154
172
11.0
0.2
NS
8.7
18.5
0.1
NA
41.0
38.1
2.8
0.3
37.8
<30
<30
<10
<10
0.1
O.I
16.2
15.7
0.1
O.I
O.I
0.1
11.1
39.3
18.0
AWC
Data(d)
01/94-03/02
7.6
160
149
11.3
0.1-0.2
NS
9.8
NS
NS
NS
34-47
NS
NS
NS
NS
<10
NS
NS
NS
<50
NS
NS
NS
NS
NS
<5
NS
NS
34.6
15.2
(a) AsCaCO3.
(b) Provided by AWC to EPA for demonstration site selection.
(c) Provided by EPA.
(d) Samples collected after chlorination.
NS = not sampled.
TOC = total organic carbon.
The distribution piping consisted of 6-in-diameter ductile iron and asbestos cement pipe. Service lines to
the homes were primarily copper and polyethylene pipes. Lead joints were found in some homes. Water
from the distribution system is sampled periodically for state and federal compliance with the SDWA.
Every month, three samples are collected for bacteria analysis. Under the LCR, samples have been
collected from customer taps at 14 locations every three years. The monitoring results from AWC's
Consumer Confidence Report (CCR) for 2003 are summarized in Table 4-2.
14
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Table 4-2. Distribution System Water Quality Data(a)
Parameter
Alpha emitters
Arsenic
Barium
Fluoride
Nitrate (as N)
Sodium
Sulfate(b)
Uranium
Copper(c)
Radon(b)
Unit
pCi/L
ug/L
ug/L
mg/L
mg/L
mg/L
mg/L
Mfi/L
mg/L
pCi/L
Detected Range
0.3 to 6.4
33 to 37
120 to 140
0.12 to 0.13
0.2 to 0.7
7.4 to 10
5.3
NDto 1.8
0.16
170 to 190
4.2
Source: AWC, 2004.
(a) All other constituents not detected.
(b) Parameter sampled in 1999.
(c) Parameter sampled in 2002.
ND = not detected.
Treatment Process Description
Kinetico's FA-236-AS Adsorptive Arsenic Removal System uses standard downflow filtration through
two pressure tanks arranged in series. Each tank contains a fixed bed of Alcan's Actiguard AAFS50
media, an iron-modified activated alumina (AA) medium with NSF International (NSF) Standard 61
approval for use in drinking water. This media is engineered with a proprietary additive to enhance its
arsenic adsorptive capabilities. Although the media can adsorb both As(III) and As(V), the best
performance is observed with As(V). Table 4-3 presents key physical and chemical properties of the
media.
Table 4-3. Physical and Chemical Properties of Alcan's Actiguard AAFS50 Media
Physical Properties
Parameter
Physical form
Color
Bulk density (g/cm3)
Bulk density (lb/ft3)
BET area (m2/g)
Attrition (%)
Value
Dry granular media
Brown
1.06(a)
66(a)
220
0.3
Ch emical An alysis
Constituents
A12O3 + proprietary additive
Silicon (as SiO2)
Titanium (as TiO2)
Loss on ignition
Weight %
83
0.020
0.002
17
Source: Kinetico, 2004.
(a) Reported as 0.91 g/cm3 (56.8 lb/ft3) on Alcan's Product Data Sheet.
For series operation, the media in the lead tank is generally replaced when it completely exhausts its
capacity or when the effluent from the lag tank reaches 10 |o,g/L of arsenic. The spent media in the lead
15
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tank is removed and can be disposed of as non-hazardous waste after passing EPA's Toxicity
Characteristic Leaching Procedure (TCLP) test. After loading the lead tank with new media, it is
switched to the lag position, and the lag tank is switched to the lead position. The series operation better
utilizes the arsenic removal capacity of the media when compared to parallel system design and operation.
The FA-236-AS system included a chemical feed system for pH adjustment, two pressure tanks arranged
in series, a backwash recycle system, and associated instrumentation. The system also featured schedule
80 polyvinyl chloride (PVC) solvent bonded plumbing and PVC pneumatic valves actuated by a 2-hp
compressor controlled by a programmable logic controller (PLC). Figure 4-3 is a simplified piping and
instrumentation diagram (P&ID) of the treatment system, and Figure 4-4 is a photograph of the system.
The system's design features are summarized in Table 4-4. The major processes include:
• Intake. Raw water was pumped from POE Well No. 2 at 36 gpm. The system
was equipped with a flow-limiting device to prevent filter overrun and ancillary
piping to bypass the treatment system (Figure 4-5).
• pH Adjustment. The pH control system consisted of a solenoid-driven chemical
metering pump, a 2-in in-line static mixer, an acid draw assembly with a low-level
float, an in-line pH meter, and a 55-gal drum containing 37% H2SO4 to adjust the
feed water pH to a desired setpoint (Figure 4-5). For the first media run, the pH
of the feed water was not adjusted in order to evaluate the media run length under
the "as is" pH condition.
• Chlorination. The existing chlorine feed system (Figure 4-2) was used for
chlorination. Because As(V) was the predominating species in raw water,
preoxidization of the water was not necessary. Initially, NaOCl was applied after
the adsorption tanks for disinfection purposes. After approximately one month of
system operation, algae growth was observed on the viewglass of the lead tank
(Figure 4-5). As a result, the chlorine injection point was relocated to just before
the adsorption tanks to prevent biological growth. The chlorine residual was
maintained at 0.4 to 0.6 mg/L (as C12) throughout the treatment train with a 4%
NaOCl solution.
• Adsorption. The system included two 36-in-diameter, 72-in-tall pressure tanks in
series configuration, each containing 16.7 ft3 of AAFS50 media. (Note that
although the vendor intended to load 22 ft3 of media in each tank, only 16.7 ft3
was loaded for the first media run due, in part, to a discrepancy between the
reported and actual bulk density values [Table 4-3]). Each tank had 6-in flanges
at the top and the bottom, a diffuser-style upper distributor, a hub and lateral-style
lower distributor, and two 4-in side flanges with viewglasses to allow media
observation. The adsorption tanks were constructed of fiberglass reinforced
plastic (FRP) and rated for a working pressure of 150 pounds per square inch
(psi). The tanks were skid mounted and piped to a valve rack mounted on a
polyurethane coated, welded steel frame. The system also was equipped with the
necessary valves and secondary piping to allow the tank positions to be switched
from lead to lag and vice versa at the touch of a button on the touch screen
operator interface panel (OIP).
• Backwash. Backwashing was recommended by the vendor to remove
particulates and/or media fines accumulating in the beds and prevent channeling.
Backwash was semi-automatic and was initiated by the operator when a light on
16
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the control panel indicated that a set throughput had been reached. After each
adsorptive tank was taken off-line, upflow backwash using treated water was
performed at an adjustable flowrate controlled by a diaphragm valve. The
resulting backwash water was stored in a 1,800-gal, polyethylene, conical-bottom
holding tank (Figure 4-6) equipped with high/low level sensors.
Backwash Water Recycling. Recycling capabilities were included to reclaim the
backwash water. After solids settled in the storage tank for a preset/adjustable
time period, a 1-hp vertical pump pumped the backwash water through a 25-jam
bag filter to remove any remaining suspended solids (Figure 4-6). A piping loop
reclaimed the filtered wastewater by blending it with the influent at a maximum
rate of 10% of the system flowrate.
Static Mixer
Kinetico FA-236-AS Adsorptive Arsenic Removal System
Raw Water from
Well at 50-100 psi
Chemical !
Metering I
Pumps i
Backwash
RolanwtBf Water
' H2S04|||JNaOaj
(Optional JI Existing
HH
3
[ Flow;
Filtered Water
to Storage /
Distribution by
Others
Recycle
Pump Ba9Fllter
To Adsorptive
Filter Inlet
Figure 4-3. Schematic of Kinetico's FA-236-AS Treatment System
17
-------
«•- Hi
Figure 4-4. Kinetico's FA-236-AS Treatment System on Concrete Pad
Table 4-4. Design Features for Kinetico's FA-236-AS Treatment System
Parameter
Design Value
Remarks
Pretreatment
37% H2SO4 addition (gpd)
Chlorine addition (mg/L)
5.5
not required
pH setpoint of 7.2; not used initially
Added for disinfection
Filtration
No. of tanks
Tank size (in)
Media type
Media volume (ft3/tank)
Media bed depth (in)
Peak flowrate (gpm)
EBCT (min/tank)
Hydraulic utilization (%)
Daily use rate (gpd)
Throughput to 10-|ag/L of As (gal)
Working capacity (BV)
Media life (day)
2
36 D x 72 H
Alcan AAFS50
22
37
37
4.5
100
53,280
3,074,000
18,680
56
Series configuration
7.1 ft2 cross-section
-
1 BV = 22 ft3 = 165 gal
-
-
-
24 hr/day operation
-
-
Based on 10-|ag/L As breakthrough from
lag tank
Based on capacity and utilization
Backwash
Frequency (week)
Flowrate (gpm)
Hydraulic loading rate (gpm/ft2)
Duration (min/tank)
Wastewater production (gal)
Recycle flowate (gpm)
2-3
55-60
8
10-12
1,100-1,440
3.7
-
-
-
-
-
10% of the system flow
D = diameter; H = height.
18
-------
Figure 4-5. Treatment Process Components
(Clockwise from Top: POE Well No. 2 and Treatment System Bypass Piping; Acid Addition Setup;
In-Line pH Meter; Adsorption Tanks and Lower Distributor; and Main Control Panel)
Figure 4-6. Backwash Process Components
(Clockwise from Left: 1,800-gal Holding Tank; Recycle Pump and Bag Filter;
and Backwash Flowrate Indicator and Pump Box)
19
-------
4.3 System Installation
Installation of Kinetico's FA-236-AS system was completed on May 7, 2004, with shakedown and startup
activities completed soon after. The system installation and building construction activities were carried
out by Fann Environmental in Prescott, AZ, a subcontractor to Kinetico.
4.3.1 Permitting. Engineering plans for the system permit application were prepared by the
vendor and its subcontractor. The plans included general arrangement and P&IDs of the FA-236-AS
system and drawings of a site plan, treatment plan, and piping plan. The engineering drawings were
certified by a Professional Engineer registered in the State of Arizona and submitted to ADEQ for review
and approval in mid-February 2004. The Certificate of Approval to Construct (ATC) was received on
March 23, 2004, and a construction permit was subsequently applied for and approved by Yavapai
County in mid-April 2004. Upon completion of system installation, as-built drawings were submitted to
ADEQ and Approval of Construction (AOC) was subsequently issued on June 15, 2004.
4.3.2 System Installation, Shakedown, and Startup. The FA-236-AS treatment system was
delivered to the site on April 23, 2004, after a 12 ft x 25 ft concrete pad was poured. The vendor, through
its subcontractor, performed the off-loading and installation of the system, including piping connections
to the inlet and distribution system. The mechanical installation, hydraulic testing of the unit (without
media), and media loading were completed on May 11, 2004. Battelle provided operator training on data
and sample collection from May 6-7, 2004.
4.3.3 Shed Construction. After the system was installed, a sun shed structure was built by
AWC over the treatment system in late-May (Figure 4-7). The shed structure was 12 ft x 25 ft with
a height of 11.5 ft, and was manufactured by Versa-Tube. The shed was constructed with a
galvanized steel frame anchored to the concrete pad and sheeted with 29-gauge steel with a
specially coated surface. The shed was pre-engineered with loading capacities of 90-mph for wind
and 30-lb/ft2 for snow. From late-November to mid-December 2004, the sides and ends of the shed
structure were enclosed with metal covering, exposed piping was insulated, and heat lamps were
installed within the building for added protection from cold weather.
4.4 System Operation
4.4.1 Operational Parameters. The operational parameters for the first six months of the system
operation are tabulated and attached as Appendix A. Key parameters of the first and second media runs
are summarized in Table 4-5. The first media run (without pH adjustment) began on June 24, 2004, and
ended on August 4, 2004, when the arsenic concentration in the effluent of the lag tank exceeded 10 |og/L.
Arrangements were then made to lower source water pH values to try to extend the media life (Section
4.4.2). Lowering pH values from September 17 to October 24, 2004, caused the effluent arsenic
concentrations to decrease, but not to levels below 10 |og/L. The spent media was subsequently replaced
(Section 4.4.4), and the second media run began on October 25, 2004, with pH adjustment.
The system operated for 977 hr during the first media run and 1,387 hr through the second media run,
which continued after the end of the first six months of system operation. Operating time was based on
24-hr daily operation of POE Well No. 2 and a replacement hour meter. The operational time represents a
utilization rate of 100% over the 27-week period. The faulty hour meter that was existing on-site was
replaced on November 4, 2004, to accurately reflect any system downtime due to repairs and
maintenance.
20
-------
Figure 4-7. Sun Shed Structure (Top) and Completed Enclosure (Bottom)
The average flowrate through the system during both media runs was 36 gpm, which was very close to
the design flowrate of 37 gpm. Because less media was loaded during the system startup (16.7 instead of
22 flrVtank) due to the use of an incorrect bulk density value for calculating the required media shipping
weight, the average EBCT during the first media run was reduced from the design value of 4.5 min/tank
(Table 4-4) to 3.5 min/tank (or from 9.0 to 6.9 min for both tanks). After the media changeout, the
average EBCT for the second media run was 4.6 min/tank (or 9.1 min for both tanks), which was very
close to the design value.
The pressure differential (AP) readings across each tank ranged from 4-6 psi, which were 2-3 psi higher
than the baseline AP readings measured during the system startup when hydraulic testing was performed
on the empty tanks. This extra pressure loss, caused by the media, equates to 0.9-1.3 psi/ft of media.
Further, the AP readings across each tank between two consecutive backwash events did not increase
significantly, indicating that few particulates or media fines were accumulating in the media beds.
The system throughput for the first media run at 10 |o,g/L of arsenic breakthrough in the effluent of the lag
tank without pH adjustment was approximately 2,106,000 gal (or 16,858 BV) based on the treatment
system totalizer. By the end of the first six months of system operation, the throughput for the second
media run with pH adjustment already surpassed that of the first media run at 3,000,000 gal (or
18,230 BV).
21
-------
Table 4-5. Operation of FA-236-AS Treatment System
Parameter
First Media Run
without pH Adjustment
06/24/04-08/04/04(a)
Second Media Run
with pH Adjustment
10/25/04-12/22/04
-------
4.4.3 Backwash. The FA-236-AS system was backwashed nine times during the first six months
of operation. A set throughput was used to alert the operator to manually initiate system backwash. The
throughput was initially set at 340,000 gal, increased to 740,000 gal, and then again increased to
1,400,000 gal (Table 4-6), because no significant pressure buildup occurred during system operation.
Backwash was then performed about every 28 days except when it was required to adjust the operation of
the recycle pump on September 18, 2004, and for media changeout on October 25, 2004.
During system startup, the backwash duration was increased from the design value of 10-12 min/tank to
20 min/tank as the maximum backwash flowrate attainable was 36 gpm or 5 gpm/ft2, which was lower
than the design value of 55-60 gpm or 8 gpm/ft2. With this modification, the volumes of wastewater
generated during each event ranged from 1,060 to 1,400 gal, consistent with the target of 1,100 to 1,440
gal. Backwash water handling is discussed in Section 4.4.5. The low AP readings indicated that the
reduced hydraulic loading rate was adequate to fully backwash the tanks.
Table 4-6. Summary of Backwash Events
Date
07/02/04
07/19/04
08/16/04
09/13/04
09/18/04
10/12/04
10/25/04
11/22/04
12/20/04
Total
Backwash
Flowrate
gpm
27-29
34-35
34
33-34
34
35
35
36
35
Backwash
Duration00
min
40
40
40
40
40
40
40
40
40
Wastewater
Generated
gal
,112
,060
,362
,354
,352
,400
,200
,249
,350
11,439
Backwash
Setpoint
gal
340,000
740,000
1,400,000
1,400,000
1,400,000
1,400,000
1,400,000
1,400,000
1,400,000
Time between
Backwash Events
day
8(b)
17
28
28
5(o)
24
13(d)
28
28
(a) For both tanks.
(b) First backwash since system startup on 06/24/04.
(c) Backwash initiated to adjust recycle pump operation.
(d) Backwash initiated after media changeout.
4.4.4 Media Changeout. The first media changeout was performed by Fann Environmental on
October 25, 2004. Before spent media removal, the heights of the freeboard, as measured from the flange
at the top of the tanks to the media surface, were 39.5 in for Tank A and 40.5 in for Tank B. These
measurements are comparable to the initial heights of the freeboard measured during shakedown in May
2004 (i.e., 39.3 in for both tanks). The spent media was sampled and removed from each tank as
described in Section 3.3.5 after the tanks were drained and pumps and isolation valves were turned off.
The tank walls were rinsed and any remaining media was removed from the bottom of the tanks. Each
tank was then filled one-third full with water before adding 1,450 Ib or 22 ft3 of virgin AAFS50 media, as
specified in the original design, by pouring the media through a large funnel from the top of the tank. The
tanks were completely filled with water, and the media was allowed to soak for at least 1 hr. After the
media was properly backwashed, freeboard measurements were obtained (i.e., 27.3 in for both tanks), and
the system was returned to service.
4.4.5 Residual Management. Backwash recycling capabilities (Section 4.2) enabled the system to
reclaim nearly 100% of the wastewater produced by blending it with source water at 2-3 gpm. Although
it was lower than the design value of 3.7 gpm, the recycle flowrate was not increased as it wasn't critical
23
-------
to the system performance. The only residual produced by operation of the treatment system was 2,200 Ib
of spent media. Because the spent media passed TCLP tests (Section 4.5.4), it was disposed of by Waste
Management, Inc. at Gray Wolf Landfill in Dewey, AZ.
4.4.6 Reliability and Simplicity of Operation. Relatively rapid arsenic breakthrough during the
first media run (Section 4.5.1) and pH adjustment (Section 4.4.2) were the primary sources of concern
during this reporting period. Other O&M issues encountered were problems with the chlorine injector,
the backwash recycle pump, and a broken inlet bag filter pressure gauge due to unusually cold weather in
late November 2005. A minimal amount of unscheduled downtime was necessary to repair system
components as discussed above. Scheduled downtime for the first media changeout was 12 hr. The total
amount of unscheduled and scheduled downtime was no more than 1%.
Pre- and Post-Treatment Requirements. For disinfection purposes, NaOCl was initially injected
downstream of the system to provide a chlorine residual of 0.4 to 0.5 mg/L (as C12) through the
distribution system. On July 27, 2004, after biological growth was observed in the lead tank, the chlorine
injection point was moved upstream to the system to prevent biological growth and provide disinfection
throughout the treatment system.
The demonstration study commenced without raw water pH adjustment to evaluate the media life under
the unaltered pH condition. After this condition was evaluated during the first media run, acid addition
with a 37-50% H2SO4 solution began on September 17, 2004, to improve the performance of the media by
adjusting the raw water pH to 7.2.
System Automation. The FA-236-AS was semi-automatically controlled by the PLC in the central
control panel. The control panel contained a touch screen OIP that facilitated monitoring of system
parameters, changing of system setpoints, and checking the alarm status. Based on the throughput
setpoint, the control panel indicated when a backwash or media changeout was needed. The OIP enabled
the operator to initiate the automatic backwash sequence and switch tank positions from lead to lag and
vice versa. Additional automated features included pH adjustment and backwash water recycling. The
acid pump was a paced pump, which was controlled by the pH transmitter based on the pH of the water
entering the adsorption tanks. Operation of the backwash recycle pump was controlled using level
sensors within the 1,800-gal reclaim tank.
Operator Skill Requirements. Under normal operating conditions, the skill requirements to operate the
treatment system were minimal. The daily demand on the operator was typically 20-30 min for visual
inspection of the system and recording of operational parameters on the log sheets. In Arizona, operator
certifications are classified by grade on a scale of 1 (least complex) to 4 (most complex) according to
facility type, size, complexity, and population served (ADEQ, 2005). The primary operator was Water
Distribution Grade 4 and Water Treatment Grade 4 certified. After receiving proper training by the
vendor during the system startup, the operator understood the PLC, knew how to use the OIP, and was
able to work with the vendor to trouble shoot and perform minor on-site repairs.
Preventative Maintenance Activities. Preventative maintenance tasks recommended by the vendor
included daily recording of pressures, flows, chemical drum levels, and visually checking for leaks,
overheating components, and the manual valves' positions. The vendor also recommended weekly
checking for trends in the recorded data which might indicate a decline in system performance, and
monthly cleaning and calibrating of the in-line pH probe, initiating backwash, replacing bag filters, and
checking the pumps' lubricant levels.
Chemical/Media Handling and Inventory Requirements. The facility coordinated the NaOCl solution
supply and refilled the drum on an as-needed basis. H2SO4 was supplied in 55-gal drums by Univar's
24
-------
Phoenix, AZ, facility. Generally, two drums were shipped at a time and replacement drums were ordered
once the second drum was opened; each drum typically lasted for 2-3 weeks. Univar did not offer
refundable drum deposits for 50% H2SO4, so Fann Environmental was contracted by Battelle to neutralize
and dispose of empty drums. Although the chemical handling requirement was increased, results through
the second media run indicated that the arsenic removal capacity of the media was greatly extended with
pH adjustment, and media handling requirements were, thereby, reduced. Without pH adjustment, media
replacement was required after 41 days of system operation.
4.5 System Performance
4.5.1 Treatment Plant Sampling. The treatment plant water was sampled on 23 occasions
(including two duplicate events) during the first six months, with field speciation performed six times.
Table 4-7 summarizes the results of As, Fe, Mn, and Al at IN, TA, and TB. On-site water quality
measurements, including pH, temperature, DO, and ORP, were performed at IN, AC, TA, and TB.
Chlorine residuals also were measured at AC, TA, and TB since prechlorination began on July 27, 2004.
Table 4-8 summarizes the results of the other water quality parameters at IN, AC, TA, and TB during the
first six months with alkalinity, pH, and sulfate presented both before and after acid addition began.
Appendix B contains a complete set of the analytical results through the first six months of system
operation. The results of the water samples collected throughout the treatment plant are discussed below.
Arsenic. Total arsenic concentrations in raw water ranged from 23.5 to 47.6 |o,g/L and averaged
40.0 |o,g/L, with As(V) being the predominating species (Table 4-7). Only trace amounts of particulate As
and As(III) existed. The arsenic concentrations measured during this period were consistent with those in
the raw water sample collected on July 31, 2003 (Table 4-1).
Arsenic results for the Kinetico system are shown in Figure 4-8 with total arsenic concentrations at IN,
TA (after the lead tank), and TB (after the lag tank) along with the average pH values measured at TA and
TB plotted against the sample collection dates. (Recall that the system was operating at a relatively
constant 36-gpm flowrate around the clock.) Without pH adjustment, arsenic concentrations at TA
exceeded 10 (ig/L (i.e., 13.3 (ig/L) at about 8,200 BV, less than three weeks after the system startup.
(Note that BV was calculated based on 16.7 ft3 [125 gal] of media in the lead tank.) After another three
weeks (on August 4, 2004), arsenic concentrations at TB also exceeded 10 (ig/L (i.e., 10.7 (ig/L) at about
16,900 BV. It is presumed that the relatively high pH values of the influent to the adsorption tanks
(ranging from 7.7 to 7.9; Table 4-8) and the shorter EBCTs (Section 4.4.1) might have contributed to the
early arsenic breakthrough.
Based on Figure 4-8, the adsorptive capacity of the AAFS50 media without pH adjustment was estimated
to be 0.31 mg of As/g of media at 10-(ig/L arsenic breakthrough, which is equivalent to that obtained
from a rapid small scale column test conducted on-site by Arizona State University (Westerhoff et al.,
2006). After 10-(ig/L arsenic breakthrough, arsenic concentrations at TA continued to rise and almost
reached the levels of raw water at about 34,000 BV just before the commencement of pH adjustment on
September 17, 2004. At this point of near exhaustion, the adsorptive capacity of the AAFS50 media was
estimated to be 0.6 mg of As/g of media. The adsorptive capacities were calculated by dividing the
arsenic mass represented by the area between the IN and TA curves (i.e., 152 g at 10-|o,g/L breakthrough
and 301 g near exhaustion) by the amount of media in the tank (i.e., 1,100 Ib).
On September 17, 2004, pH adjustment of raw water began so that the effect of lowering pH from about
7.8 to 6.8 on arsenic breakthrough and media life might be examined. As shown in Figure 4-8, although
it was effective at reducing arsenic concentrations (e.g., from 33.5 to 20.2 (ig/L at TA and from 26.0 to
12.3 (ig/L at TB on September 29, 2004), the acid addition was not able to bring the effluent to below
10 (ig/L. The acid addition was temporarily interrupted during October 13 to 18, 2004, whereupon the
25
-------
Table 4-7. Summary of Arsenic, Iron, Manganese, and Aluminum Results (06/24/04-12/22/04)
Parameter
(Figure, if any)
As (total)
(Figure 4-8)
As (soluble)
As (paniculate)
As(III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
Sampling
Location
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
Sample
Count
25
6
6
6
6
6
6
6
6
6
6
6
6
6
6
25
25
25
6
6
6
25
25
25
6
6
6
23
23
23
5
5
5
Concentration (n-g/L)
Minimum
23.5
NM
NM
39.6
NM
NM
<0.1
NM
NM
0.4
NM
NM
38.6
NM
NM
<25
<25
<25
<25
<25
<25
<0.1
<0.1
<0.1
0.1
0.1
0.1
<10
<10
<10
<10
<10
<10
Maximum
47.6
NM
NM
47.4
NM
NM
0.8
NM
NM
1.0
NM
NM
46.7
NM
NM
144
34.0
52.7
<25
25.0
<25
60.2
2.4
19.2
0.3
2.4
2.8
22.0
29.1
23.7
<10
<10
13.0
Average
40.0
NM
NM
42.4
NM
NM
0.2
NM
NM
0.6
NM
NM
41.9
NM
NM
18.5
14.0
16.0
<25
14.6
<25
2.7
0.3
1.2
0.2
0.5
0.6
5.7
7.3
7.7
<10
<10
6.6
Standard
Deviation
5.4
NM
NM
3.8
NM
NM
0.3
NM
NM
0.2
NM
NM
3.8
NM
NM
26.4
5.2
10.1
0.0
5.1
0.0
12.0
0.5
3.8
0.1
0.9
1.1
3.6
5.9
4.9
0.0
0.0
3.6
NM = not meaningful for data related to breakthrough curves. See Appendix B for analytical results.
One-half of detection limit used for nondetect results for calculations.
Duplicate samples included for calculations.
arsenic concentration at TA returned immediately to that of the raw water. After acid addition resumed
on October 19, 2004, the arsenic concentration at TA again decreased. Although less significant, similar
observations were made at TB, with arsenic concentrations swinging up and down based on different
influent pH values. Lower effluent concentrations at lower influent pH values suggested an increased
media capacity for arsenic, thus extending the media life as would be expected.
26
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Table 4-8. Summary of Other Water Quality Parameter Results (06/24/04-12/22/04)
Parameter
(Figure, if any)
Alkarinity(a)
(as CaCO3)
(Figure 4-9)
Fluoride
Sulfate(a)
(Figure 4-9)
Orthophosphate
(as PO4)
Silica (as SiO2)
(Figure 4-10)
Nitrate (as N)
Turbidity
pH(a)
(Figures 4-8 and 4-
9)
Temperature
Dissolved Oxygen
ORpW
Free Chlorine(b) (as
C12)
Total Chlorine(b)
(as C12)
Sampling
Location
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
TA
TB
IN
AC
TA
TB
IN
AC
TA
TB
IN
AC
TA
TB
IN
AC
TA
TB
AC
TA
TB
AC
TA
TB
Unit
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
NTU
NTU
NTU
s.u.
s.u.
s.u.
s.u.
°c
°c
°c
°c
mg/L
mg/L
mg/L
mg/L
mV
mV
mV
mV
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Sample
Count
25
13/11
13/11
6
6
6
6
3/3
3/3
25
25
25
25
25
25
6
6
6
25
25
25
23
8/10
12/10
12/10
23
19
23
23
23
19
23
23
19
19
19
19
19
19
19
19
18
19
Minimum
138
156/114
151/114
0.1
<0.1
0.1
6.8
8.1/31
8.1/31
O.06
0.06
0.06
18.2
NM
NM
0.8
0.7
O.04
0.1
O.I
O.I
7.5
7.7/6.7
7.7/6.7
7.6/6.7
18.1
19.0
18.5
18.8
5.3
5.1
5.1
5.2
179
560
603
604
0.3
0.3
0.3
0.3
0.4
0.4
Maximum
168
169/128
167/126
0.1
0.1
0.1
8.4
8.4/50
9.4/45
O.10
0.10
0.10
19.5
NM
NM
1.0
1.0
0.9
0.6
0.5
0.7
8.4
7.9/6.9
7.9/6.9
7.8/6.9
25.0
21.1
22.4
23.3
6.5
6.5
6.1
6.4
248
754
727
751
0.9
0.8
0.8
0.9
0.8
0.8
Average
158
161/122
158/122
0.1
0.1
0.1
7.9
8.3/39
8.6/37
0.0
0.0
0.0
18.8
NM
NM
0.8
0.8
0.7
0.2
0.2
0.2
7.8
7.8/6.8
7.7/6.8
7.7/6.8
20.3
20.1
20.2
20.3
6.0
5.8
5.7
5.8
207
635
657
668
0.5
0.4
0.4
0.5
0.5
0.5
Standard
Deviation
6.5
4.1/3.9
4.3/3.8
0.0
0.0
0.0
0.6
0.2/9.7
0.7/7.1
0.0
0.0
0.0
0.4
NM
NM
0.1
0.1
0.3
0.1
0.1
0.2
0.2
0.1/0.1
0.1/0.1
0.1/0.1
1.4
0.6
0.8
0.9
0.3
0.3
0.3
0.3
19
63
49
52
0.2
0.1
0.1
0.2
0.1
0.1
27
-------
Table 4-8. Summary of Other Water Quality Parameter Results (06/24/04-12/22/04) (Continued)
Parameter
(Figure, if any)
Total Hardness
(as CaCO3)
Ca Hardness
(as CaCO3)
Mg Hardness
(as CaCO3)
Sampling
Location
IN
TA
TB
IN
TA
TB
IN
TA
TB
Unit
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Sample
Count
6
6
6
6
6
6
6
6
6
Minimum
136
140
136
66.2
69.6
68.3
69.6
70.4
67.7
Maximum
181
178
180
105
101
101
86.0
88.4
85.4
Average
164
162
163
88.9
87.2
87.9
75.5
74.8
74.6
Standard
Deviation
18.1
14.7
15.6
13.6
11.0
11.8
6.5
7.2
6.3
(a) Values before (06/24/04-09/16/04)/after (09/17/04-12/22/04) pH adjustment. Data from 10/13/04 not included
as pH adjustment was temporarily interrupted.
(b) Measurements since prechlorination began on July 27, 2004.
NM = not meaningful for data related to breakthrough curves. See Appendix B for analytical results.
One-half of detection limit used for nondetect results for calculations.
Duplicate samples included for calculations.
50
10/13/04 &
10/19/04: pH
adjustment
turned off and
resumed,
respectively
6.0
06/24/04
07/24/04
08/23/04
09/22/04
10/22/04
11/21/04
12/21/04
Note: One outlier (i.e., 37.8 ug/L on 10/27/04 at TA) not plotted.
-•-
Inlet
-•-
Tank
A
-*-
TankB
-K—
Treatment pH
Figure 4-8. Total Arsenic Concentrations and Treatment pH over Time
28
-------
The second media run with pH adjustment began on October 25, 2004. As of December 15, 2004, the
new AAFS50 media, with influent pH values reduced to an average value of 6.8, had treated
approximately 16,000 BV (2,635,000 gal) of water, which was 86% of the vendor-estimated working
capacity (i.e., 18,680 BV [Table 4-4]). (Note that BV was calculated based on 22 ft3 [165 gal] of media
in the lead tank.) Total arsenic concentrations measured at TA and TB were 4.3 and 0.1 (ig/L,
respectively, as shown in Figure 4-8. The arsenic breakthrough of this media run will be further
discussed in the final performance evaluation report.
Iron, Manganese, and Aluminum. Concentrations of total and soluble Fe and Mn were mostly near
and/or below the respective detection limits throughout the treatment system except one measurement on
September 22, 2004 (i.e., 19.2 |o,g/L Mn at TB) and two measurements on October 13, 2004 (i.e.,
144 |o,g/L Fe and 60.2 |o,g/L Mn at IN). Total Al concentrations were mostly <10 ng/L, but were observed
up to 22.0, 29.1, and 23.7 |o,g/L at IN, TA, and TB, respectively. Although this indicates some Al might
have leached from the AAFS50 media, all concentrations were below the secondary maximum
contaminant level (SMCL) of 0.05 to 0.2 mg/L.
Alkalinity, Sulfate, andpH. Average raw water alkalinity, sulfate, and pH values were 158 mg/L (as
CaCO3), 7.9 mg/L, and 7.8, respectively (Table 4-8). These values remained consistent throughout the
treatment train until pH adjustment began on September 17, 2004. Thereafter, 37-50% H2SO4, consumed
at a rate of approximately 0.06 gal/1,000 gal of water treated, reduced pH values to 6.7-6.9, decreased
average alkalinity levels to 122 mg/L (as CaCO3), and increased average sulfate levels to 39 mg/L at TA
(Table 4-8 and Figure 4-9). Concentrations at TA were similar to those measured at TB, indicating that
the media had little or no effect on these analytes. It was clear that pH was the single most influential
factor affecting the arsenic adsorptive capacity of the media, as evident by the arsenic breakthrough
curves with and without pH adjustment shown in Figure 4-8.
The consumption rate of 37-50% H2SO4was equivalent to that derived from a theoretical calculation
described by Rubel (2003) (Table 4-9). The actual alkalinity reduction (i.e., 36 mg/L [as CaCO3]) and
sulfate increase (i.e., 31 mg/L) also were similar to the theoretical values of 45 mg/L (as CaCO3) and
44 mg/L, respectively, as shown in Table 4-9.
Fluoride, Orthophosphate, and Nitrate. Fluoride and orthophosphate concentrations were near and/or
below the detection limit for all samples. The nitrate results also remained fairly consistent throughout
the treatment train, appearing unaffected by the prechlorination, acid addition, and media during the first
six months.
Silica. Silica removal was observed immediately after the initial system startup and media changeout
when the media was fresh (Figure 4-10). Within a couple of months, silica levels in the effluent of the
adsorption tanks approached influent concentrations. After pH adjustment began on September 17, 2004,
silica levels in the treatment tanks' effluent exceeded influent concentrations, presumably because silica
was desorbed from the AAFS50 media at lower pH values. The effect of pH on silica removal was
observed again at the end of the first media run when acid addition was temporarily interrupted.
DO, ORP, and Chlorine. Raw water from POE Well No. 2 was rather oxidizing as indicated by the DO
concentrations ranging from 5.3 to 6.5 mg/L and ORP readings ranging from 179 to 248 millivolts (mV).
Thus, it explains why little or no As(III) was present in raw water. As a result of prechlorination, the
ORP readings at AC, TA, and TB increased significantly to the range of 560 to 754 mV. The chlorine
residuals measured at TA and TB were comparable to those measured at AC, indicating little or no
chlorine consumption through the adsorption tanks.
29
-------
Alkalinity Values throughout the Treatment System
< 120
9/17/04 pH
began
6/24/04 7/15/04 8/5/04 8/26/04 9/16/04 10/7/04 10/28/04 11/18/04 12/9/04
Sulfate Values throughout the Treatment System
6/24/04 7/15/04 8/5/04 8/26/04 9/16/04 10/7/04 10/28/04 11/18/04 12/9/04
pH Values throughout the Treatment System
6/24/04 7/15/04 8/5/04 8/26/04 9/16/04 10/7/04
Figure 4-9. Alkalinity, Sulfate, and pH Values over Time
30
-------
Table 4-9. Theoretical Calculation of Acid Consumption for pH Adjustment
Parameter
PH
Alkalinity
Free CO2
Alkalinity Reduction
Acid Required
H2SO4 Required
50% H2SO4 Required
50% H2SO4 Required
Unit
S.U.
mg/L(a)
mg/L
mg/L(a)
meq/L
mg/L
lb/1,000 gal
gal/1,000 gal
Raw Water
Value
7.9
158
4
pH Adjusted
Value
6.8
113
43
45
0.9
44
0.74
0.06
(a) AsCaCO3
24
20 -
— 16
c
o
I
0)
u
c
o
o 12
I
55
10/13/04 &
10/19/04: pH
adjustment
turned off and
resumed,
respectively
06/24/04
07/24/04
08/23/04
09/22/04
10/22/04
11/21/04
12/21/04
Inlet -B-Tank A -A—Tank B
Figure 4-10. Silica Concentrations over Time
Hardness. Total hardness ranged from 136 to 181 mg/L (as CaCO3) (Table 4-8), consisting of
approximately 54% Ca hardness and 46% Mg hardness. Hardness did not appear to be affected by the
treatment process or acid addition.
4.5.2 Backwash Water Sampling. The analytical results of the five sets of backwash water
samples collected are summarized in Table 4-10. (Note that since the first six months of system
operation, the backwash water sampling procedure has been modified [Section 3.3.3].) Because treated
water was used for backwash, the pH values of the backwash water were similar to those of the treated
water. Since October 12, 2004, the pH values of the backwash water were lower than previous results
due to pH adjustment of the raw water beginning on September 17, 2004.
31
-------
The soluble arsenic concentrations in the backwash water from each tank were higher than those in the
treated water used for backwash. Data also show that the backwash water from Tank A contained higher
soluble arsenic levels than Tank B. After media changeout on October 25, 2004, soluble arsenic
concentrations in the backwash water were significantly less than previous results presumably due to the
improved quality of the treated water. The soluble arsenic concentrations in the backwash water were
considerably higher than the treated water results possibly due to desorption from the media or blending
of the treated water used for backwash in the distribution system with other untreated sources. Turbidity
readings of Tank A were higher than those of Tank B, most likely because the lead tank removed the
majority of the particulates from raw water. The sampling events did not show significant differences for
soluble Fe, Mn, and Al concentrations between the two tanks.
Table 4-10. Backwash Water Sampling Results
Sampling
Event
No.
1
2
o
6
4
5
Date
08/16/04
09/13/04
10/12/04(a)
H/22/04^
12/20/04
Tank A
M
S.U.
7.6
7.7
7.0
7.2
6.9
Turbidity
NTU
22
30
230
79
38
!/5
e
mg/L
464
206
224
252
292
Soluble As
Hg/L
36.5
36.5
34.5
27.0
25.0
Soluble Fe
Hg/L
<25
<25
<25
<25
<25
Soluble Mn
Hg/L
0.2
0.2
0.3
1.0
0.3
Soluble Al
Hg/L
13.2
<10
<10
<10
14.2
TankB
M
8.
S.U.
7.7
7.7
7.2
7.1
6.8
Turbidity
NTU
4.2
2.6
5.2
18
6.6
!/5
e
mg/L
822
248
216
210
664
Soluble As
Hg/L
24.5
30.9
19.0
0.3
1.5
Soluble Fe
Hg/L
<25
<25
<25
<25
<25
Soluble Mn
Hg/L
0.1
0.1
<0.1
0.2
0.2
Soluble Al
Hg/L
18.2
11.1
<10
11.6
14.5
(a) pH adjustment began 09/17/04.
(b) Media changeout occurred 10/25/04.
4.5.3 Distribution System Water Sampling. The results of the distribution system sampling are
summarized in Table 4-11. The most noticeable change in the distribution samples since the system began
operation was a decrease in arsenic concentrations. Baseline arsenic concentrations averaged 41.9, 39.2,
and 44.5 |og/L for the first draw samples at DS1, DS2, and DS3, respectively, and 43.0 |o,g/L for flushed
samples at DS3. Since the performance evaluation began and until the first media changeout, arsenic
concentrations averaged 31.6, 31.7, and 15.7 |og/L for first draw samples at DS1, DS2, andDS3,
respectively, and 16.0 |o,g/L for flushed samples at DS3. Arsenic levels were reduced most prominently at
DS3 where concentrations were 5.5 and 5.4 |o,g/L for the first event after system startup and 0.3 and 0.2
|o,g/L for the the two events after media replacement for the first draw and flushed samples, respectively.
Throughout the first six months, arsenic concentrations at DS1 and DS2 were higher than those in the
system effluent, presumably due to the blending of the treated water (supplied by POE Well No. 2) with
untreated water from other wells which also contained arsenic. Arsenic concentrations at DS3 were more
representative of those reported at the system effluent due to the location's close proximity to the
treatment system.
Lead concentrations ranged from <0.1 to 5.2 |o,g/L, with no exceedances over the action level of 15 |o,g/L.
Copper concentrations ranged from 0.7 to 435 |o,g/L, with no samples exceeding the 1,300 |o,g/L action
level. Due to the blending of water from untreated wells at locations DS1 and DS2, it was inconclusive
whether the Pb or Cu concentrations in the distribution system had been affected by the arsenic treatment
32
-------
Table 4-11. Distribution System Sampling Results
Sampling
Event
Date
02/10/04
<
mg/L
153
160
158
155
151
160
126
123
131
110
1/3
Mg/L
46.9
51.8
44.4
34.9
5.5
23.9
13.7
19.5
0.3
0.3
£
Mg/L
845
<25
<25
<25
<25
<25
<25
<25
<25
40.6
•
Mg/L
6.6
1.8
1.4
1.2
<0.1
0.1
1.0
0.3
1.9
0.5
*
Mg/L
<10
<10
<10
<10
<10
<10
10.2
14.8
<10
<10
—
Mg/L
5.2
0.5
2.1
0.5
0.7
1.4
0.8
0.8
1.6
2.5
O
Mg/L
26.9
3.5
23.0
3.0
8.6
17.4
4.5
24.6
11.3
10.5
Flushed'0'
e.
S.U.
NS
7.6
7.5
7.6
7.7
7.7
7.0
7.1
7.0
7.3
£>
<
mg/L
NS
152
158
157
159
148
126
131
127
110
1/3
Mg/L
NS
50.6
43.8
34.6
5.4
24.0
16.2
18.5
0.2
0.2
£
Mg/L
NS
<25
<25
<25
<25
<25
<25
65.3
<25
<25
•
Mg/L
NS
1.6
1.2
1.2
<0.1
0.1
<0.1
0.6
0.3
0.4
*
Mg/L
NS
<10
<10
<10
<10
<10
<10
<10
<10
<10
—
Mg/L
NS
0.1
0.2
0.1
0.2
0.2
0.3
<0.1
0.9
0.8
O
Mg/L
NS
0.7
1.5
1.0
1.8
1.0
3.0
1.0
5.5
4.3
(a) Samples collected from a neighboring home on 02/10/04.
(b) Location closest to treatment system; effects from other wells minimized.
(c) Stagnation times not available for flushed location.
(d) As CaCO3.
(e) Baseline sampling event.
(f) pH adjustment began 09/17/04.
(g) Media changeout occurred 10/25/04.
Lead action level = 15 ug/L; copper action level = 1.3 mg/L
NA = data not available.
OJ
OJ
-------
system. However, Pb and Cu concentrations at DS3 did not appear to be significantly impacted,
presumably indicating minimal impacts throughout the distribution system.
Measured pH values were 7.2-8.2 and 6.8-7.4 before and after acid addition began on September 17,
2004, respectively. Alkalinity levels decreased correspondingly from 139-160 to 110-152 mg/L (as
CaCO3). Iron concentrations ranged from <25 to 71 |o,g/L, except for the first baseline sample at DS3,
with concentrations in the majority of the samples at <25 |o,g/L. The concentrations of Mn in the
distribution samples were <7.0 |o,g/L. Aluminum concentrations were <10 ng/L except for four
exceedances slightly over 10 |og/L.
4.5.4 Spent Media Sampling. On October 25, 2004, spent media samples were collected for total
metals and TCLP analysis (Section 3.3.5). The results, as presented in Table 4-12, indicate that the
AAFS50 media removed As, Zn, Cu, Pb, and P as water passed downward through Tank A, followed by
Tank B, as noted by the decreasing concentrations of the metals removed. Average arsenic
concentrations throughout Tanks A and B were 0.57 and 0.39 mg/g of media, respectively, which is
equivalent to a combined mass of 474 g of As on 2,200 Ib of media. Compared to the mass removed from
the influent water through October 20, 2004 (i.e., 668 g of As), 71% recovery was achieved (Table 4-13).
The TCLP results indicated that the media was non-hazardous and could be disposed of in a standard
landfill (i.e., Gray Wolf Landfill in Dewey, AZ). Only barium was detected at 1.43 and 1.63 mg/L in
Tank A and Tank B, respectively (Table 4-14).
Table 4-12. Spent Media Total Metal Analysis
Analyte
Unit
Tank A (Top)
Tank A (Middle)
Tank A (Bottom)
Tank B (Top)
Tank B (Middle)
Tank B (Bottom)
Mg
M£/g
340
276
265
251
266
261
Al
mg/g
111
86.4
101
90.5
110
124
Si
M£/g
36.4
40.7
32.3
29.9
35.9
32.5
P
M.g/g
563
498
411
283
249
175
Ca
mg/g
1.7
1.6
1.6
1.6
1.6
1.7
Fe
mg/g
16.0
14.9
15.1
14.3
15.4
17.5
Mn
MS/g
95.8
86.2
77.0
120.1
116.2
123.8
Ni
M.g/g
1.2
1.1
1.1
1.2
1.3
1.4
Cu
MS/g
4.2
4.1
3.2
1.7
1.5
1.1
Zn
M.g/g
143
146
121
81.9
67.2
52.1
As
M.g/g
638
531
528
410
396
349
Cd
M.g/g
0.03
0.04
0.04
0.06
0.03
0.03
Pb
MS/g
1.1
0.8
0.6
0.5
0.4
0.5
Note: Average compositions calculated from triplicate analyses.
Table 4-13. Summary of Arsenic Removed by AAFS50 Media
Duration
Source
Unit
Tank A
TankB
Combined
06/24/04-09/15/04
-------
4.6
System Cost
The cost of the system was evaluated based on the capital cost per gpm (or gpd) of design capacity and
the O&M cost per 1,000 gal of water treated. This required tracking capital cost for the equipment, site
engineering, and installation and the O&M cost for media replacement and disposal, chemical supply,
electricity consumption, and labor. The shed construction cost was not included in the capital cost
because it was outside of the scope of this demonstration project and was funded separately by AWC.
Table 4-14. TCLP Results of Spent Media
Parameter
Arsenic
Barium
Cadmium
Chrome
Lead
Mercury
Selenium
Silver
Concentration (mg/L)
Tank A
<0.05
1.43
<0.05
<0.05
<0.1
O.003
<0.3
<0.05
TankB
<0.05
1.63
<0.05
<0.05
<0.1
<0.003
<0.3
<0.05
4.6.1 Capital Cost. The capital investment for the equipment, site engineering, and installation
was $228,309 (Table 4-15). The equipment cost was $122,544 (or 54% of the total capital investment),
which included the cost for two skid-mounted pressure tanks, 44 ft3 (33.4 ft3 actually delivered [Section
4.2]) of AAFS50 media, instrumentation and controls, a backwash recycle system, a chemical injection
system, labor (for operator training, technical support, and system shakedown), warranty, and
miscellaneous materials and supplies. The AAFS50 media price was quoted at $85.50/ft3 (or $1.30/lb) at
the beginning of the study, but has since increased to $98.86/ft3 (or $1.50/lb).
The engineering cost included preparation of the system layout and footprint, site drawings and piping
plans, and equipment cut sheets for the permit application (Section 4.3.1). The engineering cost was
$50,659, which was 22% of the total capital investment.
The installation cost included labor and materials to unload and install the treatment system, perform the
piping tie-ins and electrical work, and load and backwash the media (Section 4.3.2). The installation was
performed by Kinetico and its subcontractor, Fann Environmental. The installation cost was $55,106, or
24% of the total capital investment.
The capital cost of $228,309 was normalized to $6,171/gpm ($4.29/gpd) of design capacity using the
system's rated capacity of 37 gpm (or 53,280 gpd). The capital cost also was converted to an annualized
cost of $21,550/yr using a capital recovery factor (CRF) of 0.09439 based on a 7% interest rate and a 20-
yr return period. Assuming that the system operated 24 hr/day, 7 day/wk at the design flowrate of 37 gpm
to produce 19,450,000 gal/yr, the unit capital cost would be $1.11/1,000 gal. During the first six months,
the system operated at approximately 36 gpm, producing 9,350,000 gal of water (Table 4-5), so the unit
capital cost increased slightly to $1.15/1,000 gal.
AWC installed a sun shed structure with a galvanized steel frame, which was later enhanced to
completely enclose the treatment system (Section 4.3.3). The 12 ft x 25 ft structure had a height of 11.5 ft
and was mounted on a 12 ft x 25 ft concrete pad. The structure was pre-engineered to sustain a 90-mph
35
-------
Table 4-15. Capital Investment for Kinetico's Treatment System
Description
Cost
Percent of Capital
Investment Cost
Equipment
Media Skid and Tanks
Air Compressor
Instrumentation and Controls
Backwash Recycle System
Media Eductor Kit
Chemical Injection
Labor
Warranty
Change Order for Flow Totalizer
Equipment Total
$30,134
$2,602
$13,211
$13,486
$943
$11,197
$39,736
$10,610
$625
$122,544
—
—
—
—
—
—
—
—
—
54%
Engineering
Labor
Subcontractor
Engineering Total
$40,021
$10,638
$50,659
—
—
22%
Installation
Labor
Travel
Subcontractor
Installation Total
Total Capital Investment
$15,213
$10,319
$29,574
$55,106
$228,309
—
—
—
24%
100%
wind load and a 30-lb/ft2 snow load. The total cost for the structure was $22,078 which included $4,500
for materials and labor for assembly.
4.6.2 O&M Cost. The O&M cost included media replacement and disposal, chemical supply,
electricity consumption, and labor. Because the system was under warranty, no additional cost was
incurred for repairs. The O&M cost incurred during the first and second media runs are summarized in
Tables 4-16 and 4-17, respectively. Although performed free of charge on October 25, 2004, the media
replacement of both tanks, based on a vendor quote, would have been $8,725, including $4,350 for 44 ft3
of virgin media (or $98.86/ft3) and $4,375 for labor, travel, and spent media sampling, testing, and
disposal. Using this quote and assuming that the cost for labor, travel, and spent media disposal was
proportional to the media quantity, the media replacement cost for one or two tanks with different media
quantities could, therefore, be estimated. By averaging each media replacement cost over the life of the
media, the cost per 1,000 gal of water treated was plotted as a function of the media run length in BVs
and system throughput in gallons, and are shown in Figure 4-11 (for the first media run with 16.7 ft3 of
media in each tank) and Figure 4-12 (for the second media run with 22 ft3 of media in each tank).
For the first media run without pH adjustment, the media replacement cost was estimated to be $3,311 for
one tank or $6,623 for two tanks based on the actual media volume originally loaded in the tanks (i.e.,
16.7 ft3 per tank). Arsenic breakthrough to 10 (ig/L from the lag tank occurred on August 4, 2004, after
treating 2,106,000 gal of water (or about 16,900 BV). If the media in the lead tank was replaced at this
time, the unit replacement cost would have been $1.57/1,000 gal. After the partially exhausted lag tank
was switched to the lead position and followed by the newly replaced tank, the run length for the
subsequent run would be shorter than the initial run (i.e., less than 16,900 BV), thus resulting in an
increased replacement frequency and cost. To reduce the changeout frequency and minimize the
associated scheduling and coordinating effort, it might be more convenient and cost-effective in the long
36
-------
Table 4-16. O&M Cost during First Media Run (06/24/04 - 08/04/04)
Category
Volume Processed (1,000 gal)
Value
2,106
Assumptions
At 10-|ag/L As from lag tank
Media Replacement
No. of Tanks Replaced
Media Volume (ft3)
Media Cost ($)
Labor Cost ($)
Subtotal ($)
Media Replacement Cost ($71,000 gal)
1
16.7
1,651
1,661
3,311
2
33.4
3,302
3,321
6,623
Figure 4-11
Media unit price $98.86/ft3
Prorated from vendor quote of $4,375 for
replacing 44 ft3 of media
Chemical Usage
Chemical Cost ($71,000 gal)
0
No pH adjustment
Electricity Consumption
Incremental Electricity Cost ($/month)
Electricity Cost ($71,000 gal)
244
0.16
Electricity charge $0.12/kWh
Labor
Labor (hr/wk)
Labor Cost ($71,000 gal)
Total O&M Cost ($71,000 gal)
1.9
0.11
Figure 4-11
20-30 min/day
Labor rate = $2 1/hr
Media replacement and $0.27/1,000 gal
for electricity and labor
Table 4-17. O&M Cost during Second Media Run (10/25/04 - 12/22/04)
Category
Volume Processed (1,000 gal)
Value
3,000
Assumptions
Second run continuing
Media Replacement
No. of Tanks Replaced
Media Volume (ft3)
Media Cost ($)
Labor Cost ($)
Subtotal ($)
Media Replacement Cost ($71,000 gal)
1
22
2,175
2,188
4,363
2
44
4,350
4,375
8,725
Figure 4-12
Media unit price $98.86/ft3
Prorated based on $4,375 of labor cost
for replacing 44 ft3 of media
Chemical Usage
Acid Unit Price ($/gal)
Acid Dosage (gal/1,000 gal)
Neutralization and Disposal of 3 Acid
Drums ($)
Acid Cost ($/l,000 gal)
10
16
0.06
180
0.66
50% H2SO4 including shipping
50%H2SO4
Subcontractor quote
Electricity Consumption
Incremental Electricity Cost ($/month)
Electricity Cost ($/l,000 gal)
244
0.
16
Electricity charge $0.12/kWh
Labor
Labor (hr/wk)
Labor Cost ($/l,000 gal)
Total O&M Cost ($/l,000 gal)
1
0.
9
11
Figure 4-12
20-30 min/day
Labor rate = $2 1/hr
Media replacement and $0.93/1,000 gal
for acid, electricity, and labor
37
-------
System Throughput (x1,000 gal)
0 1,250 2,500 3,750 5,000 6,250 7,500 8,750
$1000
"RQ nn
$8.00
$700 -
"55
°> $6.00
o
o
°- $5.00 -
— $4 00 -
«
,9 0 13,
8
200
$10 00
"RQ nn
o
o
IRE; nn °-
"R4 nn "^
in
o
IT nn (i
$2 00
$1 00
$0 00
0
Figure 4-12. Media Replacement and O&M Cost with pH Adjustment
38
-------
run to replace the media in both tanks altogether. In this case, the replacement cost would increase to
$6,623 or $3.15/1,000 gal. Less frequent media changeout could save labor, travel, and administrative
cost.
For the second media run with pH adjustment, the media run length was increased and media replacement
did not occur by the end of this reporting period. The media replacement cost was estimated to be $4,363
for changing out one tank or $8,725 for changing out two tanks (Table 4-18) with each tank loaded with
22 ft3. Based on the vendor-projected media run length of 3,074,000 gal (or 18,680 BV) (Table 4-4), the
unit replacement cost would be $1.42/1,000 gal if only the lead vessel is changed out. Because of the
extended run length, it is less likely to change out both tanks at the same time. Reducing the pH of raw
water incurred $0.66/1,000 gal of acid cost (Table 4-18). In order to offset the added chemical cost, the
run length must be extended to at least 4,772,000 gal (or 29,000 BV) for a lowered unit media
replacement cost of $0.91/1,000 gal, so that the sum of the media replacement and chemical cost is equal
to the media replacement cost of $1.57/1,000 gal without pH adjustment.
The chemical cost was incurred for pH adjustment only. Although NaOCl was used to provide chlorine
residuals in the distribution system, the FA-236-AS system did not change its use rate. The system
consumed approximately 3.4 gpd of 37% H2SO4 from September 17 to October 1, 2004, and then
approximately 3 gpd (or 0.06 gal/1,000 gal) of 50% H2SO4 afterwards. Including the cost of
neutralization and disposal of the empty acid drums, the pH adjustment cost was $0.66/1,000 gal of water
treated. This cost was significantly higher than the vendor-estimated $0.10/1,000 gal of water treated due
to the higher unit price of acid and the neutralization and disposal of the empty acid drums. These costs
will be refined in the final report after more data are available.
Electricity consumption was calculated based on the difference between the average monthly cost from
electric bills before and after the system startup. The difference in cost was approximately $244/month or
$0.16/1,000 gal of water treated.
The routine, non-demonstration related labor activities consumed 20-30 min/day (Section 4.4.6). Based
on this time commitment and a labor rate of $21/hr, the labor cost was $0.11/1,000 gal of water treated.
39
-------
Section 5.0 REFERENCES
ADEQ, see Arizona Department of Environmental Quality.
Arizona Department of Environmental Quality. 2005. Safe Drinking Water: Operator Certification.
Website: http://www.azdeq.gov/environ/water/dw/opcert.html.
Arizona Water Company. 2004. 2003 Annual Water Quality Report for Valley Vista, Arizona PWSID#
13-114.
AWC, see Arizona Water Company.
Battelle. 2003. Revised Quality Assurance Project Plan for Evaluation of Arsenic Removal Technology.
Prepared under Contract No. 68-C-00-185, Task Order No. 0019, for U.S. EPA NRMRL.
November 17.
Battelle. 2004. Final System Performance Evaluation Study Plan: U.S. EPA Demonstration of Arsenic
Removal Technology at Valley Vista, Arizona. Prepared under Contract No. 68-C-00-185, Task
Order No. 0019 for U.S. EPA NRMRL. February 24.
Chen, A.S.C., L. Wang, J. Oxenham, and W. Condit. 2004. Capital Costs of Arsenic Removal
Technologies: U.S. EPA Arsenic Removal Technology Demonstration Program Round 1.
EPA/600/R-04/201. U.S. EPANRML, Cincinnati, OH.
Edwards, M., S. Patel, L. McNeill, H. Chen, M. Frey, A.D. Eaton, R.C. Antweiler, and H.E. Taylor. 1998.
"Considerations in As Analysis and Speciation." J. AWWA (March): 103-113.
EPA, see U.S. Environmental Protection Agency.
Kinetico. 2004. Operation and Maintenance Manual, FA-236-ASAdsorptive Arsenic Removal System.
Rubel, Jr., F. 2003. Design Manual: Removal of Arsenic from Drinking Water by Adsorptive Media.
EPA/600/R-03/019. U.S. EPA NRMRL, Cincinnati, OH.
U.S. Environmental Protection Agency. 2003. Minor Clarification of the National Primary Drinking
Water Regulation for Arsenic. Federal Register, 40 CFR Part 141. March 25.
U.S. Environmental Protection Agency. 2002. Lead and Copper Monitoring and Reporting Guidance
for Public Water Systems. Prepared by EPA's Office of Water. EPA/816/R-02/009. February.
U.S. Environmental Protection Agency. 2001. National Primary Drinking Water Regulations: Arsenic
and Clarifications to Compliance and New Source Contaminants Monitoring. Federal Register,
66:14:6975. January 22.
Wang, L., W. Condit, and A. Chen. 2004. Technology Selection and System Design: U.S. EPA Arsenic
Removal Technology Demonstration Program Round 1. EPA/600/R-05/001. U.S. EPA
NRMRL, Cincinnati, OH.
Westerhoff, P.K., T.M. Benn, L. Wang, and A.S.C. Chen. 2006. Assessing Arsenic Removal by Metal
(Hydr)Oxide Adsorbents Using Rapid Small Scale Column Tests. Draft in Progress. U.S. EPA
NRMRL, Cincinnati, OH.
40
-------
APPENDIX A
OPERATIONAL DATA
-------
US EPA Arsenic Demonstration Project at Valley Vista, AZ - Daily System Operation Log Sheet
Daily System Operation
Week
No.
1
2
3
4
5
6
7
8
9
10
Date & Time
6/24/0415:05
6/25/04 12:00
6/28/04 10:30
6/29/04 12:05
6/30/04 13:05
7/1/0412:20
7/2/0413:55
7/6/0414:30
7/7/0412:55
7/8/0413:40
7/9/0412:00
7/12/04 10:15
7/1 3/04 1 1 :35
7/14/04 10:40
7/15/04 13:40
7/16/0411:40
7/19/04 11:15
7/20/04 12:55
7/21/049:45
7/22/04 14:20
7/23/04 14:00
7/26/04 1 1 :30
7/27/04 1 1 :00
7/28/04 9:30
7/29/04 13:30
7/30/04 12:30
8/2/04 1 1 :00
8/3/0410:40
8/4/04 9:20
8/5/0413:30
8/6/0415:05
8/9/0413:25
8/10/0416:55
8/11/0411:32
8/12/0413:40
8/13/04 13:50
8/16/0412:15
8/17/0414:07
8/18/049:45
8/19/0411:40
8/20/04 12:00
8/23/04 1 1 :38
8/24/04 1 1 :55
8/25/04 9:30
8/26/04 1 1 :40
8/27/04 14:10
POEWell#2
Run
Time
hr
NA
16.0
50.3
17.1
16.2
15.8
18.4
65.7
14.7
15.8
13.9
45.6
16.3
14.9
17.2
14.0
44.8
16.0
13.1
18.2
14.9
43.7
14.8
14.3
17.7
14.6
44.2
14.9
14.1
17.6
16.0
44.6
17.7
11.8
16.9
15.4
44.6
17.4
12.8
16.8
16.1
47.4
15.6
13.7
16.6
17.3
Master
Totalizer1"1
gal
15273800
15325100
15497800
15560600
15621700
15678700
15741300
15977300
16032900
16093500
16148100
16320000
16382000
16438400
16504200
16558200
16733600
16794700
16846300
16916800
16974700
17145600
17203300
17258800
17327400
17383900
17556400
17614800
17670000
17739400
17802200
17974600
18041900
18087500
18151500
18210800
18380200
18444000
18492300
18556000
18616200
18792300
18851900
18904900
18969100
19034400
Lead/
Lag
Tank
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
Treatment System
Flowrate
gpm
35
36
36
36
35
36
36
39
35
36
35
36
36
36
36
36
36
38
36
35
35
36
36
36
36
36
36
36
36
36
36
35
36
36
36
36
36
37
36
36
36
36
36
36
36
36
Totalizer
gal
24472
69934
221594
276814
330598
380830
436016
644385
689640
742924
791020
942199
996735
46440
104290
151771
306110
360500
405873
467800
518736
669000
719830
768642
828940
878699
30800
81830
130350
191400
246755
398500
457690
497895
554220
606420
756500
812550
855100
911150
964100
119280
171800
218540
275060
332625
Cumulative
Throughput
gal
NA
45462
197122
252342
306126
356358
411544
619913
665168
718452
766548
917727
972263
1021968
1079818
1127299
1281638
1336028
1381401
1443328
1494264
1644528
1695358
1744170
1804468
1854227
2006328
2057358
2105878
2166928
2222283
2374028
2433218
2473423
2529748
2581948
2732028
2788078
2830628
2886678
2939628
3094808
3147328
3194068
3250588
3308153
Avg
Flowrate
gpm
NA
36.2
35.9
36.0
35.9
36.0
36.0
36.5
33.6
35.9
35.9
35.9
35.9
35.9
35.7
36.0
35.9
35.3
36.3
36.1
35.9
36.0
36.0
36.2
35.9
36.1
36.0
35.9
35.7
36.1
36.1
36.0
35.9
36.0
35.9
36.0
35.5
36.1
36.1
36.0
36.3
36.1
36.0
36.1
36.0
36.2
Bed
Volume
BV
NA
364
1578
2020
2451
2853
3295
4963
5325
5751
6137
7347
7783
8181
8644
9024
10260
10695
11059
11554
11962
13165
13572
13963
14445
14844
16061
16470
16858
17347
17790
19005
19479
19801
20252
20669
21871
22320
22660
23109
23533
24775
25196
25570
26022
26483
Pressure
Inlet
psig
73
74
74
74
74
74
74
76
74
74
74
74
74
74
74
74
74
76
74
74
74
74
74
74
74
74
74
74
74
74
76
75
75
75
75
75
74
76
74
76
74
74
75
74
74
75
Between
Tanks
psig
70
70
70
70
70
70
70
72
70
70
70
70
70
70
70
70
70
72
70
70
70
70
70
71
70
70
71
71
71
72
72
71
71
71
71
71
71
72
71
72
71
71
72
71
71
71
Outlet
psig
68
68
68
68
68
68
68
70
68
68
68
68
68
69
69
69
69
71
69
69
69
69
69
70
69
69
69
69
69
70
71
70
70
70
70
70
70
71
70
71
70
70
71
70
70
70
iP
Inlet -
Between
psi
3
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
3
4
4
3
3
3
2
4
4
4
4
4
4
3
4
3
4
3
3
3
3
3
4
Between -
Outlet
psi
2
2
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
In-line
pH
S.U.
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
7.9
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.1
Backwash Water Recycle
Bag Filter
Inlet
Pressure
psig
77
78
78
78
78
78
77
99
78
78
78
77
78
79
78
78
79
106
79
79
78
78
78
79
78
79
78
78
78
79
79
79
79
79
79
79
79
109
79
79
79
79
80
79
79
79
Bag Filter
Outlet
Pressure
psig
77
78
78
78
78
77
77
100
78
78
78
77
78
79
78
78
79
106
79
79
78
78
78
79
78
79
78
78
77
78
78
78
78
78
78
78
78
109
78
79
78
78
79
78
78
79
Recycle
Flow
gpm
NA
NA
NA
NA
NA
NA
NA
2
NA
NA
NA
NA
NA
NA
NA
NA
NA
3
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2
NA
NA
NA
NA
NA
NA
NA
NA
Acid
Tank
Level
gal
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
-------
US EPA Arsenic Demonstration Project at Valley Vista, AZ - Daily System Operation Log Sheet
Daily System Operation
Week
No.
11
12
13
14
15
16
17
18
19
20
Date & Time
8/30/0414:15
8/31/0410:15
9/1/04 10:07
9/2/04 1 1 :30
9/3/04 1 1 :30
9/7/04 1 1 :00
9/8/0410:17
9/9/0413:50
9/10/0414:05
9/13/049:40
9/14/0414:05
9/15/0410:00
9/16/0417:40
9/17/0412:20
9/18/0411:00
9/20/0413:35
9/21/0411:55
9/22/04 9:05
9/23/0413:26
9/24/0413:20
9/27/0413:45
9/28/0413:20
9/29/04 9:50
9/30/0414:15
10/1/0413:50
10/4/0414:00
10/5/0410:45
10/6/049:45
10/7/0413:30
10/8/04 17:45
10/12/0413:00
10/13/049:45
10/14/0414:15
10/15/0414:30
10/18/0410:50
10/19/0410:00
10/20/0411:50
10/21/0412:25
10/22/0414:55
10/25/0415:00
10/26/0413:30
10/27/0411:40
10/28/0410:50
10/29/0412:40
11/1/0410:00
11/2/049:45
11/3/049:50
11/4/0414:40
11/5/0413:50
POE Well #2
Run
Time
hr
47.6
13.3
15.4
17.2
16.4
64.3
15.5
18.5
15.6
45.1
18.2
12.8
20.8
12.0
NA
47.0
14.6
14.0
18.8
16.0
46.0
14.4
12.5
17.3
14.4
46.4
13.1
14.7
17.5
18.3
58.3
13.1
18.5
15.4
43.5
14.9
16.6
15.7
16.5
41.2
11.1
14.4
14.6
16.3
42.5
15.0
15.0
NA
22.9
Master
Totalizer'"1
gal
19211000
19259900
19316700
19378400
19437200
19671000
19728000
19795400
19854600
20019400
20086000
20135100
20212800
20258400
NA
20436300
20491100
20542800
20610600
20699300
20846800
20902100
20952400
21022100
21077900
21254200
21305600
21361900
21429800
21499100
21719900
21768200
21838500
21893000
22060700
22118200
22181700
22241900
22306500
22467500
22507400
22561600
22618500
22682400
22849900
22910200
22969400
23039700
23096000
Lead/
Lag
Tank
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
Treatment System
Flowrate
gpm
35
36
36
36
36
36
35
35
36
36
37
36
36
36
NA
36
36
36
36
36
35
36
36
36
36
36
36
36
36
36
36
36
35
36
36
36
37
36
36
NA
36
36
36
36
36
36
36
36
36
Totalizer
gal
488060
531285
581385
635700
687530
893650
943885
3356
55564
200890
260530
303780
372350
412570
NA
569930
618230
663870
724980
776630
933095
983890
28230
89593
140530
296207
341307
391229
451156
512237
707526
751266
813345
866000
14290
65148
121356
174490
232293
374531
411103
448897
508900
565237
713453
766478
818612
880599
930338
Cumulative
Throughput
gal
3463588
3506813
3556913
3611228
3663058
3869178
3919413
3978884
4031092
4176418
4236058
4279308
4347878
4388098
NA
4545458
4593758
4639398
4700508
4752158
4908623
4959418
5003758
5065121
5116058
5271735
5316835
5366757
5426684
5487765
5683054
5726794
5788873
5841528
5989818
6040676
6096884
6150018
6207821
0
36572
74366
134369
190706
338922
391947
444081
506068
555807
Avg
Flowrate
gpm
35.9
36.0
35.0
35.7
36.0
36.0
36.0
36.0
35.9
35.8
35.0
36.2
36.1
35.9
NA
35.8
36.0
35.9
35.9
36.0
36.0
35.9
36.0
36.0
36.0
36.0
36.2
36.2
36.0
36.0
35.7
35.1
36.3
36.2
36.2
36.6
36.3
36.0
36.4
NA
27.1
28.4
43.2
36.3
35.6
37.2
36.1
35.8
35.8
Bed
Volume
BV
27727
28073
28474
28909
29324
30974
31376
31852
32270
33434
33911
34257
34806
35128
NA
36388
36775
37140
37629
38043
39295
39702
40057
40548
40956
42202
42563
42963
43443
43932
45495
45845
46342
46764
47951
48358
48808
49233
49696
0
222
452
817
1159
2060
2382
2699
3075
3378
Pressure
Inlet
psig
75
75
74
74
74
74
74
74
75
75
75
74
74
74
NA
76
76
75
75
75
75
75
74
75
75
75
75
75
75
75
75
75
75
75
75
75
76
75
76
NA
76
76
76
76
76
76
76
76
76
Between
Tanks
psig
71
71
71
71
71
71
71
71
71
71
71
71
71
71
NA
72
72
72
71
72
71
72
71
72
72
72
72
72
72
72
72
72
72
72
72
72
73
72
73
NA
73
73
73
73
73
73
73
73
73
Outlet
psig
70
70
70
70
70
70
70
70
70
70
70
70
70
70
NA
71
71
71
70
71
70
70
70
71
71
71
71
70
71
71
71
71
71
71
71
71
72
71
72
NA
71
72
72
72
72
72
72
72
72
iP
Inlet -
Between
psi
4
4
3
3
3
3
3
3
4
4
4
3
3
3
NA
4
4
3
4
3
4
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
NA
3
3
3
3
3
3
3
3
3
Between -
Outlet
psi
1
1
1
1
1
1
1
1
1
1
1
1
1
1
NA
1
1
1
1
1
1
2
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
NA
2
1
1
1
1
1
1
1
1
In-line
pH
S.U.
8.0
8.0
7.3*
7.8
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
7.9
NA
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.1
7.2
7.9
7.9
7.9
7.9
7.2
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.2
7.1
Backwash Water Recycle
Bag Filter
Inlet
Pressure
psig
79
79
78
79
79
79
79
79
79
79
110
78
78
79
NA
81
80
80
80
79
79
79
79
80
80
80
80
79
79
79
79
79
80
80
80
80
109
80
80
NA
81
81
81
81
82
82
82
81
81
Bag Filter
Outlet
Pressure
psig
79
79
77
78
78
78
78
78
78
78
110
78
78
78
NA
80
79
78
79
79
79
79
78
79
79
79
79
78
78
78
78
78
79
79
79
79
108
79
79
NA
80
80
80
79
81
79
79
79
79
Recycle
Flow
gpm
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
4.6
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Acid
Tank
Level
gal
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
55
NA
NA
NA
NA
34
NA
22
NA
NA
NA
8
54
52
50
NA
NA
32
32
NA
NA
NA
30
28
26
22
NA
10
63
61
58
51
48
45
41
39
-------
US EPA Arsenic Demonstration Project at Valley Vista, AZ - Daily System Operation Log Sheet
Daily System Operation
Week
No.
21
22
23
24
25
26
27
Date & Time
11/8/0413:00
11/9/049:30
11/10/049:15
11/12/04 11:40
11/15/04 10:50
11/16/04 11:25
11/17/04 11:00
11/18/04 13:45
11/19/04 11:00
11/22/04 11:25
11/23/04 11:00
11/24/0411:15
11/29/04 12:45
11/30/04 12:00
12/1/0410:15
12/2/0411:00
12/3/0411:30
12/6/0410:00
12/7/0413:40
12/8/0410:00
12/9/0414:00
12/10/0413:00
12/13/049:50
12/14/0411:25
12/15/04 13:18
1 2/1 6/04 1 1 :40
12/17/0415:45
12/20/04 12:10
12/21/04 12:25
12/22/0413:50
POEWell#2
Run
Time
hr
71.3
20.5
23.8
50.5
71.2
24.5
23.5
26.9
21.2
70.9
23.4
23.5
121.5
23.3
22.2
24.8
24.6
70.2
27.8
20.3
28.3
22.8
68.8
25.5
26.0
22.3
28.2
68.3
23.3
25.4
Master
Totalizer1"1
gal
23270400
23320500
23378900
23502900
23677800
23738100
23796100
23862200
23914400
24082600
24140300
24197900
24498500
24555700
24610700
24671700
24732500
24905700
24974400
25024600
25094500
25151100
25321000
25384100
25448300
25503500
25573300
25742100
25799900
25862800
Lead/
Lag
Tank
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
A/B
Treatment System
Flowrate
gpm
36
36
36
36
36
36
36
36
36
36
36
37
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
36
Totalizer
gal
83922
128264
179798
289145
443389
496782
547738
606003
652019
805679
856977
907501
172782
223259
271789
325565
379341
531705
592582
636518
698174
748362
NA
953024
9579
58162
119385
268249
319082
374418
Cumulative
Throughput
gal
709391
753733
805267
914614
1068858
1122251
1173207
1231472
1277488
1431148
1482446
1532970
1798251
1848728
1897258
1951034
2004810
2157174
2218051
2261987
2323643
2373831
NA
2578493
2635048
2683631
2744854
2893718
2944551
2999887
Avg
Flowrate
gpm
36.0
36.1
36.2
36.1
36.1
36.2
36.0
36.3
36.1
35.4
36.3
34.7
36.4
36.2
36.4
36.2
36.6
36.0
36.7
36.0
36.7
36.4
NA
NA
36.4
36.2
36.3
36.3
34.9
36.3
Bed
Volume
BV
4311
4580
4893
5558
6495
6820
7129
7483
7763
8697
9009
9316
10928
11234
11529
11856
12183
13109
13479
13746
14120
14425
NA
15669
16013
16308
16680
17585
17893
18230
Pressure
Inlet
psig
77
76
76
76
76
76
76
76
76
76
76
77
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
Between
Tanks
psig
74
73
73
73
73
73
73
72
73
72
72
74
73
73
73
73
73
73
73
73
73
73
72
72
72
72
72
72
72
72
Outlet
psig
73
72
72
71
72
72
72
71
71
71
71
72
71
71
71
71
71
71
71
71
71
71
71
71
71
71
71
71
71
71
iP
Inlet -
Between
psi
3
3
3
3
3
3
3
4
3
4
4
3
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
Between -
Outlet
psi
1
1
1
2
1
1
1
1
2
1
1
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
1
1
1
1
In-line
pH
S.U.
7.1
7.1
7.2
7.2
7.1
7.1
7.1
7.2
7.1
7.1
7.1
7.1
7.1
7.2
7.1
7.1
7.2
7.1
7.2
7.2
7.1
7.1
7.2
7.2
7.2
7.2
7.2
7.2
7.1
7.2
Backwash Water Recycle
Bag Filter
Inlet
Pressure
psig
81
81
81
81
81
81
81
81
81
80
81
83
101
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
78
80
82
82
82
Bag Filter
Outlet
Pressure
psig
80
80
79
79
79
79
79
79
79
79
79
80
79
0
0
0
0
0
0
0
0
0
0
0
0
80
79
79
79
79
Recycle
Flow
gpm
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
2
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
Acid
Tank
Level
gal
30
27
24
19
10
63
60
NA
53
42
40
38
25
22
20
18
14
59
55
52
48
44
33
29
24
20
16
4
56
52
(a) Throughput based on the Master Totalizer is 12% higher than that based on Treatment System Totalizer due to inherent accuracy errors.
(b) BV calculation based on 16.7 ftVtank until 10/24/04. BV calculation since 10/26/04 based on 22 ffVtank.
Highlighted rows indicate backwash; NA = data not available.
-------
APPENDIX B
ANALYTICAL DATA TABLES
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/L(a)
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(a)
Hg/L
|xg/L
Hg/L
|xg/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
06/30/04
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/L(a)
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(a)
Hg/L
|xg/L
Hg/L
|xg/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
07/28/04
IN
-
167
0.1
8.1
0.8
<0.1
18.2
0.2
7.8
20.8
6.5
196
-
-
177.6
98.1
79.5
39.0
39.8
<0.1
0.5
39.3
<25
<25
0.1
0.1
<10
<10
AC(C)
-
-
-
-
-
-
-
-
7.7
20.6
6.5
571
0.6
0.6
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
13,963
167
0.1
8.1
0.8
<0.1
17.4
0.2
7.7
20.3
6.0
612
0.6
0.7
178.2
100.6
77.6
24.2
24.4
<0.1
0.4
24.0
<25
<25
<0.1
<0.1
<10
<10
167
0.1
8.1
0.8
<0.1
17.1
0.3
7.7
20.3
5.8
621
0.6
0.7
179.5
101.1
78.4
5.4
5.7
<0.1
0.4
5.3
<25
<25
<0.1
<0.1
<10
<10
08/04/04
IN
-
168
-
-
-
<0.1
19.0
0.2
7.6
20.8
6.0
186
-
-
-
-
-
46.2
-
-
-
-
<25
-
0.2
-
-
-
AC
-
-
-
-
-
-
-
-
7.9
21.1
6.5
560
0.8
0.9
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
16,858
164
-
-
-
<0.1
18.4
0.3
7.7
20.5
6.0
608
0.4
0.4
-
-
-
31.2
-
-
-
-
<25
-
<0.1
-
-
-
160
-
-
-
<0.1
17.9
0.2
7.7
20.6
6.4
633
0.4
0.4
-
-
-
10.7
-
-
-
-
<25
-
0.1
-
-
-
08/11/04
IN
-
160
-
-
-
<0.1
18.7
0.3
8.3
21.0
6.1
196
-
-
-
-
-
37.5
-
-
-
-
<25
-
0.4
-
<10
-
AC
-
-
-
-
-
-
-
-
7.9
20.8
5.8
570
0.4
0.4
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
19,801
156
-
-
-
<0.1
18.2
0.2
7.9
20.5
5.7
605
0.4
0.4
-
-
-
27.8
-
-
-
-
<25
-
<0.1
-
<10
-
151
-
-
-
<0.1
17.8
0.1
7.8
20.6
6.1
606
0.4
0.4
-
-
-
12.7
-
-
-
-
<25
-
0.4
-
<10
-
08/18/04
IN
-
152
-
-
-
<0.1
19.3
0.3
7.7
20.5
6.0
179
-
-
-
-
-
34.8
-
-
-
-
<25
-
0.4
-
<10
-
AC
-
-
-
-
-
-
-
-
7.7
20.2
5.9
586
0.4
0.5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
22,660
156
-
-
-
<0.1
18.9
0.2
7.7
20.4
5.3
622
0.5
0.5
-
-
-
29.4
-
-
-
-
28.3
-
0.4
-
29.1
-
156
-
-
-
<0.1
18.8
0.4
7.7
20.3
6.0
635
0.5
0.5
-
-
-
15.4
-
-
-
-
<25
-
0.2
-
11.1
-
(a) As CaCO3. (b) As PO4. (c) Switched from post-chlorination to prechlorination on 07/27/04.
IN = at inlet; TA = after Tank A; TB = after Tank B; AC = after prechlorination (field parameters only).
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/Lw
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L«
mg/L«
mg/L«
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
08/25/04
IN
-
160
0.1
8.3
0.8
<0.1
19.5
0.1
7.7
20.7
6.4
187
-
-
135.8
66.2
69.6
47.6
47.3
0.3
0.6
46.7
<25
<25
0.4
0.3
-
-
AC
-
-
-
-
-
-
-
-
7.7
20.3
5.8
572
0.4
0.4
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
25,570
156
0.1
8.3
0.8
<0.1
19.0
<0.1
7.7
20.3
6.1
603
0.4
0.5
140.0
69.6
70.4
35.3
34.9
0.4
1.0
33.9
<25
<25
0.7
0.3
-
-
156
0.1
8.3
0.8
<0.1
18.9
<0.1
7.7
20.3
5.9
604
0.4
0.5
136.0
68.3
67.7
25.4
24.7
0.7
1.3
23.4
<25
<25
1.0
0.6
-
-
09/01/04
IN
-
157
-
-
-
<0.1
18.9
0.2
7.8
20.6
6.2
194
-
-
-
-
-
44.6
-
-
-
-
<25
-
0.2
-
<10
-
AC
-
-
-
-
-
-
-
-
7.8
20.3
5.5
594
0.5
0.5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
28,474
161
-
-
-
<0.1
18.5
0.4
7.7
20.3
6.1
609
0.5
0.5
-
-
-
37.8
-
-
-
-
<25
-
<0.1
-
<10
-
157
-
-
-
<0.1
18.4
0.4
7.7
20.2
5.8
618
0.5
0.5
-
-
-
26.5
-
-
-
-
<25
-
<0.1
-
<10
-
09/08/04
IN
-
153
-
-
-
<0.1
18.7
0.3
7.7
20.7
6.2
207
-
-
-
-
-
46.7
-
-
-
-
<25
-
0.2
-
<10
-
AC
-
-
-
-
-
-
-
-
7.7
20.3
5.9
572
0.5
0.5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
31,376
157
-
-
-
<0.1
18.4
0.4
7.7
20.2
5.5
605
0.4
0.5
-
-
-
40.7
-
-
-
-
<25
-
<0.1
-
<10
-
161
-
-
-
<0.1
18.5
0.2
7.8
20.3
5.8
604
0.4
0.5
-
-
-
28.2
-
-
-
-
<25
-
<0.1
-
<10
-
09/15/04
IN
-
158
162
-
-
-
<0.06
<0.06
19.0
18.9
0.4
0.2
7.7
20.4
6.0
201
-
-
-
-
-
36.6
37.5
-
-
-
-
<25
<25
-
0.4
0.4
-
<10
<10
-
AC
-
-
-
-
-
-
-
-
7.7
20.3
5.9
585
0.4
0.4
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
34,257
162
162
-
-
-
<0.06
<0.06
18.5
18.8
0.5
0.5
7.7
20.3
5.8
605
0.4
-
-
-
-
33.5
34.0
-
-
-
-
<25
<25
-
0.2
0.5
-
<10
<10
-
162
162
-
-
-
<0.06
<0.06
18.5
18.6
0.7
0.7
7.7
20.3
6.0
612
0.4
0.4
-
-
-
26.0
25.6
-
-
-
-
<25
<25
-
0.2
0.1
-
10.7
10.2
-
(a) As CaCO3. (b) As PO4.
IN = at inlet; TA = after Tank A; TB = after Tank B; AC = after prechlorination (field parameters only).
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/L(a)
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(a)
Hg/L
|xg/L
Hg/L
|xg/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
09/22/04
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/L(a)
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(a)
Hg/L
|xg/L
Hg/L
|xg/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
10/27/04
-------
Analytical Results from Long-Term Sampling, Valley Vista, AZ
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
Sulfate
Nitrate (as N)
Orthophosphate
Silica (as SiO2)
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (soluble)
As (particulate)
As (III)
As(V)
Fe (total)
Fe (soluble)
Mn (total)
Mn (soluble)
Al (total)
Al (soluble)
-
mg/Lw
mg/L
mg/L
mg/L
mg/L*'
mg/L
NTU
-
°C
mg/L
mV
mg/L
mg/L
mg/L«
mg/L«
mg/Lw
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
re/L
12/01/04
IN
-
160
156
-
-
-
<0.06
<0.06
18.4
18.7
0.2
0.1
8.4
18.5
5.7
227
-
-
-
-
-
36.5
36.5
-
-
-
-
<25
<25
-
0.2
0.2
-
<10
<10
-
AC
-
-
-
-
-
-
-
-
6.9
19.1
5.1
746
0.5
0.5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
11,529
120
128
-
-
-
<0.06
<0.06
18.0
18.0
0.2
0.2
6.9
18.5
5.6
691
0.5
0.5
-
-
-
3.1
3.1
-
-
-
-
<25
<25
-
<0.1
<0.1
-
<10
<10
-
124
124
-
-
-
<0.06
<0.06
17.2
17.0
0.1
0.2
6.9
18.8
5.2
712
0.5
0.5
-
-
-
0.3
0.2
-
-
-
-
<25
<25
-
0.1
0.1
-
<10
<10
-
12/08/04
IN
-
154
-
-
-
<0.06
19.0
0.2
7.7
18.1
5.5
248
-
-
-
-
-
37.3
-
-
-
-
<25
-
0.3
-
<10
-
AC
-
-
-
-
-
-
-
-
6.7
19.0
6.0
710
0.4
0.5
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
13,746
122
-
-
-
<0.06
18.7
0.4
6.7
19.0
5.6
727
0.4
0.5
-
-
-
4.0
-
-
-
-
<25
-
<0.1
-
<10
-
122
-
-
-
<0.06
18.6
0.3
6.7
19.0
5.5
744
0.4
0.5
-
-
-
0.3
-
-
-
-
<25
-
<0.1
-
<10
-
12/15/04
IN
-
155
<0.1
8.1
0.8
<0.06
19.5
0.1
7.8
19.6
5.3
235
-
-
181.4
104.9
76.5
39.2
40.4
<0.1
0.4
40.0
<25
<25
0.2
0.1
<10
<10
AC
-
-
-
-
-
-
-
-
6.8
20.4
5.9
754
0.4
0.4
-
-
-
-
-
-
-
-
-
-
-
-
-
-
TA
TB
16,013
114
<0.1
50
0.7
<0.06
18.3
0.2
6.7
20.4
5.5
111
0.4
0.4
167.2
95.9
71.3
4.3
4.3
<0.1
0.4
3.9
<25
<25
0.1
<0.1
<10
<10
114
<0.1
45
<0.04
------- |