EPA/600/R-06/031
April 2006
Arsenic Removal from Drinking Water by Adsorptive Media
U.S. EPA Demonstration Project at Bow, NH
Six-Month Evaluation Report
by
Jeffrey L. Oxenham
Abraham S.C. Chen
Lili Wang
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
-------
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.
-------
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 groundwater; 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
-------
ABSTRACT
This report documents the activities performed during and the results obtained from the first six months
of the arsenic removal treatment technology demonstration project at the White Rock Water Company
(WRWC) public water system, a small residential drinking water facility in Bow, NH. The objectives of
the project are to evaluate the effectiveness of the ADI Group, Inc. (ADI) G2 media in removing arsenic
to meet the new arsenic maximum contaminant level (MCL) of 10 |o,g/L, the reliability of the treatment
system, the required system operation and maintenance (O&M) and operator's skills, and the capital and
O&M costs of the technology. The project also characterizes the water in the distribution system and
process residuals produced by the treatment system.
The arsenic adsorption system consisted of two vertical, 72-inch-diameter and 72-inch-sidewall-height
stainless steel vessels configured in series. The adsorption vessels were originally designed to operate in
parallel for the Holiday Acres Mobile Home Park in Allenstown, NH with a flowrate of 70 gallons per
minute (gpm) (35 gpm per vessel). Due to the switch to the site in Bow with a total flowrate of about 40
gpm, the flowrate was reduced by 43%; therefore, the system was reconfigured to operate in series. At 40
gpm, each vessel provided an empty bed contact time (EBCT) of 16 min (or 32 min total contact time)
and a hydraulic loading rate of 1.4-gpm/ft2. The 16-min EBCT was 60% longer than that normally
recommended by the vendor and the 1.4-gpm/ft2 hydraulic loading rate was about 50% lower than that
normally applied to the G2 media.
The G2 media is a granular, calcined diatomite substrate coated with ferric hydroxide. Because of its
inherently high pH values from the manufacturing process, the G2 media was conditioned on-site with
sulfuric acid before the system was put into service. To increase the media adsorption capacity, the raw
water was adjusted to a target value of 6.8, and later 6.4, using a 93% sulfuric acid solution. The treated
water was adjusted for pH again to a target value of 7.5 using a 25% caustic solution before entering the
distribution system. In-line pH probes were used to monitor the pH values of the feed water and treated
water but the rates of acid and caustic addition were controlled via manual adjustments to the pump stroke
length. The relative feed rates were then flow-paced with a water meter located on the discharge line
following the treatment system.
The arsenic adsorption system became operational on October 13, 2004. Through April 24, 2005, the
system operated for 1,741 hr, treating approximately 3,858,000 gal of water or 6,067 bed volumes (BVs).
Total As concentrations in the raw water averaged 49.3 |og/L, present almost entirely as As(V). After the
lead vessel, greater than 30 |o,g/L of total As was unexpectedly detected in samples collected just after
startup on October 13 and about one week later on October 19, 2004. After about 380 BVs of throughput,
total As concentrations decreased to 12.6 to 15.6 |o,g/L before beginning a steady increase to 26.3 |o,g/L at
about 2,600 BVs by April 12, 2005. Total As concentrations after the lag vessel also were high during
the first two weeks of system operation, with 16.7 to 21.8 |o,g/L of arsenic measured on October 13 and
October 19, 2004, respectively. Afterwards, the concentrations dropped to 1.7 |o,g/L after about 2,500
BVs and then increased steadily to 5.8 |o,g/L after about 5,700 BVs by April 12, 2005. ADI attributed the
elevated arsenic concentrations just after the system startup to the leaching of arsenic from the G2 media
prepared with FeCl3 containing arsenic and manganese as impurities. While this might explain the
elevated arsenic levels observed in the treated water during the first two weeks of system operation, it
does not explain why the arsenic concentrations remained high (i.e., 12.6 |o,g/L or greater) following the
lead vessel throughout the first six months of operation.
Increases in both manganese and silica were observed in the treated water following the adsorption
vessels, indicating leaching of these constituents from the media. After about 3,000 BVs, manganese
concentrations decreased to levels similar to those in the raw water. The leaching of silica from both
IV
-------
vessels leveled off after about 2,000 BVs, but continued throughout the remainder of the study period
with an increase in concentrations ranging from 1.6 to 6.2 mg/L.
The system was backwashed only twice during this period because of low pressure losses (i.e., 1-2
pounds per square inch [psi]) across the adsorption vessels. Analysis of the backwash water indicated
that soluble As concentrations were either similar to or lower than the levels measured in the source
water. Since finished water was used for backwash, some arsenic might have been desorbed from the
media during backwashing. Future backwash samples will include collection and analysis of total
suspended solids (TSS) and total As, Fe, and Mn.
Comparison of the distribution system sampling results before and after the installation of the ADI G2
media system showed a decrease in arsenic concentration (from 36.9 - 52.3 |o,g/L to 3.9 - 12.4 |o,g/L) at all
three EPA Lead and Copper Rule (LCR) sampling locations. Manganese concentrations increased to as
high as 16.0 |o,g/L in the distribution system during the first three months of system operation, apparently
due to leaching of manganese from the G2 media, as mentioned above. Following a drop in pH of the
treated water in December 2004, the lead concentration in the January 12, 2005 sample increased to 9.9
|o,g/L at one sampling location and copper levels increased across all three sampling locations, with the
most noticeable increase exceeding the action level of 1.3 mg/L at one location. During the subsequent
monthly sampling events, the pH values were better controlled; however, the lead and copper levels
continued to be higher than those observed before the pH drop in January.
The most significant operational issue observed was related to the addition of acid and caustic necessary
to maintain the desired pH ranges of the feed water to the treatment system and the finish water to the
storage tank and distribution system. Confounding the proper addition of acid and caustic were
continuing discrepancies observed in pH readings from the inline pH probes versus a WTW field meter
used to measure pH at sampling locations across the treatment train. In fact, an inadvertent lowering of
the caustic addition in late December resulted in the pH drop observed in the distribution system samples
collected on January 12, 2005, and the corresponding increase in lead and copper levels in the distribution
system as described above.
The capital investment cost of $154,700 includes $102,600 for equipment, $12,500 for site engineering,
and $39,600 for installation. Using the system's actual capacity of 40 gpm (57,600 gal per day [gpd]), the
capital cost was $3,868/gpm ($2.68/gpd) and equipment-only cost was $2,565/gpm ($1.78/gpd). These
calculations did not include the cost of the building construction.
O&M costs included only incremental costs associated with the adsorption system, such as media
replacement and disposal, chemical supply, electricity, and labor. Incremental costs for electricity were
negligible. Although media replacement and disposal did not take place during the first six months of
operation, the cost to change out the lead vessel was estimated to be $9,396 based on information
provided by the vendor and a local subcontractor. This cost was used to estimate the media replacement
cost per 1,000 gal of water treated as a function of the projected media run length to the 10-|o,g/L arsenic
breakthrough.
-------
CONTENTS
DISCLAIMER ii
FOREWORD iii
ABSTRACT iv
APPENDICES vii
FIGURES vii
TABLES vii
ABBREVIATIONS AND ACRONYMS viii
ACKNOWLEDGMENTS x
1.0 INTRODUCTION 1
1.1 Background 1
1.2 Treatment Technologies for Arsenic Removal 1
1.3 Project Objectives 2
2.0 CONCLUSIONS 3
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 6
3.3.1 Source Water Sample Collection 8
3.3.2 Treatment Plant Water Sample Collection 8
3.3.3 Backwash Water Sample Collection 8
3.3.4 Backwash Solid Sample Collection 8
3.3.5 Distribution System Water Sample Collection 8
3.4 Sampling Logistics 8
3.4.1 Preparation of Arsenic Speciation Kits 9
3.4.2 Preparation of Sampling Coolers 9
3.4.3 Sample Shipping and Handling 9
3.5 Analytical Procedures 9
4.0 RESULTS AND DISCUSSION 11
4.1 Facility Description 11
4.1.1 Source Water Quality 11
4.1.2 Pre-Demonstration Treated Water Quality 14
4.1.3 Distribution System 14
4.2 Treatment Process Description 14
4.3 System Installation 20
4.3.1 Permitting 20
4.3.2 Building Construction 20
4.3.3 Installation, Shakedown, and Startup 21
4.4 System Operation 21
4.4.1 Operational Parameters 21
4.4.2 Backwash 22
4.4.3 Residuals Management 22
4.4.4 System Operation Reliability and Simplicity 22
4.5 System Performance 24
4.5.1 Treatment Plant Sampling 24
4.5.2 Backwash Water Sampling 33
VI
-------
4.5.3 Distribution System Water Sampling 33
4.6 System Costs 34
4.6.1 Capital Costs 34
4.6.2 Operation and Maintenance Costs 36
5.0 REFERENCES 39
APPENDICES
APPENDIX A: Operational Data A-l
APPENDIX B: Analytical Results B-l
FIGURES
Figure 4-1. Existing Underground Treatment and Control Structure 11
Figure 4-2. Existing Storage Tanks in Underground Concrete Structure 12
Figure 4-3. Existing Activated Alumina System in the Underground Treatment and Control
Structure 12
Figure 4-4. Schematic of G2 Media Adsorption System (Provided by ADI) 16
Figure 4-5. Process Flow Diagram and Sampling Locations 18
Figure 4-6. ADI G2 Media Arsenic Adsorption System 19
Figure 4-7. New Treatment Building Addition 20
Figure 4-8. Concentration of Arsenic Species at the IN, AP, TA, and TB Sampling Locations 28
Figure 4-9. Total Arsenic Breakthrough Curves 29
Figure 4-10. Total Manganese Concentrations Over Time 30
Figure 4-12. Silica Concentrations Over Time 32
Figure 4-13. Media Replacement and O&M Costs 38
TABLES
Table 1-1. Summary of Arsenic Removal Demonstration Technologies and Source Water
Quality Parameters 2
Table 3-1. Pre-Demonstration Study Activities and Completion Dates 5
Table 3-2. Evaluation Objectives and Supporting Data Collection Activities 5
Table 3-3. Sample Collection Schedule and Analyses 7
Table 4-1. Raw and Treated Water Quality Data 13
Table 4-2. Physical and Chemical Properties of G2 Media 15
Table 4-3. Design Specifications of the G2 Media System 17
Table 4-4. Summary of G2 Media Treatment System Operation 22
Table 4-5. Summary of Arsenic, Iron, and Manganese Analytical Results 25
Table 4-6. Summary of Water Quality Parameter Measurements 26
Table 4-7. Calculation of Acid Consumption for pH Adjustment at the WRWC Site 32
Table 4-8. Backwash Water Sampling Results 33
Table 4-9. Distribution System Sampling Results 35
Table 4-10. Capital Investment for the G2 Media Treatment System 36
Table 4-11. O&M Costs for the G2 Media Treatment System 37
vn
-------
ABBREVIATIONS AND ACRONYMS
Ap differential pressure
AA activated alumina
AAL American Analytical Laboratories
ADI ADI Group, Inc.
Al aluminum
AM adsorptive media
As arsenic
bgs below ground surface
BV bed volume(s)
C/F coagulation/filtration
Ca calcium
C12 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
gal gallons
GFH granular ferric hydroxide
GFO granular ferric oxide
gpd gallons per day
gpm gallons per minute
HOPE high-density polyethylene
HAMHP Holiday Acres Mobile Home Park
hr hours
ICP-MS inductively coupled plasma-mass spectrometry
ID identification
IX ion exchange
LCR (EPA) Lead and Copper Rule
MCL maximum contaminant level
MDL method detection limit
MDWCA Mutual Domestic Water Consumers Association
Mg magnesium
mg/L milligrams per liter
Hg/L micrograms per liter
min minutes
Vlll
-------
ABBREVIATIONS AND ACRONYMS (CONTINUED)
Mn
Mo
mV
manganese
molybdenum
millivolts
N/A not applicable
Na sodium
NA not available
NaOCl sodium hypochlorite
NHDES New Hampshire Department of Environmental Services
NRMRL National Risk Management Research Laboratory
NSF NSF International
NTU nephlemetric turbidity unit
O&M operation and maintenance
ORD Office of Research and Development
ORP oxidation-reduction potential
Pb lead
psi pounds per square inch
PO4 orthophosphate
PVC polyvinyl chloride
QA quality assurance
QA/QC quality assurance/quality control
QAPP Quality Assurance Project Plan
RPD relative percent difference
Sb antimony
SDWA Safe Drinking Water Act
SiO2 silica
SM system modification
SO4 sulfate
STMGID South Truckee Meadows General Improvement District
STS Severn Trent Services
TBD to be determined
TCLP Toxicity Characteristic Leaching Procedure
TDS total dissolved solids
TOC total organic carbon
TSS total suspended solids
V vanadium
VOC volatile organic compound
WRWC White Rock Water Company
IX
-------
ACKNOWLEDGMENTS
The authors wish to extend their sincere appreciation to the staff of C&C Water Services of Gilford and
Bow in New Hampshire. The C&C Water Services staff monitored the treatment system daily, and
collected samples from the treatment system and distribution system on a regular schedule throughout this
reporting period. This performance evaluation would not have been possible without their efforts.
-------
1.0 INTRODUCTION
1.1 Background
The Safe Drinking Water Act (SDWA) mandates that the 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 text 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 sites from a list of 115 sites to be the host sites for the
demonstration studies. Holiday Acres Mobile Home Park (HAMHP) in Allenstown, NH, was originally
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 from 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. The ADI G2 adsorptive media was
selected for the Allenstown site. In January 2004, HAMHP decided to withdraw from the demonstration
study due to the facility's decision to switch to an alternate public water supply source.
In March 2004, EPA decided to replace HAMHP with the White Rock Water Company (WRWC) public
water system, operated by C&C Water Services, serving the community of Village Shore Estates at Bow,
NH. Because the design flowrate for the WRWC system was about half of the flowrate at HAMHP, the
ADI adsorption system was re-configured to operate in series, increasing the empty bed contact time
(EBCT) from 18 to 32 min total (i.e., 16 min per vessel, two vessels in series).
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 (including arsenic, iron, and pH) of the 12 demonstration sites. The
technology selection and system design for the 12 demonstration sites have been reported in an EPA
report (Wang et al., 2004) posted on an EPA Web site (http://www.eap.gov/ORD/NRMRL/arsenic/
resource.htm).
-------
Table 1-1. Summary of 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
SM
AM (E33)
AM (E33)
AM (E33)
AM (AAFS50)
IX
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
(HS/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 Consumers Association
STMGID = South Truckee Meadows General Improvement District; WRWC = White Rock Water Company
(a) System reconfigured from parallel to series operation due to lower flowrate of 40 gpm at the WRWC site
(b) Arsenic exists mostly as As(III).
(c) Iron exists mostly as soluble Fe(II).
(d) Due to system reconfiguration from parallel to series operation, the design flowrate is reduced by 50%.
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 simplicity of required system operation and maintenance (O&M)
and operator's skill levels.
• Determine the capital and O&M costs of the technologies.
• Characterize process residuals produced by the technologies.
This report summarizes the results gathered during the first six months of the ADI system operation from
October 13, 2004 through April 24, 2005. The types of data collected include system operational data,
water quality data (both across the treatment train and in the distribution system), residuals
characterization data, and capital and preliminary O&M cost data.
-------
2.0 CONCLUSIONS
Based on the information collected during the first six months of system operation, the following
conclusions were made relating to the overall objectives of the treatment technology demonstration study.
Performance of the arsenic removal technology for use on small systems:
• Higher than 10 |o,g/L of arsenic breakthrough was observed after the lead vessel
throughout this study period. The arsenic concentration increased to 26.3 |o,g/L
after about 5,700 BVs of throughput. Elevated arsenic concentrations also were
measured after the lag vessel immediately after the system startup. The
concentration decreased to 1.7 |o,g/L and then increased to 5.8 |o,g/L at 5,700 BVs
of throughput. Lowering the pH values to as low as 6.1 did not appear to
improve the media performance.
• Increases in manganese and silica concentrations to as high as 35.8 |o,g/L and 61.8
mg/L, respectively, were observed in the treated water following the G2 media
treatment, indicating leaching of these constituents from the media. According to
the vendor, some arsenic and manganese existed as impurities in the FeCl3
solution used to produce the G2 media; silica was the base substrate of the G2
media. The concentrations of both manganese and silica leveled off after 2,000
to 3,000 BVs of throughput.
• Other than a few exceptions, arsenic, iron, and manganese concentrations in the
distribution system closely mirrored those measured after the treatment system.
A loss of pH control resulted in lower than normal pH values in the distrubution
system, causing a significant increase in the lead and copper levels with the
copper concentration at one location exceeding its action level of 1.3 mg/L.
• Total and free chlorine residuals measured before and after the adsorption vessels
were similar, indicating little or no chlorine consumption by the G2 media.
Required system O&Mand operator's skill levels:
• Generally, the operation of the treatment system did not require additional skills
beyond those necessary to operate the original treatment equipment used at the
site prior to the demonstration. The daily demand on the system operator was
typically about 20 min to inspect the system and record operational parameters.
Based on the size of the population served and the treatment technology, the
State of New Hampshire requires Level 1A Certification for operation of the
treatment system and is considering upgrading this requirement to Level 1
certification.
• A significant O&M issue for this system was the need for acid and caustic
addition to maintain the desired pH ranges of the feed water to the treatment
system and the finished water to the distribution system.
Process residuals produced by the technology:
• Residuals produced by the operation of the treatment system included backwash
water and spent media. Because the media was not replaced during the first six
months of system operation, the only residual produced was backwash water.
-------
Because the pressure drop across the vessels was low (i.e., 1-2 psi), the system
was backwashed only twice during the first six months of operation. Each
backwash event produced approximately 2,000 gal of wastewater per vessel.
Soluble arsenic concentrations in the backwash water from the lead vessel ranged
from 40.3 to 42.8 |o,g/L. Soluble arsenic concentrations in the backwash water
from the lag vessel ranged from 11.4 to 26.1 |o,g/L.
Cost-effectiveness of the technology:
Using the system's actual capacity of 40 gallons per minute (gpm) (57,600
gallons per day [gpd]), the capital cost was $3,868/gpm ($2.68/gpd) and
equipment-only cost was $2,565/gpm ($1.78/gpd). These calculations did not
include the cost of the building construction.
Although media replacement and disposal did not take place during the first six
months of operation, the cost to change out the lead vessel was estimated to be
$9,396 based on information provided by the vendor and a local subcontractor.
-------
3.0 MATERIALS AND METHODS
3.1
General Project Approach
Following the pre-demonstration activities summarized in Table 3-1, the performance evaluation study of
the ADI adsorption system began on October 13, 2004. Table 3-2 summarizes the types of data collected
and/or considered as part of the technology evaluation process. The overall performance of the system
was determined based on its ability to consistently remove arsenic to the target MCL of 10 |o,g/L; this was
monitored through the collection of biweekly and monthly 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.
Table 3-1. Pre-Demonstration Study Activities and Completion Dates
Activity
Introductory Meeting Held
Revised Vendor Quotation Submitted to Battelle
Purchase Order Modification Completed
Engineering Package Submitted to NHDES
Steel Floor for Treatment System Installed
Adsorption Vessels Delivered to Site
Permit Issued by NHDES
Draft Study Plan Issued
System Installation Completed
Final Study Plan Issued
Media Conditioning and System Shakedown Completed
Performance Evaluation Begun
Date
April 22, 2004
May 10, 2004
June 10, 2004
June 14, 2004
June 25, 2004
June 28, 2004
August 23, 2004
September 2, 2004
September 13, 2004
October 6, 2004
October 11, 2004
October 13, 2004
NHDES = New Hampshire Department of Environmental Services.
Table 3-2. Evaluation Objectives and Supporting Data Collection Activities
Evaluation Objectives
Performance
Reliability
Simplicity of Operation and
Operator Skill
Cost-Effectiveness
Residual Management
Data Collection
-Ability to consistently meet 10 jag/L of arsenic in effluent
-Unscheduled downtime for system
-Frequency and extent of repairs to include labor hours, problem description,
description of materials, and cost of materials
-Pre- and post-treatment requirements
-Level of system automation for data collection and system operation
-Staffing requirements including number of operators and labor hours
-Task analysis of preventive maintenance to include labor hours per month and
number and complexity of tasks
-Chemical handling and inventory requirements
-General knowledge needed of safety requirements and chemical processes
-Capital costs including equipment, engineering, and installation
-O&M costs including chemical and/or media usage, electricity, and labor
-Quantity of the residuals generated by the process
-Characteristics of the aqueous and solid residuals
-------
Simplicity of the system operation and the level of operator skill required were evaluated based on a
combination of quantitative data and qualitative considerations, including any pre-treatment and/or post-
treatment requirements, level of system automation, operator skill requirements, task analysis of the
preventive 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 on the system operation were recorded on an Operator Labor Hour Log Sheet.
The cost-effectiveness of the system is evaluated based on the cost per 1,000 gal ($/l,000 gal) of water
treated. This requires the tracking of capital costs such as equipment, engineering, and installation costs,
as well as O&M costs for media replacement and disposal, chemical supply, electrical power use, and
labor hours. The capital costs have been reported in an EPA report (Chen et al., 2004) posted on an EPA
Web site (http://www.epa.gov/ORD/NRMRL/arsenic/resource.htm). Data on O&M costs were limited to
chemicals, electricity, and labor hours because media replacement did not take place during the six
months of operation.
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 was sampled and analyzed for chemical characteristics.
3.2 System O&M and Cost Data Collection
The plant operator performed daily, weekly, and monthly system O&M and data collection following the
instructions provided by ADI and Battelle. On a daily basis, the plant operator recorded system
operational data, such as pressure, flowrate, totalizer, and hour meter readings on a System Operation Log
Sheet; checked the sodium hypochlorite, acid, and caustic drum levels; and conducted visual inspections
to ensure normal system operations. In the event of problems, the plant operator would contact the
Battelle Study Lead, who then would determine if ADI should be contacted for troubleshooting. The
plant operator recorded all relevant information on the Repair and Maintenance Log Sheet. Once a week
the plant operator measured water quality parameters, 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.
Capital costs for the ADI system consisted of costs for equipment, site engineering, and system
installation. The O&M costs consisted primarily of costs for the media replacement and spent media
disposal, chemical and electricity consumption, and labor. Chemical usage, including sodium
hypochlorite, acid, and caustic, and electricity consumption were tracked using the System Operation Log
Sheet. Labor hours for various activities, such as the routine system O&M, system troubleshooting and
repair, and demonstration-related work, were tracked using an Operator Labor Hour Log Sheet. The
routine O&M included activities such as completing the daily field logs; replenishing the sodium
hypochlorite, acid, and caustic solutions; ordering supplies; performing system inspections; and other
items as recommended by the equipment vendor. The demonstration-related work included activities
such as performing field measurements, collecting and shipping samples, and communicating with the
Battelle Study Lead. The demonstration-related activities were recorded but not included in the cost
analysis.
3.3 Sample Collection Procedures and Schedules
To evaluate the performance of the system, samples were collected from the source, treatment plant,
distribution system, and adsorptive vessel backwash. Table 3-3 provides the sampling schedules and
analytes measured during each sampling event. 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).
-------
Table 3-3. Sample Collection Schedule and Analyses
Sample
Type
Source
Water
Treatment
Plant Water
Distribution
Water
Backwash
Water
Residual
Sludge
Sample Locations'3'
Storage Tanks
After wells combined
(IN),
after chlorination and
pH adjustment (AP) ,
after Vessel A (TA),
and after Vessel B
(TB)
Three residences
previously used as
LCR sampling
locations
Sample ports on
backwash discharge
line from each vessel
Backwash discharge
area
No. of
Samples
1
4
3
2
2-3
Frequency
Once
during the
initial site
visit
Biweekly
Bimonthly
Monthly
During
each
backwash
event
TBD
Analytes
As(total), paniculate and
soluble As, As(III), As(V),
Fe (total and soluble), Mn
(total and soluble), Al (total
and soluble), Na, Ca, Mg,
V, Mo, Sb, Cl, F, SO4,
SiO2, PO4, TOC, alkalinity,
andpH.
On-site: pH, temperature,
DO/ORP, C12 (free and
total) (except IN location).
Off-site: As (total), Fe
(total), Mn (total), SiO2,
PO4, turbidity, and
alkalinity.
On-site: pH, temperature,
DO/ORP, and C12 (free and
total) (except IN location).
Off-site: As(total),
paniculate and soluble As,
As(III), As(V), Fe (total and
soluble), Mn (total and
soluble), Ca, Mg, F, NO3,
SO4, SiO2, PO4, turbidity,
and alkalinity.
pH, alkalinity, As, Fe, Mn,
Pb, and Cu.
TDS, turbidity, pH, As
(soluble), Fe (soluble), and
Mn (soluble)
TCLP Metals
Date(s) Samples
Collected
04/22/04
10/19/04, 10/26/04,
11/02/04, 11/16/04,
11/30/04,01/04/05,
01/18/05, 02/15/05,
03/01/05, 03/15/05,
04/12/05
10/13/04, 12/14/04,
02/01/05, 03/29/05
Baseline
sampling(b):
07/21/04, 08/05/04,
08/18/04, 09/08/04
Monthly sampling:
11/03/04, 12/08/04,
01/12/05, 02/09/05,
03/09/05, 04/20/05
01/11/05
04/12/05
TBD
(a) The abbreviation in each parenthesis corresponds to the sample location in Figure 4-5.
(b) Four baseline sampling events were performed before the system became operational.
TBD = to be determined.
-------
3.3.1 Source Water Sample Collection. During the initial visit to the WRWC site, Battelle
collected one set of source water samples for detailed water quality analyses. The source water also was
speciated for particulate and soluble As, iron (Fe), manganese (Mn), aluminum (Al), and As(III) and
As(V). The sample tap was flushed for several minutes before sampling; special care was taken to avoid
agitation, which might cause unwanted oxidation. Arsenic speciation kits and containers for water quality
samples were prepared as described in Section 3.4.
3.3.2 Treatment Plant Water Sample Collection. During the system performance evaluation
study, water samples were collected across the treatment train by the plant operator. Samples were
collected biweekly on an eight-week cycle. For the first three biweekly events, treatment plant samples
were collected at four locations (i.e., after wells combined [IN], after chlorination and pH adjustment
[AP], after Vessel A [TA], and after Vessel B [TB]), and analyzed for the analytes listed under the
biweekly treatment plant analyte list (see Table 3-3). Bimonthly (once every eight weeks) treatment
plant samples collected at the same four locations were speciated for arsenic and analyzed for the analytes
listed in Table 3-3 under "bimonthly." The sampling frequency was reduced from weekly as stated in the
Study Plan to biweekly following the first month of system operations.
3.3.3 Backwash Water Sample Collection. Two backwash water samples were collected on
January 11 and April 12, 2005 from the sample taps located at the backwash water effluent line from each
vessel. Unfiltered samples were measured on site for pH using a field pH meter, and a 1-gallon sample
was sent to American Analytical Laboratories (AAL) for total dissolved solids (TDS) and turbidity
measurements. Filtered samples using 0.45-(im filters were sent to Battelle's inductively coupled plasma-
mass spectrometry (ICP-MS) laboratory for soluble As, Fe, and Mn analyses. Arsenic speciation was not
performed for the backwash water samples.
3.3.4 Backwash Solid Sample Collection. Backwash solid samples were not collected in the
initial six months of this demonstration. Solid/sludge samples will be collected from the backwash
discharge during the second half of the demonstration. The solid/sludge samples will be collected in glass
jars and submitted to TCCI Laboratories for Toxicity Characteristic Leaching Procedure (TCLP) tests.
3.3.5 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 arsenic, lead, and copper levels. During July through September 2004,
prior to the startup of the treatment system, four baseline distribution system sampling events were
conducted at three locations within the distribution system. Following the startup of the arsenic
adsorption system, distribution system sampling continued on a monthly basis at the same three locations.
The three homes selected for the sampling had been included in the Lead and Copper Rule (LCR)
sampling in the past. The samples were collected following an instruction sheet developed according to
the Lead and Copper Rule Reporting Guidance for Public Water Systems (EPA, 2002). First-draw
samples were collected from cold-water faucets that had not been used for at least six hours to ensure that
stagnant water was sampled. The sampler 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. Analytes for the
baseline samples coincided with the monthly distribution system water samples as described in Table 3-3.
Arsenic speciation was not performed for the distribution water samples.
3.4 Sampling Logistics
All sampling logistics including arsenic speciation kits preparation, sample cooler preparation, and
sample shipping and handling are discussed as follows:
-------
3.4.1 Preparation of Arsenic Speciation Kits. The arsenic field speciation method used an anion
exchange resin column to separate the soluble arsenic species, As(V) and As(III) (Edwards et al., 1998).
Arsenic speciation kits 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. All sample bottles were new and contained appropriate
preservatives. Each sample bottle was taped with a pre-printed, colored-coded, and waterproof label.
The sample label consisted of sample identification (ID), date and time of sample collection, sampler
initials, location, sent to, analysis required, and preservative. The sample ID consisted of a two-letter
code for a specific water facility, the sampling date, a two-letter code for a specific sampling location, and
a one-letter code for the specific analysis to be performed. The sampling locations were color-coded for
easy identification. For example, red, orange, yellow, and green were used to designate sampling
locations for IN, AP, TA, and TB, respectively. Pre-labeled bottles were placed in one of the plastic bags
(each corresponding to a specific sampling location) in a sample cooler. When arsenic speciation samples
were to be collected, an appropriate number of arsenic speciation kits also were included in the cooler.
When appropriate, the sample cooler also was packed with bottles for the three distribution system
sampling locations and/or the two backwash sampling locations (one for each vessel).
In addition, a packet containing all sampling and shipping-related supplies, such as latex gloves, sampling
instructions, chain-of-custody forms, prepaid Federal Express air bills, ice packs, and bubble wrap, also
was placed in the cooler. Except for the operator's signature, the chain-of-custody forms and prepaid
Federal Express air bills had already been completed with the required information. The sample coolers
were shipped via Federal Express to the facility approximately one week prior to the scheduled sampling
date.
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 label identifications were checked against the chain-of-custody forms and the samples were
logged into the laboratory sample receipt log. Discrepancies, if noted, were addressed by the field sample
custodian, and the Battelle Study Lead was notified.
Samples for water quality analyses by Battelle's subcontract laboratories were packed in coolers at
Battelle and picked up by a courier from either AAL (Columbus, OH) or TCCI Laboratories (New
Lexington, OH). The samples for arsenic speciation analyses were stored at Battelle's ICP-MS
Laboratory. 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 are described in detail in Section 4.0 of the EPA-endorsed QAPP (Battelle,
2003). Field measurements of pH, temperature, and DO/ORP were conducted by the plant operator using
a WTW Multi 340i handheld meter, which was calibrated prior to use following the procedures provided
in the user's manual. The plant operator collected a water sample in a 400-mL plastic beaker and placed
the Multi 340i probe in the beaker until a stable, measured value was reached. The plant operator also
performed free and total chlorine measurements using Hach chlorine test kits.
Laboratory quality assurance/quality control (QA/QC) of all methods followed the guidelines provided in
the QAPP (Battelle, 2003). Data quality in terms of precision, accuracy, method detection limit (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 the Round 1 arsenic
study.
10
-------
4.0 RESULTS AND DISCUSSION
4.1
Facility Description
The WRWC public water system is operated by C&C Water Services and supplies water to 96 homes in
the community of Village Shore Estates at Bow, NH. The facility is located on a wooded lot at 6 Rocky
Point Drive, Bow, NH. Figure 4-1 shows the small underground structure that housed the existing water
system components prior to installation of the ADI adsorption system. The water source is groundwater
from three on-site bedrock wells (Wells 1, 2, and 3). The total flowrate from the three wells is
approximately 40 gpm at startup, based on the information provided by the plant operator. The well
pumps are activated based on the water level in two 15,000-gallon storage tanks (Figure 4-2) housed in a
separate underground structure located about 50 ft from the treatment and control structure. Prior to the
beginning of the demonstration study, the system was estimated to run approximately 6 to 8 hr per day
with an average daily use rate of 15,000 to 20,000 gpd. The existing treatment process included the
addition of a dilute sodium hypochlorite solution for disinfection and a caustic solution to raise pH to
make the treated water less corrosive in the distribution system. Approximately 10-15% of the total flow
also was treated with a small activated alumina (AA) system, shown in Figure 4-3, which had been at the
site for many years. The AA system was removed from the site prior to installation of the ADI adsorption
system.
Figure 4-1. Existing Underground Treatment and Control Structure
4.1.1 Source Water Quality. Source water samples were collected on April 22, 2004, and
subsequently analyzed for the analytes shown in Table 3-3. The results of the source water analyses,
along with those provided by the facility to EPA for the demonstration site selection and those obtained
from the New Hampshire Department of Environmental Services (NHDES) are presented in Table 4-1.
11
-------
Figure 4-2. Existing Storage Tanks in Underground Concrete Structure
Figure 4-3. Existing Activated Alumina System in the
Underground Treatment and Control Structure
12
-------
Table 4-1. Raw and Treated Water Quality Data
Parameter
Units
Sampling Date
PH
Total Alkalinity
Hardness (as
CaCO3)
Turbidity
Chloride
Fluoride
Sulfide
Sulfate
Nitrate-Nitrite
Silica (as SiO2)
Orthophosphate
TOC
As(total)
As (total soluble)
As (paniculate)
As(III)
As(V)
Total Fe
Soluble Fe
Total Al
Soluble Al
Total Mn
Soluble Mn
Total V
Soluble V
Total Mo
Soluble Mo
Total Sb
Soluble Sb
Total Na
Total Ca
Total Mg
-
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
W?/L
HB/L
W?/L
HB/L
W?/L
W?/L
HB/L
W?/L
HB/L
W?/L
W?/L
HB/L
W?/L
HB/L
HR/L
Mfi/L
Mfi/L
mg/L
mg/L
mg/L
U.S. EPA
Raw
Water
Data(a)
06/10/98
7.7
56.0
83.0
0.4
N/A
0.8
N/A
15.5
0.3
N/A
N/A
1.0
44.2
44.9
N/A
0.5
44.4
60.0
N/A
<400
N/A
25.0
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
24.7
5.2
Battelle
Raw
Water
Data
04/22/04
6.8
54.0
92.7
N/A
41.0
0.6
N/A
12.0
N/A
19.7
O.10
0.7
39.2
44.1
0.1
0.5
43.6
<25
<25
<10
<10
2.1
1.5
0.6
0.6
1.9
3.0
0.2
0.7
17.0
28.3
5.3
NHDES Raw
Water Data(b)
06/02
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.019-0.076
0.5
32-47
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
18.2-39.7
3.5-7.1
NHDES
Treated
Water Data(c)
12/29/99-
04/26/04
7.6-7.8
N/A
N/A
N/A
34-35
0.9-1.0
N/A
11-12
N/A
N/A
N/A
N/A
36.3-47
N/A
N/A
N/A
N/A
<50
N/A
N/A
N/A
<5
N/A
N/A
N/A
N/A
N/A
<3
N/A
16.6-17.5
N/A
N/A
(a) Results of source water sample collected in 1998.
(b) Raw water samples from Wells 1, 2, and 3 separately.
(c) Treated water samples are blended water from Wells 1, 2, and 3.
N/A = not analyzed.
Total arsenic concentrations of the source water ranged from 32 to 47 |o,g/L. Based on the April 22, 2004
sampling results, the majority of arsenic present was in the As(V) form, with only a small amount (0.5
Hg/L) present as As(III).
13
-------
The pH values of the raw water ranged between 6.8 and 7.7, higher than the desired range of 6.0 to 7.0
indicated by ADI for using the G2 media.
The concentrations of iron (<25 to 60 |o,g/L) and other ions in the raw water were sufficiently low that
pretreatment prior to the adsorption process was not required. The concentrations of orthophosphate and
silica also were sufficiently low (i.e., <0.1 mg/L and 19.7 mg/L, respectively) and, therefore, were not
expected to affect the As adsorption on the G2 media.
4.1.2 Pre-Demonstration Treated Water Quality. Table 4-1 presents historic data for several
analytes from treated water samples collected in compliance with the state monitoring and reporting
requirements. Because the treatment process prior to distribution included only chlorination and caustic
addition, concentrations of analytes in the treated water were very similar to those of the raw water. Total
arsenic concentrations in the treated water ranged from 36.3 to 47 |o,g/L. Iron and manganese
concentrations were below the respective detection limits of 50 and 5 (ig/L. The pH values of the treated
water ranged from 7.6 to 7.8.
4.1.3 Distribution System. The distribution system serving the community of Village Shore
Estates consists of a looped distribution line constructed primarily of polyvinyl chloride (PVC) pipe. The
connections to the distribution system and piping within the residences themselves are primarily PVC and
some copper pipe. It is believed that a few homes may have pipe with lead solder, and that no homes
have lead pipe.
Compliance samples from the distribution system are collected monthly for bacterial analysis and yearly
for volatile organic compounds (VOCs). Under the EPA LCR, samples are collected from customer taps
at five residences every three years.
4.2 Treatment Process Description
The ADI adsorption system uses G2 media for arsenic removal. The media consists of a granular,
calcined diatomite substrate coated with ferric hydroxide. Table 4-2 presents physical and chemical
properties of the media. The G2 media has NSF International (NSF) Standard 61 listing for use in
drinking water applications.
The ADI system is a fixed-bed downflow adsorption system. When the media reaches its capacity, the
spent media may be removed and disposed of after being subjected to the EPA TCLP test. The media
also can be regenerated using a 1% sodium hydroxide solution. However, due to the relatively small size
of the treatment facility, spent media will be removed and disposed of to simplify system operations.
The adsorption system at the WRWC site consists of two vertical, 72-inch-diameter and 72-inch-sidewall-
height cylindrical filter vessels, configured in series. The adsorption vessels were originally designed to
operate in parallel for HAMHP with a flowrate of 70 gpm (35 gpm per vessel). Due to the switch to the
site in Bow with a total flowrate of about 40 gpm, the flowrate was reduced by 43%; therefore, the system
was reconfigured to operate in series. As such, each vessel would provide for an EBCT of 16 min,
compared to the 18 min per vessel EBCT the system would have provided as originally designed for the
HAMHP site. Note that both of these EBCTs are much longer than the 10-min EBCT normally
recommended by the vendor. Additionally, the hydraulic loading rate of the system was increased
slightly from 1.2 to 1.4 gpm/ft2 with the switch from the HAMHP to the WRWC site. Both of these
loading rates are significantly lower than the 2.5 to 3.0 gpm/ft2 that would normally be applied to the G2
media. ADI recommended the use of 72-inch-diameter vessels with the intent of extending the media run
length for the HAMHP site. Figure 4-4 is a process flow diagram of the adsorption system supplied by
14
-------
Table 4-2. Physical and Chemical Properties of G2 Media
Physical Proi
Parameter
Matrix
Physical Form
Color
Bulk Density (lb/ft3)
Specific Gravity (dry)
Hardness (lb/in2)
Effective Size (mm)
Uniformity Coefficient
Bulk Relative Density
Adsorption (%)
oerties
Value
Diatomite impregnated with ferric
hydroxide
Dry granules
Dark brown
47
0.75
210
0.32
1.8-2.0
1.073
51.1
Ch emical An alysis
Constituents
Fe
Na
Al
Diatomaceous Earth (a silica based material)
Trace Elements
Weight %
5- 6
9-10
0.5
Balance
<0.1
Source: ADI
ADI. The design features of the treatment system are summarized in Table 4-3, and a flow diagram along
with the sampling/analysis schedule are presented in Figure 4-5. Key process components include:
• Intake. Raw water was pumped from the three on-site bedrock wells (Wells 1, 2,
and 3) and fed to the G2 media treatment system. The entry piping consisted of 2-
inch PVC pipe from the three supply wells, which were combined into a single line
located in the existing underground portion of the treatment building. The single line
extended up through an opening in the floor of the treatment building and connected
to the 3-inch entry point of the treatment system.
• Prechlorination. The existing sodium hypochlorite feed system was used to add
chlorine ahead of the adsorption vessels to prevent biological growth in the vessels
and maintain a target chlorine residual value of 0.5 mg/L in the distribution system
for disinfection purposes. The chorine addition system consisted of a LMI™ chlorine
metering pump, a 50-gallon high-density polyethylene (HDPE) chemical feed tank,
and polyethylene tubing to transfer the hypochlorite solution from the tank to the
injection point. The sodium hypochlorite solution was injected directly into the raw
water line after the wells were combined as described above. Operation of the
chlorine feed system was tied to the well pumps so that the chlorine injected only
when the wells were on. Chlorine consumption was measured using volumetric
markings on the outside of the feed tank.
15
-------
[
FROM SOURCE J> ~>*~
— €J> — |
H
1 • 1 N40CL
~~r "
V *RV1
TV- X—^-x
FILTER 1
i^H.SQ.
V2
f ^\_
V^PH J
_ r
ST5?
| '
1
p)
\y
^
v.
v3 V4 i^"~N
©
_-_r x-
0y~
^— , .
l__ I NcOH
A
•-©^
'
klvl
Ml
V5
'
THIS DOCUMENT AND THE INFORMATION, DESIGNS, j — ~^-
HEREIN ARE TH£ ^ROPtRfr Of AlX IM¥£RNAT
INC WD ARE SOLELY FOR US£ QN 6EHALF OP
AND ARE NOT TO 8£ DISCLOSED. COPIED OS
"OR ANY OT?CR ^UR^OSE. WHATSOEVER UNLES
SPECIFIC PE3uiss£QN rs F;RST OBTAINFO FR
FILTER MEDIA is AN AOI TRAD£ MARK AND PR
ONft I 9ACKWASH. WHILE. 6AC
JS£0 1 FOR MORF INFO'RMATI
S |
OM AN
J2»
OTEC*ED
HER
KWASMlNG OKI rtL1-
ivice PLEASE com
3N.
'
V^x p
OPTION
PORT
K~N
l — r M i
K-V
U2
FORE A
L«. THE
tCT AOI
f
\
H
t
LEGEND:
V 1 WANUA_
—£Xh— SLfTTERrt Y
I 1 — 1X3 SAMPLE TAP
4, 1 ST
WV3 \7 ^_ ANtrsEi)
{ AH ) I^D!CA~!NG.
PC )
ZJ
i^
V6
V9
(:
VI 0
\__y TRANSMITTER
l^^xl
f IL,I 1 IN-L NE
f^ ^^ IV_y1 'LOW METER
ARv1 *JR REIEASE
VALVC
FILTER 2 ,/— x
(PC ) PRES5URC
„ v_y c«t-
i?T\ METERING
^) PUWf5
va
^ —
7)
*~»- " .
V 1 1
1 0
2 X
3 0
4 X
5 X
6 X
7 0
5 X
5 X
:o 0
1 1 X
X 0 X X 0
0 X 0 X X
X X J! X Q
X X 0 X X
0 O X X X
Q 0 X X 0
X X * 1 0 X
0 x x j X 0
X X X | 0 X
X 0 XXX
X X 0 0 0
, — _,„,„ i
{^ ,e™, wiyj to,. j
jl, BBk •" AOI L 1 m f 1 • d
Jf\ JJf[ ^"l**son-^s-c^fsn_
ri;v;r«,rs?,:';f,'t«E~,r",!,'f"
PRELIMINARY
5^S~" STwtT"
" * JKH
2«e ^,(M 3-t,. 0.^^
BOW, NK
ARSENIC REMOVAL
SYSTEM
PROCESS FLOW
DIAGRAM
*"<"•*"* 4064-00!. I
""' "° FIGURE 1 | *" "" 0
"" NOT -0 SC«.E
Figure 4-4. Schematic of G2 Media Adsorption System (Provided by ADI)
-------
Table 4-3. Design Specifications of the G2 Media System
Parameter
Value
Remarks
Adsorption Vessels
Vessel Size (inch)
Cross-Sectional Area (ft2/vessel)
Number of Vessels
Configuration
72 D x 72 H
28.3
2
Series
-
-
-
-
Adsorptive Media
Media Type
Media Quantity (Ibs)
Media Volume (ft3)
Service
System Flowrate (gpm)
Hydraulic Loading Rate (gpm/ft2)
EBCT (mint/Vessel
Estimated Working Capacity (BV)
Throughput To Breakthrough (gal)
Average Use Rate (gal/day)
Estimated Media Life (months)
Pre-treatment
Post-treatment
Backwash
Backwash Frequency
Backwash Hydraulic Loading Rate
(gpm/ft2)
Backwash Flowrate (gpm)
Backwash Duration (min/vessel)
Wastewater Production (gal/vessel)
G2
8,000
170
40
1.4
16
10,300
6,550,000
15,000
14
NaCIO
H2SO4
NaOH
As needed
4
115
10-15
1,700
-
4,000 Ibs/vessel
36-inch bed depth or 85 ft3/vessel
System originally designed for 70 gpm at
HAMHP in Allenstown, NH
-
Total EBCT for both vessels -32 min
Vendor-provided estimate based on As
breakthrough at 10 (o,g/L in lead vessel with
incoming arsenic concentration at 39 (o,g/L
in source water
lBV=636gal
Based on ~6 hr of daily operation at 40
gpm.
Estimated frequency of media change-out
in lead vessel based on average throughput
to system.
Prechlorination
pH adjustment before adsorption
pH adjustment after adsorption
-
—
-
-
-
pH Adjustment Prior to Adsorption. The pH of the source water was adjusted
using a 93% sulfuric acid from an average of 7.3 to a target value of 6.8 then 6.4 in
order to increase the adsorption capacity of the media. The 93% sulfuric acid
solution was delivered to the site in 15-gal containers (200 Ib per container). The
acid was metered directly from these containers to the injection point using a
Prominent™ solenoid dosing pump. The acid was injected at a second injection point
located on the raw water line (after the wells are combined) just downstream of the
chlorine injection point described above. These injection points were installed about
3 ft apart and approximately 25 ft upstream of the adsorption system.
17
-------
Bimonthly
pH« temperature®, DO/ORP®,
As (total and soluble), As (III),
As (V), Fe (total and soluble), __
Mn (total and soluble),
Ca, Mg, F, N03, S04, SiO2, PO4,
turbidity, alkalinity
pH«, temperature®, DO/ORP®,
As (total and soluble), As (III),
As (V), Fe (total and soluble), __
Mn (total and soluble),
INFLUENT
(WELLS 1,2, AND 3)
White Rock Water Company
Public Water System in
Bow, NH
MEDIA G2® Technology
Design Flow: 40 gpm
DA: Cl,
pH ADJUSTMENT -
H2S04 INJECTION
Mn (total and soluble),
Ca, Mg, F, N03, S04, SiO2, PO4,
turbidity, alkalinity
pH«, temperature®, DO/ORP®,
As (total and soluble), As (III),
As (V), Fe (total and soluble), __
Mn (total and soluble),
Ca, Mg, F, N03, S04, SiO2, PO4,
turbidity, alkalinity
pH ADJUSTMENT -
NaOH INJECTION
DISTRIBUTION SYSTEM
Biweekly
pH®, temperature®,
DO/ORP®, As (total),
Fe (total), Mn (total), SiO2, PO4,
turbidity, alkalinity
pH®, temperature®,
DO/ORP®, As (total),
Fe (total), Mn (total), SiO2, PO4,
Ag, F, N03, S04, Si02, P04,
turbidity, alkalinity
SURFACE DRAINAGE/
LEACH FIELD
BACKWASH DISPOSAL
A
TCLP
i
pH, TDS, turbidity,
As (soluble) ./RW^ '
Fe (soluble), l^vvy --
Mn (soluble) / ME
* \
temperature®, DO/ORP®, \^
(total and soluble), As (III),
s (V), Fe (total and soluble), . jL
DIA\
SEE )
<
turbidity, alkalinity
LEGEND
| (iNJ After Wells Combined
^ (AP) After pH Adjustment
| (TAJ After Vessel A
| TTEJ After Vessel B
f BWJ Backwash Sampling Location
( SS 1 Sludge Sampling Location
INFLUENT Unit Process
DA: C12 Chlorine Disinfection
^- Process Flow
pH®, temperature®,
DO/ORP®, As (total),
Fe (total), Mn (total), SiO2, PO4,
turbidity, alkalinity
pH®, temperature®,
DO/ORP®, As (total),
' Fe (total), Mn (total), SiO2, PO4,
turbidity, alkalinity
Figure 4-5. Process Flow Diagram and Sampling Locations
18
-------
• Arsenic Adsorption. The two 72-inch-diameter, 72-inch-sidewall-height vessels
were constructed of 304 stainless steel and rated for 50 pounds per square inch (psi)
working pressure. The system was delivered to the site with a pre-assembled pipe
and valve manifold consisting of 3-inch schedule 80 PVC with flanged and solvent
weld connections. The manifold was mounted directly on a uni-strut steel frame
bolted directly to the front of the adsorption vessels as shown in Figure 4-6. Inlet and
outlet pressure gauges, PVC manually-actuated butterfly valves, air release/vacuum
valves, and sampling ports were installed as part of the pre-assembled unit. There
were no automated controls included as part of the adsorption system; all valves were
manually actuated. Initiation of system backwash or other operational adjustments
required manual adjustment of valves. Two inline pH probes were installed in the
piping manifold in order to measure the pH values of the water following the acid
and caustic addition. Additionally, a pH chart recorder was installed for continuous
logging of the inline probe readings. The addition of the acid and caustic was flow
paced based on a 4-20 mA control signal from a flowmeter located on the treated
water line downstream of the adsorption system. Each vessel contained about 85 ft3
of G2 media.
• pH Adjustment Prior to Storage and Distribution. After passing through the
adsorption vessels, the pH values of the treated water were adjusted using a 25%
NaOH solution to raise the pH value from about 6.5 to a target value of 7.5 before
going to the storage tanks and distribution system. The pH was increased to reduce
the tendency for dissolution of metals, especially lead and copper, from distribution
piping. The 25% NaOH solution was delivered to the site in 15-gal containers (160
Ib per container). The caustic solution was metered directly from these containers to
the injection point using a Prominent™ solenoid dosing pump. The injection point
was located downstream of the adsorption system and before the treated water went
out to the 15,000-gal storage tanks.
Figure 4-6. ADI G2 Media Arsenic Adsorption System
19
-------
4.3
System Installation
The installation of the treatment system at the site was completed in September 2004; shakedown and
startup activities continued into October 2004. The system installation and building construction
activities were carried out by the plant operator, C&C Water Services, as a subcontractor to ADI.
4.3.1 Permitting. Engineering plans for the system permit application were prepared by Lewis
Engineering, an ADI subcontractor located in Litchfield, NH. The plans included diagrams and
specifications of the G2 media treatment system, as well as site drawings showing the proposed layout of
the new treatment building. The plans were submitted to the NHDES (Water Supply Engineering
Bureau) for review and approval on June 14, 2004. The NHDES issued a letter of approval on August 23,
2004. The state did not issue a separate permit for discharging the system backwash water at the time of
start-up.
4.3.2 Building Construction. To house the G2 media treatment system, C&C Water Services
constructed an aboveground addition to the existing underground pump house structure (Figure 4-1).
Construction included placement of steel support beams on top of the existing concrete structure, and
construction of a wood frame building on the steel supports. The new building is roughly the same size
as the existing structure, approximately 20 ft by 22 ft. A photograph of the aboveground addition to the
treatment building is shown in Figure 4-7. Building construction began on June 16, 2004 with placement
of the steel support beams and continued through the end of August 2004, including placement and
setting of the vessels, which were put into place before completing the walls and roof of the new
treatment building.
Figure 4-7. New Treatment Building Addition
20
-------
4.3.3 Installation, Shakedown, and Startup. The adsorption vessels arrived on site and were
placed on the steel supports of the new treatment building on June 28, 2004. During shipment, some
minor damage was made to welds on the bottom flanges of both vessels. The manufacturer arranged for
repair of the welds by a local certified welding shop. C&C Water Services performed the system
installation, including all plumbing, mechanical, and electrical work. Installation of system piping was
completed on September 2, 2004.
The G2 media was loaded into the vessels on September 13, 2004. Prior to system startup, the media was
first backwashed at 115 gpm for about 1 hr to remove media fines in the bed. The G2 media was then
conditioned using a downflow acid rinse to neutralize the pH of the media from about 12 as a result of the
manufacturing process. To minimize the amount of wastewater produced, conditioning was done by
recirculating the rinse water through each vessel at a flowrate of 70 gpm using a 5-hp pump. Meanwhile,
a chemical metering pump was used to add a 93% sulfuric acid solution at the inlet of each vessel. Each
vessel was conditioned separately for two 8-hr days and the total acid consumption was about 3 gal per
vessel (or 6 gal total). The volume of wastewater produced per vessel was equivalent to the volume of
water required to fill one vessel and some additional piping (i.e., about 1,500 gal). The wastewater (about
3,000 gal per vessel over the two-day period) was discharged to a rip-rap lined surface drainage area near
the treatment building at the end of each day. The pH of the wastewater as it was discharged ranged from
about 10 on the first day to 7 on the second.
Because of some delay in receiving the required components for the recirculation pump, the media
conditioning did not begin until September 28, 2004 and continued for about four days. The system was
put into service and the performance evaluation study officially began on October 13, 2004. A Battelle
staff member visited the site on this date to inspect the system, provide operator training for data and
sample collection, and collect the first set of samples from the treatment system.
4.4 System Operation
4.4.1 Operational Parameters. The operational parameters of the system are tabulated and
attached as Appendix A. Key parameters are summarized in Table 4-4. From October 13, 2004 through
April 24, 2005, the treatment system operated for 1,741 hr based on the well pump hour meter readings
collected daily at the well head. The operational time represented a utilization rate of approximately 38%
over the 28-week period with the supply wells operating at an average of 9.3 hr per day. The total system
throughput from October 13, 2004 through April 24, 2005 was approximately 3,858,000 gal based on the
flow totalizer readings from the finished water magnetic meter. This corresponds to 6,067 bed volumes
(BVs) of water processed through the system. The average flowrate through the system was 40.8 gallons
per minute (gpm) with an average EBCT of 31.7 min total or approximately 16 min per vessel.
Pressure loss across the vessels averaged less than 1 psi across the lead vessel and less than 2 psi across
the lag vessel for the first 28 weeks of operation. Because the pressure drop observed was low and did
not change significantly during system operation, the system was backwashed only twice during this
period.
During the first 28 weeks of operation, the system experienced some operational problems with the inline
pH meters. In general, the inline probe located after the acid addition upstream of the adsorption vessels
read approximately 0.4 pH units lower than the corresponding measurements using a WTW field pH
probe. The inline probe located after the caustic addition following the adsorption vessels typically read
about 1.3 pH units higher than the corresponding measurements using the same field pH probe. The field
21
-------
Table 4-4. Summary of G2 Media Treatment System Operation
Total Operating Time (hr) -
October 13, 2004 to April 24, 2005
Average Daily Operating Time (hr/day)
Throughput (kgal)
Throughput (BV)
Average Flowrate (gpm)
Range of Flowrate (gpm)
Average EBCT (min)(a)
Range of EBCT (min)(a)
Average Differential Pressure Loss across
Vessel A (psi)
Average Differential Pressure Loss across
Vessel B (psi)
1741
9.3
3,858
6,067
40.8
10.6-49.0
31.7
26 - 120
0.8
1.8
(a) Calculated based on 170 ft of media total (85 ft in each vessel;
vessels in series).
pH readings after caustic addition were, in most cases, close to the pH readings of distribution water
samples measured by AAL (6.4 to 7.8 with the field probe vs. 6.6 to 8.1 in the distribution samples),
suggesting that the field pH probe was more accurate than the inline probes.
Although several attempts were made by the plant operator and ADI to correct the problems associated
with the inline probes (including cleaning and calibrating the probes, consulting with the vendor and
manufacturer, switching the "acid" inline probe [which seemed to read more accurately] with the
"caustic" inline probe, and conducting an on-site service call by ADI to investigate and replace the "acid"
inline probe with a new probe), correlation between the inline pH meters and the field meter continued to
be poor throughout the first 28 weeks of operation.
4.4.2 Backwash. During the first six months of system operation, the system was backwashed
twice, one time each on January 11, 2005 and April 12, 2005 after about three and six months of system
operation, respectively. Backwash was performed manually using finished water from the storage tanks.
During backwash, the system was taken off-line and treated water was drawn via a booster pump from the
storage tanks at a flowrate of approximately 115 gpm (or about 4 gpm/ft2). The backwash lasted for 20
and 10 min per vessel during the first and second backwash events, respectively, producing approximately
2,200 and 1,200 gal of wastewater for each vessel.
4.4.3 Residuals Management. Residuals produced by the operation of the treatment system
include spent media and backwash water. The media was not exhausted during the first six months of
system operation; therefore, the only residual produced was backwash water. Backwash water is
discharged to a rip-rap lined surface drainage and allowed to infiltrate into the ground.
4.4.4 System Operation Reliability and Simplicity. A significant O&M issue for this system was
the need for acid and caustic addition to maintain the desired pH values of the feed water to the treatment
system and the finished water to the distribution system. Confounding the proper dosing of acid and
caustic were the continuing discrepancies observed in pH readings from the inline probes versus the field
probe as discussed in Section 4.4.1. Further discussion on the impact of pH adjustment in the distribution
system is included in Section 4.5.3. The system did not experience any unscheduled downtime during the
first six months of operation.
22
-------
Additional discussion regarding system operation and operator skill requirements are provided below in
relation to pre- and post-treatment requirements, levels of system automation, operator skill requirements,
preventive maintenance activities, and frequency of chemical/media handling and inventory requirements.
Pre- and Post-Treatment Requirements. Pre-treatment consisted of the addition of a 6% sodium
hypochlorite solution for disinfection, which was already performed at the site prior to the installation of
the arsenic treatment system, and a 93% sulfuric acid solution for lowering the water pH in order to
maximize the arsenic removal capacity of the G2 media. Post-treatment included the addition of a 25%
NaOH solution to raise the pH values back to approximately 7.5 to reduce corrosivity prior to entering the
storage tanks and distribution system. The rate of chemical consumption is provided below under
chemical handling and inventory requirements.
System Controls. The G2 media adsorption system was a passive system, requiring only the operation of
the well pumps and chemical metering pumps for chlorination and acid and caustic addition. The
adsorption system itself required no automated parts and all valves were manually activated. Power
supply to the chemical metering pumps was tied into the supply well pumps so that when the supply wells
were started, triggered by a level switch in the storage tanks, the chemical metering pumps also were
energized to dispense chlorine, acid, and caustic at a pre-determined rate. The system had the capability
to adjust the chemical feed rates based on the inline probe readings to maintain a specified pH value;
however, this control setup was disabled during the first 6 months of the demonstration period. The acid
and caustic feed rates were controlled by manually setting the pump stroke-length and automatically
pacing the pump based on a 4-20 mA control signal provided by a Badger™ magnetic flowmeter located
on the treated water line. Additionally, a two-pen pH chart recorder was installed for continuous logging
of the pH values after the acid and caustic addition. Although useful for tracking the operation of the
system, the pH chart recorder proved somewhat problematic to operate as it was initially installed without
the proper relays to allow it to communicate with the inline pH probes. As a result, the system operated
for several weeks with the pH recorder giving erroneous readings. In early January 2005, the proper
relays were installed and the chart recorder was adjusted so that the readings better reflected the inline
probe readings. However, the inline probes continued to give erroneous readings as described in Section
4.4.1. Backwash cycles were initiated manually and required the operator to adjust system valves
accordingly prior to initiating the system backwash.
Operator Skill Requirements. Generally, the operation of the treatment system did not require additional
skills beyond those necessary to operate the original treatment equipment used at the site prior to the
demonstration. The daily demand on the system operator was typically about 20 minutes to visually
inspect the system and record operating parameters such as totalizer and hour meter readings, flowrates,
and system pressure readings on the field log sheets. Based on the size of the population served and the
treatment technology, the State of New Hampshire requires Level 1A Certification for operation of the
treatment system and is considering upgrading this requirement to Level 1 certification.
In addition to the standard checks and data recording performed daily for the system, C&C water services
personnel typically spent 3-4 hr per week troubleshooting various problems associated with the system,
especially during the first few months of the system operation. Primarily this time was spent making
adjustments to the acid and caustic addition. Because the system was not set to make these adjustments
automatically, all adjustments were made by manually adjusting the stroke-length of the chemical
metering pumps. Adding to the complexity of achieving the proper balance of acid and caustic addition
was the disagreement in readings between the inline pH probes and the WTW field probe, as discussed in
Section 4.4.1. In early December, acid addition was increased to further lower the pH of the feed water to
attempt to increase arsenic removal by the G2 media. To counterbalance this increase in acid addition,
intuitively, the caustic addition also would have to be increased. In fact, in late December, the caustic
metering pump was inadvertently ramped down such that the pH values of water going to the storage
23
-------
tanks were lower than what had been measured historically at the site. The drop in pH values was
noticeable in the subsequent distribution system samples collected on January 12, 2005. Further
discussion on the impact of this pH drop in the distribution system is included in Section 4.5.3.
Preventive Maintenance Activities. Regular maintenance activities required for the operation of the G2
media treatment system consisted primarily of daily visual inspection of the system to ensure that it
appeared to be operating appropriately, maintaining chemical supply for feed chemicals, collecting
routine water samples, cleaning and calibrating the inline pH probes, and system backwashing as
necessary.
Chemical/Media Handling and Inventory Requirements. Chemicals required for system operation
included a 6% sodium hypochlorite, a 93% sulfuric acid, and a 25% NaOH solution. Proper handling and
storage of these chemicals were required, including secondary containment for the chemical storage area
and proper safety equipment for plant operators, including eye wash station and use of personal protective
equipment (gloves, chemical apron, and faceshield as required). During the first 28 weeks of system
operation, approximately l!/2 to two 15-gal containers (160 Ib per container) of 25% NaOH and one 15-
gal container (200 Ib per container) of 93% sulfuric acid were consumed per month for pH control
purposes. The average chemical consumption was 0.24 Ib/1,000 gal of water treated for sulfuric acid and
0.45 lb/1,000 gal for NaOH.
Media change-out was not required during the first six months of operation; thus, no additional media
handling was required after the initial installation.
4.5 System Performance
The system performance was evaluated based on analyses of samples collected from the raw and finished
water from the treatment plant, backwash lines, and distribution system.
4.5.1 Treatment Plant Sampling. Water samples were collected at four locations through the
treatment train: at the inlet (IN), after chlorination and pH adjustment (AP), at the effluent of Vessel A
(TA), and at the effluent of Vessel B (TB). Field-speciated samples at each location were collected once
every eight weeks throughout this reporting period. Table 4-5 summarizes the arsenic, iron, and
manganese analytical results. Table 4-6 summarizes the results of other water quality parameters.
Appendix B contains a complete set of 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. The key parameter for evaluating the effectiveness of the G2 media treatment system was the
concentration of arsenic in the treated water. The treatment plant water was sampled on 15 occasions
during the first six months of system operation, with field speciation performed on four of the 15
occasions. Samples were collected at all four sampling locations (IN, AP, TA, and TB) at each of the 15
sampling events.
Figure 4-8 contains four bar charts showing the concentrations of total As, particulate As, As(III), and
As(V) at the IN, AP, TA , and TB locations for each of the four field speciation events. Total arsenic
concentrations in raw water ranged from 38.0 to 91.3 |o,g/L and averaged 49.3 |o,g/L (Table 4-5). As(V)
was the predominating species, ranging from 47.5 to 54.1 |o,g/L and averaging 50.9 |o,g/L. Only trace
amounts of As(III) existed with concentrations averaging 0.6 |o,g/L. Particulate As also was low with
concentrations typically less than 1 |o,g/L. During the system startup on October 13, 2004, an unusually
high concentration of particulate As (i.e., greater than 40 |o,g/L, or almost 50% of total As) was measured.
It was not clear why such a high particulate As concentration was detected during this sampling event.
24
-------
Table 4-5. Summary of Arsenic, Iron, and Manganese Analytical Results
Parameter
As (total)
As (total
soluble)
As
(paniculate)
As(III)
As(V)
Total Fe
Dissolved Fe
Total Mn
Dissolved
Mn
Sampling
Location
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
Units
Hg/L
ug/L
ug/L
ug/L
ug/L
Hg/L
ug/L
Hg/L
H8/L
Hg/L
Ug/L
Hg/L
Hg/L
Ug/L
Hg/L
ug/L
Hg/L
ug/L
ug/L
Hg/L
ug/L
Ug/L
ug/L
ug/L
Ug/L
ug/L
HS/L
Ug/L
Hg/L
Hg/L
ug/L
Hg/L
Hg/L
ug/L
ug/L
Hg/L
Number of
Samples
1?(a)
17(a)
17(a)
1?(a)
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
1?(a)
1?(a)
17(a)
17(a)
4
4
4
4
1?(a)
17(a)
17(a)
1?(a)
4
4
4
4
Minimum
Concentration
38.0
38.7
12.6
1.7
48.2
49.7
15.5
3.6
<0.1
<0.1
<0.1
<0.1
0.5
0.5
0.4
0.4
47.5
49.1
14.8
3.0
<25
<25
<25
<25
<25
<25
<25
<25
0.12
<0.1
0.49
<0.1
0.44
0.32
1.15
1.32
Maximum
Concentration
91.3
96.1
37.5
50.9
54.6
55.7
25.3
14.3
40.8
43.8
12.2
47.2
0.7
0.6
0.8
1.1
54.1
55.1
24.5
13.1
22.1
60.0
<25
39.0
<25
<25
<25
<25
2.0
7.2
27.0
35.8
1.2
1.0
9.0
12.5
Average
Concentration
49.3
50.1
_(b)
_(b)
51.5
53.0
_(b)
_(b)
10.4
11.1
_(b)
_(b)
0.6
0.6
_(b)
_(b)
50.9
52.5
_(b)
_(b)
13.1
15.3
<25
14.1
<25
<25
<25
<25
0.9
1.4
_(b)
_(b)
0.6
0.6
_(b)
_(b)
Standard
Deviation
11.7
12.8
_(b)
_(b)
2.8
2.6
_(b)
_(b)
20.3
21.8
_(b)
_(b)
0.1
0.1
_(b)
_(b)
2.9
2.7
_(b)
_(b)
2.3
11.5
0.0
6.4
0.0
0.0
0.0
0.0
0.6
1.7
_(b)
_(b)
0.4
0.3
_(b)
_(b)
(a) Including two duplicate samples
(b) Average concentration and standard deviation not calculated. See Figures 4-9 and 4-10 for As and Mn
breakthrough curves.
Note: One-half of the detection limit was used for samples with concentrations less than the detection limit for
calculations. Duplicate samples were included in the calculations.
25
-------
Table 4-6. Summary of Water Quality Parameter Measurements
Parameter
Alkalinity
Fluoride
Sulfate
Orthophosphate
(as PO4)
Silica
Nitrate (as N)
Turbidity
pH
Temperature
Dissolved
Oxygen
ORP
Sampling
Location
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
IN
AP
TA
TB
Units
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
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
NTU
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
Number
of
Samples
jg(a)(b)
17(b)
17(b)
1?(b)
4
4
4
4
4
4
4
4
17(b)
17(b)
17(b)
17(b)
17(b)
17(b)
17(b)
17(b)
4
4
4
4
17(b)
17(b)
17(b)
17(b)
15
15
15
15
15
15
15
15
13
13
13
13
14
14
14
14
Minimum
Concentration
55
28
29
28
0.7
0.7
0.7
0.3
11
26
12
9.6
0.05
O.05
0.05
0.05
18.7
18.5
21.1
23.5
0.2
0.1
0.2
0.2
O.I
0.1
O.I
0.1
6.8
6.1
6.1
6.1
11.5
11.5
11.2
11.2
4.5
2.9
3.5
3.5
195
190
183
173
Maximum
Concentration
77
61
62
68
1.1
1.0
1.1
0.8
24
51
48
48
0.06
O.06
0.06
0.06
21.4
21.4
50.8
61.8
1.0
0.5
1.3
1.4
1.1
0.5
0.6
0.5
7.8
7.8
7.9
8.0
12.4
12.7
12.9
13.0
6.8
5.6
5.3
5.4
498
607
610
608
Average
Concentration
65.1
(c)
_(<0
_(<0
0.91
0.93
0.87
0.66
14.3
_(<0
_(<0
(c)
0.03
0.03
0.03
0.03
19.7
19.8
(c)
_(<0
0.41
0.24
0.48
0.52
0.31
0.18
0.16
0.20
7.3
_(<0
_(<0
(c)
11.9
11.9
11.8
11.7
5.6
4.2
4.3
4.4
233
435
471
484
Standard
Deviation
5.4
_(<0
_(<0
(c)
0.16
0.14
0.17
0.25
6.5
_(<0
_(<0
_(<0
0.00
0.00
0.00
0.00
0.7
0.7
_(<0
(c)
0.40
0.15
0.55
0.59
0.31
0.16
0.16
0.16
0.21
(c)
_(<0
_(<0
0.27
0.35
0.41
0.47
0.73
0.65
0.51
0.47
77.1
172.8
172.7
158.8
26
-------
Table 4-6. Summary of Water Quality Parameter Measurements (Continued)
Parameter
Free C12
Total C12
Total
Hardness
(as CaCO3)
Sampling
Location
AP
TA
TB
AP
TA
TB
IN
AP
TA
TB
Units
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Number
of
Samples
15
15
15
15
15
15
4
4
4
4
Minimum
Concentration
0.1
0.1
0.1
0.1
0.1
0.1
84.0
81.5
85.0
86.8
Maximum
Concentration
0.7
0.5
0.6
0.5
0.4
0.5
163.3
128.5
166.6
101.8
Average
Concentration
0.3
0.2
0.2
0.3
0.2
0.2
108.7
100.5
111.6
94.2
Standard
Deviation
0.2
0.1
0.1
0.1
0.1
0.1
36.7
20.0
37.3
7.1
(a) Two outlying alkalinity values, 254 mg/L (as CaCO3) measured on November 16, 2004 and 120 mg/L (as
CaCO3) measured on March 1, 2005, were excluded from this summary table.
(b) Including two duplicate samples
(c) Average concentration and stand deviation not calculated. See Figures 4-11 and 4-12 for alkalinity, sulfate, pH,
and silica measurements.
Note: One-half of the detection limit was used for samples with concentrations less than the detection limit for
calculations. Duplicate samples were included in the calculations.
The arsenic concentrations measured during this six-month period were generally consistent with those in
the raw water sample collected on April 22, 2004 (Table 4-1).
As expected, arsenic concentrations at the AP location were similar to those in the raw water. Because
the majority of arsenic present in raw water was already in the As(V) oxidation state, chlorination had
little or no effect on the concentration or oxidation state of arsenic entering the adsorption vessels.
Similar to those at the IN location, total arsenic concentrations at the AP location ranged from 38.7 to
96.1 |o,g/L and averaged 50.1 |og/L.
Free and total chlorine levels were measured at the AP, TA, and TB locations. Free chlorine levels were
measured at 0.1 to 0.7 mg/L at the AP location, with total chlorine levels ranging from 0.1 to 0.5 mg/L
(Table 4-6). The residual chlorine levels measured after each vessel at the TA and TB locations were
very similar to those measured at the AP location, indicating little or no chlorine consumption by the G2
media.
Total As concentrations after the lead (A) and lag (B) vessels are plotted against the BVs of water treated
in Figure 4-9. The figure also shows the total As concentrations in the source water and after
prechlorination and pH adjustment. After the lead vessel, greater than 30 |o,g/L of total As was
unexpectedly detected in samples collected just after startup on October 13 and about one week later on
October 19, 2004. After about 380 BVs of throughput, total As concentrations decreased to 12.6 to 15.6
|o,g/L before beginning a steady increase at about 2,600 BVs to 26.3 |o,g/L by April 12, 2005. Total As
concentrations after the lag vessel also were high during the first two weeks of system operation, with
16.7 to 21.8 ng/L of arsenic measured on October 13 and October 19, 2004, respectively. Afterwards,
the concentrations dropped to 1.7 |o,g/L after about 2,500 BVs and then increased steadily to 5.8 |o,g/L after
about 5,700 BVs by April 12, 2005.
Total As concentration measured after the lag vessel (B) on December 14, 2004 was unusually high at
50.9 |og/L, of which 47.3 |o,g/L existed as particulate As (See Figure 4-8). It was not clear what caused the
elevated particulate As concentration.
27
-------
Arsenic Species at the Inlet (IN)
Arsenic Species after Lead Vessel (TA)
to
oo
90 -
80 -
3" 70-
"3>
IT 60 -
0
5 «-
3
JJ 30
c 40
0
O
» 30
20
10
DAs (particulate)
• As(V)
• As (III)
^^^
90-
80-
? 70-
^ 60-
O
0)
C 40 -
8
3. 3°-
20-
10-
0 -
DAs (particulate)
• As(V)
• As (III)
2/1/2005 3/29/2005
Vessel (TB)
DAs (particulate)
DAs(V)
• As (III)
12/14/2004 2/1/2005
Date
12/14/2004 2/1/2005
Date
Figure 4-8. Concentration of Arsenic Species at the IN, AP, TA, and TB Sampling Locations
-------
Total Arsenic Results for Bow, NH
-•-Inlet
X After Prechlorination
-•-Vessel A
-A-VesselB
Bed Volumes of Water Treated (*103)
Figure 4-9. Total Arsenic Breakthrough Curves
ADI attributed the elevated arsenic concentrations just after system startup to the leaching of arsenic from
the G2 media prepared with FeCl3 containing arsenic and manganese as impurities. While this might
explain the elevated arsenic levels observed in the treated water during the first two weeks of system
operation, it did not explain why the arsenic concentrations remained high (i.e., 12.6 |o,g/L or greater)
following the lead vessel throughout the first six months of system operation.
Iron. Iron concentrations in the source water were low. With the exception of only a few data points, the
iron concentrations, both total and dissolved, were less than the detection limit of 25 |o,g/L at all sampling
locations throughout the first 6 months of system operation (Table 4-5).
Manganese. Treatment plant water samples were analyzed for total Mn during all sampling events and
for soluble Mn during speciation sampling events. Figure 4-10 shows the total manganese concentrations
over time at each of the four sampling locations across the treatment train. Similar to iron, manganese
concentrations in the raw water were low, ranging from 0.12 to 2.0 |o,g/L (Table 4-5). However,
manganese concentrations in the treated water following the lead and lag vessels were significantly
elevated to over 35 |o,g/L after the system start-up, apparently due to the leaching of manganese from the
media. After about 3,000 BVs, manganese concentrations following the lead and lag vessels decreased to
levels similar to those in the raw water.
Other Water Quality Parameters. The results of other water quality parameters are included in Appendix
B and are summarized in Table 4-6. Figure 4-11 presents the results of pH, alkalinity, and sulfate
measurements collected across the treatment train.
The first few samples taken during October 13 through November 2, 2004 showed somewhat erratic pH
results across the treatment train, which were thought to have been caused, in part, by erroneous on-site
29
-------
Total Manganese Results for Bow, NH
10/10/04
10/31/04
11/21/04
12/12/04
1/2/05 1/23/05 2/13/05
Date
3/6/05
3/27/05
4/17/05
Figure 4-10. Total Manganese Concentrations Over Time
measurements using the WTW handheld meter. The plant operators were retrained for the use of the
meter on November 9, 2004 and the results obtained since then appeared to follow a steadier trend.
The pH values of the source water typically ranged from 7.3 to 7.5. At the suggestion of ADI, the target
pH value for the feed water was set at 6.8 at the system start up and then reduced to 6.4 by mid-November
2004. The target pH value for the treated water following caustic addition was set at 7.5. For the most
part, the measured pH values after the acid addition and after Vessels A and B were very close to the
target value of 6.8 and later 6.4. The measured pH values after the caustic addition, however, deviated by
as much as 1.0 pH unit from the target value of 7.5. As described under Operator Skill Requirements in
Section 4.4.4, the operator had some difficulties in adjusting the rate of caustic addition to account for the
increased acid addition.
From early December 2004 through April 2005, the sulfuric acid consumed to lower the pH of the source
water from 7.5 to 6.4 was 0.26 lb/1,000 gal of water treated (or 31 mg/L) based on the amount of acid
used and the volume of water treated during this period. This consumption rate matched that of a
theoretical calculation using the method described by Rubel (2003) as shown in Table 4-7.
Alkalinity readings of the source water ranged from 55 to 77 mg/L (as CaCO3) and averaged 65.1 mg/L.
After the acid addition, the decreases in alkalinity ranged from 24 to 38 mg/L (as CaCO3) and averaged
31.8 mg/L (as CaCO3). This amount matched the 30 mg/L (as CaCO3) decrease as shown in Table 4-7.
Sulfate concentrations in the source water ranged from 11 to 24 mg/L and averaged 14.3 mg/L.
Immediately after the system start up, sulfate concentrations were reduced to 12.0 and 9.6 mg/L following
the lead and lag vessels, respectively, apparently being removed by the G2 media. Since the adjustment
30
-------
pH Values for Bow, NH
-•-Inlet
-x- After Acid Addition
-•-Vessel A
-A-Vessel B
-•-After Caustic Addition
10/10/04 10/31/04 11/21/04 12/12/04 1/2/05 1/23/05 2/13/05 3/6/05 3/27/05 4/17/05
Date
Alkalinity Values for Bow, NH
90-
80-
n 60-
O
-Inlet
After Acid Addition
-Vessel A
-Vessel B
10/10/04 10/31/04 11/21/04 12/12/04 1/2/05 1/23/05 2/13/05 3/6/05 3/27/05 4/17/05
Date
Sulfate Values for Bow, NH
-Inlet
-After Acid Addition
-Vessel A
-Vessel B
10/10/04 10/31/04 11/21/04 12/12/04 1/2/05 1/23/05 2/13/05 3/6/05 3/27/05 4/17/05
Date
Figure 4-11. pH, Alkalinity, and Sulfate Values over Time
31
-------
Table 4-7. Calculation of Acid Consumption for pH Adjustment at the WRWC Site
Parameter
pH (S.U.)
Total Alkalinity (mg/L as CaCO3)
Free CO2 (mg/L)
Total Alkalinity Reduction (mg/L as CaCO3)
Acid Required (meq/L)
93% Sulfuric Acid Required (mg/L)
93% Sulfuric Acid Required (lb/1,000 gal)
Raw Water
7.5
70
4.2
After pH
Adjustment
6.4
40
31
30
0.6
31
0.26
of the source water pH to 6.4 in mid-December 2004, increases in sulfate concentration averaged 34
mg/L. This amount closely matched the 31 mg/L derived from the actual acid consumption and the
theoretical calculation shown in Table 4-7.
Figure 4-12 shows the silica concentrations (as SiO2) over time across the treatment train. Silica
concentrations in the source water ranged from 18.7 to 21.4 mg/L, which were similar to those in samples
collected at the AP location following chlorination and pH adjustment. Elevated silica concentrations as
high as 61.8 mg/L were measured in the treated water following the lead and lag vessels. The increase in
silica concentration was attributed to the G2 media which, as discussed in Section 4.2, is a silica based
material. The leaching of silica from both vessels leveled off after about 2,000 BVs, but continued
throughout the remainder of the study period with increase in concentrations ranging from 1.6 to 3.0 mg/L
after the lead vessel and from 3.7 to 6.2 mg/L after the lag vessel.
Silica Results for Bow, NH
-Inlet
After Prechlorination
-Vessel A
-Vessel B
10/10/04 10/31/04 11/21/04 12/12/04 1/2/05 1/23/05 2/13/05
3/6/05 3/27/05 4/17/05
Figure 4-12. Silica Concentrations Over Time
32
-------
Total hardness results ranged from 81.5 to 166.6 mg/L as CaCO3. Hardness, which was predominantly
calcium hardness, was consistent across the treatment train and did not appear to be affected by any of the
steps involved in the treatment process. Fluoride concentrations ranged from 0.3 to 1.1 mg/L.
Orthophosphate was below the detection limit in all samples collected during this period. Nitrate (as N)
ranged from 0.1 to 1.4 mg/L.
Free and total chlorine was measured at the AP, TA, and TB sampling locations. Typically, free chlorine
levels were measured at 0.1 to 0.7 mg/L at the AP location, with total chlorine levels ranging from 0.1 to
0.5 mg/L. Residual chlorine levels measured at the TA and TB locations were similar to those measured
at the AP location, indicating little or no chlorine consumption by the G2 media.
DO levels ranged from 2.9 to 6.8 mg/L across the treatment train and were consistent at each location.
ORP readings at the IN location varied from 195 to 498 mV and averaged 233 mV. After chlorination,
the ORP readings increased significantly, ranging from 173 to 610 mV and averaging 435, 471, and 484
mV, respectively, at the AP, TA, and TB locations.
4.5.2 Backwash Water Sampling. Backwash water was sampled on January 11 and April 12,
2005. Samples were collected from the sample port located in the backwash effluent discharge line from
each vessel. Unfiltered samples were analyzed for pH, turbidity, and TDS. Filtered samples (using 0.45-
|om disc filters) were analyzed for soluble As, Fe, and Mn. Soluble iron was below the detection limit in
each of the samples collected; soluble manganese concentrations also were low, comparable to the levels
observed in the raw water. Soluble As concentrations in the Vessel A backwash water were 40.3 to 42.8
Hg/L, similar to the levels measured in the source water. Soluble As concentrations in the Vessel B
backwash water were lower, ranging from 11.4 to 26.1 |o,g/L. Because finished water was used for
backwash, these concentrations suggest that some arsenic might have been desorbed from the media
during backwashing. The analytical results from the two backwash water sampling events are
summarized in Table 4-8. Note that future backwash samples collected during the remainder of this
demonstration study will include collection and analysis of total suspended solids (TSS) and total As, Fe,
and Mn. These parameters were not included in the sampling performed during the first six months of
system operation.
Table 4-8. Backwash Water Sampling Results
Vessel
A
Vessel
B
Date
01/11/05
04/12/05
01/11/05
04/12/05
pH
S.U.
6.9
6.2
6.7
6.6
Turbidity
NTU
140
200
390
120
TDS
mg/L
38.0
244
72.0
240
Soluble
As(a)
Hg/L
40.3
42.8
11.4
26.1
Soluble
Fe(a)
Hg/L
<25
<25
<25
<25
Soluble
Mn(a)
HS/L
0.8
2.0
2.3
0.7
(a) Filtered (0.45 |am) samples.
4.5.3 Distribution System Water Sampling. Distribution system samples were collected to
investigate if the water treated by the arsenic removal system would impact the lead and copper level and
water chemistry in the distribution system. Prior to the installation and operation of the system, baseline
distribution system water samples were collected at three homes on July 21, August 5, August 18, and
September 8, 2004. Following the installation of the system, distribution system water sampling
continued on a monthly basis at the same three locations. The samples were analyzed for pH, alkalinity,
33
-------
arsenic, iron, manganese, lead, and copper. The results of the distribution system sampling are
summarized in Table 4-9.
As expected, prior to the installation of the arsenic removal system, arsenic concentrations in the
distribution system were similar to those measured in the raw water, ranging from 36.9 to 52.3 |o,g/L.
After the treatment system was installed and put into service, arsenic concentrations in the distribution
system decreased significantly and closely mirrored those measured after the treatment system at
sampling location TB, ranging from 3.9 to 12.4 |o,g/L.
Iron concentrations were similar to those observed in the raw water, and were typically below the
detection limit of 25 |og/L. The iron concentration in the sample collected on January 12, 2005 at the DS1
location was high; it was not clear why this concentration was significantly higher than the other relevant
data points.
Manganese concentrations in the distribution system generally followed those measured after the lag
vessel with the highest concentrations (i.e., 16.0 |o,g/L) observed soon after the system was installed.
Sampling location DS2 did not show as significant an increase in the manganese levels. The manganese
concentrations declined steadily to levels only slightly higher than those observed during the baseline
sampling after about three months of system operation (or about 2,500 BVs).
The pH values measured during the baseline sampling ranged from 7.2 to 7.8. After the system was
installed, the pH values ranged from 6.6 to 8.1. The pH values across all three locations were high during
the sampling event on December 8, 2004. During the next sampling event on January 12, 2005, however,
the pH values were significantly lower, ranging from 6.6 to 6.8. This swing in pH was likely caused by
difficulties encountered with adjustments to the rate of caustic addition as described under Operator Skill
Requirements in Section 4.4.4. The lower pH values appeared to have had a significant impact on the
lead and copper levels in the distribution system. Prior to the January 2005 sampling event, the lead and
copper levels measured at the three sampling locations ranged from 1.4 to 2.4 |o,g/L for lead and from 35.4
to 147.0 ng/L for copper, which were consistent with the baseline values of 0.8 to 4.6 |o,g/L for lead and
62.1 to 240.1 |og/L for copper. With the pH drop in January 2005, the lead concentration increased to 9.9
Hg/L at the DS3 location; and copper levels increased across all three sampling locations, with the most
noticeable increase exceeding the action level of 1.3 mg/L at the DS3 location. During the subsequent
monthly sampling events, the pH values were better controlled; however, the lead and copper levels
continued to be higher than those observed before the pH drop in January.
For the most part, alkalinity levels were consistent throughout the baseline sampling and five of the six
monthly sampling events, ranging from 54 to 80 mg/L (as CaCO3). In January 2005, alkalinity values
were lower (i.e., 43 to 55 mg/L), consistent with the low pH values measured during this sampling event.
4.6 System Costs
The cost-effectiveness of the system is evaluated based on the dollar cost per 1,000 gal of water treated.
This includes the tracking of capital costs such as equipment, engineering, and installation costs and
O&M costs such as media replacement and disposal, chemical supply, electrical power use, and labor.
4.6.1 Capital Costs. The capital investment costs for equipment, site engineering, and installation
were $154,700 (see Table 4-10). The equipment costs were $102,600 (or 66% of the total capital
investment), which included $76,100 for the adsorption system (vessels and piping), $6,000 for the G2
media (i.e., $35/ft3 or $0.75/lb to fill two vessels), $3,900 for the backwash booster pump, and vendor's
labor and travel for the system shakedown and startup.
34
-------
Table 4-9. Distribution System Sampling Results
No. of
Sampling
Events
BLl
BL2
BL3
BL4
1
2
3
4
5
6
Sampling
Location
Sampling Date
07/21/04
08/05/04
08/18/04
09/08/04
11/03/04<")
12/08/04
01/12/05
02/09/05
03/09/05
04/20/05
'x*
&
|
H
Eb
•8
8.5
7.5
7.0
9.3
8.8
10.0
9.0
5.5
7.0
7.4
"a
7.4
7.2
7.7
7.8
7.5
8.1
6.8
7.5
7.6
7.3
•a
a
3
•^
80
68
60
64
62
61
44
54
70
72
D
X
cs
"o
44.1
52.3
36.9
51.0
11.2
5.6
3.9
4.4
7.1
7.7
SI
&
cs
"o
<25
<25
28
<25
<25
<25
174/257
<25
<25
<25
B
CS
"o
1.1
5.0
0.7
0.9
11.7
7.5
7.7
2.6
2.1
2.6
.Q
—
CS
"o
2.5
4.6
1.9
0.8
1.5
0.9
3.1
5.9
1.6
3.7
5
cs
"o
93.7
88.7
122.2
92.7
107.0
35.4
375 O/
464.0
379.0
56.0
262.1
'x*
&
|
H
Eb
S
7.8
8.0
7.5
7.8
8.8
7.8
7.7
7.8
7.7
7.7
"a
7.4
7.2
7.6
7.8
7.6
8.1
6.8
7.4
7.4
7.1
•a
a
^
68
66
60
64
66
61
55
61
57
67
D
X
cs
"o
41.1
45.8
41.3
49.1
8.5
12.4
5.7
4.8
5.3
4.2
S2
&
cs
"o
<25
<25
38
<25
<25
<25
<25
28
<25
<25
B
CS
"o
0.5
0.6
1.8
0.5
3.0
2.4
3.5
2.7
2.2
2.4
.Q
—
CS
"o
1.1
2.7
3.8
0.8
0.8
1.6
3.7
1.9
4.2
3.6
5
cs
"o
163.5
240.1
62.8
75.9
94.9
111.0
747 O/
844.0
731.0
882.0
739.1
'x*
&
|
H
Eb
S
6.3
7.0
7.0
8.2
8.3
8.8
10.7
8.3
9.0
8.3
"a
7.4
7.3
7.6
7.7
7.8
8.0
6.6
7 2
7.4
7.1
•a
a
3
•^
60
60
60
64
62
61
43
64
71
64
D
X
cs
"o
41.4
48.2
39.5
50.0
9.3
9.6
5.3
5.1
7.3
9.9
S3
(2
cs
"o
<25
<25
34
<25
<25
<25
30
<25
<25
26
B
CS
"o
0.4
1.6
0.5
0.6
16.0
4.0
10.4
6.3
2.1
3.0
.Q
—
CS
"o
2.0
2.2
2.4
1.0
1.4
2.4
9.9
6.7
5.0
5.0
5
cs
"o
149.8
62.1
129.1
128.7
41.0
147.0
1 345/
1,378
814.0
461.0
429.8
BL = baseline sampling
DS = distribution sampling
(a) Sample at DS2 was taken on November 8, 2004
(/) indicates laboratory re-run data with original result/re-run result
Lead action level = 15 ug/L; copper action level = 1.3 mg/L
The unit for analytical parameters is ug/L, except for pH (standard unit) and alkalinity (mg/L as CaCO3)
-------
Table 4-10. Capital Investment for the G2 Media Treatment System
Description
Quantity
Cost
% of Capital
Investment Cost
Equipment Costs
Adsorption System
G2 Media
Backwash Booster Pump
Field Services (Vendor Labor and Travel)
Equipment Total
1 unit
170 ft3
1
-
-
$76,100
$6,000
$3,900
$16,600
$102,600
-
-
-
-
66%
Engineering Costs
Vendor Labor
Engineering Total
-
-
$12,500
$12,500
-
8%
Installation Costs
Subcontractor
Vendor Labor
Vendor Travel
Installation Total
Total Capital Investment
-
-
-
-
-
$32,500
$3,550
$3,550
$39,600
$154,700
-
-
-
26%
100%
The engineering costs included the costs for the preparation of the system layout and footprint, design of
the piping connections up to the distribution tie-in points, design of the electrical connections, and
assembling and submission of the engineering plans for the permit application (Section 4.3.1). The
engineering costs were $12,500, which was 8% of the total capital investment.
The installation costs included the costs for the equipment and labor to unload and install the adsorption
unit, perform the piping tie-ins and electrical work, and load and condition the media (Section 4.3.3). The
installation was conducted by Lewis Engineering and C&C Water Services subcontracted to ADI. The
installation costs were $39,600, or 26% of the total capital investment.
C&C Water Services constructed an aboveground addition to the existing underground pump house
structure to house the G2 media treatment system (Section 4.3.2). The cost of building the addition was
approximately $25,000, including placement of a steel support on top of the existing concrete structure
and construction of a wooden frame building on this steel support.
The total capital cost of $154,700 and equipment cost of $102,600 were converted to a unit cost of
$0.28/1,000 gallon and $0.19/1,000 gallon, respectively, using a capital recovery factor (CRF) of 0.06722
based on a 3% interest rate and a 20-year return period (Chen et al., 2004). These calculations assumed
that the system operated 24 hr per day, 7 days per week at the original system design flowrate of 70 gpm.
The system operated an average of 9.3 hr per day (see Table 4-4), producing 3,858,000 gal of water
during the 6-month period, so the total unit cost and equipment-only unit cost were increased to
$1.32/1,000 gallons and $0.83/1,000 gallons, respectively, at this reduced rate of usage. Using the
system's actual capacity of 40 gpm (57,600 gpd), the capital cost was $3,868/gpm ($2.68/gpd) and
equipment-only cost was $2,565/gpm ($1.78/gpd). These calculations did not include the cost of the
building construction.
4.6.2 Operation and Maintenance Costs. O&M costs for the G2 media treatment system include
only incremental costs associated with the adsorption system, such as media replacement and disposal,
chemical supply, electricity, and labor. These costs are summarized in Table 4-11. Although media
replacement and disposal did not take place during the first six months of operation, the cost to change
out the lead vessel was estimated to be $9,396 based on information provided by the vendor and a local
36
-------
Table 4-11. O&M Costs for the G2 Media Treatment System
Cost Category
Volume processed (kgal)
Value
3,858
Assumptions
Through April 24, 2005
Media Replacement and Disposal
Media cost ($/ft3)
Total media volume (ft3)
Media replacement cost ($)
Freight ($)
Labor cost ($)
Waste Analysis, TCLP ($)
Media disposal fee ($)
Subtotal
Media replacement and disposal cost
($71,000 gal)
40
85
3,400
580
4,226
300
890
$9,396
See Figure 4-13
Vendor quote
Both vessels
Vendor quote
-
Vendor quote
-
Vendor quote
Vendor quote
Based upon media run length at 10-|j,g/L
arsenic breakthrough
Chemical Usage
Acid unit price ($/lb)
Acid consumption rate (lb/ 1,000 gal)
Acid cost ($71,000 gal)
Caustic unit price ($/lb)
Caustic consumption rate
(lb/1,000 gal)
Caustic cost ($71,000 gal)
Total chemical cost ($71,000 gal)
0.40
0.24
0.10
0.63
0.45
0.28
0.38
200 lb container at $80
925 lb used to treat 3,858 kgal
-
1 60 lb container at $100
1740 lb used to treat 3,858 kgal
-
Cost for acid and caustic addition, no
additional costs for chlorination
Electricity
Electricity cost ($71,000 gal)
$0.001
Electrical costs assumed negligible
Labor
Average weekly labor (hrs)
Labor cost ($71,000 gal)
Total O&M cost ($71,000 gal)
2.33
$0.34
See Figure 4-13
20 min/day
Labor rate = $20/hr
Based upon media run length at 10-|j,g/L
arsenic breakthrough
subcontractor. This cost was used to estimate the media replacement cost per 1,000 gal of water treated
as a function of the projected media run length to the lO-jog/L arsenic breakthrough (Figure 4-13).
With a system that operates in series, the media in the lead vessel is ideally replaced when the arsenic
concentration in the treated water following the lead vessel equals the incoming raw water concentration
and before the arsenic concentration following the lag vessel reaches the 10-|o,g/L target value. Once the
lead vessel is rebedded, the lead and lag vessels are switched, so that the lag vessel is placed in the lead
position and the former lead vessel, now with new media, is placed in the lag position. This method
maximizes the usage of the media so that the entire capacity for arsenic removal is exhausted before the
media is replaced.
Chemical costs included sodium hypochlorite for chlorination and sulfuric acid and NaOH for pH
adjustment. Sodium hypochorite was in use prior to the installation of the G2 media treatment system for
the purpose of maintaining chlorine residual in the distribution system. The treatment system did not
37
-------
o
o
$16.00
$14.00
$12.00
$10.00
$8.00
$6.00
$4.00
$2.00
$0.00
—O&M Cost (including Media
Replacement)
— Media Replacement Cost
1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000
Media Working Capacity, Bed Volumes
Figure 4-13. Media Replacement and O&M Costs
change the use rate of the sodium hypochlorite solution. Therefore, the chemical cost related to the use of
sodium hypochlorite was unchanged. During the first six months of system operation, 5 containers (15-
gal, 200 Ib per container) of 93% sulfuric acid and 11 containers (15-gal, 160 Ib per container) of 25%
NaOH were consumed for pH adjustment. Based on the price per drum of approximately $80 and $100
for acid and caustic, respectively, the total chemical cost for this period was about $1,500 or $0.38/1,000
gallons.
The electrical usage rate for the pump station averaged 131 kWh per day during the six-month study
period. Comparison of electrical bills prior to system installation and since startup indicated that the
treatment system did not cause a noticeable increase in power consumption. Therefore, electrical costs
associated with operation of the G2 media treatment system were negligible.
The routine, non-demonstration-related labor activities consumed about 20 minutes per day, as noted in
Section 4.4.4. Therefore, the estimated labor cost is $0.34/1,000 gal of water treated.
38
-------
5.0 REFERENCES
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 Bow, New Hampshire. Prepared under Contract No. 68-C-00-185, Task
Order No. 0019 for U.S. EPA NRMRL. October 6.
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. EPA NRMRL, 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.
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. Fed. 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.
39
-------
APPENDIX A
OPERATIONAL DATA
-------
EPA Arsenic Demonstration at WRWC in Bow, NH- Summary of Daily System Operational Data (Page 1 of 5)
Week No.
1
2
3
4
5
6
Date
10/11/2004
10/12/2004
10/13/2004
10/14/2004
10/15/2004
10/16/2004
10/17/2004
10/18/2004
10/19/2004
10/20/2004
10/21/2004
10/22/2004
10/23/2004
1 0/24/2004
10/25/2004
10/26/2004
10/27/2004
10/28/2004
10/29/2004
10/30/2004
10/31/2004
11/1/2004
11/2/2004
11/3/2004
11/4/2004
11/5/2004
11/6/2004
11/7/2004
11/8/2004
11/9/2004
11/10/2004
11/11/2004
11/12/2004
11/13/2004
11/14/2004
11/15/2004
11/16/2004
11/17/2004
11/18/2004
11/19/2004
11/20/2004
11/21/2004
Avg
Operation
Hours
hr
NA
6.7
NA
NA
NA
NA
NA
NA
7.3
8.4
6.6
8.9
7.8
7.2
8.8
6.8
8.4
7.5
7.6
9.6
9.7
7.9
9.2
6.9
8.6
8.8
8.1
8.8
9.2
7.7
7.2
7.7
9.8
7.7
8.3
8.9
8.2
7.9
7.5
8.6
9.7
8.4
Cumulative
Operation
Hours
hr
NA
6.7
NA
NA
NA
NA
NA
NA
14.0
22.4
29.0
37.9
45.7
52.9
61.7
68.5
76.9
84.4
92.0
101.6
111.3
119.2
128.4
135.3
143.9
152.7
160.8
169.6
178.8
186.5
193.7
201.4
211.2
218.9
227.2
236.1
244.3
252.2
259.7
268.3
278.0
286.4
Oulet Magnetic Meter
Outlet
Flowrate
gpm
NM
NM
36
NM
NM
NM
NM
NM
38.6
26.9
30.6
39.0
44.0
47.0
48.0
38.0
45.0
46.0
48.0
49.0
44.0
41.7
44.0
44.0
43.0
43.3
41.0
43.0
45.0
42.0
43.0
45.0
36.0
42.0
41.0
48.0
40.0
42.0
43.0
41.0
44.0
40.0
Outlet
Totalizer
gal
NM
NM
537,160
NM
NM
NM
NM
NM
643,625
664,300
680,661
702,593
721 ,837
739,366
760,847
777,478
797,624
816,002
834,796
858,346
880,781
899,790
921 ,975
938,108
957,946
978,591
997,718
1,017,767
1 ,038,441
1,056,213
1 ,073,299
1 ,091 ,607
1,114,759
1,132,453
1,151,444
1,171,547
1,198,461
1 ,208,577
1,226,155
1 ,246,352
1 ,268,470
1 ,286,856
Daily
Flow
Totalizer
gal
NA
NA
NA
NA
NA
NA
NA
NA
106,465
20,675
16,361
21 ,932
19,244
17,529
21 ,481
16,631
20,146
18,378
18,794
23,550
22,435
19,009
22,185
16,133
19,838
20,645
19,127
20,049
20,674
17,772
17,086
18,308
23,152
17,694
18,991
20,103
26,914
10,116
17,578
20,197
22,118
18,386
Cumulative
Volume
Treated
gal
NA
NA
NA
NA
NA
NA
NA
NA
106,465
127,140
143,501
165,433
184,677
202,206
223,687
240,318
260,464
278,842
297,636
321,186
343,621
362,630
384,815
400,948
420,786
441 ,431
460,558
480,607
501 ,281
519,053
536,139
554,447
577,599
595,293
614,284
634,387
661,301
671,417
688,995
709,192
731,310
749,696
Cumulative
Bed
Volumes
Treated
NA
NA
NA
NA
NA
NA
NA
NA
167
200
226
260
290
318
352
378
410
439
468
505
540
570
605
631
662
694
724
756
788
816
843
872
908
936
966
998
1040
1056
1084
1115
1150
1179
Vessel A
Inlet
Pressure
psi
NM
0
3
NM
NM
NM
NM
NM
2.0
1.0
1.0
2.0
2.0
3.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
5.0
8.0
8.0
8.0
8.0
8.0
8.0
10.0
10.0
10.0
10.0
6.0
8.0
8.0
9.0
12.0
10.0
12.0
10.0
10.0
10.0
Outlet
Pressure
psi
NM
3
5
NM
NM
NM
NM
NM
3.0
2.0
3.0
2.0
2.0
4.0
3.0
3.0
4.0
4.0
3.0
3.0
3.0
5.0
10.0
10.0
10.0
10.0
8.0
10.0
10.0
11.0
10.0
10.0
8.0
10.0
9.0
10.0
12.0
12.0
12.0
12.0
11.0
11.0
Ap
psi
NA
NA
NA
NA
NA
NA
NA
NA
1.0
1.0
2.0
0.0
0.0
1.0
1.0
1.0
2.0
2.0
1.0
1.0
1.0
0.0
2.0
2.0
2.0
2.0
0.0
2.0
0.0
1.0
0.0
0.0
2.0
2.0
1.0
1.0
0.0
2.0
0.0
2.0
1.0
1.0
Vessel B
Inlet
Pressure
psi
NM
0
2
NM
NM
NM
NM
NM
1.0
0.5
1.0
1.0
1.0
2.0
2.0
1.0
2.0
2.0
2.0
1.0
1.0
4.0
8.0
6.0
6.0
6.0
6.0
6.0
8.0
8.0
9.0
8.0
4.0
8.0
5.0
8.0
11.0
9.0
11.0
9.0
8.0
10.0
Oulet
Pressure
psi
NM
3
5
NM
NM
NM
NM
NM
2.0
2.0
2.0
2.0
2.0
3.0
3.0
2.0
3.0
3.0
3.0
2.0
2.0
5.0
10.0
8.0
8.0
8.0
8.0
8.0
10.0
10.0
10.0
10.0
8.0
10.0
8.0
9.0
12.0
11.0
12.0
11.0
10.0
11.0
Ap
psi
NA
NA
NA
NA
NA
NA
NA
NA
1.0
1.5
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
1.0
2.0
4.0
2.0
3.0
1.0
1.0
2.0
1.0
2.0
2.0
1.0
-------
EPA Arsenic Demonstration at WRWC in Bow, NH- Summary of Daily System Operational Data (Page 2 of 5)
Week No.
7
8
9
10
11
12
Date
11/22/2004
11/23/2004
11/24/2004
11/25/2004
11/26/2004
11/27/2004
11/28/2004
11/29/2004
11/30/2004
12/1/2004
1 2/2/2004
1 2/3/2004
1 2/4/2004
1 2/5/2004
1 2/6/2004
1 2/7/2004
12/8/2004
12/9/2004
12/10/2004
12/11/2004
12/12/2004
12/13/2004
12/14/2004
12/15/2004
12/16/2004
12/17/2004
12/18/2004
12/19/2004
12/20/2004
12/21/2004
12/22/2004
12/23/2004
12/24/2004
12/25/2004
12/26/2004
12/27/2004
12/28/2004
12/29/2004
12/30/2004
12/31/2004
1/1/2005
1/2/2005
Avg
Operation
Hours
hr
8.6
7.3
9.7
8.2
8.8
8.4
11.0
7.6
8.5
7.1
8.1
9.1
7.4
9.2
7.3
7.6
7.7
8.0
8.2
8.4
10.2
7.2
9.4
6.5
7.0
9.2
8.1
9.4
9.1
7.2
8.7
NA
20.8
9.9
10.6
9.7
8.8
9.8
10.1
11.7
7.4
23.5
Cumulative
Operation
Hours
hr
295.0
302.3
312.0
320.2
329.0
337.4
348.4
356.0
364.5
371.6
379.7
388.8
396.2
405.4
412.7
420.3
428.0
436.0
444.2
452.6
462.8
470.0
479.4
485.9
492.9
502.1
510.2
519.6
528.7
535.9
544.6
NA
565.4
575.3
585.9
595.6
604.4
614.2
624.3
636.0
643.4
666.9
Oulet Magnetic Meter
Outlet
Flowrate
gpm
39.3
40.3
43.3
41.7
41.3
40.3
39.4
40.1
46.7
41.5
41.6
38.2
41.5
42.5
42.3
41.1
43.8
43.4
43.7
42.6
36.8
42.9
45.5
41.7
43.4
41.6
41.3
38.0
41.6
42.3
41.4
NM
41.8
38.7
40.6
42.1
39.5
40.8
36.5
35.4
38.5
31.5
Outlet
Totalizer
gal
1 ,306,700
1 ,323,674
1 ,345,91 1
1 ,364,685
1 ,384,761
1,403,810
1 ,427,681
1 ,444,834
1 ,463,974
1 ,480,492
1 ,499,233
1 ,520,747
1 ,537,957
1 ,558,903
1,575,151
1 ,592,399
1,610,551
1 ,628,928
1 ,648,334
1 ,667,441
1 ,690,927
1 ,706,789
1 ,728,436
1 ,744,098
1 ,760,533
1,782,219
1 ,800,894
1 ,822,426
1 ,842,688
1 ,854,450
1 ,878,671
NM
1 ,924,958
1 ,946,344
1 ,969,074
1 ,988,059
2,008,591
2,030,335
2,052,360
2,077,382
2,093,961
2,134,111
Daily
Flow
Totalizer
gal
19,844
16,974
22,237
18,774
20,076
19,049
23,871
17,153
19,140
16,518
18,741
21,514
17,210
20,946
16,248
17,248
18,152
18,377
19,406
19,107
23,486
15,862
21 ,647
15,662
16,435
21 ,686
18,675
21 ,532
20,262
1 1 ,762
24,221
NA
NA
21 ,386
22,730
18,985
20,532
21 ,744
22,025
25,022
16,579
40,150
Cumulative
Volume
Treated
gal
769,540
786,514
808,751
827,525
847,601
866,650
890,521
907,674
926,814
943,332
962,073
983,587
1 ,000,797
1 ,021 ,743
1 ,037,991
1 ,055,239
1 ,073,391
1 ,091 ,768
1,111,174
1,130,281
1,153,767
1,169,629
1,191,276
1 ,206,938
1 ,223,373
1 ,245,059
1 ,263,734
1 ,285,266
1 ,305,528
1,317,290
1,341,511
NA
NA
1 ,362,897
1 ,385,627
1,404,612
1,425,144
1 ,446,888
1,468,913
1 ,493,935
1,510,514
1 ,550,664
Cumulative
Bed
Volumes
Treated
1210
1237
1272
1302
1333
1363
1401
1428
1458
1484
1513
1547
1574
1607
1633
1660
1688
1717
1748
1778
1815
1840
1874
1898
1924
1958
1988
2021
2053
2072
2110
NA
NA
2144
2179
2209
2241
2276
2310
2350
2376
2439
Vessel A
Inlet
Pressure
psi
10.0
10.0
11.0
11.0
12.0
10.0
10.0
10.0
12.0
12.0
12.0
9.0
10.0
9.0
12.0
12.0
13.0
13.0
11.0
12.0
9.0
13.0
10.0
9.0
10.0
8.0
9.0
7.0
7.0
10.0
10.0
NM
10.0
10.0
10.0
9.0
9.0
8.0
7.0
7.0
9.0
6.0
Outlet
Pressure
psi
11.0
11.0
12.0
12.0
12.0
11.0
11.0
11.0
13.0
13.0
13.0
9.0
10.0
9.0
12.0
12.0
13.0
13.0
12.0
12.0
9.0
12.0
10.0
9.0
10.0
8.0
8.0
7.0
8.0
10.0
10.0
NM
10.0
9.0
9.0
9.0
9.0
7.0
7.0
7.0
9.0
4.0
Ap
psi
1.0
1.0
1.0
1.0
0.0
1.0
1.0
1.0
1.0
1.0
1.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.0
0.0
1.0
0.0
0.0
0.0
0.0
1.0
0.0
1.0
0.0
0.0
NA
0.0
1.0
1.0
0.0
0.0
1.0
0.0
0.0
0.0
2.0
Vessel B
Inlet
Pressure
psi
8.0
9.0
10.0
9.0
10.0
10.0
9.0
10.0
10.0
10.0
10.0
7.0
8.0
7.0
10.0
9.0
11.0
11.0
9.0
13.0
7.0
12.0
7.0
7.0
7.0
6.0
6.0
5.0
6.0
7.0
7.0
NM
7.0
7.0
7.0
7.0
7.0
6.0
5.0
5.0
7.0
3.0
Oulet
Pressure
psi
10.0
11.0
12.0
11.0
11.0
11.0
10.0
12.0
12.0
12.0
12.0
9.0
10.0
8.0
12.0
12.0
12.0
12.0
11.0
12.0
9.0
12.0
9.0
8.0
9.0
7.0
7.0
7.0
7.0
9.0
9.0
NM
9.0
9.0
8.0
8.0
8.0
8.0
7.0
6.0
8.0
6.0
Ap
psi
2.0
2.0
2.0
2.0
1.0
1.0
1.0
2.0
2.0
2.0
2.0
2.0
2.0
1.0
2.0
3.0
1.0
1.0
2.0
1.0
2.0
0.0
2.0
1.0
2.0
1.0
1.0
2.0
1.0
2.0
2.0
NA
2.0
2.0
1.0
1.0
1.0
2.0
2.0
1.0
1.0
3.0
>
-------
EPA Arsenic Demonstration at WRWC in Bow, NH- Summary of Daily System Operational Data (Page 3 of 5)
Week No.
13
14
15
16
17
18
Date
1/3/2005
1/4/2005
1/5/2005
1/6/2005
1/7/2005
1/8/2005
1/9/2005
1/10/2005
1/11/2005
1/12/2005
1/13/2005
1/14/2005
1/15/2005
1/16/2005
1/17/2005
1/18/2005
1/19/2005
1/20/2005
1/21/2005
1/22/2005
1/23/2005
1/24/2005
1/25/2005
1/26/2005
1/27/2005
1/28/2005
1/29/2005
1/30/2005
1/31/2005
2/1/2005
2/2/2005
2/3/2005
2/4/2005
2/5/2005
2/6/2005
2/7/2005
2/8/2005
2/9/2005
2/10/2005
2/11/2005
2/12/2005
2/13/2005
Avg
Operation
Hours
hr
7.3
8.5
8.1
10.5
8.9
8.5
9.6
9.5
12.4
6.6
9.4
7.8
9.8
10.3
9.5
8.5
7.9
8.6
9.1
9.4
9.6
9.1
8.1
8.0
8.4
10.1
8.0
12.3
8.0
7.9
8.3
8.3
8.7
9.8
11.3
7.5
7.9
8.4
9.1
8.9
9.9
10.0
Cumulative
Operation
Hours
hr
674.2
682.7
690.8
701.3
710.2
718.7
728.3
737.8
750.2
756.8
766.2
774.0
783.8
794.1
803.6
812.1
820.0
828.6
837.7
847.1
856.7
865.8
873.9
881.9
890.3
900.4
908.4
920.7
928.7
936.6
944.9
953.2
961.9
971.7
983.0
990.5
998.4
1006.8
1015.9
1024.8
1034.7
1044.7
Oulet Magnetic Meter
Outlet
Flowrate
gpm
40.3
41.6
43.0
38.2
40.6
40.1
44.3
40.3
31.5
43.2
40.3
40.7
40.0
40.8
39.9
43.7
41.5
40.3
41.1
40.4
42.7
41.3
40.1
42.2
44.3
38.2
37.0
34.0
39.6
42.4
37.3
45.9
39.5
45.7
36.8
40.7
41.1
47.2
43.1
39.7
33.6
38.8
Outlet
Totalizer
gal
2,149,653
2,168,274
2,186,659
2,210,604
2,229,746
2,248,542
2,269,572
2,290,483
2,317,137
2,331 ,891
2,352,893
2,369,333
2,391,115
2,413,979
2,434,854
2,452,751
2,470,822
2,490,330
2,510,687
2,531 ,399
2,552,097
2,571 ,909
2,590,546
2,608,795
2,627,629
2,650,511
2,668,851
2,695,129
2,711,222
2,729,013
2,747,686
2,766,522
2,786,021
2,807,547
2,831 ,725
2,848,555
2,866,591
2,885,410
2,906,231
2,925,923
2,948,119
2,969,745
Daily
Flow
Totalizer
gal
15,542
18,621
18,385
23,945
19,142
18,796
21 ,030
20,91 1
26,654
14,754
21 ,002
16,440
21 ,782
22,864
20,875
17,897
18,071
19,508
20,357
20,712
20,698
19,812
18,637
18,249
18,834
22,882
18,340
26,278
16,093
17,791
18,673
18,836
19,499
21 ,526
24,178
16,830
18,036
18,819
20,821
19,692
22,196
21 ,626
Cumulative
Volume
Treated
gal
1 ,566,206
1 ,584,827
1,603,212
1,627,157
1 ,646,299
1 ,665,095
1,686,125
1 ,707,036
1 ,733,690
1 ,748,444
1 ,769,446
1 ,785,886
1 ,807,668
1 ,830,532
1 ,851 ,407
1 ,869,304
1 ,887,375
1 ,906,883
1 ,927,240
1 ,947,952
1 ,968,650
1 ,988,462
2,007,099
2,025,348
2,044,182
2,067,064
2,085,404
2,111,682
2,127,775
2,145,566
2,164,239
2,183,075
2,202,574
2,224,100
2,248,278
2,265,108
2,283,144
2,301 ,963
2,322,784
2,342,476
2,364,672
2,386,298
Cumulative
Bed
Volumes
Treated
2463
2493
2522
2559
2589
2619
2652
2685
2727
2750
2783
2809
2843
2879
2912
2940
2969
2999
3031
3064
3096
3127
3157
3186
3215
3251
3280
3321
3347
3375
3404
3434
3464
3498
3536
3563
3591
3621
3653
3684
3719
3753
Vessel A
Inlet
Pressure
psi
10.0
11.0
11.0
7.0
9.0
10.0
10.0
9.0
7.0
15.0
12.0
15.0
14.0
12.0
11.0
15.0
14.0
14.0
12.0
12.0
13.0
14.0
15.0
15.0
16.0
11.0
11.0
8.0
16.0
15.0
16.0
16.0
16.0
15.0
10.0
16.0
16.0
16.0
13.0
13.0
11.0
13.0
Outlet
Pressure
psi
10.0
10.0
11.0
7.0
8.0
10.0
10.0
8.0
8.0
15.0
13.0
15.0
15.0
13.0
13.0
16.0
15.0
15.0
13.0
13.0
13.0
15.0
16.0
16.0
16.0
12.0
12.0
8.0
16.0
16.0
16.0
16.0
16.0
15.0
10.0
16.0
16.0
16.0
13.0
13.0
12.0
13.0
Ap
psi
0.0
1.0
0.0
0.0
1.0
0.0
0.0
1.0
1.0
0.0
1.0
0.0
1.0
1.0
2.0
1.0
1.0
1.0
1.0
1.0
0.0
1.0
1.0
1.0
0.0
1.0
1.0
0.0
0.0
1.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.0
Vessel B
Inlet
Pressure
psi
7.0
8.0
8.0
5.0
7.0
7.0
7.0
7.0
6.0
13.0
11.0
13.0
12.0
11.0
10.0
13.0
12.0
12.0
10.0
10.0
11.0
12.0
14.0
14.0
14.0
9.0
10.0
6.0
14.0
14.0
14.0
14.0
14.0
13.0
8.0
14.0
14.0
14.0
10.0
11.0
9.0
11.0
Oulet
Pressure
psi
9.0
10.0
10.0
7.0
9.0
9.0
9.0
8.0
8.0
15.0
13.0
15.0
14.0
13.0
12.0
11.0
15.0
15.0
13.0
13.0
14.0
15.0
16.0
16.0
16.0
12.0
12.0
9.0
16.0
15.0
16.0
15.0
15.0
14.0
9.0
15.0
15.0
15.0
11.0
12.0
11.0
13.0
Ap
psi
2.0
2.0
2.0
2.0
2.0
2.0
2.0
1.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
3.0
3.0
3.0
3.0
3.0
3.0
2.0
2.0
2.0
3.0
2.0
3.0
2.0
1.0
2.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
2.0
2.0
>
-------
EPA Arsenic Demonstration at WRWC in Bow, NH- Summary of Daily System Operational Data (Page 4 of 5)
Week No.
19
20
21
22
23
24
Date
2/14/2005
2/15/2005
2/16/2005
2/17/2005
2/18/2005
2/19/2005
2/20/2005
2/21/2005
2/22/2005
2/23/2005
2/24/2005
2/25/2005
2/26/2005
2/27/2005
2/28/2005
3/1/2005
3/2/2005
3/3/2005
3/4/2005
3/5/2005
3/6/2005
3/7/2005
3/8/2005
3/9/2005
3/10/2005
3/11/2005
3/12/2005
3/13/2005
3/14/2005
3/15/2005
3/16/2005
3/17/2005
3/18/2005
3/19/2005
3/20/2005
3/21/2005
3/22/2005
3/23/2005
3/24/2005
3/25/2005
3/26/2005
3/27/2005
Avg
Operation
Hours
hr
8.9
7.8
8.4
8.5
9.1
11.0
11.0
8.6
9.1
10.4
9.6
10.5
12.5
11.4
9.1
10.0
10.4
8.0
11.5
11.0
13.2
10.6
13.2
14.1
14.1
14.3
11.0
11.0
8.2
9.1
8.1
8.4
8.7
9.2
10.7
8.0
8.0
9.8
7.1
9.5
9.8
13.2
Cumulative
Operation
Hours
hr
1053.6
1061.4
1069.8
1078.3
1087.4
1098.4
1109.4
1118.0
1127.1
1137.5
1147.1
1157.6
1170.1
1181.5
1190.6
1200.6
1211.0
1219.0
1230.5
1241.5
1254.7
1265.3
1278.5
1292.6
1306.7
1321.0
1332.0
1343.0
1351.2
1360.3
1368.4
1376.8
1385.5
1394.7
1405.4
1413.4
1421.4
1431.2
1438.3
1447.8
1457.6
1470.8
Oulet Magnetic Meter
Outlet
Flowrate
gpm
39.9
40.1
40.3
41.0
41.2
36.0
38.9
44.0
39.9
39.3
42.1
41.2
42.2
38.0
42.9
38.0
36.4
41.3
35.5
39.4
35.6
40.3
37.8
39.3
37.2
38.4
38.7
42.6
36.4
44.3
43.0
42.6
41.7
40.3
42.3
44.5
47.7
43.6
42.5
36.7
42.9
35.7
Outlet
Totalizer
gal
2,989,704
3,007,034
3,026,039
3,045,281
3,066,022
3,090,622
3,114,486
3,133,287
3,153,152
3,175,292
3,195,313
3,217,543
3,243,080
3,266,391
3,285,641
3,307,138
3,329,356
3,346,888
3,371,421
3,394,246
3,420,533
3,441 ,728
3,467,373
3,494,579
3,521 ,436
3,548,297
3,568,879
3,590,313
3,606,707
3,625,853
3,643,284
3,661 ,488
3,680,954
3,700,919
3,723,897
3,740,922
3,758,479
3,780,333
3,796,412
3,817,763
3,838,499
3,866,379
Daily
Flow
Totalizer
gal
19,959
17,330
19,005
19,242
20,741
24,600
23,864
18,801
19,865
22,140
20,021
22,230
25,537
23,311
19,250
21 ,497
22,218
17,532
24,533
22,825
26,287
21,195
25,645
27,206
26,857
26,861
20,582
21 ,434
16,394
19,146
17,431
18,204
19,466
19,965
22,978
17,025
17,557
21 ,854
16,079
21,351
20,736
27,880
Cumulative
Volume
Treated
gal
2,406,257
2,423,587
2,442,592
2,461 ,834
2,482,575
2,507,175
2,531 ,039
2,549,840
2,569,705
2,591 ,845
2,61 1 ,866
2,634,096
2,659,633
2,682,944
2,702,194
2,723,691
2,745,909
2,763,441
2,787,974
2,810,799
2,837,086
2,858,281
2,883,926
2,911,132
2,937,989
2,964,850
2,985,432
3,006,866
3,023,260
3,042,406
3,059,837
3,078,041
3,097,507
3,117,472
3,140,450
3,157,475
3,175,032
3,196,886
3,212,965
3,234,316
3,255,052
3,282,932
Cumulative
Bed
Volumes
Treated
3785
3812
3842
3872
3905
3943
3981
4010
4042
4077
4108
4143
4183
4220
4250
4284
4319
4346
4385
4421
4462
4496
4536
4579
4621
4663
4696
4729
4755
4785
4813
4841
4872
4903
4939
4966
4994
5028
5053
5087
5120
5163
Vessel A
Inlet
Pressure
psi
13.0
10.0
10.0
10.0
9.0
7.0
7.0
9.0
20.0
19.0
19.0
21.0
17.0
17.0
20.0
16.0
16.0
20.0
15.0
17.0
15.0
19.0
17.0
17.0
25.0
22.0
27.0
27.0
NA
20.0
22.0
22.0
17.0
15.0
12.0
21.0
22.0
15.0
16.0
13.0
15.0
10.0
Outlet
Pressure
psi
13.0
9.0
9.0
9.0
8.0
7.0
7.0
8.0
21.0
19.0
19.0
22.0
18.0
17.0
20.0
16.0
16.0
20.0
15.0
18.0
16.0
19.0
18.0
18.0
25.0
23.0
28.0
28.0
27.0
21.0
22.0
23.0
17.0
16.0
13.0
22.0
27.0
15.0
16.0
13.0
15.0
9.0
Ap
psi
0.0
1.0
1.0
1.0
1.0
0.0
0.0
1.0
1.0
0.0
0.0
1.0
1.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
1.0
0.0
1.0
1.0
0.0
1.0
1.0
1.0
NA
1.0
0.0
1.0
0.0
1.0
1.0
1.0
5.0
0.0
0.0
0.0
0.0
1.0
Vessel B
Inlet
Pressure
psi
10.0
7.0
7.0
7.0
6.0
4.0
4.0
7.0
17.0
16.0
17.0
19.0
15.0
15.0
17.0
14.0
14.0
17.0
12.0
15.0
13.0
17.0
15.0
15.0
23.0
19.0
25.0
25.0
27.0
16.0
19.0
19.0
15.0
13.0
10.0
18.0
19.0
12.0
13.0
10.0
12.0
7.0
Oulet
Pressure
psi
12.0
8.0
7.0
8.0
7.0
6.0
6.0
8.0
20.0
18.0
19.0
21.0
17.0
17.0
19.0
16.0
16.0
19.0
14.0
17.0
15.0
18.0
18.0
17.0
25.0
22.0
27.0
27.0
28.0
20.0
21.0
21.0
16.0
15.0
12.0
20.0
21.0
14.0
15.0
12.0
14.0
9.0
Ap
psi
2.0
1.0
0.0
1.0
1.0
2.0
2.0
1.0
3.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
1.0
3.0
2.0
2.0
3.0
2.0
2.0
1.0
4.0
2.0
2.0
1.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
>
-------
EPA Arsenic Demonstration at WRWC in Bow, NH- Summary of Daily System Operational Data (Page 5 of 5)
Week No.
25
26
27
28
Date
3/28/2005
3/29/2005
3/30/2005
3/31/2005
4/1/2005
4/2/2005
4/3/2005
4/4/2005
4/5/2005
4/6/2005
4/7/2005
4/8/2005
4/9/2005
4/10/2005
4/11/2005
4/12/2005
4/13/2005
4/14/2005
4/15/2005
4/16/2005
4/17/2005
4/18/2005
4/19/2005
4/20/2005
4/21/2005
4/22/2005
4/23/2005
4/24/2005
Avg
Operation
Hours
hr
8.2
8.5
9.6
8.9
8.5
9.8
9.8
8.7
7.7
8.0
7.8
8.5
9.1
10.2
9.2
10.2
7.5
8.8
9.4
10.6
10.8
9.6
10.0
10.2
9.0
24.7
7.8
9.0
Cumulative
Operation
Hours
hr
1479.0
1487.5
1497.1
1506.0
1514.5
1524.3
1534.1
1542.8
1550.5
1558.5
1566.3
1574.8
1583.9
1594.1
1603.3
1613.5
1621.0
1629.8
1639.2
1649.8
1660.6
1670.2
1680.2
1690.4
1699.4
1724.1
1731.9
1740.9
Oulet Magnetic Meter
Outlet
Flowrate
gpm
37.8
39.1
41.6
39.9
40.7
42.3
43.9
40.6
42.5
44.4
38.7
39.6
42.5
42.5
44.6
42.4
47.3
41.4
10.6
39.3
45.4
44.7
40.9
41.9
44.6
27.4
44.1
41.5
Outlet
Totalizer
gal
3,883,085
3,902,013
3,922,384
3,941 ,732
3,960,622
3,982,195
4,003,448
4,022,552
4,038,787
4,056,802
4,074,577
4,093,908
4,113,962
4,135,968
4,155,862
4,178,409
4,195,027
4,214,799
4,235,652
4,258,123
4,280,778
4,300,836
4,321 ,862
4,343,599
4,363,147
4,405,545
4,422,047
4,440,999
Daily
Flow
Totalizer
gal
16,706
18,928
20,371
19,348
18,890
21 ,573
21 ,253
19,104
16,235
18,015
17,775
19,331
20,054
22,006
1 9,894
22,547
16,618
19,772
20,853
22,471
22,655
20,058
21 ,026
21 ,737
1 9,548
42,398
1 6,502
18,952
Cumulative
Volume
Treated
gal
3,299,638
3,318,566
3,338,937
3,358,285
3,377,175
3,398,748
3,420,001
3,439,105
3,455,340
3,473,355
3,491,130
3,510,461
3,530,515
3,552,521
3,572,415
3,594,962
3,61 1 ,580
3,631 ,352
3,652,205
3,674,676
3,697,331
3,717,389
3,738,415
3,760,152
3,779,700
3,822,098
3,838,600
3,857,552
Cumulative
Bed
Volumes
Treated
5190
5220
5252
5282
5312
5346
5379
5409
5435
5463
5491
5521
5553
5587
5619
5654
5680
5711
5744
5780
5815
5847
5880
5914
5945
6011
6037
6067
Vessel A
Inlet
Pressure
psi
15.0
14.0
16.0
16.0
16.0
15.0
14.0
14.0
16.0
16.0
11.0
14.0
16.0
15.0
16.0
15.0
16.0
15.0
13.0
13.0
14.0
15.0
16.0
15.0
16.0
8.0
13.0
14.0
Outlet
Pressure
psi
16.0
14.0
16.0
16.0
16.0
15.0
13.0
13.0
10.0
10.0
11.0
10.0
10.0
10.0
10.0
15.0
16.0
14.0
13.0
13.0
13.0
15.0
15.0
15.0
15.0
7.0
13.0
13.0
Ap
psi
1.0
0.0
0.0
0.0
0.0
0.0
1.0
1.0
6.0
6.0
0.0
4.0
6.0
5.0
6.0
0.0
0.0
1.0
0.0
0.0
1.0
0.0
1.0
0.0
1.0
1.0
0.0
1.0
Vessel B
Inlet
Pressure
psi
13.0
12.0
13.0
13.0
14.0
13.0
12.0
12.0
13.0
13.0
13.0
12.0
13.0
12.0
13.0
12.0
14.0
12.0
10.0
10.0
11.0
13.0
13.0
13.0
13.0
4.0
11.0
12.0
Oulet
Pressure
psi
15.0
13.0
15.0
15.0
15.0
14.0
14.0
13.0
16.0
15.0
15.0
12.0
15.0
14.0
15.0
14.0
15.0
13.0
12.0
12.0
13.0
14.0
15.0
15.0
15.0
7.0
13.0
13.0
Ap
psi
2.0
1.0
2.0
2.0
1.0
1.0
2.0
1.0
3.0
2.0
2.0
0.0
2.0
2.0
2.0
2.0
1.0
1.0
2.0
2.0
2.0
1.0
2.0
2.0
2.0
3.0
2.0
1.0
>
NM = Not Measured
NA = Not Available
-------
APPENDIX B
ANALYTICAL RESULTS
-------
Analytical Results
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
NO3-N
Orthophosphate
Silica (as SiO2)
Sulfate
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (total soluble)
As (particulate)
As (III)
As(V)
Total Fe
Dissolved Fe
Total Mn
Dissolved Mn
103
mg/L(a)
mg/L
mg/L
mg/L0"
mg/L
mg/L
NTU
S.U.
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(!l)
Mg/L
Mg/L
Mg/L
Hg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
10/13/04
-------
Analytical Results
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
N03-N
Orthophosphate
Silica (as SiO2)
Sulfate
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (total soluble)
As (particulate)
As (III)
As(V)
Total Fe
Dissolved Fe
Total Mn
Dissolved Mn
103
mg/L(!l)
mg/L
mg/L
mg/L®
mg/L
mg/L
NTU
S.U.
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/L(a)
mg/L(a)
jjg/L
jjg/L
jjg/L
jjg/L
jjg/L
jjg/L
jjg/L
jjg/L
jjg/L
11/16/04
-------
Analytical Results
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
N03-N
Orthophosphate
Silica (as SiO2)
Sulfate
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (total soluble)
As (particulate)
As (III)
As(V)
Total Fe
Dissolved Fe
Total Mn
Dissolved Mn
103
mg/L«
mg/L
mg/L
rng/L*'
mg/L
mg/L
NTU
s.u.
°c
mg/L
mV
mg/L
mg/L
mg/L(!l)
mg/L(a)
mg/L(!l)
re/L
re/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
01/18/05
IN
-
66
-
-
0.3
19.7
-
0.5
7.5
12.4
6.0
238
-
-
-
-
-
46.1
-
-
-
-
<25
-
0.6
-
AP
-
35
-
-
0.2
20.1
-
<0.1
6.5
12.6
4.5
207
0.3
0.3
-
-
-
46.3
-
-
-
-
<25
-
0.8
-
TA
TB
2.6
33
-
-
<0.05
22.7
-
<0.1
6.4
12.3
4.0
548
0.2
0.3
-
-
-
15.1
-
-
-
-
<25
-
3.0
-
35
-
-
<0.05
25.3
-
<0.1
6.4
12.3
3.9
584
0.2
0.2
-
-
-
2.1
-
-
-
-
<25
-
2.8
-
02/01/05
IN
-
69
0.9
0.22
0.1
18.7
11.0
<0.1
7.4
11.5
6.6
211
-
-
84.0
65.9
18.1
54.1
54.6
<0.1
0.5
54.1
<25
<25
0.5
0.5
AP
-
43
1.0
0.19
0.06
18.5
47.0
<0.1
6.5
11.6
5.6
587
0.2
0.2
81.5
64.0
17.5
54.5
54.4
0.1
0.5
53.9
<25
<25
3.3
0.5
TA
TB
3.4
37
0.7
0.23
<0.05
21.1
48.0
<0.1
6.4
11.4
5.3
591
0.2
0.2
85.0
66.6
18.4
24.4
24.8
<0.1
0.4
24.4
<25
<25
1.1
1.2
41
0.3
0.24
<0.05
24.9
48.0
<0.1
6.5
11.2
5.4
586
0.2
0.2
89.6
70.0
19.6
5.0
5.0
<0.1
0.4
4.6
<25
<25
1.5
1.3
02/15/05
IN
-
69
-
-
<0.05
20.0
-
<0.1
7.4
11.5
NA(C)
212
-
-
-
-
-
45.5
-
-
-
-
<25
-
0.7
-
AP
-
45
-
-
0.05
20.1
-
<0.1
6.5
11.5
NA(C)
580
0.3
0.3
-
-
-
46.1
-
-
-
-
<25
-
0.7
-
TA
TB
3.8
36
-
-
<0.05
22.9
-
<0.1
6.3
11.5
NA(C)
594
0.3
0.2
-
-
-
17.2
-
-
-
-
<25
-
1.4
-
38
-
-
<0.05
24.9
-
<0.1
6.3
11.2
NA(C)
595
0.2
0.2
-
-
-
3.3
-
-
-
-
<25
-
2.4
-
03/01/05
IN
-
120
-
-
<0.05
19.7
-
<0.1
7.3
11.9
5.1
195
-
-
-
-
-
49.1
-
-
-
-
<25
-
1.1
-
AP
-
61
-
-
<0.05
19.9
-
<0.1
6.5
12.0
3.9
607
0.5
0.5
-
-
-
49.8
-
-
-
-
<25
-
1.9
-
TA
TB
4.3
62
-
-
<0.05
22.0
-
<0.1
6.4
11.8
3.9
610
0.5
0.4
-
-
-
22.3
-
-
-
-
<25
-
0.5
-
68
-
-
<0.05
23.9
-
<0.1
6.4
11.5
3.9
608
0.4
0.5
-
-
-
3.9
-
-
-
-
<25
-
1.1
-
(a) as CaCO3. (b) as PO4. (c) DO probe not working properly.
IN = inlet; AP = after pH adjustment and after pre-chlorination;
TA = after Vessel A; TB = after Vessel B; TT = after vessels combined; NA = data not available.
-------
Analytical Results
Cd
Sampling Date
Sampling Location
Parameter Unit
Bed Volume
Alkalinity
Fluoride
N03-N
Orthophosphate
Silica (as SiO2)
Sulfate
Turbidity
PH
Temperature
DO
ORP
Free Chlorine
Total Chlorine
Total Hardness
Ca Hardness
Mg Hardness
As (total)
As (total soluble)
As (particulate)
As (III)
As(V)
Total Fe
Dissolved Fe
Total Mn
Dissolved Mn
103
mg/L(a)
mg/L
mg/L
rng/L*'
mg/L
mg/L
NTU
S.U.
°C
mg/L
mV
mg/L
mg/L
mg/L(a)
mg/Lw
mg/L(a)
re/L
re/L
re/L
re/L
|xg/L
re/L
Hg/L
re/L
|xg/L
03/15/05
IN
-
77
69
-
-
<0.05
<0.05
21.4
20.3
-
<0.1
<0.1
7.4
11.9
NA(C)
213
-
-
-
-
-
48.1
47.8
-
-
-
-
<25
<25
-
2.0
1.9
-
AP
-
35
39
-
-
<0.05
<0.05
21.4
20.8
-
<0.1
<0.1
6.6
11.9
NA(C)
608
0.5
0.5
-
-
-
46.9
47.0
-
-
-
-
<25
<25
-
1.9
1.8
-
TA
TB
4.8
37
37
-
-
<0.05
<0.05
23.9
22.7
-
<0.1
<0.1
6.3
11.7
NA(C)
606
0.3
0.4
-
-
-
23.0
23.1
-
-
-
-
<25
<25
-
0.6
0.5
-
38
37
-
-
<0.05
<0.05
24.4
24.3
-
<0.1
<0.1
6.3
11.6
NA(C)
608
0.4
0.4
-
-
-
6.9
6.8
-
-
-
-
<25
<25
-
0.3
0.3
-
03/29/05(tl)
IN
-
66
0.9
0.2
<0.05
19.8
11.0
<0.1
7.4
11.7
5.3
212
-
-
95.4
75.8
19.6
48.9
48.2
0.7
0.7
47.5
<25
<25
1.2
1.2
AP
-
33
1.0
0.2
<0.05
19.7
51.0
<0.1
6.1
11.5
4.3
577
0.4
0.4
93.4
72.7
20.7
50.0
49.7
0.3
0.6
49.1
<25
<25
0.9
1.0
TA
TB
5.2
29
0.9
0.2
<0.05
21.4
48.0
<0.1
6.1
11.4
4.7
590
0.4
0.3
101.4
77.2
24.2
21.0
20.8
0.2
0.6
20.2
<25
<25
1.2
1.4
28
0.8
0.3
<0.05
23.5
46.0
0.3
6.1
11.4
4.4
594
0.3
0.3
98.5
75.7
22.8
5.5
5.5
<0.1
0.7
4.8
<25
<25
1.5
1.4
04/12/05
IN
-
67
-
-
<0.05
20.7
-
<0.1
7.3
11.7
4.8
192
-
-
-
-
-
42.8
-
-
-
-
<25
-
0.1
-
AP
-
28
-
-
<0.05
20.1
-
0.1
6.1
11.6
3.9
560
0.4
0.3
-
-
-
41.5
-
-
-
-
<25
-
0.1
-
TA
TB
5.7
44
-
-
<0.05
23.0
-
<0.1
6.4
11.7
4.8
577
0.3
0.4
-
-
-
26.3
-
-
-
-
<25
-
0.5
-
42
-
-
<0.05
25.1
-
<0.1
6.5
11.5
4.6
578
0.4
0.3
-
-
-
5.8
-
-
-
-
<25
-
<0.1
-
(a) as CaCO3. (b) as PO4. (c) DO probe not working properly, (d) On-site water quality parameters measured on March 28, 2005.
IN = inlet; AP = after pH adjustment and after pre-chlorination; TA = after Vessel A; TB = after Vessel B; TT = after vessels combined; NA = data not available.
------- |