Groundwater Under Direct Influence of Surface Water, What To Do?

Groundwater Under Direct Influence of
Surface Water, What To Do?
Presented by:
Michael S. Johnson, P.E.
Buck, Seifert & Jost, Inc.
Presented at:
American Water Works Association (AWWA)
Annual Spring Conference, Atlantic City, NJ
March 17-20, 2015
Outline
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LT2ESWTR
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Treatment Techniques
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EPA
Factors that trigger
compliance
UV, Filter, Chemical, etc.
Case Studies
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Two (2) wells
Start up/Operation
Procedures
Background
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LT2ESWTR
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Improve drinking water quality
Protection from disease causing
microorganisms and contaminants
Applies to all PWS that use SW or GWUDISW
GWUDISW Factors (varies by state)
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Type of well (spring, horizontal collection well,
unconfined aquifer or recharge well)
Adjacent to surface water
Well Construction (shallow/deep, annular space)
Water Quality (periodically +TC or +E. Coli)
Background
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Hydrogeological Investigation
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Hydraulic connection (seismic reflection survey, seepage
investigation, or thermal infrared imagery)
Microscopic Particulate Analysis (MPA)
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Low, Medium, or High Risk
Algae, Diatoms, Pollen, Protozoa, Giardia, Crypto, etc.
You, after Medium or High Risk MPA?
LT2 Rule
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2-log Crypto (or 5.5 if raw water not monitored)
3-log Giardia, and
4-log Virus
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Treatment Options
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Watershed Control
Alternative Source/Intake
Bank Filtration
Pre-sedimentation
Lime Softening
Filter
Chlorine Dioxide
Ozone
UV
Membrane Filtration
Filters
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Refer to State Standards
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Bag and Cartridge Filters
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Operator licensing
Low Loading capacity for small systems
Discard filter after expended
Effectively removes Crypto (2-5 μm)
and Giardia (5-10μm)
Challenge Testing
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Product specific, not site specific
o
o
o
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Full scale
Challenge particulate
Test solution concentration
Up to 2 log for bag or cartridge filter showing 3 log removal
Up to 2.5 log removal in series showing 3 log removal
Filters
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Advantage
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Low maintenance, low capital,
minimal training
Disadvantage
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NSF, Headloss, Replace filters,
redundancy, biofilm clogging, limit
surges, larger flows consider
membrane or other
Filters
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Turbidity < 3NTU or less depending on
manufacturer, may need pre-treatment
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UV treatment may require pre-treatment
if >1 NTU
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MPA proof after installed?
Ultraviolet (UV)
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Damages microorganisms and prevents replication
No residual
Validation testing, see UV Disinfection Guidance Manual
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In English
Partial Exhibit 13.1 UV Dose Requirements – mJ/cm2
Ultraviolet (UV)

Two (2) types of UV devices typically
used:
1. Medium Pressure (MP) and
2. Low Pressure High Output (LPHO)
More information see Ultraviolet Disinfection
Guidance Manual at:
http://www.epa.gov/OGWDW/disinfection/lt2/
pdfs/guide_lt2_uvguidance.pdf
Ultraviolet (UV)
LPHO vs. MP
 Reactors can be s-shaped, u-shaped, or in-line
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Lamp life
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LPHO 8,000 to 12,000 hours
MP 4,000 to 8,000 hours
Power
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Typically LPHO require larger footprint
LPHO require less power, more lamps
Sleeve Cleaning
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LPHO use Off-line chemical clean (OCC) systems, more
labor
MP use On-line Mechanical (OMC) systems, more parts to
replace
Ultraviolet (UV)
Examples of:
S-Shape
U-Shape
In-line
Ultraviolet (UV)
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Validation of UV device
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No increasers US or DS within 10 times diameter of reactor
PWS monitor for flow rate, lamp status and UV intensity
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UV absorbance (or UVT) if in dose monitoring strategy
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Fouling: Ca+2, Alkalinity, Mn+2, pH, Fe+2 and Hardness
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Off-spec reporting
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Advantages: Lowest cost treatment for Crypto and Giardia,
no DBP, not impacted by pH or temperature
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Disadvantages: no residual, high UV dose for Virus
inactivation, power quality
Full Scale Implementation
 Example 1
 200gpm well @ 360TDH,
200’ Deep Well
 12’ x 22’ Wellhouse
 Seaquest and Hypo
 Wetlands nearby
Prior to Construction
 From Determination of
GWUDISW, 18 Month
Schedule To Implement
Full Scale Implementation
As Constructed
Construct within existing
building
New 200gpm @ 454 TDH VTP
Waste/blow off piping
Harmsco MUNI-3-3FL
Full Scale Implementation
As Constructed
Harmsco
MUNI-3-3FL
InLine 200+ DVGW
UV
6”x6” Tee
Flow meter
Surge Antic. Valve
M.O. Spring Return
BFV
35LF of 36ӯ DIP
Full Scale Implementation
Example 2
 1200gpm well @
609TDH, 55’ Deep Well
 16’ x 13’ Wellhouse
 Seaquest and Hypo
 Floodplain and High
Pressure
 From Determination of
GWUDISW, 18 Month
Schedule To Implement
Prior to Construction
Full Scale Implementation
Prior to Construction
Full Scale Implementation
Raise All Treatment
Components
New 1400gpm @ 372 VTP
(Lower head)
New Elevated
Treatment Enclosure
Full Scale Implementation
Parallel Treatment Trains
With And Without Grating
Full Scale Implementation
As Constructed
UV Reactor
Y-Strainer
Full Scale Implementation
As Constructed
Surge Anticipating Valve
Spring Return Hydraulic BFV
Booster Pump
Surge Anticipating Valve Vault
Summary
 NSF Listing
 UV Validation
 UV and Filter Treatment: multiple barriers
 Think Vertical
 Start-up and testing
 Learning Process
o We were assisted by and would like to thank:
 Entire staff at United Water special mention to:



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Gerry Remsen, III, P.E.
Bill Prehoda, P.G.
Nick Curcio
Bob Raczko, P.E.
 Sam Rulli, P.E., Rockland County DOH
 Dan Miller, Ph.D, Rockland County DOH
 Brock Rogers, P.E., NYS DOH
 Ronald von Autenried, P.E., BS&J
 J. Fletcher Creamer & Son, Inc. (Contractor)
 Aquionics Inc. (UV)
 Harmsco Filtration Products (Filter)
 Quality Controls, Inc. (Fail Safe BFV)
 Baker Manufacturing Company, LLC (Booster Pump)
Thank you!
Michael Johnson
[email protected]
201-767-3111, ext. 111