Ben Wright PE Bill Becker PE PhD Dave Reckhow PhD Steve Schindler 2013 NYC Watershed Tifft Science amp Technical Symposium Frumhoff et al 2007 Peduzzi 2004 Water Quality Impacts of Extremes ID: 248215
Download Presentation The PPT/PDF document "Advanced Techniques for Monitoring NOM a..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Advanced Techniques for Monitoring NOM and Controlling DBPs
Ben Wright, PEBill Becker, PE, PhDDave Reckhow, PhDSteve Schindler
2013 NYC Watershed/Tifft Science & Technical SymposiumSlide2Slide3
Frumhoff
et al, 2007
Peduzzi
, 2004Slide4
Water Quality Impacts of Extremes
Heavy precipitation
Contaminants, nutrients, and sediment flushed into rivers and lakesOverloading of storm and wastewater systems (increasing risk of contamination)
Severe drought
Concentrates point source contaminants in raw drinking water supplies
Water quality can degrade as reservoirs drop
NOM levels can peak following reservoir refillSlide5
Droughts and Nutrients
NOAA Earth ObservatorySlide6
Algal Blooms
Blooms are caused by ideal combination of (typically higher) temperatures and nutrients
2011 bloom on Lake ErieSlide7
Research to Characterize NOM
Water Research Foundation - On-Line NOM Characterization: Advanced Techniques for Controlling DBPs and for Monitoring Changes in NOM under Future Climate NYC DEPNYSERDA
- Climate change and water quality - Impacts and adaptation strategies for NYS utilitiesMCWA, MVWA, OCWA, SCWA, Waterloo, Watertown, Latham Water, and NYC DEPSlide8
Climate Comparison
Downscaled GCM data from both DEP and NYSERDA Will compare projected weather patterns with historicalSampling in spring and summer for reservoirs in VA and NCWill compare NY and southern reservoir lab results
Carvins
Cove, Roanoke, VA
North Fork Reservoir, Asheville, NCSlide9
NOM Characterization MethodsSlide10
Direct Hydrophobicity Test
10
Hydrophobic NOMRetained on XAD-8TOC#1-TOC#2
Mesophilic NOMRetained on XAD-4, but not on XAD-8TOC#2-TOC#3Hydrophilic NOM
Not retained
TOC#3
XAD-8
Test Water
XAD-4
To Waste
TOC#1
TOC#2
TOC#3Slide11
Elution-Based Hydrophobicity Test
Actual recovered NOM from each resinHydrophobic = TOC #4Mesophilic = TOC #5Slide12
Figure 1 Experimental setup for PRAM. SPE cartridges contained 100 mg of sorbent with a total volume of 1.5
mL
and average pore size of 60 Å. The retention coefficient (RC) is calculated based on the maximum breakthrough concentration and the initial concentration. C-18, C-8, and C-2 are
nonpolar
sorbents; Silica,
Diol
, and Cyanide (CN) are polar sorbents; Amino (NH-2) is a weak anion exchange and SAX is the strong anion exchanger.
Published in: Fernando L. Rosario-Ortiz; Shane Snyder; I. H. (Mel) Suffet;
Environ. Sci. Technol.
2007,
41, 4895-4900.
DOI: 10.1021/es062151t
Copyright © 2007 American Chemical Society
SCX
Ph
UV/Vis + TOC
Differences between UMass method and the Rosario-Ortiz method are in red
Polarity Rapid
Assement
Method (PRAM)Slide13
Florescence SpectroscopySlide14
What is Fluorescence Spectroscopy
Light interacts with organic matter (OM) in waterSpecific wavelengths excite molecules (fluorophores) within the OM causing them to fluoresce
Chemical composition, source, cause different fluorescence signaturesExcitation-emission matrixes are becoming more popular for determining the amount of dissolved OM in the waterSlide15
Typical Excitation Emission Matrix
Region ID
Description
Region I
Microbial Byproducts, Proteins, Biopolymers
Region II
Fulvic
-Like Compounds
Region III
Humic
-Like CompoundsSlide16
DOM and Fluorescence
Colored dissolved organic matter (CDOM) is optically active fraction of DOMLand use, urban growth/development, climate change, severe weather impact all impact source and quantity of raw water DOMTreatment processes can remove DOMExample: decrease in fluorescence with increase in coagulant dose
Raw
20 mg/L
PACl
4
0 mg/L
PAClSlide17
How Can Fluorescence Help Utilities
Identify potential correlations between certain types of DOM and DBPsOptimize coagulation and other processesIdentify source water changesIdentify impact of extreme weather (both flooding and drought) on water quality
Identify sources of DOMIdentify areas of potential fouling for membrane applicationsSlide18
Spectral Analysis
S::CAN spectro::lyserMeasures complete absorbance spectra of waters (200-750 nm)
Calibrated with identical unit in UMASS labInstalled at DEP April 2013Research Goal: evaluate ability of spectro::
lyser to measure relationships between spectral features, NOM fractions, and DBP precursorsSlide19Slide20
Utilizing Improved Methods
Source water quality Watershed improvement/protectionSource rotationTreatment process optimizationDistribution system modificationsSlide21
Stage 2 Compliance Tool Kit
The Manual and web tool provide guidance for complying with Stage 2.The goal of the materials is to help utilities:Evaluate potential compliance relative to a goalUnderstand DBP reduction strategies
Compare DBP reduction strategies using system specific information to estimate:Percent DBP reductionsCostSlide22
Available Data
Determine Data Available:
DBPs:
Stage 1
Quarterly since at least 2002 (for larger systems)
IDSE (between 2006 and 2009)
What type of IDSE performed?
Standard Monitoring
Hydraulic Model
System Specific Study
Data used to satisfy IDSE
1 – 6 measurements per sample site for 1 year
Additional / Non-Compliance
Continued monitoring of IDSE sites or early monitoring of selected compliance sitesSlide23
Other Useful Data
Population ServedTOCRaw water alkalinity
Raw Water BromideFinished water pHAdvanced TOC characterization
UV254 and/or SUVAChlorine usage dataTotal chlorine usage in plantResidual chlorine levels
Distribution System
Locational
Water Age (if known)
Seasonal Demand
System Storage CapacitySlide24
Web Tool Generated Report
24Slide25
Strategies Considered
25
SourceTreatment
DistributionSource Change or BlendingSource ManagementPurchase Water
Point of Chlorination
Optimize Chlorine Dose
Optimize / Add PAC
Optimize Coagulation for TOC
Change Coagulation
Change Primary Disinfection
Advanced TOC removal – GAC
Advanced TOC removal - MIEX
Membranes
Optimize DS
Chlorination / Booster Chlorination
Change Secondary disinfection
Optimize Storage Operation
In-Tank TreatmentSystem FlushingSlide26
Determining Impact of Strategies
Each Strategy linked to an “optimum” DBP reductionUsers will answer a series of questions about their systems to hone in on “actual” DBP reduction potentialCost curves for each strategy are also linked to questionnaire responses
26Slide27
Thank You!
Ben Wrightbwright@hazenandsawyer.comBill Beckerwbecker@hazenandsawyer.com
27