Quality of Ground Water and Finished Water of Community Water Systems – Preliminary Findings U.S....

Quality of Ground Water and Quality of Ground Water and Finished Water of Community Finished Water of Community

Water SystemsWater Systems – – Preliminary FindingsPreliminary Findings

U.S. Department of InteriorU.S. Geological Survey

Jessica A. HoppleJessica A. HoppleMay 11, 2006May 11, 2006

San Jose, CaliforniaSan Jose, California

Focus of Today’s TalkFocus of Today’s Talk

• Source Water Quality Assessment Source Water Quality Assessment (SWQA) Design(SWQA) Design

• Occurrence of Compounds in Source Occurrence of Compounds in Source Water WellsWater Wells

• Quality of Source and Finished Water and Quality of Source and Finished Water and Comparison to Human-Health Comparison to Human-Health BenchmarksBenchmarks

SWQA DesignSWQA Design• Phase 1Phase 1

– 260 compounds 260 compounds analyzedanalyzed

– 214 source water wells 214 source water wells sampledsampled

• Phase 2Phase 2– Frequently occurring Frequently occurring

compounds in Phase 1 compounds in Phase 1 analyzedanalyzed

– 86 source and finished 86 source and finished water sites sampledwater sites sampled

Twelve SWQAs Completed Twelve SWQAs Completed

Study area2

2

• Largest Largest producing producing Community Community Water Supply Water Supply wells wells

• Important Important aquifers for aquifers for drinking water drinking water supplysupply

0 10 20 30 40 50 60 70

Number of Compounds

Number in group

Number withhuman-health benchmarks

Herbicides and Herbicide DegradatesHerbicides and Herbicide Degradates

FungicidesFungicides

Manufacturing AdditivesManufacturing Additives

Insecticides and Insecticide DegradatesInsecticides and Insecticide Degradates

Organic Synthesis CompoundsOrganic Synthesis Compounds

Personal Care and Domestic Use ProductsPersonal Care and Domestic Use Products

SolventsSolvents

Gasoline, Oxygenates, and DegradatesGasoline, Oxygenates, and Degradates

Fumigant Related CompoundsFumigant Related Compounds

Pavement- and Combustion-derived CompoundsPavement- and Combustion-derived Compounds

Plant- or Animal-derived BiochemicalsPlant- or Animal-derived Biochemicals

Disinfection By-productsDisinfection By-products

Refrigerants and PropellantsRefrigerants and Propellants

Compounds Monitored Have Compounds Monitored Have Different UsesDifferent Uses

Occurrence of Compounds in Occurrence of Compounds in Source Water Wells (Phase 1)Source Water Wells (Phase 1)

• 260 compounds 260 compounds analyzedanalyzed

– 134 were not detected134 were not detected

– 57 were detected 3 or 57 were detected 3 or more timesmore times

Compounds Detected in Compounds Detected in Source Water WellsSource Water Wells

Most Frequently DetectedMost Frequently Detected(11 – 37 % detection frequency)(11 – 37 % detection frequency)

Emerging contaminants (ECs)Emerging contaminants (ECs)(1 – 6 % detection frequency)(1 – 6 % detection frequency)

AtrazineAtrazine

TetrachloroetheneTetrachloroethene

TrichloroetheneTrichloroethene

DeethylatrazineDeethylatrazine

PrometonPrometon

MetolachlorMetolachlor

DeisopropylatrazineDeisopropylatrazine

MTBEMTBE

SimazineSimazine

Chloroform

4-tert-Octylphenol

CaffeineDiethoxy octylphenolMenthol

Methyl salicylate

Monoethoxy octylphenol

TributylTributyl phosphatephosphate

TriphenylTriphenyl phosphatephosphate

AHTN

Quality of Source and Finished Quality of Source and Finished Water and Comparison to Human-Water and Comparison to Human-

Health Benchmarks (Phase 2)Health Benchmarks (Phase 2)

Maximum Contaminant Levels (MCLs)—Regulated Compounds

Health-Based Screening Levels(HBSLs)—Unregulated Compounds

Frequency of Detection Similar in Frequency of Detection Similar in Source and Finished WaterSource and Finished Water

AtrazineAtrazine

TetrachloroetheneTetrachloroethene

TrichloroetheneTrichloroethene

DeethylatrazineDeethylatrazine

PrometonPrometon

MetolachlorMetolachlor

DeisopropylatrazineDeisopropylatrazine

MTBEMTBE

SimazineSimazine

0 20 40 60 80 100

Source waterFinished water

Frequency of detection, in percent

- - Most Frequently DetectedMost Frequently Detected

AtrazineAtrazine

TetrachloroetheneTetrachloroethene

TrichloroetheneTrichloroethene

DeethylatrazineDeethylatrazine

PrometonPrometon

MetolachlorMetolachlor

DeisopropylatrazineDeisopropylatrazine

MTBEMTBE

SimazineSimazine

Concentrations Tend to be Less in Concentrations Tend to be Less in Finished Than Source WaterFinished Than Source Water

0.001 0.01 0.1 1 10 1000.001

0.01

0.1

1

10

100

Concentration in source water, in micrograms per liter

Co

nce

ntr

atio

n in

fin

ish

ed w

ater

,

i

n m

icro

gra

ms

per

lite

r

- - Most Frequently DetectedMost Frequently Detected

Frequency of Detection Not Always Frequency of Detection Not Always Similar for Emerging ContaminantsSimilar for Emerging Contaminants

4-tert-Octylphenol4-tert-Octylphenol

CaffeineCaffeine

Diethoxy octylphenolDiethoxy octylphenol

MentholMenthol

Methyl salicylateMethyl salicylate

Monoethoxy octylphenolMonoethoxy octylphenol

Tributyl phosphateTributyl phosphate

Triphenyl phosphateTriphenyl phosphate

AHTNAHTN

0 10 20 30 40 50

Source waterFinished water

Frequency of detection, in percent

Concentration of ECs Typically Not Concentration of ECs Typically Not Similar in Source and Finished WaterSimilar in Source and Finished Water

4-tert-Octylphenol4-tert-Octylphenol

CaffeineCaffeine

Diethoxy octylphenolDiethoxy octylphenol

MentholMenthol

Methyl salicylateMethyl salicylate

Monoethoxy octylphenolMonoethoxy octylphenol

Tributyl phosphateTributyl phosphate

Triphenyl phosphateTriphenyl phosphate

AHTNAHTN

0.001 0.01 0.1 10.001

0.01

0.1

1

Concentration in source water, in micrograms per liter

Co

nce

ntr

atio

n in

fin

ish

ed w

ater

,

i

n m

icro

gra

ms

per

lite

r

0.001 0.01 0.1 1 10 100

Source water Finished water

Concentration, in micrograms per liter

Concentrations in Finished Water Concentrations in Finished Water Below Human-Health BenchmarksBelow Human-Health Benchmarks

MCLsMCLs

HBSLsHBSLs

No No MCLs MCLs or or HBSLsHBSLs

AtrazineAtrazine

TetrachloroetheneTetrachloroetheneTrichloroetheneTrichloroethene

DeethylatrazineDeethylatrazine

PrometonPrometonMetolachlorMetolachlor

DeisopropylatrazineDeisopropylatrazine

MTBEMTBE

SimazineSimazine

ConclusionsConclusions• ~ ½ of the compounds analyzed were not ~ ½ of the compounds analyzed were not

detected in source water wellsdetected in source water wells

• Frequently detected compounds – Frequently detected compounds – usually present in both source and usually present in both source and finished water wellsfinished water wells

• Emerging contaminants – not always Emerging contaminants – not always present in both source and finished water present in both source and finished water wellswells

• Concentrations usually were orders of Concentrations usually were orders of magnitude below human-health magnitude below human-health benchmarksbenchmarks

Information on NAWQA:Email: nawqa_whq@usgs.govWorld Wide Web: http://water.usgs.gov/nawqa

Information on SWQAs: Name: Greg DelzerEmail: gcdelzer@usgs.gov Phone: (605) 394-3230

Information on NAWQA:Email: nawqa_whq@usgs.govWorld Wide Web: http://water.usgs.gov/nawqa

Information on SWQAs: Name: Greg DelzerEmail: gcdelzer@usgs.gov Phone: (605) 394-3230