Groundwater Quality Beneath an Area of Urban Residential and Commercial Land Use, Mobile, Alabama 2011 2012 Alabama Water Resources Conference September

Groundwater Quality Beneath an Area of Urban Residential and Commercial Land Use, Mobile,

Alabama 20112012 Alabama Water Resources Conference

September 6, 2012, Perdido Beach Resort, Orange Beach, AlabamaRichard Moreland, USGS, Montgomery, Alabama

Study background Study design Methods Results

Mobile Urban Land Use Study

National Water Quality Assessment (NAWQA) What is the condition of

Nations streams, rivers, and groundwater?

How are these changing over time?

How do Natural and human activities affect these conditions, and where are they most pronounced.


31 wells installed in 2010 Installed with Geoprobe direct push

machine. Two inch diameter, depths ranging from

14 to 69 feet below land surface.

29 wells sampled in 2011 – full suite of QW constituents (Nutrients, major ions, trace metals, pesticides, VOCs, DOC). Two wells were dry. Wells were developed with inertial surge pump. Purged of at least three casing volumes and

pumped until field readings of Temperature, Specific Conductance, pH, Dissolved Oxygen, and Turbidity were stable.



Residential and Light Commercial land use areas in the Mobile metropolitan area. Eliminate effects of

industrial areas and transportation corridors

Post 1970’s construction. Synthesis of 2001 MRLC

data with mid 2000’s aerial photography.


Residential and light commercial land use areas


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Alluvial, coastal, and low terrace deposits

Citronelle Formation

High terrace deposits

Miocene Series undifferentiated

Geology


Quality Control Samples

Detections for nickel, manganese, styrene at levels below environmental samples.

Detections for ammonia and nitrite below environmental sample levels. Only one ammonia and two nitrite detections in environmental samples.

**Dissolved Organic Carbon had two detections in blanks, one of which was greater than any environmental sample.**


Field Parameters

Major Ions Piper Diagram


Selected Major Ions

Concentrations


MCL


Select Nutrients

Mil

lig

ram

s

pe

r L

ite

r


Dissolved Organic Carbon


Select Metals

Mic

rog

ram

s p

er

lite

r

2-Chlo

ro-4

-isop

ropy

lamino

-6-a

mino

-s-tr

iazine

Atrazin

e

2-Hyd

roxy

-4-is

opro

pylam

ino-6

-eth

ylam

ino-s

-triaz

ine

Dieldr

in

Fipron

il

Fipron

il sulf

ide

Fipron

il sulf

one

Brom

acil

Imida

clopr

id

Simaz

ine

alpha

-End

osulf

an

Desulf

inylfip

ronil

Ethion

, wat

er

Imaz

aquin

2-Chlo

ro-6

-eth

ylam

ino-4

-am

ino-s

-triaz

ine

Desulf

inylfip

ronil

am

ide

Dicam

ba

Endos

ulfan

sulf

ate

Met

olach

lor

Piclor

am

Prom

eton

Triclop

yr0

10

20

30

40

50

60

70Pe

rcen

t of

Sam

ples Pesticides

144 analytes 22 analytes

detected


0.001

0.01

0.1

1

10

Conc

entr

ation

in

Mic

rogr

ams

per L

iter

Pesticides


MCL(3.0)

RSD(0.002)


Trichlo

rom

ethan

e

Styre

ne

Brom

odichlo

rom

ethan

e

Carbon d

isulfi

de

Tetra

chlo

roet

hene

1,4-

Dichlo

roben

zene

Dibro

moch

loro

met

hane

Met

hyl te

rt-buty

l eth

er

Tribro

mom

ethan

e0

10

20

30

40

50

60

70

80

Perc

ent o

f Sa

mpl

es

20

12

123 3

1 1 1 1

VOC’s9 detections for 88 compounds analyzed

0.01

0.1

1

10

Conc

entr

ation

in

Mic

rogr

ams

per L

iter


MCL100

VOC concentrations


Summary 29 wells sampled in urban/commercial areas of

Mobile, Alabama. Field parameters consistent with recently recharged

groundwater. Nutrients similar to earlier study in Montgomery,

Alabama. 22 Pesticides detected. 9 VOC’s detected.

Montgomery Urban Land Use Study

Full network being resampled this water year.

Six sites have been sampled biannually since 2000.

Occurrence of Pesticides in GW in Areas of Intense Row Crop Production

Purpose and Scope Multi-year study – initial sampling in FY09 Evaluate trends in detection frequencies and

concentrations of pesticides in GW near areas of high-intensity row crop production.

Sample 15 wells in three areas of state.

• Northern Alabama

• Southeast Alabama

• Baldwin County Samples analyzed for temperature, specific

conductance, DO, pH, and pesticides.

Questions??

Annual Data Reports http://wdr.water.usgs.gov/

Alabama WSC Web Addresshttp://al.water.usgs.gov

Richard MorelandUSGS Alabama Water Science Center

[email protected]

Documents

Groundwater Quality Beneath an Area of Urban Residential and Commercial Land Use, Mobile, Alabama 2011 2012 Alabama Water Resources Conference September