Millenium Development Goals: Progressaquaticpath.phhp.ufl.edu/waterbiology/handouts/Jawitz-Hydrology.pdfwetlands: 0.03% of total on ... • Ratio of void spaces in a geologic formation

2

Millenium Development Goals: Progress

• 2002 World Summit on Sustainable Development (South Africa)– promised to halve the number of people without clean water

and sanitation by 2015• 2003 World Water Summit (Kyoto, Japan)

– same goal reiterated• 2004 UN Commission on Sustainable Development

(New York)– found there had been no progress

• “If the world continues at this snail’s pace, billions of people will remain without access to safe water or basic sanitation, with little prospect of escaping poverty.”– Ravi Narayanan, Water Aid

Pearce, Keepers of the Spring

Water for… revealing the mystery of language and awakening the soul

We walked down the path to the well-house, attracted by the fragrance of the honeysuckle with which it was covered. Some one was drawing water and my teacher placed my hand under the spout.

As the cool stream gushed over one hand she spelled into the other the word water, first slowly, then rapidly. I stood still, my whole attention fixed upon the motions of her fingers.

Suddenly I felt a misty consciousness as of something forgotten — a thrill of returning thought; and somehow the mystery of language was revealed to me.

I knew then that "w-a-t-e-r" meant the wonderful cool something that was flowing over my hand. That living word awakened my soul, gave it light, hope, joy, set it free!– Helen Keller, The Story of My Life (1903)

http://en.wikiquote.org/wiki/Helen_Keller

The water issue today… and yesterday

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Earth systems are often studied as Hydrosphere, Atmosphere, Geosphere, Biosphere

• Hydrosphere physical processes: Physical attributes and processes of the traditional global hydrologic or “water cycle”, including runoff, geomorphology, sediment processes, evapotranspiration, moisture transport, and precipitation. The global water cycle encompasses not only hydrologic processes over and under the land surfaces of the earth, but also in its oceans and atmosphere.

•Hydrosphere biological and biogeochemical components: Includes aquatic and riparian organisms and their associated ecosystems and biodiversity. These organisms are also integral to the geochemical functioning of the global water system and not simply recipients of changes in the physico-chemical system. Hence we also include here the biogeochemistry of the global water system and water quality.

Hydrologic Cycle

USGSwater.usgs.gov/.../htdocs/ natural_processes_of_ground.htm

3

What about humans?

• We left humans out of the Earth systems above (except in the biosphere):

• Human intervention in the hydrologic cycle defines water resources• Corollary to the hydrologic cycle: Hydraulic cycle

• The sum of water-related organizations, engineering works, and water use sectors. Society is not only a component of the global water system but also a significant agent of change within the system. Society is not only exposed to changes in water availability but also takes actions to mitigate or adapt to these changes.

Hydraulic cycle

• Source• Treatment• Distribution• Use• Collection• Treatment• Disposal

Chadwick and Moffett, 1998. Hydraulics in Civil and Environmental Engineering

Water SourceSurface WaterGroundwater

Water Treatment

Withdrawal

Distribution

Water UsePublic, Commercial,

Industrial, Institutional

Wastewater Treatment

WastewaterCollection

Disposal

Fresh Water Withdrawal

• Importance of agricultural use• Regional effects

Fraction of annual

renewable water resources

withdrawn (%)

Domestic Use (%)

Industrial Use (%)

Agricultural Use (%)

World 8 8 23 69 Egypt 97 7 5 88 Libya 404 15 10 75 United States 19 12 46 42

Gleick, 1993 or online version at http://worldwater.org

Earth’s Water Resources

Everything else (2.80%)

Oceans (97.20%)

Hydrosphere

All water in the atmosphere, soil, rivers, lakes, and wetlands: 0.03% of total on Earth.

Groundwater (0.62)

Everything else (0.03)

Glaciers (2.15)

Non-Ocean Components

4

Earth’s Water Resources• All water in the atmosphere, soil, rivers, lakes, and

wetlands: 0.03% of total on Earth.

• 2/3 of freshwater in polar ice caps– Antarctic ice sheet: 80% of the world’s ice– Covers an area almost 1.5 times the U.S. – Sea level would rise about 300 feet if the ice melted

• Groundwater represents 95% of availablefreshwater

The Antarctic ice sheet average thickness is nearly 1 mile

December 1997

http://airsports.fai.org/may98/may9804.html

Glacier Retreat

Rhone Glacier,Switzerland

2001

1930

Gary Braasch

Glacier Retreat

Rhone Glacier,Switzerland

2001Gary Braasch

1859

“shifting baseline syndrome”?Pauly, 1995 (fisheries)

The Global Water System

• Water movement constitutes the largest flow of any material through the biosphere.

• The importance of fresh water, which strongly regulates productivity and supports ecosystems and biodiversity, is evident throughout the biosphere.

• Fresh water is also critical to human society.– underpins global food production: irrigation, livestock, fisheries, and

aquaculture– domestic, industrial, hydropower, and recreational water use is crucial

to a large and growing population that aspires to long-term improvements in well-being

• Providing basic sanitation and clean drinking water services remains a major public health challenge. – more than 1 billion people are without access to clean drinking water,

2.5 billion are without sanitation, and over 5,000 people, mostly children, die each day from water-related diarrheal diseases

Vorosmarty et al., 2004. EOS, 85(48), pp. 509, 513-514

Part II: Hydrology

5

Who uses groundwater?

Ref 3.1, Alley, W.M., Reilly, T.E., and O.L. Franke, 1999, Sustainability of Ground-Water Resources. United States Geological Survey Circular 1186, USGS: Denver, CO. http://water.usgs.gov/pubs/circ/circ1186

Why do people use groundwater?

• Local springs• Not enough rainfall• Abundant supply• Water quality

Suwannee River State Park, FLPhoto by me.

Aquifer: n. body of permeable rock able to hold or transmit water [Latin: aqua + fer]

• Confined aquifer – Wedged between layers of relatively impermeable

materials and consequently under pressure.

• Unconfined aquifer – Water table is the upper boundary. Because the aquifer

is not under pressure the water level in a well is the same as the water table outside the well. An unconfined aquifer is near the earth's surface causing it to be easily recharged locally as well as contaminated.

Unconfined vs Confined

• Contamination issues?

Porosity = …

• Ratio of void spaces in a geologic formation to the total volume of the formation.

• Intergranular vs intragranular (also interparticle/intraparticle)

• Primary vs secondary

T

v

VV

=η

Intergranular Porosity

6

Porosity Tidbits

• Water table drop of 10 ft = how much water? – i.e., rainfall deficit

• George Pinder, A Civil Action

Water table = top of the zone of saturation (where pores are saturated with water)

• Relationship between water table and groundwater flow?– Hydraulic gradient (ΔH/Δx): slope of top of water table

• Water pressure is equal to atmospheric pressure• Water table depth fluctuates with climate

conditions on the land surface above and is usuallygently curved and follows a subdued version of the land surface topography.

Dynamics of water table connected to near-surface processes

• Infiltration from surface vs evapotranspiration• Influent vs effluent streams• “saturated zone” is a dynamic definition

Vadosezone

Vadose zone = between ground surface and water table

• Water pressure is less than atmospheric• ‘vadosus’

Permeability, k [L2] = ability of a porous medium to transmit fluids• Function of absolute value of size of pores and

connectivity• Hydraulic Conductivity (K vs k) [LT-1]

– describes the rate at which fluid can move through a permeable medium

• Both porosity and permeability control the rate of groundwater flow along with…

• Driving force…– Hydraulic gradient– Usually gravity

Darcy’s Law

Q/A=K(h/l) Q = Water flow rate (volume/time)

A = Cross-sectional Area

K = hydraulic conductivity

h = height difference

l = Distance traveled

7

Specific discharge (Darcy velocity) not the same as porewater velocity

• Darcy’s Law

• Porewatervelocity (for saturated porous media)

qQA

Kddl

= = −φ

vq

=η

Kk g

=ρμ

But, unsaturated more tricky…

Hydraulic Gradient

• Natural groundwater flow• Groundwater is not sitting still!

– But is moving slowly…– Travel time for 10 m vs 1 km?

Definition of residence time

• The period of time that water remains in a system

τ = V/Q• How long does groundwater spend in an

aquifer• Turnover time is inverse of residence time

Residence Time and Vulnerability• Ocean

– P = 92,000 mi3/yr; Runoff = 10,000 mi3/yr– V = 322,600,000 mi3

– Average residence time = 3,100 years (or total turnover once in that time)

• Similar analysis for GW– P = 27,000 mi3/yr, ET = 17,000 mi3/yr– Roughly estimate that 10,000 mi3 infiltrates– World groundwater reservoir = 2,000,000 mi3– Average residence time = 200 years (or total turnover

once in that time)– Of course not uniform (25,000 yr old water under

Saudi Arabia = Pleistocene ice age)

Residence Time and Vulnerability

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Floridan Aquifer System: Thickness in Feet

8

Hydrogeology of South FloridaWest Palm

BeachLake

OkeechobeeFt. Myers Labelle

2300

2100

1900

1700

1500

1300

1100

900

700

500

300

1000

Water Table Aquifer

Lower Confining Unit

Boulder Zone

Lower Floridan Aquifer

Middle Confining Unit

Upper Floridan Aquifer

Mid Hawthorn Aquifer

Lower Tamiami Aquifer

Biscayne

Sandstone Aquifer

Aquifer

WEST EASTDisposal Disposal WellWell

ASR ASR WellWell

Hawthorn Confining Zone

Discharged to the ground: landapplication systems (drain fields, percolation ponds, sprayfields) and reuse systems

Marella, R.L., 2004, Water withdrawals, use, discharge, and trends in Florida,2000: U.S. Geological Survey Scientific Investigations Report 2004-5151, 136 p.

Florida has 331 first-magnitude springs (out of 78 nationwide)

• First-magnitude springs– Flow > 100 cfs (> 65

MGD)– Biggest? 2

• Upper Floridan –confining unit?

1 2002 revision (classifications have changed since 1970s; karst window vs spring-seep, etc)2 SS 820 cfs (530 MGD)

Silver Springs

Silver River State Park

Hydrograph

Storm Runoff

Rising limb Recession limb

Base flow

Rainfall

Infiltration Excess

http://soilandwater.bee.cornell.edu/research/VSA/processes/processes_infil.html

9

Infiltration Excess

http://soilandwater.bee.cornell.edu/research/VSA/processes/processes_infil.html

Saturation Excess

http://soilandwater.bee.cornell.edu/research/VSA/processes/processes_sat.html

Saturation Excess

http://soilandwater.bee.cornell.edu/research/VSA/processes/processes_sat.html

Undeveloped Watershed

• Pervious surface

• Depressions in landscape

• Vegetated “rough”surface

DryRainEvent

Effect of Development on Storm Hydrograph

Pre-development

Time

Stag

e

Storm Event

Developed Watershed• Impervious surfaces

increase • Depressions in

landscape drained• Vegetated “rough”

surfaces decrease and become smooth with quicker runoff.

• Culverts, swales, and ditches move water off the landscape quickly.

RainEvent

10

Effect of Development on Storm Hydrograph

Pre-development

Post-development

Time

Stag

e

Storm Event

Part III: Groundwater Contamination

Deadliest hurricanes in history

Deadliest Atlantic hurricanes

Hurricane Season Fatalities1 "Great Hurricane" 1780 22,0002 Mitch 1998 11,000 – 18,0003 "Galveston" 1900 8,000 – 12,0004 Fifi 1974 8,000 – 10,0005 "Dominican Republic" 1930 2,000 – 8,0006 Flora 1963 7,186 – 8,0007 "Pointe-a-Pitre" 1776 6,000+8 "Newfoundland" 1775 4,000 – 4,1639 "Okeechobee" 1928 4,075+10 "San Ciriaco" 1899 3,433+

http://www.wunderground.com/hurricane/deadlyworld.asp http://en.wikipedia.org/wiki/List_of_notable_tropical_cyclones

Deadliest hurricanes in history

aftermath and dissatisfaction with response to hurricane led to 1971 civil war and creation of Bangladesh (formerly East Pakistan) – unique for a natural disaster to lead to civil war?http://www.wunderground.com/hurricane/deadlyworld.asp http://en.wikipedia.org/wiki/List_of_notable_tropical_cyclones

The 20 Deadliest Tropical Cyclones in World History

Name / Areas of Largest Loss Year Ocean Area Deaths

1 Great Bhola Cyclone, Bangladesh 1970 Bay of Bengal 550,0002. Hooghly River Cyclone, India and Bangladesh 1737 Bay of Bengal 350,0003. Haiphong Typhoon, Vietnam 1881 West Pacific 300,0003. Coringa, India 1839 Bay of Bengal 300,0005. Backerganj Cyclone, Bangladesh 1584 Bay of Bengal 200,0006. Great Backerganj Cyclone, Bangladesh 1876 Bay of Bengal 200,0007. Chittagong, Bangladesh 1897 Bay of Bengal 175,0008. Super Typhoon Nina, China 1975 West Pacific 171,0009. Cyclone 02B, Bangladesh 1991 Bay of Bengal 140,00010 Great Bombay Cyclone, India 1882 Arabian Sea 100,000

Death counts from large killer cyclones are highly uncertain, particulary for those before 1900. The above rankings are somewhat speculative. Information sources: Banglapedia, Wikipedia, and Encyclopedia of Hurricanes, Typhoons, and Cyclones (1999), by David Longshore.

Risk Assessment: Three components

• Contaminant Source– site characterization

• Transport – site characterization/transport processes -> model

• Receptor– Exposure pathways -> water and soil standards

Part III: Groundwater Contamination

Contaminant source

11

Sources of groundwater contamination

• Point source – Gas station– Dry cleaner– Landfill– Deep-well injection– Other spills and disposal sites

• Nonpoint source– Agriculture– Wastewater

• Leaky sewers• Septic tanks

– Other wide-area sprays… (mosquito control; Goshutes)

Point source

Agricultural surface water drainage in the Everglades Agricultural Area (EAA) –nutrients (C, N, P), pesticides (photo from SFWMD)

Non-point source

In July 1945, DDT was widely (and mistakenly) hailed as a progressive measure to eradicate disease-bearing mosquitoes without posing a risk to human health. In this photo from a beach on Long Island, New York, a new insecticide-spraying machine is tested as beachgoers play in the mist. Although this chemical contact is obvious, many other sources of environmental chemical exposure are more difficult to identify.

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DDTPowerful InsecticideHarmless to Humans

Applied byTODD Insect Fog Applicator

Groundwater Contaminants

• Solutes– Organic– Inorganic

• salt

• Others?– Sediment– Biological (bacteria, viruses)

Contaminant Source Zone• Nonaqueous phase liquid (NAPL) contamination of groundwater

– immiscible with water – but enough dissolves to contaminate

DNAPL

GW Flow

Residual & Separate Phase Material

12

Part III: Groundwater Contamination

Contaminant transport

Solute Transport in One Slide

• Advection – physical mechanism by which pollutants are transported along with the flow of subsurface water

• Dispersion – spreading caused by ‘differential advection’

• Reactions– Sorption/desorption– Degradation

Dispersion conceptualized as differential advection

Part III: Groundwater Contamination

Receptors and case studies

Chess-based alternatives for dealing with groundwater contamination

• When in check, four alternatives:– Check mate

– Move the king out of check

– Block the attack

– Remove the attacker

Alternate water supply

Source management (Containment)Plume management (PAT)

Source removal

Illinois and Michigan Canal

• Constructed 1836 - 1848 for transportation of goods, 100 miles• 1871 cut deeper to convey wastewater away from Chicago

13

Selected events in the history of Chicago

• 1673 - Louis Joliet and voyageurs• 1848 sugar from New Orleans passed through

I&M Canal• 1849 first of annual cholera outbreaks• 1871 I&M Canal deepened and Chicago River flow

reversed for wastewater• 1900 Chicago Sanitary and Ship Canal• 1922 Cal-Sag Canal (the third major canal)• 1933 Illinois Waterway Channelized

What is cholera?

• Acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae.

• The infection is often mild or without symptoms, but sometimes it can be severe.

• Approximately one in 20 infected persons has severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps.

• In these persons, rapid loss of body fluids leads to dehydration and shock.

• Without treatment, death can occur within hours.

http://www.cdc.gov/ncidod/dbmd/diseaseinfo/cholera_g.htmhttp://www.cdc.gov/ncidod/dbmd/diseaseinfo/cholera_g.htm

The Hall of Forgotten Presidents

• James K. Polk, President 1845 - 1849• “President Polk worked extremely hard during his

term and at the end of it, suffering from exhaustion, decided to return to private life even though he remained popular and probably could have won a second term. He also felt he had achieved what he had set out to do, and simply didn't need to return to the office. At the age of only 53, he died at his Nashville home a mere three months after leaving office.”

http://www.paulsilhan.com/hallpres.htmhttp://www.paulsilhan.com/hallpres.htm

Cholera epidemic origins in early 1800s• 1816-1826 - First pandemic: Previously restricted, the pandemic began in

Bengal, then spread across India by 1820. It extended as far as China and the Caspian Sea before receding.

• 1829-1851 - Second pandemic reached Europe– London in 1832 - at least 3000 victims– Also in 1832 Russia, Quebec, New York– By 1834, the Pacific coast of North America

• 1849 - An outbreak in North America took the life of U.S. President James K. Polk

• 1852-1860 - Third pandemic mainly affected Russia, with over a million deaths.• 1863-1875 - Fourth pandemic spread mostly in Europe and Africa.• 1866 - Outbreak in North America.• 1899-1923 - Sixth pandemic had little effect in Europe because of advances in

public health, but Russia was badly affected again.• 1961-1970s - Seventh pandemic began in Indonesia, called El Tor after the

strain, and reached Bangladesh in 1963, India in 1964, and the USSR in 1966. From North Africa it spread into Italy by 1973. In the late 1970s there were small outbreaks in Japan and in the South Pacific.

• January 1991 to September 1994 - Outbreak in South America, apparently initiated by discharged ballast water. Beginning in Peru there were 1.04 million identified cases and almost 10,000 deaths.

http://en.wikipedia.org/wiki/Cholerahttp://en.wikipedia.org/wiki/Cholera

Cholera today

• Developing world • WHO alerts (screen

capture from January 2006)

http://www.ph.ucla.edu/epi/snow/snowpub.html

Dr. John SnowSoho, London

1854860 cholera deaths

14

Data map(see Edward Tufte)

www.nationalgeographic.com www.nationalgeographic.com

Plaque photo byJohn White, May 2004

By the 1880s, Chicago's sewage flowed from the Chicago River past the Two Mile Crib, the source of Chicago's drinking water in Lake Michigan. Epidemics of typhoid and other diseases led to the establishment, in 1889, of the Sanitary District of Chicago (nowMetropolitan Water Reclamation District).

While the Sanitary and Ship Canal resulted in 91% drop in the rate of typhoid deaths in Chicago by 1908, Chicago's water supply was not truly safe until the addition of chlorine to the water in 1912. By 1917 Chicago's typhoid death rate had fallen to lowest of any major city in the nation.

Chicago Public Libraryhttp://www.chipublib.org/digital/sewers/history4.html

1995 Motor vehicle accident deaths17 per 100,000

15

World Human Population Growth West Bengal/Bangladesh

• About 10% of global population lives in the Ganges-Brahmaputra delta

• Sediments carried by the rivers transformed the landscape to one of the most fertile lands of the world

Arsenic in Groundwater• What is the source?• What are the pathways?• What is the remedy?

http://international.usgs.gov/projects/bg_arsenic.htm

Woburn, MA• Leukemia cluster• People did not realize the water

was contaminated

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A personal history of encounters with DNAPL doubters

1995 – Can’t find it

• and even if you could, can’t remove it1998

– Ok, maybe you can remove it– but still can’t find it

• and even if you could, too expensive2001

– Ok, maybe you can find it and even remove (most of) it

– but no benefit from partial source removal• and even if there was some benefit, it’s not

enough to reach MCL2005

– hmm, maybe you can find it, remove it, and even accrue benefits

• but back-diffusion will kill you

Hill AFB 1994-1996; Dover AFB 1997-1999Rao et al. (WRR, 1997); Jawitz et al. (EST, 1998); McCray and Brusseau (EST, 1998); Faltaet al. (WRR, 1999); Brooks et al. (JCH, 2004); Childs et al. (JCH, 2006)

Sages (FL) 1998; Bachman Road (MI) 2000Jawitz et al. (EST, 2000); Mravik et al.(EST, 2003); Ramsburg et al. (EST, 2005)

Partial source removal debate: TheorySale and McWhorter (WRR, 2001); Raoand Jawitz (WRR, 2003); Parker and Park (WRR, 2004); Jawitz et al. (WRR, 2005)

Partial source removal and flux: Lab and field dataFure et al. (JCH, 2006)Brooks et al. (in prep)

WRR = Water Resources Research; EST = Environmental Science & Technology; JCH = J. Contaminant Hydrology

Historical summary related to present and future trends

• In summary– What was once scoffed at as unreasonable, too extreme, too

expensive is now recognized as necessary (although perhaps not quite “standard”)

– Practitioner community has caught up with research community on many fronts

• Current research says extensive characterization provides best chance of remedial success– But still many projects underspend on characterization– Investment in characterization predicted to grow

substantially

In situ flushing source zone remediation: Injection and extraction of chemical additives to solubilize(or mobilize) NAPLs from the subsurface

GW Flow

Injection WellRecoveryWell

2 PV 4 PV1 PV 9 PV6 PV

Jawitz et al., 1998. ES&T, 32(4).

Mass Reduction: SPME at Hill AFB

Triangles (red) = PCESquares (blue) = Ethanol

0

40

80

120

160

200

PCE

(mg/

L)

0

4

8

12

16

20

Etha

nol (

%)

0 5 10 15 20 25 30 35 0

200

400

600

800

1000

1200

PCE

(mg/

L)

0

20

40

60

Etha

nol (

%)

0 10 20 30 40 50 0

100

200

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500

PCE

(mg/

L)

0

10

20

30

40

50

Etha

nol (

%)

0 10 20 30 40 50 60

0

2

4

6

8

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PCE

(mg/

L)

0

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Etha

nol (

%)

0 10 20 30 40 0

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PCE

(mg/

L)

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Etha

nol (

%)

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1400

PCE

(mg/

L)

0

5

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25

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Etha

nol (

%)

0 20 40 60 80 100

RW 2 RW 3 RW 4

RW 5 RW 6 RW 7

Volume (kL)

Mass Reduction: Jacksonville, FL Site

Jawitz et al., 2000. ES&T, 34(17).

17

Remediation Performance Evaluation: Mass Removal

Hill AFB cosolvents (1994-1995) ~82%Hill AFB microemulsions (1996) ~90%CFB Borden cosolvents (1997) ~70%Dry cleaner site, Jacksonville, FL (1998) ~64%Dover AFB cosolvents (1998-1999) ~62%Dover AFB surfactants (2000) ~68%

Fraction of mass removed

Contaminant flux = f (HS, DS)HS - hydrodynamic structureDS – DNAPL architecture

Most contaminated

Least contaminated

ContaminantFlux (Jc)

ControlPlane

ContaminantFlux (Jc)

ControlPlane

B’

Source Zone B

A’

A

Post-Remediation:Source Zone

Pre-Remediation:

B

A’

A

B’

Source, Plume, Compliance PlanePre-Remediation:

DissolvedPlume

Control Plane Compliance Plane

DNAPL SourceZone

Dissolved

Partial Mass Removal + Enhanced Natural Attenuation:DNAPL SourceZone

Control Plane Compliance Plane

Plume

Dissolved

Partial Mass Removal:

DNAPL SourceZone

Control Plane Compliance Plane

Plume

Groundwater Protection Zone

(Wellhead protection)

Nitrate contaminants stored in the subsurface

• Potential long-term internal load

• McMahon et al., 2006 WRR