Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark...
Transcript of Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark...
![Page 1: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/1.jpg)
Using GIS to Predict Arsenic Over 10 ppb in Drinking Water
OrHow to lie with statistics and maps
Rich SouleMDH
![Page 2: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/2.jpg)
![Page 3: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/3.jpg)
![Page 4: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/4.jpg)
![Page 5: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/5.jpg)
All Blue
All Red
Michael Gastner, Cosma Shalizi, and Mark Newman University of Michigan
![Page 6: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/6.jpg)
Michael Gastner, Cosma Shalizi, and Mark Newman University of Michigan
![Page 7: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/7.jpg)
Make a Statewide Map of Arsenic in Groundwater in Less Than 3 Hours
1) Come up with a single physical process.It must be mapped at state scale.
2) Find the data sets representing this process and arsenic.
Evaluate data set bias.3) Generate a Probability Map for Arsenic
over 10 ppb.
![Page 8: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/8.jpg)
Clay
Sand
Sand withIron
ReducedBlack, green and grey
Rotten eggs odor.
Red, brown and, tanLittle to no odor.
Deep
Shallow Oxygen+
Carbon+
MicrobesHAsO4HAsO4--22
HAsO4HAsO4--22
As+5
HAsO4-2
As+3
H2AsO3 Ars
enic
Confining Thickness
HydrogeologicModel
Ars
enic
Time
BiologicalModel
GeochemicalModel
Oxidized
![Page 9: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/9.jpg)
Conceptual Model• Pr(As) > 10 ppb ≈ Clay Thickness.
• Groundwater is reduced by microbes at a constant rate and is limited by electron acceptors (O2, FeNO3, Fe ).
• The flow of electron acceptors is determined by vertical groundwater recharge. – Q=KiA, Assume average “K” and “i” .
• Assume Steady State.
![Page 10: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/10.jpg)
Why?: Spatial RelationshipsArsenic & DM Lobe Wood & DM Lobe
Arsenic >10 ppbArsenic <10 ppb
![Page 11: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/11.jpg)
Data Sets: Geology (CWI)VerifiedLocations
RawLocations
170,000Wells
200,000Wells
Use it All.
![Page 12: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/12.jpg)
VerifiedLocations
RawLocations
Bias: Well Density
![Page 13: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/13.jpg)
Summarizing Well Logs
37 ft
56 ft
21 ft
15 ft
Clay Thickness
+Total 138 ft
Clay
Clay
Clay
Clay
Do this370,000 Times.Takes 20 min.
![Page 14: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/14.jpg)
5 kmGrid
10 kmGrid
Grid Clay Thickness
> 100 Ft.
None
Clay Thickness
![Page 15: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/15.jpg)
Grid Clay Thickness
1 kmGrid
1 kmGrid with Brakes
> 100 Ft.
None
Clay Thickness
No Data
![Page 16: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/16.jpg)
MARSAreaLooks Really Bad….Population Declining….Co-incidence?
![Page 17: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/17.jpg)
Data Sets: Arsenic
Yes
No
Yes
Location
High As?Deeper?
YesWest Central
MARS
State
State
Area
No
Yes
Geology Bias Data
No LocationShallower?
Construction?
CDC/MDH
Deeper?Construction?
GWMAPS
![Page 18: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/18.jpg)
Use MARS Data?
Over 10 ppbNumber in AreaData Set
49%47CDC48%50GWMAPS52%893MARS
Yes, but cautiously.
![Page 19: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/19.jpg)
Get Clay Grid Values
![Page 20: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/20.jpg)
10
%
%
![Page 21: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/21.jpg)
0 20 40 60 80 100Avg. Feet Clay Above Screen
0
20
40
60
80
Pr (
As>
10)
Probability As >10 ppb All Arsenic Data
All Data
MARS Data
GWMAPS
CDC Data
![Page 22: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/22.jpg)
Low
Medium
High
Medium
0 20 40 60 80 100Avg. Feet Clay Above Screen
0
20
40
60
80
Pr(
As>
10)
Mapping Arsenic Using “Blocks”
All Data
MARS Data
GWMAPS
CDC Data
![Page 23: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/23.jpg)
Results
10 ppb
![Page 24: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/24.jpg)
Results
10 ppb
![Page 25: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/25.jpg)
Low
Medium
High
Medium
Score Card
0 20 40 60 80 100Avg. Feet Clay Above Screen
0
20
40
60
80
Pr(
As>
10)
MARS
All
MARS
MARS
MARS
All
AllAll
GWMAPS
GWMAPS
GWMAPS
GWMAPS
CDC
CDC
CDC CDC
![Page 26: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/26.jpg)
Implications• State Scale: the proposed processes may impact
the arsenic concentration in groundwater.• County Scale: These processes are probably
variable (i.e. K, infiltration…).• Section Scale: The change of the redox state of
groundwater through time may be the most important factor.
![Page 27: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/27.jpg)
![Page 28: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/28.jpg)
![Page 29: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/29.jpg)
MPCA & others
![Page 30: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/30.jpg)
Changing the Redox StateBorehole Chemistry & Microbial Ecosystems
“Reducing Factors” Increase Arsenic:Decreasing Infiltration (Tile Drains)Increasing Carbon Load (Monoculture)
“Oxidizing Factors” Decrease Arsenic:Increased Nitrate Loading
![Page 31: Using GIS to Predict Arsenic Over 10 ppb in Drinking WaterMichael Gastner, Cosma Shalizi, and Mark Newman University of Michigan. Make a Statewide Map of Arsenic in Groundwater in](https://reader036.fdocuments.us/reader036/viewer/2022071402/60f049d7872c4a352a66e709/html5/thumbnails/31.jpg)
Acknowledgements• Arsenic Lunch Group:
Mindy Erickson Randal BarnesRoman Kanivetsky Karla PetersonDavid Rindal Mike Berndt
• MDHBruce Olsen Sheila GrowBrian Johnson Justin BlumAl Epp Mike Baker