August 23, 2011

Gypsum Use in Agriculture: Impact on the Environment Dr. Darrell Norton

USDA-ARS, National Soil Erosion Research Laboratory Purdue University [email protected]

John A. Andersen, Jr. Greenleaf Advisors

[email protected]

Global Environmental Stresses: Soil Degradation • Depleted soils threaten economies and human health • Water and food security issues • 23% of global disease attributable to environment • 13 million annual deaths from environmental causes can be prevented (WHO)

Environmental Benefits of Gypsum

Water Conservation

Water Quality

Greenhouse Gas Sequestration

Gypsum

Reduced Toxicity

Enhanced Crop Yields

Soil Nutrient Retention

Surface Sealing inhibits penetration of water and oxygen into soils

• Rainwater: Naturally distilled and low in electrolytes • Physical and chemical processes occur at raindrop impact • These processes lead to surface sealing

Many Soils Are Degraded

Healthy Soil

Degraded Soil

Effect of Degradation by Erosion on Crop Productivity

Soil Nutrient Retention: Seedling Emergence Improves With Gypsum

Treated

Not treated

Soil Nutrient Retention: Agricultural Yields Increased with Gypsum Treatment

Treated

Not treated

B/A

Treated

1-40 41-80 81-120 121-160 161-200 N W 0.1

0

0.1

0.2

Miles

Corn Yields, 1T/A Gypsum (1997)

E S

Not treated

Nutrient Loading Contributes to Hypoxic And Anoxic Zones

Hypoxic zones in the Great Lakes

Dead zone: Gulf of Mexico (Approximately the size of New Jersey)

Sediment Loading from Maumee River Basin to Western Lake Erie

Friday, March 13, 2009 3 Days After Storm

Sediment Loading from Lower Fox River Watershed into Green Bay 0.90% 1.70%

5.00% Agriculture

Urban (regulated) 22.30%

0.80% 3.20%

General Permits Urban (nonregulated) Agriculture 65.80%

Municipal WWTFs Urban (regulated MS4) Industrial WWTFs Construction Natural Background

0.40%

Sources of baseline TSS loading in the LFR Basin. The Cadmus Group

Nutrient Runoff Causes Algae Blooms

Don’t Be Depressed We Can Do Something About Erosion And Runoff

Gypsum Reduces Detachment of Sediment and Loss to Runoff

Treated vs Not treated

0.40

80.00

0.30

60.00

0.20

40.00

0.10

20.00

0.00

0.00 5 10 5 20

30

40

Duration [min]

50

60

mm/h

soil loss [g/m^2*s]

Runoff Pace without treatment

soil loss [g/m^2*s]

Runoff Pace with treatment (PAM+FBCBA) 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00

80.00 60.00 40.00 mm/h 20.00 0.00 5 10 15 20 25 30 35 40 45 50 55 60 Duration [min]

Effect of Gypsum on Runoff and Soil Loss 35 30 25 20

Runoff (mm) Soil Loss (g/10 sq m) SRP (mg/sq m)

15 10 5 0 Control

Gypsum

Gypsum Effect On N And P In Manure Rich Soils 14 12 10 SRP (mg/L * 10) TP (mg/L) Nitrate (mg/L) TN (mg/L)

8 6 4 2 0 No-Till Gypsum Manure Man+Gyp

Water Quantity Depletion “Water is the oil of the 21st century” –Andrew Liveris, CEO Dow Chemical

Water Level Decline in The Ogallala Aquifer

 Water use of agriculture o ~ 70% of water use is for agriculture  Water levels are fallings worldwide o Ogallala Aquifer water levels drop 150 feet o Waukesha Aquifer is 600 feet below original level

Severe Cracking Wastes Water Gypsum Reduces Cracking Not Treated

Treated

Water Stress Reduced with Gypsum and PAM

Not treated

Treated

Improved Infiltration/Drainage By Amending Soil with Gypsum

Treated w/ FGD Gypsum

No Treatment

Degraded Soils Increase Greenhouse Gases • Greenhouse gases contribute to climate change • Nitrogen-based fertilizers are energy intensive • Damaged soils process less nitrous oxide (NO2 traps 310 times more heat than CO2)

Marian Koshland Science Museum of the Natural Academy of Sciences

Improved Nitrogen Efficiency

Treated

Not Treated

Increased Root Mass Treated vs. Not treated with Perched Water Table

Natural Toxins and Pathogens Are Present in Soil

•Natural toxins and pathogens occur in geology and soils •Mercury •Arsenic •Bioaccumulation threatens humans

Gypsum Treatment Reduces the Impact of Toxins and Pathogens Toxins are less bio-available to plants with gypsum

Pathogens are neutralized by gypsumenhanced natural plant processes

Healthier food, animals and people

RCRA Total Elements in Materials Added (USEPA 3051) Material

As

Ba

ppm

ppm

Cd

Cr

ppm ppm

Hg ppm

Pb ppm

Se ppm

FGD #1