soil amendments for removing phosphorus, metals, and hydrocarbons
DESCRIPTION
Soil Amendments for Removing Phosphorus, Metals, and Hydrocarbons. Andy Erickson, Research Fellow St. Anthony Falls Laboratory April 1, 2014. Acknowledgements. Collaborators: John S. Gulliver ( UMN ) Peter T. Weiss (Valparaiso University) Multidisciplinary Technical Advisory Committee - PowerPoint PPT PresentationTRANSCRIPT
Soil Amendments for Removing Phosphorus, Metals, and Hydrocarbons
Andy Erickson, Research FellowSt. Anthony Falls LaboratoryApril 1, 2014
http://stormwater.safl.umn.edu/
Acknowledgements• Collaborators:
– John S. Gulliver (UMN)– Peter T. Weiss (Valparaiso University)– Multidisciplinary Technical Advisory Committee
• Partners:– UMN, LRRB, EPA/MPCA, CWL, BWSR,
RWMWD, City of Prior Lake, PLSLWD, Scott WMO, Carver County, Dakota County, Wright County, VLAWMO, CLFLWD, CRWD, and others!
http://stormwater.safl.umn.edu/
What’s in Urban Stormwater?• Solids
– inorganic, organic• Nutrients
– nitrogen, phosphorus, etc. • Metals
– copper, cadmium, zinc, etc.• Deicing Agents
– chloride, salts, etc.• Hydrocarbons• Bacteria/Pathogens• Others
http://stormwater.safl.umn.edu/
How do Soil Amendments Improve Water Quality?
• Better infiltration results in more water treated (less overflow)
• Better filtration results in more particles captured
Physical
• Sorption or precipitation to bind dissolved pollutantsChemical
• Vegetation uptake to capture or bacterial degradation to transform pollutants
Biological
http://stormwater.safl.umn.edu/
Phosphorus Sorption with Iron
• Sand Filtration– Particulate capture > 80%
• Enhanced Sand Filtration – Steel wool increases dissolved phosphorus
capture via surface sorption to iron oxide
Photo Courtesy: A. Erickson
Source: Erickson, A.J., Gulliver, J.S. and Weiss, P.T. (2007) Enhanced sand filtration for storm water phosphorus removal. Journal of Environmental Engineering-ASCE 133(5), 485-497.
http://stormwater.safl.umn.edu/
18.4%
78.6%88.3%
0
100
200
300
400
Diss
olve
d Ph
osph
orus
Co
ncen
trati
on (m
g/L)
Influent 100% Sand 0.3% iron 2% iron 5% iron
Experimental Results(Iron Enhanced Sand Filtration, SAFL)
Detection limit
n = 112 n = 336 n = 336n = 336 n = 112
http://stormwater.safl.umn.edu/
Iron Enhanced Filter (5% iron filings, Maplewood, MN)
Photo Courtesy: A. Erickson
http://stormwater.safl.umn.edu/
MN (Iron Enhanced) Filter(5% iron filings, Maplewood, MN)
Photo Courtesy: A. Erickson
2009-2011 Monitoring Data Total P Dissolved PAverage Inflow (μg/L, ppb) 111 16Average Outflow (μg/L, ppb) 29 11Percent of samples below detection (10 μg/L, ppb)
6% 70%
http://stormwater.safl.umn.edu/
Photos Courtesy: A. Erickson
Iron Enhanced Filter Trenches wet detention ponds (Prior Lake, MN)
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Filter Trenches around wet detention ponds (Prior Lake, MN)
Normal Water Surface
Elevation
Drain tile Iron Enhanced Filter
Water Level Control Weir
Overflow Grate
Drain tile
Volume Treated by Trenches
(Filter Volume)
http://stormwater.safl.umn.edu/
2010 Testing Data:Average Inflow Phosphate = 69.7 μg/L (ppb)
Average Outflow Phosphate = 18.7 μg/L (ppb)Average Reduction = 73.1%
Photos Courtesy: A. Erickson
MN Filter Trenches wet detention ponds (Prior Lake, MN)
http://stormwater.safl.umn.edu/
MN Filter Trenches (Prior Lake MN)
Photo Courtesy: A. Erickson
MN Filter Bioretention (Carver County, MN)
MN Filter Weir (Vadnais Heights, MN)
Photo Courtesy: W. Forbord
Photo Courtesy: VLAWMO and EOR
MN Filter Bioretention (Maplewood, MN)
Photo Courtesy: Barr Engineering Company
http://stormwater.safl.umn.edu/
Designing for Phosphorus Capture with Iron
• As iron rusts, sorption sites for phosphorus are created, therefore:– Design Iron Enhanced Filter systems for watersheds
with significant dissolved phosphorus fraction
– Ensure the system is oxygenated to ensure iron oxides remain aerobic
– Design systems with 8% or less iron by weight to prevent clogging
http://stormwater.safl.umn.edu/
Metals sorption to Compost
Source: Morgan, J. G., Paus, K. A., Hozalski, R. M., and Gulliver , J. S. (2011). "Sorption and Release of Dissolved Pollutants Via Bioretention Media." Project Report 559. St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN.
http://stormwater.safl.umn.edu/
Expected Lifespan (Zinc at 10%)
Source: Morgan, J. G., Paus, K. A., Hozalski, R. M., and Gulliver , J. S. (2011). "Sorption and Release of Dissolved Pollutants Via Bioretention Media." Project Report 559. St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN.
Longer for Cadmium
12 inches
http://stormwater.safl.umn.edu/
Rain gardens sustainably treat petroleum hydrocarbons in stormwater
• Petroleum Hydrocarbons are captured by sorption to organic matter
• Biodegradation prevents accumulation of petroleum hydrocarbons
Source: LeFevre, G.H., Hozalski, R.M., and Novak, P.J. (2012). "The Role of Biodegradation in Limiting the Accumulation of Petroleum Hydrocarbons in Raingarden Soils." Water Research, 46(20), 6753–6762.
http://stormwater.safl.umn.edu/
Phosphorus Leaching from Compost
Source: Morgan, J. G., Paus, K. A., Hozalski, R. M., and Gulliver , J. S. (2011). "Sorption and Release of Dissolved Pollutants Via Bioretention Media." Project Report 559. St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN.
http://stormwater.safl.umn.edu/
Other Amendments
• Alum (water treatment residual) & Hardwood Bark Mulch – Phosphorus sorption (A. Davis, Univ. of Maryland)
• Commercial products (various)• Internal Submerged Zone for
denitrification (W. Hunt, North Carolina State University)
http://stormwater.safl.umn.edu/
Conclusions• Dissolved Stormwater Pollutants are important
– Approx. 45% of total concentration is dissolved• Physical methods are not enough
– Chemical and biological mechanisms can be used to capture dissolved fractions
• There are field-tested solutions!– Minnesota Filter (iron-enhanced sand)
phosphorus– Compost-amended bioretention metals &
petroleum hydrocarbons
http://stormwater.safl.umn.edu/
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Thank you for your attention!Questions?
Photo Courtesy: A. Erickson
For more information, contact: Andy Erickson ([email protected])