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The impact of dairy farms on groundwater quality in Israel’s
Coastal AquiferShahar Baram
Zuckerberg Institute for Water ResearchBen Gurion University of the Negev
The presented study is part of the requirementsThe presented study is part of the requirements for the completion of a Ph.D. degree at
The Ben-Gurion University of the NegevThe Ben Gurion University of the NegevIsrael
Supervisors:Ofer Dahan, BGU Zeev Ronen BGUZeev Ronen, BGU
Daniel Kurtzman, The Volcani Center
Funding:Israel Water Authority
700
Degradation in groundwater quality - Israel's Coastal Aquifer
500
(mg/
L)
100
300Cl
60
1966 1975 1984 1993 2002 Possible causes:
1. Mixture with deep
40
60
mg/
L)
brines
2. Industrial activity
20NO
3-(
3. Intensive agricultural activity
01966 1975 1984 1993 2002
Dairy farming in Israel
Number of cows350,000 heads
Haifa
Total slurry generated ~5 million ton / yearTel-Aviv
No waste treatment proceduresDea
d S
ea
Ashdod
Gaza
Cows1-2001-200201-500501-10001001-2500
The reform in Israel’s dairy farming 1999 - 2006
The “detached” dairy farm concept
• Prevention of rain water and local runoff from entering the sheds
• Prevention of effluent overflows from reaching the environment
• Prevention of effluents from infiltrating into the environment
• Providing an end solution to the effluents (waste treatment plants, power plants etc.)
Before After
The objective of the study:
To evaluate the impact that dairy farm waste lagoons h d t lit i I l’ C t l A ifhave on groundwater quality in Israel’s Coastal Aquifer
Research site
HaifaCowshed drainage
Overflow channel
Tel-Aviv
drainage
Dea
d S
ea
Ashdod
Gaza
Waste lagoon
Cows1-200
Waste lagoon
1-200201-500501-10001001-2500
0Methods
Lithological cross sectionXXXX
10
5Lithological cross section
Sediment sampling, aste ater samplingX
X
XXX
10
15
Groundw
a
wastewater sampling, groundwater monitoring
X
X
20
ater observ
Vadose zone monitoringX
30
25ation w
ellX
30
45Sandy loamClay (38% Montmorillonite)Waste water
X
X
50Sandy loamCalcareous sandstone
In-situ monitoring of the vadose zone
Water content measurement using FTDR
Pore-water sampling using vadose zoneusing vadose zone sampling ports (VSP)
Initial results:
Testosterone and Estrogen in the vadose zoneTestosterone and Estrogen in the vadose zone
Testosterone and Estrogen (µg/Kg dry soil)g (µg g dry soil)
0.00 0.05 0.10 0.15 0.20 0.25 0.300
m)
10
20D
epth
(m20
30
40 TestosteroneEstrogenDetection limtGroundwater Table
Modified from Arnon et al., 2008
50
Monitoring set-up
Waste channelWaste channel Waste Lagoon
Changes in the water content across the vadose zoneWaste channel
θ ~55%
Waste channel marginsg
θ ~35%
Changes in the water content across the vadose zone
θ ~40%
Chloride in pore water across the vadose zone
Chloride in pore water across the vadose zoneWaste channelWaste lagoon
%0%
θ~4
5
θ~5
5%
θ~3
0%θ~4
0
θ
Chloride concentrations in the clayey vadose zone increase with depth
Chloride concentrations in the Groundwater ~800 mg/L
Desiccation cracks at the research site
Conceptual model: the effect of the margins on the pore water dissolved salts concentration
Ammonium in pore water across the vadose zone
Groundwater table
Waste channelWaste lagoonNitrate in pore water across the vadose zone
%%
θ~4
5%
~55%
~30%θ~4
0%
θθ
Nitrate concentration in the recharging solutions ~450 mg/L
Nitrate concentrations in the Groundwater ~300 mg/L
Conceptual model: The fate of nitrogen in the vadose zone
Waste lagoon
First stage:
Fast infiltration
Second stage:Partial sealing of the l
Third stage:Substantial decrease in th t t t d Water content = saturationWater content < saturationWater content << saturationFast infiltrationSaturation of the uppermost sediment
lagoonthe water content and formation of desiccation cracks
Water content saturationOxygen concentration = 0Dominant nitrogen form AmmoniumOxygen concentration > 0Ammonium Nitrate DenitrificationDominant nitrogen form Nitrate
Water content saturationOxygen concentration >> 0Dominant nitrogen form Nitrate
Dominant nitrogen form Nitrate
Conclusions:
• Unlined waste lagoons are point sources for nitrate and salts contamination
• The margins of unlined waste lagoon have a majorThe margins of unlined waste lagoon have a major impact on the overall pollution potential of the lagoon
• Preferential flow in seasonal desiccation cracks may transport pollutants directly to the deep vadose zonetransport pollutants directly to the deep vadose zone, bypassing the biogeochemical active zone of the clay sediment
• Nitrification is likely to accrue under all waste lagoons since the vadose zone is unsaturated
• The fate of nitrate in the vadose zone is water contentThe fate of nitrate in the vadose zone is water content dependent
• Drying of waste lagoon in clayey sediments may accelerate the transport of contaminants in to the deepaccelerate the transport of contaminants in to the deep vadose zone and groundwater
Key consequences following this work
• The vadose zone monitoring system is a useful tool for early detection of pollutants in the vadose zoneearly detection of pollutants in the vadose zone
• Drying of waste lagoon in clayey sediments may accelerate the transport of contaminants into the deep
d d d tvadose zone and groundwater• Assessment of the pollution potential of waste lagoons
must take in to account the effects of the margins• Unlined/earth-lined waste lagoons are point sources for
nitrate, salts and hormones
Thanks:Israel's Water Authorityy
Ms Sara Elchanani
Dr Irena PankratovDr. Irena Pankratov
Ben-Gurion University
GDr. Amit Gross
Dr. Shai Arnon
Mr. Yuval Shani
Mr. Michael Kugel
Local runoff
Concentrations in the local runoff:Total nitrogen forms – 139 ± 207 mg/L (n=69)
Chloride – 65 ± 80 mg/L (n=72)