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“ Napoleon's hair and old lace: proactive water management ”. Patrick Louchouarn Columbia University - MPA ESSPM. “ How is it possible to find meaning in a finite world, given my waist and shirt size? ” Woody Allen. Outline.
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“Napoleon's hair and old lace: proactive water management” Patrick Louchouarn Columbia University - MPA ESSPM “How is it possible to find meaning in a finite world, given my waist and shirt size?” Woody Allen
Outline • Arsenic: From South Texas to Central Arizona (a case for water management) • Identification of metal sources to surface water systems • Long term metal cycling • What’s cooking…
Napoleon’s hair and an old lace… “The level of arsenic found in Napoleon's hair is higher than 10-40 times the normal amounts and is an unmistakable sign of poisoning” Pascal Kintz, Strasbourg Forensic Institute
Arsenic in Bangladesh Drinking Water It’s pretty bad…... “If I die, I will die, but I will not fetch water from another man’s house” Bangladeshi villager
Arsenic in Bangladesh • 95% people use groundwater as drinking source from alluvial and deltaic aquifers • “Naturally” occurring Arsenic contamination • ~ 175, 000 people suffer from chronic As poisoning
Arsenic in Texas Drinking Water It’s not so bad…... “If it donna kill ya, it probably ain’t bad for ya” Texas villager
Finalized EPA Drinking Standard for Arsenic • The Safe Drinking Water Act, as amended in 1996, requires EPA to revise the existing drinking water standard for arsenic. • EPA reduced the maximum level of arsenic allowed in drinking water that reduces the maximum level allowed from 50 parts per billion (ppb) to 10 ppb. This has been challenged by the Bush Administration • New standard will be applied to all community water systems (serving 254 million people) • 12% of these systems will likely have to take corrective action • Estimated National Cost: 3 ppb = 645 M$, 5 ppb = 379 M$ 10 ppb = 166 M$, 20 ppb = 65 M$ Fallonites, Don Cooper, 82, and wife Norma, 81, raise a toast to Nevada's arsenic-rich homebrew on the outskirts of town. Concentrations in drinking water are approximaately 100 ppb. Outside magazine, February 2001
Data map: 31,350 ground-water arsenic samples collected in 1973-2001 Ryker, S.J., Nov. 2001, Mapping arsenic in groundwater: Geotimes v.46 no.11, p.34-36.
Arsenicin Texas Groundwater TWDB and NURE Data Sets
Molybdenumin Texas Groundwater TWDB and NURE Data Sets
Geogenic Source of Metals Catahoula formation, an oxidized volcanic ash is a source of U, As, Mo and other trace metals
Chromatographic Separation Regionally Reduced Oxidized Se U Mo As Adopted from Devoto (1978)
Texas’ Uranium History • “Oxidized” uranium ores were open-pit mined from sandstone-hosted roll-front deposits (1960 - 1983) • Open pit mining feasible because of shallow depth to ore (<300 feet) and the poorly cemented nature of overburden • Voluminous spoils stockpiled near pits. Two processing mills in western Karnes Co. generated large tailings piles
U Mining in the Nueces and San Antonio River Basin San Antonio River Nueces River
Surface Exposure of Protore Reduced sediments near the uranium ore were enriched in As, Mo, Se and radionuclides. Termed “protore” (proto ore), this material was placed on the top of spoil piles where it was most readily eroded.
Stratigraphic Inversion Oxidized overburden (upper strata) were placed at the bottom of spoil Deeper strata enriched in trace elements was placed on top of spoil.
Eroded Spoil at the Haase Moy Wiatrek Mine Gonzales County
South Texas Ecological Impacts of Metals Arsenic exposure to wildlife at ground water seeps in the Nueces River watershed Molybdenosis in Black Angus Cattle, South Texas
Arsenic in Texas Drinking Water What is the environmental legacy of U mining in South Texas…...
Thermocline • Stratified Water column • Declining DO Lyssy Pond
Lake CC DO Profile Partial stratification in August Virtually homogenous in January and following the episodic mixing event in July
Spatial Distribution of As Arsenic levels elevated above ambient by an order of magnitude, depending on the hydrodynamic regime.
Ground Waters U Std. As Std
“Making prediction is very difficult, especially about the future” – Casey Stengel Water scenarios: Projected and actual global withdrawals. From Gleick (2000): The World’s Water, 2000-2001
“Making predictions…” proposed Aquifer recharge Mary Rhodes pipeline Pass through needs for estuaries Water scenario: Regional management model
Hydrodynamic control: evapoconcentration M/t = CiQi – CQo + Rd – Rp AsL(t) = AsL(t-1) + ([As]iQi) - ([As]Qo) [As](t) = AsL(t)/Vol(t)
Implications of evapoconcentration Water management practices that take into consideration temporal changes (short-scale and short-lived) Management of water resources and overdrawn environments: Owens Lake and Salton Sea (California)
Tucson’s Drinking Water “Access to safe water is a fundamental human need and, therefore, a basic human right. Contaminated water jeopardizes both the physical and social health of all people. It is an affront to human dignity” Kofi Annan – UN Secretary-General on World Water Day
Geochemical controls of As cycling: • Fe/Mn oxyhydroxides
As desorption and dissolution due to changes in reducing conditions
Outlook for As research • Hypothesis 1: The high alkalinity and pH of CAP waters will lead to a rise of these properties in the Tucson recharged aquifer in turn leading to desorption of As (and possibly other oxyanions) from the aquifer’s solid phase. • Hypothesis 2: The incorporation of natural DOM from CAP waters into the aquifer will lead to decreased O2 concentrations and changes in redox potential in these waters thus allowing for the dissolution of Fe/Mn hydroxides and subsequent desorption of oxyanions/anions. • Hypothesis 3: Different areas of Tucson basin contain significantly different concentrations of As and other oxyanions thus leading to unequal exposure potential among specific populations.
