california state water resources control board
TRANSCRIPT
TypicalTypicalWaterWaterChemistryChemistry
A part per million may be hard to comprehend or visualize. Want to see how much it is?It’s a credit card lying in the middle of a football field.
Want to see what taking in a milligram per kilogram (1 ppm) of your body weight amounts to? It’s the equivalent of 726 people, each weighing 150 pounds, sharing a chocolate bar (~50 grams).
California Water Service Company California Water Service Company 2006 Water Quality Report2006 Water Quality Report
Pollution sources
Shallow groundwater is most at risk
Fig. 19.07 a
Unsaturated zone
Water held in the unsaturated zone is immobile. When it reaches the water table, it can MOVE—carrying contaminants along with it!
Water table
Fig. 19.09
W. W. Norton
Shallow groundwater is more susceptible to pollution. Impermeable layers mayprotect deeper aquifer if they are continuous.
Fig. 19.25 b
W. W. Norton
Fig. 19.25 c
W. W. Norton
Plume will move perpendicular to contour lines on your “topographic map”Of the water table!!!! (Unless it’s fractured bedrock!)
LNAPL—Light Non-Aqueous Phase Liquids—float on water table
DNAPL—Dense Non-Aqueous Phase Liquids—sink through groundwater
Halogenated Organics
The alchemy of contamination. Chromium in the soil of this New Jersey industrial parking lot has dissolved in a pool of standing water. Because chromium can go into solution and move through soil, chromium pools and blooms (the crystallized chromium left on the surface when the water evaporates) may occur some distance from the original site of contamination.
Metals
Metals (like Mercury) and organic chemicals (like PCB’s) are showing up in fish
a) About 10 percent of active California public water-supply wells have nitrate contamination exceeding the drinking water standard of 45 parts per million. In agricultural areas, such as Stanislaus County, up to 80 percent of groundwater is affected or polluted by nitrate. (b) The map shows the extent of nitrate contamination throughout the state.
Nitrates
Occurrence of Arsenic in Groundwater in California
From ACWA Arsenic Study, 2000
Ugandans collecting drinking water
Water with very high counts of E. coli and other deadly bacteria is purified in a few short hours by proper placement in readily available plastic bottles which are left in the sun. Children and caregivers are trained through schools and church teaching programs to use the system, being encouraged and held accountable by trained staff. Case study results have been dramatic. Participating families in our target areas have experienced up to 80% reductions in water borne diseases.
Notice rain watercollection system
Pharmaceuticals
Point Source
Total Maximum Daily Loads (TMDL’s): A TMDL requires that all sources of pollution and all aspects of a watershed's drainage system be reviewed, not just the pollution coming from discrete conveyances (known as point sources), such as a discharge pipe from a factory or a sewage treatment plant.
Much emphasis in the war on NPS pollutants is placed upon education of the public.
RCRA seeks to stop illegal dumping of waste by providing a means of tracking the waste from “cradle to grave”
California Water Service Company California Water Service Company 2006 Water Quality Report2006 Water Quality Report
