Describe the characteristics of ground water
- covers in geological formations and soils beneath water table
- nearly oxygen free
- dissolved ions at their lowest valence
- doesn’t contain particulates
Ground water movement is influenced by?
- gravity
- porosity
- pressure
Darcy’s law
Q=K x ^H x A x T
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Ground water sampling considerations
- aquifer depth
- recharge rate
- soil permeability
- topography
- type of analyte
Analyst must obtain history and Geo of site
Considerations for sampling ground water wells
- purging of stagnant water before sampling
- use of piezometer to measure fluid pressures such as groundwater elevations and pore pressures
Different types of water sources
Surface water-rivers, lakes, runoff, ponds, stream and reservoirs
Ground water- monitoring wells and drinking water
Spring water
Wastewater- landfill leachate, industrial effluent, tailings ponds
Ice
Surface water body classification
Class 1:potable water
Class 2: shellfish propagating and harvesting
Class 3: recreational propagation and maintenance of fish and wildlife
Class 4: agricultural water supply
Class 5: navigation, utility and industrial use
Surface water sampling considerations
Ensure that non-homogenous particles are removed, such as plant matter
Sampling up stream in flowing waterways
Collecting enough sample for QA/QC
Sampling considerations for rivers and streams
- width
- depth
- discharge point
- amount of suspended sediment
- aquatic life present
Sampling from boats of bridges
- take sample on upstream side of bridge or boat
- ensure sample bottle doesn’t touch the river bottom
Factors to consider for river and stream sampling
Access Point of contamination Flow rate Changes in the steam Type of bed, depth and turbulence Structure present Safety
Factors to consider for lake samplin
Access
Spatial stability
Thermal stability
Factors to consider for ground water sampling
Site of contamination
Purification and treatment process
