Air, water, soil, legal, and field sampling Flashcards
Define Groundwater’s properties
- nearly oxygen free
- identified by dissolved ions at their lowest valence level
- Doesn’t contain particulates
Groundwater is influenced by:
Gravity
pressure
porosity
friction
Darcy’s Law describes:
the flow of a body of water through a porous medium, namely that the porous medium will influence how contaminants are transported
Groundwater sampling is affected by:
aquifer depth recharge rate soil permeability topography and type of analyte
Groundwater well sampling requires the purging of well prior to sample collection because:
of stagnant water
Methods and rate of purging, time between purges and sampling, and the sampling itself depend upon…
the well’s diameter, depth and recharge rate
Purge volumes usually range from..
three to ten well volumes
In general, a sample should only be taken after…
In general, a sample should only be taken after
A piezometer is designed to measure
fluid pressures such as groundwater elevations and pore pressures when buried directly in embankments and fills.
What are the different water sources that are found and sampled from
Surface water, Groundwater, Spring water, Wastewater, Ice, Spring water
Water bodies are classified as followed:
Class I: Potable water supply.
Class II: Shellfish propagation and harvesting. Class III: Recreational propagation and maintenance of fish and wildlife.
Class IV: Agricultural water supply.
Class V: Navigation, utility and industrial use.
When Sampling surface water
Ensure that non-homogeneous particles have been removed, such as plant material
The number and type of samples to collect depends on a variety of factors, including
Width. Depth. Discharge point. Amount of suspended sediment. Aquatic life present
A __________________ is the best choice to determine the maximum concentration of a contaminant
discrete grab sample
A Secchi Disk is a circular disk to measure
the transparency of a body of water
factors must be taken into account when sampling is done in rivers and streams, such as…
o Accessibility. o Point of contamination. o Flow rate. o Changes in stream or river channel. o Type of bed, depth and turbulence. o Structure present. o Safety.
factors must be taken into account when sampling is done in lakes, such as…
o Accessibility.
o Spatial stability.
o Thermal stability.
factors must be taken into account when sampling is done in Groundwater, such as…
o Site of contamination.
o Purification and treatment processes.
Common particle sizes observed are:
Gravel (2-60mm)
Sand (0.6-2mm)
Silt (0.006-0.06mm)
Clay (<0.002mm)
Other parameters that can be determined from a sieve analysis of a sample of soil are:
effective porosity, soil type and the ability to define the apparent soil order and horizons
Parameters must be set out within a soil sampling program regarding:
Pollutants, Depth to collect samples from, Sampling equipment, Sample containers, Number of samples, Identify analytical parameters, Identify preservation and sample storage
The nature of the analyte dictates the ______,__________.________. and_________ within the sampling device
depth, sampling device, construction and choice of materials
Pollutants migrate slowly through soil; this migration is dependent on
density, solubility and viscosity of the pollutant
Describe the four types of air quality decisions
Determination of effects,
Identification of pollutants causing effects,
Source attribution, and
Emissions control
Air samples collected from the environment fall into one of the following four categories:
- Ambient Air sample.
- Indoor Air sample.
- Emissions sample – automobiles, incinerator stacks, etc.
- Soil atmosphere – landfills, contaminated soils from spills, etc
The following must be considered when selecting the sampling site:
Source of contamination. Air flow and direction and velocity. Density of contaminants. Intensity of sunlight. Time of day. Presence of obstructions such as trees and buildings. Traffic. Site access and amenities.
Meteorological effects to consider when sampling:
Wind direction and speed.
temperature.
Atmospheric stability and pressure.
Precipitation.
The four collection methods are:
- Absorption/Adsorption
- Filtration
- Whole Air Sampling
- Cryogenics
Total Volume of Air Collected =
Flow Rate x Total Sampling Time
Why are Field Analysis necessary?
because the nature of any sample will change as soon as it is removed from its original environment, making the measurements non-representative