Environmental sampling
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This document discusses environmental sampling, focusing on water sampling. It covers three main areas of environmental sampling: water sampling, air sampling, and soil sampling. For water sampling, it is important to understand the water cycle, soil permeability and porosity, and basic water characteristics. The document then discusses the hydrologic cycle, soil permeability, water tables, groundwater vs. surface water, considerations before sampling like safety plans and permits, on-site observations and tests, sampling locations and flow calculations, and detention time.
Environmental sampling
- 1. A J A Y S H A R M A Ajay Sharma Environmental Sampling
- 2. Three major areas Ajay Sharma Water sampling Air sampling Soil sampling
- 3. Important criteria's for environmental sampling are Ajay Sharma Location Interferences with surrounding Instruments/ apparatus /tools Integrity & composure of individual
- 4. Water sampling Ajay Sharma To understand water sampling first understand water cycle (hydrologic cycle) in nature, soil characteristics (permeability & porosity) and basic characteristics of water such as temperature, dissolved oxygen and turbidity.
- 5. Hydrologic cycle Ajay Sharma Transfer of water between land, sea and atmosphere (air). Water precipitates onto land, may transpired by vegetation, runoff, sink into land and some part evaporate. Circulation of water in earths hydrosphere.
- 6. Permeability of soil Ajay Sharma Due to the existence of the inter-connected voids, soils are permeable. The permeable soils will allow water flow from points of high energy to points of low energy. Permeability is the parameter to characterize the ability of soil to transport water.
- 7. Water table Ajay Sharma Below a certain depth, all the interstices are filled with water. The upper surface of this water saturated zone is called the water table.
- 8. Ground & surface water Ajay Sharma Ground water: Water below the water table is ground water In area of higher water table, GW interacts with earths surface in form of seepage, streams and spring. Surface water: water in contact with atmosphere and earth surface is surface water.
- 9. Before sampling Ajay Sharma Make health and safety plan (be safe) Extra sample kits (how many duplicates) Sampling plan & strategy (what ,where & how) Turnaround time (communication with lab or project manager) Legal issues (access permit)
- 10. Site observations Ajay Sharma Color ,odour & turbidity (cloudiness) Algal bloom (consumes oxygen & give off toxins) Full description of weather activity on sampling time Any indication of interference or unusual activity
- 11. On site tests Ajay Sharma Those parameters that may change on way to laboratory should be tested immediately on site Chlorine can be measured with test kit Oxygen & temperature can be measured with meter
- 12. Sampling location Ajay Sharma One has to survey the site to determine the sampling locations. To conclude that there was a discharge from a particular facility, samples will have to be taken before discharge point, at discharge point, and below the discharge point. Flow estimates should be made (use basic mathematics skills) Sampler has to judge or predict how far downstream to sample so that a possible slug of pollutant might be found.
- 14. Flow rate calculations Ajay Sharma Amount of fluid flowing in given time is flow rate. Flow rate= Area(m2) Velocity (m/s) Daily Flow= (m3/s) 60 s/min. 1440 min/d
- 15. Detention time Ajay Sharma Length of time a drop of water or sediment remains in chamber. It is amount of time in which any tank fill up o overflow. Detection time= Volume of tank/ Flow rate