surface water sampling methodology

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Surface water sampling methodology Sampling should only be undertaken by appropriately trained and experienced personnel. Preparation for a sampling event must include knowledge of and compliance with site Occupational Health and Safety protocols for the sampling activities, including familiarisation with relevant Material Safety Data sheets and precautions necessary for handling chemicals. Integrity of samples To ensure the reliability and interpretability of the collected data, appropriate documentation should be incorporated into the monitoring program that records sample movement from collection to data reporting and ensures that analytical data is ascribed to the correct location. Appropriate chain of custody information for…show more content…
The total dissolved solids in the sample water can be calculated from this reading using the following formula: TDS = (0.548 x EC) + (2.2 x 10-6 x EC2) As with pH measurement, calibration of conductivity meters should be performed using standards of a known concentration appropriate to the anticipated range of conductivity of the water to be sampled. Calibration standards should be stored appropriately (e.g. do not exceed ‘use by’ dates, refrigeration) to ensure their accuracy. Dissolved Oxygen: The amount of dissolved oxygen in a sample can vary with depth, temperature, and biological demand. Measurements of dissolved oxygen can be most accurately obtained by placing the probe directly into the water body to be sampled in an area with flow or moved, not too vigorously, to simulate flow. Reduction/Oxidation potential (Redox): Measures the reducing or oxidising potential of a water body. Field meters will return a value in Volts or millivolts with a negative value indicating a reducing environment and a positive value indicating an oxidising one. Alkalinity/Acidity: Tests the relative acidity or alkalinity of a water body. Alkalinity/Acidity can result from natural sources such as the dissolution of carbonates or the presence of mineral or humic acids. Field testing of Alkalinity or acidity can be performed using commercially available test strips or indicator solutions to provide approximate values.
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