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Ecological Risk Assessment Step 5
Step 5 of the Ecological Risk Assessment (ERA) 8-step process is the Baseline ERA (BERA) Field Sampling Plan Verification. The primary purpose of field verification of the sampling plan is to ensure that the samples specified by the Work Plan and Sampling Analysis Plan (SAP) (Step 4) actually can be collected. This is necessary because conditions may have changed between the time the sampling plan was developed and when the samples are supposed to be collected. Changes may include factors such as flooding, drought, too much or too little snow and ice, and some of the species that were expected to be there are no longer present (or are in too small numbers to allow for collection).
During this step, previously obtained information should be checked, and the practicality of sampling will need to be checked by a site visit. Initial sampling will determine if the targeted species are present and collectable in sufficient numbers or biomass to meet data quality objectives. This preliminary field assessment also allows for final confirmation of the habitats that exist on or near the site.
Final decisions on reference areas should also be made in this step. Characteristics to be evaluated for deciding on reference areas should include slope of the land, habitat, species potentially present, soil and sediment characteristics, and for surface waters: flow rates, water depth, temperature, turbidity (how cloudy the water is), oxygen levels, water hardness, and pH. Several reference sites might be necessary depending on the variables associated with the reference and contaminated sites.