A reference site is One of a population of bench mark or control sampling locations that, taken collectively, represent an ecoregion or other large biogeographic area; the sites, as a whole, represent the best ecological conditions that can be reasonably attained, given the prevailing topography, soil, geology, potential vegetation, and general land use of the region or clearly subnominal condition.
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A Reference Site is specific locality on a waterbody which is unimpaired or minimally impaired and is representative of the expected Biological Integrity of other localities on the same waterbody or nearby waterbodies.
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A reference site is a site on a waterbody which represents the best attainable physical habitat, water chemistry, and biological parameters for specific environmental conditions.
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A Reference Site is a minimally impaired site that is representative of the expected ecological conditions and integrity of other sites of the same type and region.