EXISTING QUALITY definition
EXISTING QUALITY means the numeric value that represents the quality of a water body and is generally used for comparison with the water quality standard. Existing quality shall be calculated as:
EXISTING QUALITY means the 85th percentile of the data for total ammonia, nitrate, and the dissolved metals, the 50th percentile for total recoverable metals, the 15th percentile of such data for dissolved oxygen, the geometric mean of such data for E. coli, and the range between the 15th and 85th percentiles for pH. For temperature, for the purposes of implementing the chronic standard, “existing quality” means the maximum WAT in a three year period.
EXISTING QUALITY means the 85th percentile of the data for total ammonia, nitrate, and the dissolved metals, the 50th percentile for total recoverable metals, the 15th percentile for dissolved oxygen, the geometric mean for E. coli, and the range between the 15th and 85th percentiles for pH. For temperature, for the purposes of implementing the acute and chronic standard, “existing quality” is the seasonal maximum DM and WAT and which allows one warming event with a 3-year average exceedance frequency. For data records less than or equal to 3 years, existing quality is equal to the maximum WAT and DM. For data records with 4-6 years, one warming event above the standard is permitted.