If selected as the preferred method, TCEQ intends to use a stand-alone chlorophyll a criteria that is adjusted to be equivalent to chlorophyll a criteria with supplemental screening levels. If stand-alone chlorophyll a criteria were to be adopted, then references to supplemental screening levels for total phosphorus and transparency would be omitted in draft language in §307.2, §307.7, §307.9, and §307.10, and only the statistically adjusted stand-alone chlorophyll a criteria would appear in the final methodology.
Criteria for chlorophyll a are planned to be assessed with long-term medians of sampling data. Criteria for chlorophyll a are attained when they are not exceeded by the median of monitoring data results.
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