Fla. Admin. Code Ann. R. 62-303.350 - Assessments of Numeric Interpretation of Narrative Nutrient Criteria

(1) The numeric interpretations of the narrative nutrient criterion in Sections 62-302.531 and 62-302.532, F.A.C., and the nutrient impairment thresholds identified in Rules 62-303.351 through 62-303.354, F.A.C., shall be the primary means for assessing whether a water should be assessed further for nutrient impairment. Other information indicating an imbalance in flora or fauna due to nutrient enrichment, such as algal blooms or mats, excessive nuisance macrophyte growth, decrease in the distribution (either in density or areal coverage) of seagrasses or other submerged aquatic vegetation, adverse changes in algal species composition, and excessive diel oxygen swings, shall also be considered for placing waters on the Planning List.

(2) To be used to determine whether a waterbody should be assessed further for nutrient enrichment, data must meet the requirements of subsections and paragraphs (2), (3), (4)(a), (4)(e)-(g), (8), (9), (12) and (13), in Rule 62-303.320, F.A.C.

(3) To calculate an annual geometric or arithmetic mean for TN, TP, NO₃-NO₂, or chlorophyll a, there shall be at least four temporally-independent samples per year with at least one sample collected between May 1 and September 30 and at least one sample collected during the other months of the calendar year. To be treated as temporally-independent, samples must be collected at least one week apart.

(4) To assess nutrient criteria expressed as a long-term average of annual means for TN, TP, NO₃-NO₂, or chlorophyll a, the long-term average of annual means shall be based on data from at least 3 years meeting the minimum data requirements of subsection 62-303.350(3), F.A.C.

(5) To assess nutrient criteria expressed as a long-term average for TN, TP, NO₃-NO₂, or chlorophyll a, the long-term average for nutrients shall be based on a minimum of 10 data points over at least 3 years, with at least two temporally independent samples per year, with at least one sample collected between May 1 and September 30 and at least one sample collected during the other months of the calendar year.

(6) To be assessed under this chapter, except for data used to establish historical chlorophyll a levels, chlorophyll a data shall be determined using Department-approved methods as measured according to the DEP document titled, "Applicability of Chlorophyll a Methods" (DEP-SAS-002/10), dated October 24, 2011 (http://www.flrules.org/Gateway/reference.asp?No=Ref-02914), incorporated by reference herein, unless an alternative method is specifically approved by the Department under Chapter 62-160, F.A.C. Copies of the chlorophyll a document may be obtained by writing to the Florida Department of Environmental Protection, 2600 Blair Stone Road, MS #6511, Tallahassee, FL 32399-2400. Chlorophyll a data shall be corrected for or free from the interference of pheophytin.

Notes

Fla. Admin. Code Ann. R. 62-303.350

Rulemaking Authority 403.061, 403.067 FS. Law Implemented 403.062, 403.067 FS.

New 6-10-02, Amended 12-11-06, 7-2-12, Amended by Florida Register Volume 42, Number 021, February 02, 2016 effective 2/17/2016.

New 6-10-02, Amended 12-11-06, 7-2-12, 2-17-16.