Florida Administrative Code (Last Updated: June 27, 2024) |
62. Department of Environmental Protection |
D62. Departmental |
62-303. Identification Of Impaired Surface Waters |
1(1) The Department shall reexamine the data used in Rule 1162-303.320, 12F.A.C., to determine whether water quality criteria are met.
21(a) If values exceeding the criteria are not due to pollutant discharges or reflect natural background conditions, including seasonal or other natural variations, the water shall not be listed on the Verified List. In such cases, the Department shall note for the record why the water was not listed and provide the basis for its determination that the exceedances were not due to pollutant discharges.
86(b) If the Department has information suggesting that the values not meeting the dissolved oxygen (DO) criterion are due to natural background conditions, it is the Department’s intent to support that conclusion through the use of Biological Health Assessment procedures referenced in Rule 12962-303.330, 130F.A.C. The waterbody or segment shall not be included on the Verified List for DO if two or more temporally independent Biological Health Assessments indicate the waterbody supports the protection and maintenance of a healthy, well-balanced population of fish and wildlife. 171The Biological Health Assessments shall be conducted either in the same waterbody segment, or for streams, in the contiguous waterbody segment downstream of the segment where the water quality samples were taken. These Biological Health Assessments shall be conducted on the same day or after the water quality samples were collected.
222(2) If the water was listed on the Planning List and there were insufficient data from the most recent five years of the Planning List assessment to meet the data distribution requirements of subsection 25662-303.320(4), 257F.A.C., and to meet a minimum sample size for verification of twenty samples, additional data will be collected as needed to provide a minimum sample size of twenty. Once these additional data are collected, the Department shall re-evaluate the data using the approach outlined in subsection 30362-303.320(1), 304F.A.C., but using Table 3, and place waters on the Verified List when 10% or more of the samples do not meet the applicable criteria, with a minimum of a 90% confidence level using a binomial distribution. The Department shall limit the analysis to data collected during the last 7.5 years. For sample sizes greater than 500, the Department shall calculate the number of samples not meeting the criterion that are needed for the given sample size using the binomial distribution.
385Table 3: Verified List
389Minimum number of samples not meeting an applicable water quality criterion needed to put a water on the
407Verified List with at least 90% confidence.
414Sample sizes
416Are listed if they have at least this # of samples that do not meet a criterion
433Sample sizes
435Are listed if they have at least this # of samples that do not meet a criterion
452From
453To
454From
455To
45620
45725
4585
459254
460262
46133
46226
46332
4646
465263
466270
46734
46833
46940
4707
471271
472279
47335
47441
47547
4768
477280
478288
47936
48048
48155
4829
483289
484297
48537
48656
48763
48810
489298
490306
49138
49264
49371
49411
495307
496315
49739
49872
49979
50012
501316
502324
50340
50480
50588
50613
507325
508333
50941
51089
51196
51214
513334
514343
51542
51697
517104
51815
519344
520352
52143
522105
523113
52416
525353
526361
52744
528114
529121
53017
531362
532370
53345
534122
535130
53618
537371
538379
53946
540131
541138
54219
543380
544388
54547
546139
547147
54820
549389
550397
55148
552148
553156
55421
555398
556406
55749
558157
559164
56022
561407
562415
56350
564165
565173
56623
567416
568424
56951
570174
571182
57224
573425
574434
57552
576183
577191
57825
579435
580443
58153
582192
583199
58426
585444
586452
58754
588200
589208
59027
591453
592461
59355
594209
595217
59628
597462
598470
59956
600218
601226
60229
603471
604479
60557
606227
607235
60830
609480
610489
61158
612236
613244
61431
615490
616498
61759
618245
619253
62032
621499
622500
62360
624(3) If the waterbody was placed on the Planning List based on worst case values used to represent multiple samples taken during a four day period, the Department shall evaluate whether the worst case value should be excluded from the analysis pursuant to subsections (4) and (5). If the worst case value should not be used, the Department shall then re-evaluate the data following the methodology in subsection 69262-303.420(2), 693F.A.C., using the more representative worst case value or, if all valid values are below acutely toxic levels, the median value.
714(4) If the waterbody was listed on the Planning List based on samples that do not meet water quality criteria for metals, the metals data shall be excluded if it is determined that the quality assurance requirements of subsection 75362-303.320(10), 754F.A.C., were not met or that the sample was not collected and analyzed using clean techniques, if the use of clean techniques is appropriate. The Department shall re-evaluate the remaining valid data using the methodology in subsection 79162-303.420(2), 792F.A.C., excluding any data that cannot be validated.
800(5) Values that exceed possible physical or chemical measurement constraints (pH greater than 14, for example) or that represent data transcription errors, outliers the Department determines are not valid measures of water quality, water quality criteria exceedances due solely to violations of specific effluent limitations contained in state permits authorizing discharges to surface waters, water quality criteria exceedances within permitted mixing zones for those parameters for which the mixing zones are in effect, and water quality data collected during extended drought or following contaminant spills, discharges due to upsets or bypasses from permitted facilities, or rainfall in excess of the 25-year, 24-hour storm, shall be excluded from the assessment carried out under this rule. However, the Department shall note for the record that the data were excluded and explain why they were excluded.
933(6) Once the additional data review is completed pursuant to subsections (1) through (5), the Department shall re-evaluate the data and shall include waters on the Verified List that meet the criteria in subsection 96762-303.420(2) 968or paragraph 97062-303.320(7)(b), 971F.A.C.
972(7) Notwithstanding the requirements of subsection (2), water segments shall also be included on the Verified List if, based on representative data collected and analyzed in accordance with Chapter 62-160, F.A.C.:
1003(a) For parameters other than bacteriological water quality criteria, there are less than twenty samples, but there are five or more samples that do not meet an applicable water quality criterion based on data from at least five temporally independent sampling events, or
1046(b) Scientifically credible and compelling information regarding the magnitude, frequency, or duration of samples that do not meet an applicable water quality criterion 1069provides overwhelming evidence of impairment. Any determinations to list waters based on this provision shall be documented, and the documentation shall include the basis for the decision.
1096(c) For any water chemistry data used to list waters under paragraph 110862-303.420(7)(b), 1109F.A.C., the Department shall include in the administrative record all of the applicable data quality assessment elements listed in Table 2 of the Department’s Guidance Document “Data Quality Assessment Elements for Identification of Impaired Surface Waters” (DEP EAS 01-01, April 2001), which was incorporated by reference in subsection 115762-303.320(9), 1158F.A.C.
1159(8) 1160For lakes, the daily average DO level shall be calculated as the average of measurements collected in the upper two meters of the water column at the same location on the same day. For all other fresh waters, the daily average freshwater DO level shall be calculated as the average of all measurements collected in the water column at the same location and on the same day. If 1228any individual DO measurement is greater than 100 percent saturation, 100 percent shall be substituted for that value for the purpose of calculating daily averages.
1253(9) The daily average freshwater DO criteria shall be assessed preferentially using daily average values calculated from full days of diel monitoring data. A full day of diel data shall consist of 24 hours of measurements collected at a regular time interval of no longer than one hour. If diel monitoring data are not available, instantaneous samples may be used to assess the DO criterion by comparing the instantaneous value with a time-of-day-specific translation of the daily average criterion. To determine the time-of-day-specific translation of the daily average criterion, the time (T) at which the DO sample was taken (in minutes past midnight) is entered into the appropriate equation below for the applicable region and waterbody type. The actual DO measurement collected at a given time is assessed against the calculated time-of-day-specific translation for that time, and if the instantaneous DO is greater than or equal to the calculated value, the daily average DO criterion is achieved.
1410Region1411Equations for Time-of-Day-Specific Translation of the Daily Average DO Criterion
1421Streams
1422Northeast + Big Bend14261.1844 x 101429-13 1430• T14325 1433– 4.1432 x 101437-10 1438• T14404 1441+ 4.7729 x 101445-7 1446• T14483 1449– 1.9692 x 101453-41454• T14562 1457+ 0.02314 • T + 31.24
1463Peninsula + Everglades14661.9888 x 101469-13 1470• T14725 1473– 6.8941 x 101477-10 1478• T14804 1481+ 7.8373 x 101485-7 1486• T14883 1489– 3.1598 x 101493-41494• T14962 1497+ 0.03551 • T + 33.43
1503Panhandle West15059.0851 x 101508-14 1509• T15115 1512– 2.9941 x 101516-10 1517• T15194 1520+ 3.1560 x 101524-7 1525• T15273 1528– 1.0851 x 101532-41533• T15352 1536+ 0.006285 • T + 65.61
1542Lakes
1543Northeast + Big Bend15471.4578 x 101550-13 1551• T15535 1554– 5.5607 x 101558-10 1559• T15614 1562+ 7.0683 x 101566-7 1567• T15693 1570– 3.1879 x 101574-41575• T15772 1578+ 0.02817 • T + 34.19
1584Peninsula + Everglades15871.3709 x 101590-13 1591• T15935 1594– 5.0496 x 101598-10 1599• T16014 1602+ 6.1352 x 101606-7 1607• T16093 1610- 2.5817 x 101614-41615• T16172 1618+ 0.01960 • T + 37.14
1624Panhandle West16267.1190 x 101629-14 1630• T16325 1633– 2.6420 x 101637-10 1638• T16404 1641+ 3.2247 x 101645-7 1646• T16483 1649– 1.3607 x 101653-41654• T16562 1657+ 0.01071 • T + 66.35
1663If multiple instantaneous DO samples are available in a day, the time-of-day-specific translation of the daily average criterion will be calculated for each individual sample. Achievement of the daily average DO criterion will be assessed by comparing the average of the actual DO measurements collected at each time against the average of the calculated time-of-day-specific translations for each time. If the average of the measured DO values is greater than or equal to the average of the time-of-day- specific translations of the criteria, the daily average DO criterion is achieved. An average of multiple daily values calculated in this manner will be considered as a single sample for assessment purposes.
1773(10) For predominantly marine waters, the Department shall evaluate the daily average DO criterion using Table 3 set forth in subsection 179462-303.420(1), 1795F.A.C., above, and shall also evaluate whether the seven-day and 30-day average criteria have been achieved during the verified period. A water segment shall be placed on the Verified List for DO impairment if the number of samples below the daily average DO criterion is greater than or equal to the number listed in Table 3 for the given sample size, or if there is more than one weekly average value below the weekly average DO criterion in any twelve week period of the verified period or more than one monthly average value below the monthly average DO criterion in any calendar year of the verified period. Prior to placing a waterbody on the Verified List, the Department shall identify the causative pollutant(s) responsible for the exceedances of the DO criteria. Before assessing the weekly and monthly average DO criterion, the DO data shall be evaluated pursuant to subsections 194462-303.420(3) 1945and (5), F.A.C.
1948(a) 1949If any individual DO measurement is greater than 100 percent saturation, 100 1961percent shall be substituted 1965for that value for the purpose of calculating daily, weekly and monthly averag1978es.
1979(b) Where DO values are collected at multiple depths at a given station and time, the average of the values shall be used to represent the measurements unless any of the individual DO values are less than 2 mg/l, in which case the lower 25th percentile of the measured values shall be used.
2032(c) 2033For assessment purposes, the seven-day average DO percent saturation shall be calculated as a weekly average using a minimum of three full days of diel data collected 2060within a week, 2063or a minimum of ten grab samples collected over at least three days within a week, with each sample measured at least four hours apart.
2088(d) For assessment purposes, the 30-day average DO percent saturation shall be calculated as a monthly average using a minimum of three full days of diel data, with each diel sampling conducted in different weeks of the month, or grab samples collected from a minimum of ten different days of the month.
2140(e) A full day of diel data shall consist of 24 hours of measurements collected at a regular time interval of no longer than one hour.
2166(11) For assessment of the DO criteria for the portions of the Suwannee, Withlacoochee (North), and Santa Fe Rivers utilized by the Gulf Sturgeon, and in the portions of the Santa Fe and New Rivers utilized by the Oval Pigtoe Mussel, waters will be placed on the Verified List when more than 50 percent of the measurements are below the applicable median or more than 10 percent of the daily average values are below the applicable 10th percentile values, specified in Appendix I of the “2252Technical Support Document: Derivation of Dissolved Oxygen Criteria to Protect Aquatic Life in Florida’s Fresh and Marine Waters,2270” (2272http://www.flrules.org/Gateway/reference.asp?No=Ref-029722274) which was incorporated by reference in subsection 228262-303.320(5), 2283F.A.C, at a minimum of a 90 percent confidence level using the binomial distribution.
2297(12) For the assessment of the DO criteria, any DO data collected as a concentration in mg/L shall be converted to percent saturation using the temperature and salinity measured at the same location within fifteen minutes of the DO measurement. Percent DO saturation shall be calculated using the method in Section 5.4 of the “2352Technical Support Document: Derivation of Dissolved Oxygen Criteria to Protect Aquatic Life in Florida’s Fresh and Marine Waters,2370” (2372http://www.flrules.org/Gateway/reference.asp?No=Ref-029712374) which was incorporated by reference in subsection 238262-303.320(11), 2383F.A.C.
2384(13) A water segment shall be placed on the Verified List for DO impairment if there has been a statistically significant decreasing trend in DO levels or an increasing trend in the range of daily DO fluctuations over the verified period at the 95 percent confidence level using a one-sided Seasonal Kendall test for trend, as described in Helsel, D.R. and R.M. Hirsch, 2002, Statistical Methods in Water Resources, USGS, pages 338 through 340 (2459http://www.flrules.org/Gateway/reference.asp?No=Ref-029732461), which were incorporated by reference in subsection 246962-303.320(14) 2470F.A.C., 2471after controlling for or removing the effects of confounding variables, such as climatic and hydrologic cycles, quality assurance issues, and changes in analytical methods. 2495Water segments shall not be placed on the Verified List for DO impairment until the Department has identified a pollutant causing the decrease or if the decrease in DO levels was authorized 2527under Rules 252962-302.300 2530and 253162-4.242, 2532F.A.C.
2533(14) 2534For assessment 2536of the 30-day average total ammonia criterion, 2543the monthly average total ammonia shall be calculated for a station using a minimum of four samples collected within the month. A water segment shall be placed on the Verified List for total ammonia impairment if a station within the segment has more than one monthly average value above the 30-day average criterion in any calendar year of the verified period.
2604Rulemaking Authority 2606403.061, 2607403.067 FS. 2609Law Implemented 2611403.021(11), 2612403.062, 2613403.067 FS. 2615History–New 6-10-02, Amended 12-11-06, 7-2-12, 8-1-13, 2-17-16.