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I I . MOSAIC STREAM RECLAMATION IN I HARDEE COUNTY t o HIGHLIGHTS: • Geomorphic assessment ■ Mine permitting • Stream classification • Hydraulic analysis ■ Natural channel design • Stream reclamation - I ECT assisted a phosphate rock mining company. a07,: iNkt :, ,..PiuE 4 , I Mosaic Fertilizer. L.L.C., with its efforts to obtain an environmental resource permit (ERP) from the Flori- 1 `.�� rZ•„�,' '?.b� ' r� Y f rgt da Department of Environmental Protection for the �w' aqt. ti t -.k J fi "ty fa proposed South Fort Meade mine site extension in 1'k7 r st '..' 3 '�”` %' • ,..•,f , es 'z-.y IHardee County, Florida. Florida's Administrative k oy'.. _ ; ��>1, -` �x ��f Code requires applicants to prepare and submit a 44 I< " ��a 3.a✓ '�.;<_r.j conceptual reclamation plan (CRP) for mining opera- '•4i »�j was .mss, tions in conformance with mine reclamation laws. .,7 - r -Ire k�.r ';.'" Among other reclamation requirements. the CRP re- ,;.[!;:?.1.4.-. , r4 �5 .l� { a 1'& quires a stream reclamation plan that demonstrates. . :.0•Ya< ti;¢'s1d 4--9' . /r $�E I with reasonable assurance, that the applicant can cre- Dar. %:(¢W - F- t„�t ,;,; ate reclamation streams post-mining that equal or ex- ceed the quality of existing streams pre-mining. Florida's mine reclamation laws also require ge- omorphic assessment of existing streams using Rosgen's stream classification system and geo- morphic assessment methodology. ECT prepared the stream reclamation plan and personnel served as expert witness in successfully obtaining the ERP. 1 The mine site contains more than 58.000 linear feet of natural stream channels and natural chan- nels that have been channelized or otherwise altered. ECT assessed the geomorphology of more I than 60 percent of the existing stream channels at 21 cross sections. Streams were classified to the Rosgen level-two classification. In addition to the collection of cross-sectional data. the val- ley and streambed slope, sinuosity. and meander geometry were documented at the 21 cross- ' section locations. Survey data were used to develop a site-specific regression of drainage area and bank cross-sectional area for sizing of reclaimed streams. The regression was compared to other regional curves and analyzed to determine the relative influence of watershed disturbances Iobserved throughout the site. The analysis showed that land clearing, cattle grazing. historical channelization. irrigation, and I artificial drainage of agricultural runoff had resulted in channel incision and widening. Existing stream segments with observable disturbances generally plotted above the best-fit line, while less disturbed stream segments plotted below the best-fit line. This condition within the data set was I accounted for by applying a uniform 30 percent reduction in cross-sectional area as a marein-of- safety. I . LV/ PROJECT PROFILE 41111=1111.1011W a Y` WDISCBLLVENWATERPROFOES\FLIMOSNC-SIRMRECL DOC-03091'