1. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Request to Discontinue Project HGOS Prepared for the Technical Oversight Committee 6/30/09 Mark Gabriel, Ph.D. South Florida Water Management District

2. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Project Background and History Project HGOS involves the quarterly collection of total mercury (THg) and methylmercury (MeHg) in surface water Collections have occurred at multiple stations (~20) throughout the Everglades Protection Area (EPA) since 2000 HGOS was established in 2000 as a modification to existing monitoring programs The intent of establishing HGOS was to incorporate improvements in sampling methodologies and analytical capabilities for surface water mercury monitoring

3. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Current HGOS Monitoring Stations *S12A *Station S12A is under project PIN (Project Inflow North)

4. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Justification for Discontinuing Project HGOS 1. 1.There has been no exceedance of the Florida Water Quality Standard of 12 ng/L for THg (Chapter 62-302, F.A.C.); There is no WQS for MeHg WQS

5. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Justification for Discontinuing Project HGOS (Cont.) 2.HGOS data is not applicable to area loading calculations 3.The research-related value of the HGOS data is limited An attempt was made to use HGOS THg/MeHg data to predict the spatial concentrations in fish throughout the EPA but there is only one HGOS station that overlaps a fish collection station (P33 [HGOS surface water], L67 [HGFS fish]) 4.The main focal point with regard to evaluating ecosystem mercury contamination is observing levels in fish tissue, feathers, etc.

6. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Current fish THg monitoring stations

7. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T 5.Percent MeHg* levels for all HGOS stations are similar to stations collected throughout the EPA indicating no cause for concern: From 2000 to present mean percentage of MeHg was 14.5% for HGOS project and 16% for all other projects 6.The HGOS project is not mandated or used by any other project 7.All District Everglades (ECP, CERP) projects have surface water THg and MeHg monitoring * (MeHg/THg)*100 Justification for Discontinuing Project HGOS (Cont.)

8. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Current surface water THg and MeHg monitoring stations S390, S392

9. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T 8.Overall, the HGOS program cost outweighs the benefits (~$30K/year [includes FTE time, sample analysis, and transportation]) Justification for Discontinuing Project HGOS (Cont.)

10. S O U T H F L O R I D A W A T E R M A N A G E M E N T D I S T R I C T Recommendation Stop sampling for project HGOS, effective immediately, and start the process for discontinuing the project