Update on Sediment Assessment

Transcription

1 Florida s Mercury TMDL Project Update on Sediment Assessment Lori Balinsky, Paul Blair, Keith Davie, Mike Eckles, Peter Folland, Chris Green, Shannon Gerardi, Pam Novak and Tom Seal Florida DEP Watershed Monitoring Section

2 Florida s Mercury TMDL Project 1 Staff in FDEP s Bureau of Assessment and Restoration Support (BARS) are developing a total maximum daily load (TMDL) for mercury in Florida freshwater systems. In 2007 BARS staff asked the Watershed Monitoring Section (WMS) for assistance in sample plan design, and later, for help in the collection of samples, specifically sediments.

3 Florida s Mercury TMDL Project 2 This project involves not just FDEP staff but also staff and scientists from the Florida Fish & Wildlife Commission (FWCC), the University of Michigan (UM), and Curt Pollman, a national expert in mercury issues based in Gainesville, FL.

4 How Mercury Enters the Environment Dry Deposition Wet Deposition Air Emissions (wet + dry) Geologic Sources (soil, rock, base flow) Detritus Hg Hg Hg Hg Methylation Water Body Bacterial action (water and sediment) Zooplankton Small fish Predatory Fish Micropterus salmoides Compliments of Lori Tilley City of Jacksonville

5 Mercury Cycle in Freshwater Ecosystems

6 Florida s Mercury TMDL Project 3 The Department s t Mercury TMDL research group needed a statewide geographical database of surface waters (lakes, rivers, streams) from which to randomly select sites. The WMS Status t Network provided d just such a framework for this sampling approach.

7 Florida s Mercury TMDL Project 4 A list of Status Network lakes and streams was provided to Curt Pollman, giving him a much more robust set of surface water resources from which to choose. 1) Status Network Lakes dataset (n = 1,931) 2) Status t Network Streams dataset t (n = 1,820) 3) FWCC (2006) lakes data set (n = 100) 4) FWCC largemouth bass Hg data set for Florida lakes and streams (n = 210) 5) USEPA Everglades Ecosystem Program data

8 Florida s Mercury TMDL Project 5 After site selection was finalized, FWCC staff began sample collection in late 2008 by electroshocking a few unlucky largemouth bass, or a few more spotted sunfish if no bass were present. After the fish are filleted, FWCC collects a water sample as well as field analytes. Fish and water samples are shipped to the DEP Central Laboratory.

9 Fish Collections FWCC targets t 12 legal l size largemouth bass per lake Micropterus salmoides floridanus Analytical Procedures Total length (mm) Weight (g) Sex Age (year using otoliths) Total Hg in homogenized axial muscle tissue

10 Alternative Fish Collection For sites with no bass, FWCC staff collect a surrogate species, the spotted sunfish (Lepomis punctatus), ubiquitous throughout Florida, particularly in low order streams in the Panhandle. The size range is 2 to 5 per fish.

11 Florida s Mercury TMDL Project 6 Next FWCC station GPS information is transferred to DEP and distributed to our samplers, who revisit the site (often months later) to collect a sediment sample plus additional field analytes. The sediment collection point is always at the same location as the water sample.

12 Florida s das Mercury ecuy TMDL Project 7 For the project, 128 lake stations will be sampled for fish, water and sediment. FWCC staff have sampled fish and water at 94 lake sites, and FDEP samplers have sampled lake sediments at 40 of them thus far.

13 Florida s Mercury TMDL Project 8 Ultimately all these aquatic data (fish Hg, water Hg, sediment Hg) will be combined with air and rainfall Hg data collected throughout Florida via contracts managed by other DEP staff. Together the overall dataset will be used by Curt Pollman to calculate a Hg TMDL for the Department.

14 Florida s Mercury TMDL Project 9 In a few weeks, WMS staff in Tampa (z4), Punta Gorda (z5), (5) and dp Port tstl St. Lucie (6) (z6) will begin mercury sediment sample collection. Updated site location information will be transferred soon to Zones 4, 5 and 6. Mercury sediment collection training i will coincide with the next scheduled audits by our WMS QA/QC officer.

15 Florida s Mercury TMDL Project 10 Sediment Sampling 3 sample jars are filled ml jar for Me Hg ml jar for trace metals and nutrients ml plastic bottle for Hg isotope work (sent to UM)

16 Florida s Mercury TMDL Project 11 Each DEP WMS Sampling team will need to be familiar with and follow the guidance of the Mercury TMDL Sediment Sampling Protocols document. In this project the blank is an equipment blank. Once the petite ponar is cleaned a final rinse is made. That rinse water is poured into a sample bottle and shipped as a water sample.

17 Contact Information for Sediment Questions Thomas Seal, ES III or Gail Sloane, EA Bureau of Watershed Management Watershed Monitoring Section 2600 Blair Stone Road, MS 3525 Tallahassee FL, (TLS) and (GMS) Website for Fresh and Marine Sediment Metals Interpretive Tools and Sediment Quality Guidelines: dep.state.fl.us/water/monitoring/sediments.htm