The Sierra Fund Carrie Monohan, Ph.D. Science Director

Transcription

1 The Sierra Fund Carrie Monohan, Ph.D. Science Director

2 Mercury and the Gold Rush SOURCE: USGS Fact Sheet

3 Mercury and the Gold Rush Mercury was used during hard rock and hydraulic mining. It is still entrained in the river gravels. Deer Creek 1908 Greenhorn Creek 2011

4 Mercury in Fish

5 Selenium: A Silver Bullet? There is an Se-Hg effect Does it negate the effects of MeHg in humans? Human study on Se-MeHg effects? Many human studies on MeHg effects: Harvard mercury researcher Philippe Grandjean Cognitive performance of children prenatally exposed to safe levels of methylmercury Methylmercury neurotoxicity in Amazonian children downstream from gold mining Jane Hightower, M.D. Mercury levels in high-end consumers of fish

6 Cal/EPA Office of Environmental Health Hazard Assessment (OEHHA). December 2003 (updated 2009). Health Advisory for Selected Water Bodies in the Northern Sierra Nevada Foothills (Nevada, Placer, and Yuba Counties).

7 Fish Sampling in Feather River Watershed 1) California State Department of Public Health, 1971 Mercury in the California Environment 2) UC Davis, 1997 Gold mining impacts on food chain mercury in northwestern Sierra Nevada streams 3) USGS, 2000 Water-Quality Assessment of the Sacramento River Basin, California: Organic Contaminant and Trace Element Surveys of Streambed Sediment and Tissue of Aquatic Organisms 4) Toxic Substances Monitoring Program, 2002 State Water Resources Control Board SWRCB-DWQ 5) PG&E, 2006 Upper North Fork Feather River Project FERC No Application of new license

8 Areas Sampled include: Lake Almanor Butt Lake Indian Creek Nelson Creek Spanish Creek Yellow Creek Jack Slough Butt Valley Reservoir Lower Feather River Feather River near Nicolaus Highway 99 bridge Oroville reservoir East Branch Downstream from Nelson Ck Upstream from Clio Caribou Branch SOURCE: Eis.sfei.org/cwqmc/step/

9 Feather River Watershed Trout Trout Steelhead Trout Brown Trout Rainbow Trout Lake Trout Chinook Salmon Coho Salmon Kokanee Hg Hg Hg Hg Hg Hg Hg Hg (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) Hatchery Reservoir/ Lake River/ Creek Feather River Total DATA SOURCES: See slide #7

10 Fish Mercury Data and 303(d) Waterbody 303(d) Listed Species # Hg (ppm) Lake Almanor Yes Smallmouth Bass Antelope Lake Brown BullHead Largemouth Bass Butt Valley Reservoir Smallmounth Bass Oroville Yes Carp 0.26 Smallmouth Bass 0.44 Feather River North Fork above Beldon Bridge Yes Trout 0.04 Middle Fork at Sloat Brown Trout 0.09 Rainbow Trout 0.08 Upstream of Yuba City Largemouth Bass 0.41 Sac Sucker 0.46 Upstream of Clio Brook Trout 0.05 Largemouth Bass 0.06 Rainbow Trout 0.04 Lower Feather Catfish Largemouth Bass Big Chico Creek Yes Butte Creek Yes DATA SOURCES: See slide #7

11 303(d)-listed SOURCE:

12 Fish Advisory for Lower Feather River SOURCE: California Office of Environmental Health Hazard Assessment,

13 Gold County Angler Survey A Pilot Study to Assess Mercury Exposure from Sport Fish Consumption in the Sierra Nevada Available at:

14 Are people eating the fish? Survey Locations Deer Creek Upper Scotts Flat Lake Lower Scotts Flat Lake Lake Wildwood Bear River Rollins Lake Lake Combie Camp Far West Reservoir South Yuba River North Yuba River Lake Englebright Lower Yuba River (below Englebright) Folsom Lake Natoma Available at:

15 Location of Surveys Surveys Completed 69 were collected in were collected in were completed in were completed in 2012 Available at:

16 Are you going to eat the fish you catch today? Don't Know 1% Are you going to feed the fish you catch to your family? Don't Know 1% No 44% Yes 55% 46% Household Consumption Information 52% No 39% Yes 60% 7% Children in household eaten sport fish in the last year Women b/w eaten sport fish in the last year Pregnant or nursing women eaten sport fish in the last year Available at:

17 Rainbow Trout Bass, any species Cat Fish Brown Trout Kokanne Salmon Crappie Sun Fish/Blue Gill Cray Fish Other Chinnok Salmon Sturgen Clams 77% Fish Consumption By Species 59% Do you EVER eat the fish that you or someone you know catches? No 19% 39% 35% 33% Yes 80% 25% 23% 23% 19% 12% 9% 8% Available at:

18 µg Methylmercury/Day Gold County Angler Survey 200 Methylmercury Exposure from Sport Fish Consumption Women over 45 and Men 150 Sensitive Populations* OEHHA Safe Level for Sensitive Populations*-assume 70 kg (154lbs) µg MeHg/Day 0 7µg MeHg/Day n= 215 In 130 surveys mercury exposure from fish = 0 μg MeHg/Day Survey Participant Available at:

19 Angler Survey Summary and Conclusions 80% of anglers reported eating sport fish 50% feed the fish they catch to women/children 10% are consuming mercury at levels above the OEHHA safe eating guidelines Posted warnings were not present at most fishing locations Exposure potential is high with limited awareness Available at:

20 This information applies to all lakes and reservoirs in CA without sitespecific advice (OEHHA, 2013) SOURCE: California Office of Environmental Health Hazard Assessment,

21 Dust and the Gold Rush Rock crushed in mills Tons of waste rock spread over large areas Piles of rocks used for many things Construction Road surfaces Fill Dirt

22 SOURCE: California Department of Toxic Substances Control

23 SOURCE: California Department of Toxic Substances Control

24 Dust and Mounds Recreation creates dust Trails go through abandoned mines Is there a problem? Exposure scenarios Site specific risk assessments How big is this problem?

25 A Pilot Study to Assess Exposure Potential to Toxics from Mine Waste and Naturally Occurring Asbestos Available at: /TrailsAssessmentREPORT.pdf

26 Available at:

27 How high is too high? Lab Detection Limits US EPA PRGs for Residential Cal EPA Industrial BLM Risk Management Criteria for Initial Screening Secondary Screening Element Symbol (ME-ICP41m) Soil CHHSLs Recreation Level Level (mg/kg) (mg/kg) (mg/kg) (mg/kg) (mg/kg) (mg/kg) Arsenic As Chromium Cr , ,000 Lead Pb Initial Screening Level-not good Secondary Screening Level- really NOT good SOURCES: Bureau of Land Management (BLM) Risk management Criteria for Metals at BLM Mining Sites. Technical note 390 rev. October California Environmental Protection Agency (Cal/EPA). (2009). Use of California Human Health Screening Levels (CHHSLs) in Evaluation of Contaminated Properties. California Environment Protection Agency. January 2005.

28 Lead.Asbestos. Available at:

29 Recommendation Recreational Trails Survey Quantify dust exposure for recreational activities in the higher risk areas identified. Dust monitoring activities by qualified professionals with adequate health and safety training and protective equipment. Activity based air sampling (ABS) Available at:

30 What can we do? Public Meetings Health professionals involved Maternal Health Awareness Fish Consumption Advisories Dust Exposure Signs Asbestos-NOA Trails AML Trails PA/SI NOA

31 Long Term Solution-Clean it Up Mercury Removal from contaminated areas What was once a non-point source is no longer Abandoned Mine Remediation What was once remote is no longer Thank you!

32 Resources Mentioned Grandjean, Philippe. Cognitive performance of children prenatally exposed to safe levels of methylmercury. Environmental Res 77(section A): Grandjean, Philippe. Methylmercury neurotoxicity in Amazonian children downstream from gold mining. Environment Health Perspect 107(7): Hightower, Jane. Mercury Levels in High-End Fish Consumers of Fish. Environmental Medicine. Vol No.4 April Pages Interagency Committee on Environmental Mercury Mercury in the California Environment. California State Department of Public Health\. PG&E 2006 Upper North Fork Feather River Project FERC No Application of new license. Toxic Substances Monitoring Program 2002, State Water Resources Control Board SWRCB-DWQ. UC Davis 1997 Slotton, D.G., S.M. Ayers, J.E. Reuter, and C.R. Goldman Gold mining impacts on food chain mercury in northwestern Sierra Nevada streams (1997 revision). In Sacramento River Mercury Control Planning Project. USGS 2000 Domagalski, J.L., P.D. Dileanis, D.L. Knifong, C.M. Munday, J.T. May, B.J. Dawson, J.L. Shelton, and C.N. Alpers Water-Quality Assessment of the Sacramento River Basin, California: Water-Quality, Sediment and Tissue Chemistry, and Biological Data, : Organic Contaminant and Trace Element Surveys of Streambed Sediment and Tissue of Aquatic Organisms. U.S. Geological Survey Open-File Report Available at: Accessed: March 2002.