The Sierra Fund Carrie Monohan, Ph.D. Science Director Mercury and the Gold Rush
SOURCE: USGS Fact Sheet 2005-3014
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 Mercury in Fish 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 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). 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. 2105 Application of new license
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/ Feather River Watershed Trout
Steelhead Brown Rainbow Chinook Coho Trout Trout Trout Trout Lake Trout Salmon Salmon Kokanee
Hg Hg Hg Hg Hg Hg Hg Hg (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) # (ppm) Hatchery 0.09 6 0.12 5 Reservoir/ Lake 0.09 1 0.1 12 0.11 13 0.05 23 0.02 5 0.33 16 0.1 River/ Creek 0.08 2 0.07 55
Feather River Total 0.09 1 0.1 18 0.1 15 0.06 78 0.02 5 0.12 5 0.33 16 0.1 DATA SOURCES: See slide #7 Fish Mercury Data and 303(d)
Waterbody 303(d) Listed Species # Hg (ppm) Lake Almanor Yes Smallmouth Bass 34 0.15 Antelope Lake Brown BullHead 10 0.03 Largemouth Bass 17 0.11 Butt Valley Reservoir Smallmounth Bass 22 0.15 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 6 0.45 Largemouth Bass 10 0.38 Big Chico Creek Yes Butte Creek Yes DATA SOURCES: See slide #7 303(d)-listed
SOURCE: http://www.swrcb.ca.gov/centralvalley/water_issues/tmdl/impaired_waters_list/ Fish Advisory for Lower Feather River
SOURCE: California Office of Environmental Health Hazard Assessment, http://oehha.ca.gov/fish/so_cal/index.html Gold County Angler Survey
A Pilot Study to Assess Mercury Exposure from Sport Fish Consumption in the Sierra Nevada
Available at: http://www.sierrafund.org/pdf/AnglerSurvey.pdf 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: http://www.sierrafund.org/pdf/AnglerSurvey.pdf Location of Surveys 218 Surveys Completed
40 69 were collected in 2009 35 82 were collected in 2010 30 53 were completed in 2011 25 20 14 were completed in 2012 15 10 5 0
Available at: http://www.sierrafund.org/pdf/AnglerSurvey.pdf Are you going to feed Are you going to eat the fish you catch to the fish you catch your family? today? Don't Don't Know Know 1% 1%
No No 39% Yes 44% 60% Yes 55% Household Consumption Information
52% 46%
7%
Children in Women b/w 18-49 Pregnant or nursing household eaten eaten sport fish in women eaten sport sport fish in the last the last year fish in the last year year Available at: http://www.sierrafund.org/pdf/AnglerSurvey.pdf Do you EVER eat the fish that you or someone you know 77% catches?
Fish Consumption By Species No 19% 59%
39% 35% Yes 33% 80%
25% 23% 23% 19%
12%
9% 8%
Other
Clams
Sturgen
Crappie
Cat Fish Cat
Cray Fish Cray
Brown Trout Brown
Rainbow Trout Rainbow
Bass, any species any Bass,
Chinnok Salmon Chinnok
Kokanne Salmon Kokanne Sun Fish/Blue Gill Fish/Blue Sun Available at: http://www.sierrafund.org/pdf/AnglerSurvey.pdf Gold County Angler Survey Methylmercury Exposure from Sport Fish
200 Consumption
Women over 45 and Men
150 Sensitive Populations*
OEHHA Safe Level for Sensitive Populations*-assume 70 kg (154lbs)
100 µg Methylmercury/Day µg
50
21 µg MeHg/Day
7µg MeHg/Day 0 n= 215 Survey Participant In 130 surveys mercury exposure from fish = 0 μg MeHg/Day
Available at: http://www.sierrafund.org/pdf/AnglerSurvey.pdf 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: http://www.sierrafund.org/pdf/AnglerSurvey.pdf This information applies to all lakes and reservoirs in CA without site- specific advice (OEHHA, 2013)
SOURCE: California Office of Environmental Health Hazard Assessment, http://oehha.ca.gov/fish/so_cal/index.html 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 SOURCE: California Department of Toxic Substances Control SOURCE: California Department of Toxic Substances Control 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? A Pilot Study to Assess Exposure Potential to Toxics from Mine Waste and Naturally Occurring Asbestos
Available at: http://www.sierrafund.org/pdf /TrailsAssessmentREPORT.pdf Available at: http://www.sierrafund.org/pdf/TrailsAssessmentREPORT.pdf How high is too high?
US EPA BLM Risk Lab Detection PRGs for Cal EPA Management Initial Secondary Limits Residential Industrial Criteria for Screening Screening Element Symbol (ME-ICP41m) Soil CHHSLs Recreation Level Level (mg/kg) (mg/kg) (mg/kg) (mg/kg) (mg/kg) (mg/kg) Arsenic As 2 22 0.24 300 22 270 Chromium Cr 1 210 100,000 210 100,000 Lead Pb 2 400 320 1000 80 1000
Initial Screening Level-not good
Secondary Screening Level- really NOT good
SOURCES: Bureau of Land Management (BLM). 2004. Risk management Criteria for Metals at BLM Mining Sites. Technical note 390 rev. October 2004.
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. Lead….Asbestos….
Available at: http://www.sierrafund.org/pdf/TrailsAssessmentREPORT.pdf 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: http://www.sierrafund.org/pdf/TrailsAssessmentREPORT.pdf 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 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! Resources Mentioned
Grandjean, Philippe. Cognitive performance of children prenatally exposed to “safe” levels of methylmercury. Environmental Res 77(section A): 165-72.
Grandjean, Philippe. Methylmercury neurotoxicity in Amazonian children downstream from gold mining. Environment Health Perspect 107(7): 587-91.
Hightower, Jane. Mercury Levels in High-End Fish Consumers of Fish. Environmental Medicine. Vol. 111. No.4 April 2003. Pages 604-608.
Interagency Committee on Environmental Mercury 1971. Mercury in the California Environment. California State Department of Public Health\.
PG&E 2006 Upper North Fork Feather River Project FERC No. 2105 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. 1997. 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. 2000. Water-Quality Assessment of the Sacramento River Basin, California: Water-Quality, Sediment and Tissue Chemistry, and Biological Data, 1995-1998: Organic Contaminant and Trace Element Surveys of Streambed Sediment and Tissue of Aquatic Organisms. U.S. Geological Survey Open-File Report 00-391. Available at: http://water.wr.usgs.gov/sac_nawqa/waterindex.html. Accessed: March 2002.