The Sierra Fund Science Director Carrie Monohan, Ph.D. Mercury and - - PowerPoint PPT Presentation

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

Mercury and the Gold Rush

USGS Fact Sheet 2005-3014

Mercury and the Gold Rush

Deer Creek 1908 Greenhorn Creek 2011

Mercury was used during hardrock and hydraulic mining. It is still entrained in the river gravels.

Mercury in 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).

Limited Fish Consumption Advisories Mercury

OEHHA

Fish Advisory for Folsom Lake

http://oehha.ca.gov/fish/so_cal/folnat101108.html

Fish Advisory for Lake Natoma

http://oehha.ca.gov/fish/so_cal/LakeNatoma.html

Gold County Angler Survey

http://www.sierrafund.org/pdf/AnglerSurvey.pdf

A Pilot Study to Assess Mercury Exposure from Sport Fish Consumption in the Sierra Nevada

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

Are people eating the fish?

5 10 15 20 25 30 35 40

218 Surveys Completed 69 were collected in 2009 82 were collected in 2010 53 were completed in 2011 14 were completed in 2012

Location of Surveys

46% 52% 7%

Children in household eaten sport fish in the last year Women b/w 18-49 eaten sport fish in the last year Pregnant or nursing women eaten sport fish in the last year

Household Consumption Information

Are you going to eat the fish you catch today? Are you going to feed the fish you catch to your family?

Yes 60% No 39% Don't Know 1% Yes 55% No 44% Don't Know 1%

Do you EVER eat the fish that you or someone you know catches?

Yes 80% No 19%

77% 59% 39% 35% 33% 25% 23% 23% 19% 12% 9% 8%

Rainbow Trout Bass, any species Cat Fish Brown Trout Kokanne Salmon Crappie Sun Fish/Blue Gill Cray Fish Other Chinnok Salmon Sturgen Clams

Fish Consumption By Species

10 20 30 40 50 60 70 80 90

µg Methylmercury/Day Survey Participant

Methylmercury Exposure from Sport Fish Consumption

Women over 45 and Men Sensitive Populations* OEHHA Recommended Safe Level for Women over 45 and Men-assume 70kg (154lbs) OEHHA Safe Level for Sensitive Populations*-assume 70 kg person and 35kg child (154lbs and 77lbs child)

21 µg MeHg/Day 7µg MeHg/Day

Cal/EPA OEHHA. June 2008. Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDT’s, Dieldrin, Methylmercury, PCBs, Selenium, and Tosaphene.

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

www.sierrafund.org/mining/Gold_Country_Angler_Survey.pdf

This information applies to all lakes and reservoirs in CA without site- specific advice

(OEHHA, 2013)

Dust & 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

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

http://www.sierrafund.org/pdf/Trai lsAssessmentREPORT.pdf

How high is too high?

(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

Secondary Screening Level Symbol Element Lab Detection Limits (ME-ICP41m) US EPA PRGs for Residential Soil Cal EPA Industrial CHHSLs BLM Risk Management Criteria for Recreation Initial Screening Level

Secondary Screening Level- really NOT good Initial Screening Level-not good

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….

Downieville Area Results

 North Yuba Trail:

 Goodyears Bar (15% and 11% asbestos)  Slug Canyon (118-439 ppm arsenic)

 Columbo Mine above Sierra City (350-442 ppm arsenic)  Saddleback Road (1,570 ppm lead, 14% asbestos)  No elevated levels:

 Downieville First Divide Trail  Eureka Diggins OHV area

 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)

Recommendation Recreational Trails Survey

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

Carrie Monohan, Ph.D. carrie.monohan@sierrafund.org

Acknowledgements

These studies were funded in part by the Richard and Rhoda Goldman Fund, True North Foundation, The California Endowment, and The California Wellness Foundation. THANK YOU TO: All of our Working Group Advisors Volunteers that helped conduct the surveys including: Gold Country Fly Fishers, Deer Creek Citizen Monitors, and the Upper American River Foundation Angler Survey Reviewers:

Robert Brodberg, Ph.D. Office of Environmental Heath Hazard Assessment Janis Cook, Ph.D. Central Valley Regional Water Quality Control Board Fraser Shilling, Ph.D. University of California, Davis Alyce Ujihara, California Department of Public Health Michelle Wood, Central Valley Regional Water Quality Control Board

Recreational Trails Assessment Reviewers:

Wesley Nicks, Nevada County Department of Environmental Health Jill Pahl, Placer County Department of Environmental Health Tom Quinn, Forest Supervisor, Tahoe National Forest Randy Adams, CA Department of Toxic Substances Control John Hillenbrand, US Environmental Protection Agency