The Ore Hill Mine: Partnering on water quality and exploring hydrologic research

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1 The Ore Hill Mine: Partnering on water quality and exploring hydrologic research Aaron Johnson, Christopher Nealen, June Hammond Rowan, and Mark Green, Center for the Environment, Plymouth State University; and Sheela Johnson, White Mountain National Forest

2 Ore Hill Mine Warren, NH In White Mountain National Forest Thanks to Tim Buxton, Sheela Johnson, Clara Weloth, & Livia Crowley from WMNF Google Ore Hill Mine: white_mountain/projects/project s/ore_hill/ore_hill.html

3 Ore Hill Mine History 48 foot wide Ore Hill vein discovered by landowner, Mr. True Merrill, in Operated intermittently by various operators from 1834 to 1915 for lead, copper, zinc, and silver. Mine production est. 50,000 to100,000 tons. Major period of mining at the site started in 1889 when the mine was run by the Warren Zinc Company and shaft was deepened to 180 feet. Devastating fire in 1891, but operations continued. 35 men were employed at the mine at one time. Mine abandoned in Several piles of tailings & pile of waste rock left on site. Small drainage with poor water quality ran through the site &impacted water quality & aquatic species downstream in Ore Hill brook.

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6 Federal Ownership 1937: ½ of mine site acquired by USFS White Mountain National Forest. 1962: USFS planted red pine on the site, few trees survived. 1979: National Park Service acquired portion of site for the Appalachian Trail corridor consolidating federal ownership. AT rerouted. 1984: USFS & NPS recontoured the tailings piles, capped area with a thin layer of limestone & topsoil, & seeded area. 1988: on site surface water flow was diverted, channels were lined with limestone. 2000: Several acidic seeps had appeared. Grassed soil cap on tailings area was failing. Surface water at & below the site exceeded background & state water quality criteria for several metals.

7 USFS Action USFS completed necessary studies and reports to determine what to do Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) Goal: reclaim site to reduce contamination of surface water. USFS reclaimed site in 2006 under its CERCLA authority. Tailings and waste rock excavated & placed in repository. Expected to reduce metals movement from the materials by 90%. Treatment of the tailings and waste rock with a phosphate approach was expected to reduce metals in waters passing through the reposited material by additional 95% for the long term (100+years). Overall reduction of dissolved metals leaving the site of more than 95% was expected from the Removal Action. Bio reactor added in 2009 to additionally treat water

8 Ore Hill

9 WMNF & PSU CFE Partnership Starting in 2006: WMNF partnered with the Plymouth State University (PSU) Center for the Environment (CFE) to monitor water quality changes related to work at the site. CFE involved in monitoring surface water quality at the mine excavation area & downstream in Ore Hill Brook. Samples analyzed for >30 parameters: standard field measurements ~20 metals anions such as chloride, sulfate, and phosphate Involved several PSU students, faculty, & staff A unique approach has led to some unique findings

10 Sampling Design Frequency: 2006 every 6 weeks Later 4 samples/year Testing for: ph, Conductivity, Oxidation Reduction Potential Water samples for metals Designed to assess: Effectiveness of remediation actions Impact on Ore Hill Brook Sources of impairment

11 Expanding the Studies Student Involvement: Is the adit the major source of metals in surface water? How effectively are metals transported downstream?

12 Bioreactor Inflow Installed in 2009 Not well studied in cold climate, so opportunity to monitor bioreactor in cold climate Open Limestone Channel Substrate with sulfatereducing bacteria Outflow Constructed Wetlands

13 After 2006 Action

14 After 2009 Action Bioreactor Removal Efficiency (Outflow/Inflow) Water leaving the site has improved Sample Date Cadmium Copper Lead Zinc Average 93.31% 90.12% 65.09% 93.88%

15 Impact on Ore Hill Brook Water in Ore Hill Brook has improved modestly Overall Site Reductions Before SRB After SRB Cadmium 66.63% 93.32% Copper 88.31% 92.89% Lead 96.15% 96.50% Zinc 80.32% 92.42%

16 What s Going On?

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18 Graduate Student Involvement Analytical involvement Downstream transport of metals Different flows waterdata.usgs.gov

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20 Graduate Student Involvement cont. Project is related to my thesis Aluminum mobilization in harvested forests

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22 Graduate Student Involvement Cont. What are the mechanisms involved shaping the trends? Pore water ground water interactions Particulate flushing Stream sediment particulate interactions

23 Graduate Student Involvement Cont. Benefits of involvement Site management Real world experience Use of available data Model for my thesis

24 Conclusion This partnership is effectively solving the partner needs. Provides information for environmental reporting Partnership also produces novel outcomes by including an academic lens Going beyond the monitoring to pursue some of our curiosities: Groundwater bypass of the bioreactor Downstream transport of metals is not very efficient and changes with site wetness Gaining new understanding of the site and mine remediation projects