1. ASARCO Tailings Violations Pima County Department of Environmental Quality

2. Background ASARCO operates an open pit copper mine that consists of: ASARCO operates an open pit copper mine that consists of: Mining Mining Crushing Crushing Grinding Grinding Concentrating Concentrating Operations began in 1961 Operations began in 1961 ASARCO has a a Class I (Title V) permit for PM 10 emissions ASARCO has a a Class I (Title V) permit for PM 10 emissions

3. Class I (Title V ) Permit ASARCO is subject to New Source Performance Standards (NSPS) for Metallic Mineral Processing Plant ASARCO is subject to New Source Performance Standards (NSPS) for Metallic Mineral Processing Plant Emissions consists of point source from milling operation and fugitive from the pit, haul roads and tailings Emissions consists of point source from milling operation and fugitive from the pit, haul roads and tailings Tailings subject to: Tailings subject to: Opacity limit of 20% Opacity limit of 20% Reasonable and necessary precautions must be taken to prevent excess emissions from crossing property boundary Reasonable and necessary precautions must be taken to prevent excess emissions from crossing property boundary Tailings must be smeared every 60 days during berm building Tailings must be smeared every 60 days during berm building

5. Berm Building ASARCO began berm building to raise the side of tailings dam #8 in September 2009 ASARCO began berm building to raise the side of tailings dam #8 in September 2009 PDEQ began receiving complaints in October 2009 PDEQ began receiving complaints in October 2009 Inspections conducted on October 21 and 27 resulted in opportunity to correct. Opacity reading of 29% observed by PDEQ inspector Inspections conducted on October 21 and 27 resulted in opportunity to correct. Opacity reading of 29% observed by PDEQ inspector

13. Excess Emission Reports November 12 th ASARCO reported excess emissions of 61% opacity to PDEQ November 12 th ASARCO reported excess emissions of 61% opacity to PDEQ PDEQ conducted an inspection on November 12 th. No opacity readings taken by PDEQ due to position of the sun. Emission observed crossing the property boundary PDEQ conducted an inspection on November 12 th. No opacity readings taken by PDEQ due to position of the sun. Emission observed crossing the property boundary Inspection and excess emission results in Notice of Violation Inspection and excess emission results in Notice of Violation

17. Wind Event of December 22 Weather forecast called for high winds in the afternoon Weather forecast called for high winds in the afternoon PDEQ conducted an inspection in early afternoon PDEQ conducted an inspection in early afternoon Excessive emission observed with opacity reading of 83% by PDEQ inspector. ASARCO records a 75% opacity reading and self reports Excessive emission observed with opacity reading of 83% by PDEQ inspector. ASARCO records a 75% opacity reading and self reports ASARCO begins applying wet tailings ASARCO begins applying wet tailings NOV issued for violations NOV issued for violations

24. January 7, 2010 Inspection PDEQ conducts follow up inspection on January 7, 2010 PDEQ conducts follow up inspection on January 7, 2010 Approximately 50 % of tailing dams covered in wet tailings Approximately 50 % of tailing dams covered in wet tailings ASARCO continues to berm build. Anticipate completion towards the end of January ASARCO continues to berm build. Anticipate completion towards the end of January Part of tailings still dry Part of tailings still dry

29. Tailings Sampling PDEQ collected samples of the mine tailings, surrounding soil, and material from an individual's yard PDEQ collected samples of the mine tailings, surrounding soil, and material from an individual's yard Samples were collected to address concerns from the community as to what is in the ASARCO tailings Samples were collected to address concerns from the community as to what is in the ASARCO tailings Samples analyzed by EPA lab for constituents recommended by Dr. Betterton and Dr. Maier from the U of A Samples analyzed by EPA lab for constituents recommended by Dr. Betterton and Dr. Maier from the U of A

30. Sample Results The sample results were reviewed by Dr. Betterton and Dr. Maier. They concluded that metal concentrations were not elevated above background concentrations. The sample results were reviewed by Dr. Betterton and Dr. Maier. They concluded that metal concentrations were not elevated above background concentrations. Material taken from a resident’s yard was found to be from the tailings based upon its composition. Material taken from a resident’s yard was found to be from the tailings based upon its composition. The tailings were not found to be toxic. However, small size fraction poses a health risk The tailings were not found to be toxic. However, small size fraction poses a health risk

31. ASARCO Response ASARCO Responded to the NOV and disagrees they were in violation. ASARCO Responded to the NOV and disagrees they were in violation. ASARCO asserts they were taking all reasonable precautions ASARCO asserts they were taking all reasonable precautions ASARCO has developed additional berm building procedures that include: ASARCO has developed additional berm building procedures that include: Use of additional equipment to accelerate the time it takes to do berm building Use of additional equipment to accelerate the time it takes to do berm building Use of specialized equipment to apply dust suppressants Use of specialized equipment to apply dust suppressants Breaking the berm into segments so tailings can be applied quicker Breaking the berm into segments so tailings can be applied quicker

32. Enforcement Status PDEQ has been working with the County Attorney and EPA regarding appropriate penalties. PDEQ has been working with the County Attorney and EPA regarding appropriate penalties. PDEQ has requested additional information from ASARCO regarding their berm building process that led to the violations. PDEQ is awaiting ASARCO’s response PDEQ has requested additional information from ASARCO regarding their berm building process that led to the violations. PDEQ is awaiting ASARCO’s response PDEQ and ASARCO will be engaging in penalty discussions in June PDEQ and ASARCO will be engaging in penalty discussions in June EPA has issued an information request to ASARCO and is currently awaiting a response EPA has issued an information request to ASARCO and is currently awaiting a response

33. ASARCO Tailings Activities ASARCO is using tailings dam 7 and 8 ASARCO is using tailings dam 7 and 8 Berm building has begun tailings dam 4 Berm building has begun tailings dam 4 ASARCO is working with the Indian Nation of closure and capping of tailings dam 1, 2, and 3. These tailings dam are located in the nation and are not under PDEQ’s jurisdiction ASARCO is working with the Indian Nation of closure and capping of tailings dam 1, 2, and 3. These tailings dam are located in the nation and are not under PDEQ’s jurisdiction

35. April 2010 NOV PDEQ has conducted 14 inspections at ASARCO since January 2010 PDEQ has conducted 14 inspections at ASARCO since January 2010 PDEQ issued a NOV in April for opacity violations at tailings dam 4. PDEQ issued a NOV in April for opacity violations at tailings dam 4. ASARCO failed to take precautions to prevent wind blown tailings ASARCO failed to take precautions to prevent wind blown tailings PDEQ is awaiting ASARCO’s response to this recent NOV PDEQ is awaiting ASARCO’s response to this recent NOV

38. Information Information on ASARCO mine tailings can be found on PDEQ website. Information on ASARCO mine tailings can be found on PDEQ website. www.deq.pima.gov www.deq.pima.gov www.deq.pima.gov PDEQ Contacts PDEQ Contacts Beth Gorman, Communications Manager 243-7446 Beth Gorman, Communications Manager 243-7446 Richard Grimaldi, Deputy Director 243-7363 Richard Grimaldi, Deputy Director 243-7363