U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Navajo Abandoned Uranium Mine Site Screen Report This form is for use at the site of abandoned uranium mines (AUM) located on Navajo Nation lands. Applicable sites include all mine and mine features that have or have not undergone reclamation by the Navajo Abandoned Mine Lands Reclamation Program, including features, adits, pits and waste piles. Applicable sites also include all AUM sites listed in the USEPA CERCLIS database, all sites listed in the 2008 AUM GIS Report issued by USACOE and USEPA, all AUM sites on allotment lands associated with the Navajo Nation, and any and all AUM sites not listed in any database located on Navajo lands. Reconnaissance of any sites located on lands adjacent to Navajo lands that may be impacting Navajo lands will need to be coordinated with the authorities appropriate to those lands. The purpose of the form is to ascertain the status and location of the identified A UM site, and record all immediate site information associated with the mine site. Decisions and recommendations on what additional steps are needed will be provided on a separate document. Mine Name: Charles Huskon No. 7 (MP-357) Mine ID: 172 Navajo AUM Western Region Prepared by: Weston Solutions, Inc. Contract: W91238-06-F-0083 20074.063.017.0020 August 2011 Charles Huskon No. 7 (MP-357); Mine ID# 172 1 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part I Site Identification, Location and Status Site Names and ID numbers as applicable Mine ID: 172 Map ID: W14 CERCLIS: NNN000909226 Navajo Abandoned Mine Land Reclamation Program: NA-0113 Local name / Aliases: Charles Huskon #7 MP. #357 Chapter and local area: Bodaway / Gap County: Coconino State: Arizona Lat/Long: 36.1228195105N/-111.405157633 W Nearby road and highway: Indian Route 6134 Local Post Office: Tuba City, AZ Surface Land Status: check one or more and provide ownership and contact information below Tribal Trust Land ^ Public lands Q Private Q Tribal Fee Land Q Bureau of Land Mgmt Q Allotment Q State O Fee land Q Subsurface Mineral Rights: No information on subsurface mineral rights ownership was found in the EPA/AUM Database. Claim and operator information: The mine surface land status is classified as Tribal Trust Land. Historical documents identified the operator of the mine as Arrowhead Uranium Company in 1953, and Rare Metals Corporation of America from 1956 to 1958. No additional historical ownership / lease information was identified in the EPA / AUM database. Number of residential structures within 200 feet of mine: None Charles Huskon No. 7 (MP-357); Mine ID# 172 2 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part II Summary of Radiological Readings Mine ID: 172 Highest gamma radiation measurement: 105,814 counts per minute (cpm) Background Average: 18,044 cpm Two Times Background: 36,088 cpm Describe any other radiological measurements: A total of 4,140 gamma radiation measurements were collected from the mine site, ranging from 11,923 cpm to 105,814 cpm. Measurements collected in the vicinity of the reclamation areas were found at a maximum level of approximately 60,000 cpm. The measurements are represented in Figures 1 and 2. Distribution Chart and Statistics: Site Gamma Radiation Statistics Number of Readings 4,140 Minimum (cpm) 11,923 Maximum (cpm) 105,814 Mean (cpm) 22,214 Median (cpm) 19,986 Standard Deviation 8,253 Site Gamma Radiation Distribution 0> fit ¦a 500 000 500 000 500 000 500 0 < 10K 10K - 25K- 50K - 100K- 250K- 500K- 25K 50K 100K 250K 500K 1,000K Counts Per Minute (q)in) H < 10K H 10K-25K U25K-50K U50K-100K H100K-250K H250K-500K ¦ 500K - 1,000K Charles Huskon No. 7 (MP-357); Mine ID# 172 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part III Status of Reclamation and Mine Waste Mine ID: 172 The following information was obtained from the Navajo Abandoned Mine Land Reclamation Program (NAMLRP) Point Features Database: NAMLRP Status of the mine site: Reclaimed: Yes Waste Pile onsite: No NAMLRP Project Number: NA-0113 NAMLRP Mine features: 1 Rim Strip / Pit The following information was obtained from field observations collected during the 2011 site screening: Provide description and status of all mine sites and features at site. Include all waste piles, adits, pits and other features, and indicate whether they are open, closed, covered, capped, buried or unreclaimed. Indicate approximate size, shape and extent, including description of any reclamation caps. Note condition of all caps. Observed reclamation work and status: Adits: None observed Waste Piles: None observed Pits: None observed Shafts: None observed Other Debris and Mine Features: 4 reclamation caps: Cap 1, Cap 2, and Cap 3 - comprised of 600'x300'xl2' tan sandy area with little vegetation in southeast corner of site; Cap 4 - 450'x250'xl0' irregular shape split by wide drainage in northwest portion of site Charles Huskon No. 7 (MP-357); Mine ID# 172 4 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part IV Site Observations and Environs Observed Residential Structures (number and human habitation status of structures at the following distances from the mine site): 0 to 200 feet: None observed 200 feet to 0.25 mile: None observed Observed Public or Commercial Structures (schools, clinics, Chapter Houses, places of business and any other structures used by members of the community at the following distances from the mine site): 0 to 200 feet: None observed 200 feet to 0.25 mile: None observed Levels measured around the perimeter(s) of the identified structure(s): None Observed Water Sources (number and type of wells and surface water sources that are potentially used for human consumption at the following distances from the mine site): 0 to 0.25 miles: None observed 0.25 miles to 4 miles: None observed Sensitive Environments (all sensitive environments located within visible range of the mine site, including: wetlands, endangered species, habitats and approximate locations of sites that may be under protection of the government of the Navajo Nation): The site in located within a wash area which may contain seasonal tributaries to the Little Colorado River Known Site History (information from interviews with Chapter officials and residents and database review, includes: mine ownership, type of mining operation, period of operation, known amount of production, and any other information provided): The Charles Huskon No. 7 (MP-3 57) mine claim consists of an area of 108,647.74 m2 The mine surface land status is classified as Tribal Trust Land. Historical documents identified the operator of the mine as Arrowhead Uranium Company in 1953, and Rare Metals Corporation of America from 1956 to 1958. No additional historical ownership / lease information was identified in the EPA / AUM database. Charles Huskon No. 7 (MP-357); Mine ID# 172 5 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part V Response Action Summary Summary of Evaluation Factors: Accessibility: Was the mine easily accessible to potential human activity? Yes Radiological Measurements: Were any gamma radiation measurements collected at the mine greater than two times the site-specific background levels? Yes Waste Piles: Were any unreclaimed waste piles observed at the mine with gamma radiation measurements greater than two times the site-specific background levels? No Structures: Were any structures observed within 200 feet of the mine? No Potential Drinking Water Sources: Were any potential drinking water sources observed within 4 miles of the mine? No Reclamation: Was the mine reported to be previously reclaimed, or did the mine appear to be reclaimed? Yes Charles Huskon No. 7 (MP-357); Mine ID# 172 6 August 2011 ------- ¦G.S. Environmental Protection Agency Region IX, San Francisco Part VI Photos Navajo AtlM Project Photo 1: Mine Site #172; Reclamation area Photo 2: Mine Site #172; Reclamation area Charles Huskon:Np. 7 (MP-357); Mine ID# 172 7 August 2011 ------- ¦G.S. Environmental Protection Agency Region IX, San Francisco Navajo AtlM Project Photo 4: Mine Site #172 Charles Huskon:Np. 7 (MP-357); Mine ID# 172 8 August 2011 ------- U.S. Environmental Protection Agency Region IX, San Francisco Navajo AUM Project Part VII Contacts Reports and Information Name: Eugene Esplain Title or official role (if any): Navajo EPA Superfund Program Telephone number: (928) 871-7331 Address: PO Box 2946. Window Rock. AZ 86515 Information provided: Lead Regulatory Agency Name: Title or official role (if any): Telephone number: Information provided: Name: Title or official role (if any): Telephone number: Address: Information provided: Charles Huskon No. 7 (MP-357); Mine ID# 172 9 August 2011 ------- Figure 1 - Gamma Radiation Measurements, Above Two Times Background Charles Huskon No. 7 (MP-357) (172) Bodaway / Gap Chapter, Navajo Nation [CJnaEl^HjuskonlNoW^ M ? \ Mine Site Boundary General Slope Direction Observed Reclamation Feature Legend Gamma Radiation Measurements • < 2X Backgourid • > 2X Background Observed Waste Pile Measured as counts per minute (cpm) Average background 18,044 cpm %%%/ Steep Grade ! Feet 300 ------- Figure 2 - Gamma Radiation Measurements Charles Huskon No. 7 (MP-357) (172) Bodaway I Gap Chapter, Navajo Nation * * u.. Gamma Radiation Measurements • 0- 10,000 cpm • 10,000 - 25,000 cpm 25,000 - 50,000 cpm 50,000 - 100,000 cpm • 100,000 -250,000 cpm • 250,000 -500,000 cpm • 500,000 - 1,000,000 cpm Steep Grade Measured as counts per minute (cpm) Average background 18,044 cpm Mine Site Boundary General Slope Direction Observed Reclamation Feature Observed Waste Pile '-Jt ,'JJN -iJjL I Feet 300 ------- |