site assessment at old churchrock mine, churchrock chapter
TRANSCRIPT
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Site Assessment atSite Assessment atOld Old ChurchrockChurchrock Mine, Mine,ChurchrockChurchrock Chapter Chapter
Conducted by Staff of Navajo EPA-Conducted by Staff of Navajo EPA-Superfund Superfund Program and SRICProgram and SRICAug. 2, 2006Aug. 2, 2006following runoff in unnamed arroyo onfollowing runoff in unnamed arroyo on7/31/06 or 8/1/067/31/06 or 8/1/06
prepared by Chris prepared by Chris ShueyShuey, SRIC, SRIC8/21/06; rev. 9/15/06, 5/11/078/21/06; rev. 9/15/06, 5/11/07
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Site HistorySite History• Location: T16N, R16W, Sec. 17 (NE-1/4), McKinley
County, NM; Church Rock Chapter, Navajo Nation• Land Status: Navajo Tribal Trust surface, privately owned
mineral estate; active grazing on Sec. 17• 1959: Surface use agreement between Santa Fe Railway
and Navajo Tribe• 1960-62: Underground mine in Dakota SS, operated by
Phillips Petroleum Co.• 1977-1983: Underground mine in Westwater Canyon SS,
operated by United Nuclear Corp.• 1992-present: Proposed ISL mine, Hydro Resources, Inc.
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Cattle Canyon
Cattle Canyon
Unnamed arroyo onUnnamed arroyo onwest side of mine sitewest side of mine site
Old Church Rock Mine
SR 566
Area of mud flat afterArea of mud flat after8/1/06 flood event8/1/06 flood event
Old Churchrock Mine Site,Churchrock Chapter, Navajo Nation
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Evidence of Flood EventEvidence of Flood Event
Standing water, mud in arroyo
Corner fence postdislodged by flood
Mud flat at mouth of arroyo (here, below)
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Differences in SedimentDifferences in SedimentCharacteristicsCharacteristics
• Mine wastes, east side of arroyo (photo, upper right)– conglomeritic, gray-black color– white precipitate lenses on bank next to mine-water ponds
• Normal sediments, west bank of arroyo (photo, upper left)– ochre color, shaley
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Presence of Mine WastesPresence of Mine Wastes
Mining equipmentin arroyo next to
mine (left side)1 of 5 mine water pondsat OCRM site
Mine wasteon east side
of arroyo
Former uraniumworkers like ScottyBegay (left) havetestified aboutwaste disposalpractices at OCRM
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RadiologicalRadiologicalSurveySurvey• Reported by NNEPA-SF,
8/17/06• Background at mouth of
arroyo: 12-15 uR/hr• Gray-black material on
eastern arroyo bank, 50-75 uR/hr
• White precipitate inlayers on eastern bank,110-460 uR/hr
• West bank of arroyo: 20-30 uR/hr
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Old Old Churchrock Churchrock Mine site assessmentMine site assessmentAugust 2006August 2006
(Gamma radiation measurements made using Ludlum-19)(Gamma radiation measurements made using Ludlum-19)
Shaded area above approximate shape of muddelta at mouth of arroyo after flood event
Unnamed arroyo inSec. 8, T16N, R16W
Mining debris inarroyo: concrete,dirt, steel chute
Abandonedmine waterponds
420-460420-460 uR/hr
70-12070-120 uR/hr
15-3015-30 uR/hr
Sec. 9Sec. 8
Occupied home
King Grazing Permit Area(shaded)
Sealed mineshafts
Sec. 17 Sec. 16
Unnamed arroyo inSec. 17, T16N, R16W
Old Church Rock Mine Road
King Ranch (3occupied residences)
Section linesapproximate
State Route 566
IX building
• Max. 350350uR/hr in ‘87
• Max. 180180uR/hr in 2003
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Mining Debris in ArroyoMining Debris in Arroyo
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EnvironmentalEnvironmentalExposuresExposures
King GrazingPermit Area
HRI License AreaBoundary
Contour onbase of mesa
Old ChurchrockMine area
OCRM (Sec.17) mine waterponds
King Ranch,residences
Old Church Rock Mine(shaded oval, right;aerial below) in relationto King Ranch landsand homesites in yellowshaded area (right)
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Gamma rates>2x background(shown in red)indicatetransport ofresidual minewaste from OldChurch RockMine onto KingRanch land
CRUMPCRUMPGammaGammaRadiationRadiationAssessment,Assessment,20032003
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Epilogue:Epilogue:
Another Runoff Event, 9/6/06Another Runoff Event, 9/6/06
Arroyo was flowing (upper R and L) following afternoon stormon Sept. 6, 2006; mud flat at mouth of arroyo (bottom L)
measured about 300 m wide; 1-m wide boulder (bottom R) wasdeposited by early-August flood event.
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Epilogue II:Epilogue II:
New Radiological AssessmentNew Radiological Assessment
• Conducted by NNEPA-SF, March 2007 (photo)
• Navajo Nation concernedabout NRC’s decision in2006 reclassifying wastesat OCRM as“background radiation”
• Reclamation in limbo