Cristina González-Maddux Institute for Tribal Environmental Professionals Northern Arizona University

 Background  Mining impacts on surficial composition  Other industrial influences and TRI queries  Dust and particulate matter  Human health concerns  Research  Project 1: Shiprock, New Mexico – fine particulate study, focus on enrichment factor  Project 2: Fry Canyon, Utah – mine waste bioaccessibility  Summary

 Uranium reserves in the Four Corners: Northern Arizona, Marysvale, Paradox Basin, Sand Wash, Front Range, Tallahassee Creek, Marshall Pass, Grants Mineral Belt  Of ~4,000 mine site proxies in the USGS MAS/MILS database, ~3,000 are located in the Four Corners states Map source: Uranium Location Database Compilation. Technical Report EPA-402-R

“The Navajo Abandoned Mine Lands Reclamation Program (NAMLRP) identified more than 1,032 abandoned uranium mine sites. As of 2005, 913 sites have been reclaimed (p. 224).” - US EPA TENORM Technical Report, Vol. 1 (2006)

 Overburden  Protore  Barren or waste rock  Drill cuttings  Waste treatment sludge

Underground and surface mines:  Waste rock (overburden pile)  Protore piles  Ore stockpiles

Tailings dam 1973Heap-leach pile 2010, (abandoned in 1968)

 EPA calculations based on 2000 U.S. Census data and the Basins MAS/MILS database State Population (within 5 miles of an AUM) Arizona 12,160 New Mexico 84,869 Colorado 518,357 Utah 22,376 Total 637,762

 TRI chemical release reports were reviewed for metals emissions in order to establish potential local or regional industrial influences on enrichment  Fugitive and point source industrial air emissions were compiled for both San Juan County, New Mexico as well as for all surrounding counties:  Rio Arriba County, NM, Sandoval County, NM, McKinley County, NM, Montezuma County, CO, La Plata County, CO, Apache County, AZ, and San Juan County, UT.

Primarily soil dust constituents: Al, Si, S, K, Ca, Fe Trace metals also present

 Deleterious metals associated with uranium mine waste  vanadium (V), copper (Cu), arsenic (As), uranium (U),  other trace elements and trace metals (Sb, Se, Pb, Cr, Zn)  Human exposure pathways  Ingestion  Inhalation  Dermal penetration

The health effects associated with oral or dermal exposure to natural and depleted uranium appear to be solely chemical in nature and not radiological, while those from inhalation exposure may also include a slight radiological component, especially if the exposure is protracted. - ATSDR toxicological profile for uranium, May 2011

Composition of fine particulate matter (PM 2.5 ) downwind of AUMs

 Collect samples of PM 2.5 dust downwind of AUMs  Identify metals in PM 2.5  Compare observed and expected concentrations using enrichment factor [EF] analysis

 Collection  10 samples collected over 3 months (2009 and 2010)  PM 2.5 monitor (Met One)  Teflon filters (47mm)  96 h/sample  37 m 3 of air sampled per filter (6.7 LPM)  Analysis  Gravimetric (± 0.1 ng)  XRF spectrometry – major soil elements (Chester LabNet)  ICP-MS – trace metals (ASU)

, 7Air sampling location UMTRA site Climax Transfer Station 1. Four Corners Generating Station, APS – coal fired power plant; 2. BHP Navajo Coal Co. – coal mining operation; 3. BHP Navajo Coal Co. – coal mining operation; 4. San Juan Refining Co. (A.K.A. Western Refining SW) – petroleum refinery; 5. Coastal Chemical Co., L.L.C. – chemical manufacturer (incl. petrochemicals); 6. San Juan Coal Co., San Juan Mine – coal mining operation; 7. San Juan Generating Station, PNM – coal fired power plant.

Industry key: EU = electric utilities, CM = coal mining, P = petroleum, SCG = Stone/Clay/Glass A Combined results for San Juan county, NM and all surrounding counties: Rio Arriba county, NM, Sandoval county, NM, McKinley county, NM, Apache county, AZ, San Juan county, UT, Montezuma county, CO and La Plata county, CO. B Includes pounds of toxins released for both elemental compounds and element.

 Average concentration 10 µg/m 3  U.S. EPA 24-h fine particulate standard 35 µg/m 3

 6 soil elements were most abundant: Al, Si, S, K, Ca, Fe (range µg/m 3 )  24 trace metals were detected ( ng/m 3 )  11 trace elements were enriched in both major sampling periods (Winter 2009, 2010) Enrichment Factor analysis EF (X) = ([X sample /Al sample ] / [X crust /Al crust ])

ElementMax EFPotential sources AUMMiningIndustry Selenium (Se) 37,632 ✔✔ Bromine (Br) 3,113 ✔ Sulfur (S) 1,704 ✔ Antimony (Sb) 1,314 ✔✔ Boron (B) 881 ✔ Bismuth (Bi) 655 ✔✔ Tin (Sn) 500 ✔✔ Cadmium (Cd) 381 ✔ Nickel (Ni) 189 ✔ Lead (Pb) 81 ✔✔ Copper (Cu) 52 ✔✔ Zinc (Zn) 44 ✔✔

ElementMax EFPossible sources AUMsMining Assoc.Industry Uranium (U) 18 ✔✔ Cobalt (Co) 13 ✔ Barium (Ba) 9 ✔✔ Vanadium (V) 6 ✔✔ Manganese (Mn) 5 ✔ Strontium (Sr) 2 ✔ Beryllium (Be) 2 ✔✔

 San Juan County (NM) airshed is burdened by enriched concentrations of several deleterious and toxic metals  Federal particulate standards were not exceeded at any point during the study  Probable contribution to toxic metal enrichment from industrial sources  No data to definitively link AUM metals to fine particulate composition (additional research needed to evaluate)

 Shiprock served as excellent study site  It is subject to regional air quality issues that may have human health implications based metal enrichment in fine particulate  Additional research is required to determine the true airshed burden from abandoned and active mine sites  Air dispersion modeling  Isotopic analysis  Currently investigating the role of mining interference factor