The origin of elevated radium-226 in groundwater beneath a sanitary landfill at the Savannah River Site (SRS) was investigated. Nearly one hundred monitoring wells are developed in the Steed Pond Aquifer (SPA), which consists of 100-150 ft of Coastal Plain sand, iron oxides, and minor clay. Wells screened in the upper and middle portions of the aquifer have average Ra-226 between 0.5 and 2.5 pCi/L, and average pHs above 4.7. However, wells screened near the base of the aquifer exhibit higher average Ra-226 concentrations of 2.5 to 4.6 pCi/L, with some measurements exceeding the MCL of 5 pCi/L, and show average pHs of 4.1 to 4.7. These wells are not downgradient of the landfill, and are not impacted by landfill leachate. The Crouch Branch Confining Unit (CBCU) underlies the aquifer, and is composed partly of reduced gray/brown clay with lignite and authigenic pyrite. Gamma ray logs show that the SPA has low gamma counts, but the CBCU is consistently elevated. Groundwater with high radium/low pH also contains elevated sulfate concentrations. pH calculations indicate that sulfate is in the form of sulfuric acid. A model for the origin of elevated Ra-226 levels in deeper SPA wells envisions infiltration of oxygenated SPA …

Mineral County in west-central Nevada has been host to the Hawthorne Army Depot for decades. The county contains the community of Hawthorne, which is where the Depot is located, as well as a handful of smaller communities. The county's western boundary line also serves as the state border between California and Nevada. Hawthorne is the county seat and lies 130 miles southeast of the metropolitan area of RenoISparks, Nevada. It is approximately 3 10 miles northwest of Las Vegas, Nevada.

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.

Iodine is a biophilic element, with one stable isotope, {sup 127}I, and one long-lived radioisotope, {sup 129}I, which originates in the surface environment almost entirely from anthropogenic activities such as nuclear fuel reprocessing. Very few studies have evaluated the geochemical behavior of iodine isotopes in the subsurface. The concentrations of {sup 129}I and {sup 127}I were measured in wells fed by a series of artificial recharge ponds in the Forebay Area of the Orange County groundwater basin (California, USA) to evaluate their potential use as hydrological tracers. To substantiate interpretation of {sup 129}I and {sup 127}I concentration data, the aquifer system was evaluated using literature values of aquifer water mass age based on {sup 3}H/{sup 3}He, Xenon and {delta}{sup 18}O tracer data, as well as time-series data of Santa Ana River flow rates over the past decade. The aquifer data demonstrate the nearly conservative behavior of {sup 129}I, with {sup 129}I/{sup 127}I ratios likely reflecting variations in source functions as well as climatic conditions, and with inferred particle-water partition coefficients (K{sub d}) of 0.1 cm{sup 3} g{sup -1} or less.

Weekly newspaper from Rio Grande City, Texas that includes local, state and national news along with extensive advertising.

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

Weekly student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.

Weekly newspaper from Comanche, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Dublin, Texas that includes local, state, and national news along with advertising.

This report documents research conducted by the RCS Project to update the record of decision for the 300-FF-5 Operable Unit on the Hanford Site.

Weekly newspaper from Holliday, Texas that includes local, state, and national news along with advertising.

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.

This report discusses about energy tax policy. U.S energy tax policy promoted the supply of oil and gas but witnessed significant cutback, imposition of new excise taxes on oil and introduction of numerous tax preferences for energy conservation.

Weekly newspaper from Yoakum, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.

Weekly newspaper from Goldthwaite, Texas that includes local, state, and national news along with extensive advertising.

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Goldthwaite, Texas that includes local, state, and national news along with extensive advertising.

The bacterium Caulobacter crescentus and related stalkbacterial species are known for their distinctive ability to live in lownutrient environments, a characteristic of most heavy metal contaminatedsites. Caulobacter crescentus is a model organism for studying cell cycleregulation with well developed genetics. We have identified the pathwaysresponding to heavy metal toxicity in C. crescentus to provide insightsfor possible application of Caulobacter to environmental restoration. Weexposed C. crescentus cells to four heavy metals (chromium, cadmium,selenium and uranium) and analyzed genome wide transcriptional activitiespost exposure using a Affymetrix GeneChip microarray. C. crescentusshowed surprisingly high tolerance to uranium, a possible mechanism forwhich may be formation of extracellular calcium-uranium-phosphateprecipitates. The principal response to these metals was protectionagainst oxidative stress (up-regulation of manganese-dependent superoxidedismutase, sodA). Glutathione S-transferase, thioredoxin, glutaredoxinsand DNA repair enzymes responded most strongly to cadmium and chromate.The cadmium and chromium stress response also focused on reducing theintracellular metal concentration, with multiple efflux pumps employed toremove cadmium while a sulfate transporter was down-regulated to reducenon-specific uptake of chromium. Membrane proteins were also up-regulatedin response to most of the metals tested. A two-component signaltransduction system involved in the uranium response was identified.Several differentially regulated transcripts from regions previously notknown to encode proteins were identified, demonstrating the advantage …

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Semiweekly newspaper from Sealy, Texas that includes local, state, and national news along with advertising.