SLAC Study Helps Explain Why Uranium Persists in Groundwater at Former Mining Sites

Decades after a uranium mine is shuttered, the radioactive element can still persist in groundwater at the site, despite cleanup efforts.

A recent study led by scientists at the Department of Energy’s SLAC National Accelerator Laboratory helps describe how the contaminant cycles through the environment at former uranium mining sites and why it can be difficult to remove. Contrary to assumptions that have been used for modeling uranium behavior, researchers found the contaminant binds to organic matter in sediments. The findings provide more accurate information for monitoring and remediation at the sites.

The results were published in the Proceedings of the National Academy of Sciences.

In 2014, researchers at SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) began collaborating with the DOE Office of Legacy Management, which handles contaminated sites associated with the legacy of DOE’s nuclear energy and weapons production activities. Through projects associated with the Uranium Mill Tailings Radiation Control Act, the DOE remediated 22 sites in Colorado, Wyoming and New Mexico where uranium had been extracted and processed during the 1940s to 1970s.

LED lighting could have major impact on wildlife

LED street lighting can be tailored to reduce its impacts on the environment, according to new research by the University of Exeter.

The UK-based study found predatory spiders and beetles were drawn to grassland patches lit by LED lighting at night, but the number of species affected was markedly reduced when the lights were dimmed by 50% and switched off between midnight and 4am.

Study tracks vegetation resilience to salvage logging after severe wildfire

Nearly a decade after being logged, vegetation in forested areas severely burned by California's Cone Fire in 2002 was relatively similar to areas untouched by logging equipment. The findings of a U.S. Forest Service study shed light on how vegetation responds to severe wildfire and whether further disturbances from logging affect regrowth.

Human activity degrades Natural World Heritage Sites

A report published in the journal Biological Conservation finds that recent increases in human pressure and forest loss are causing the degradation of over 100 Natural World Heritage Sites (NWHS) globally.

China to protect areas of high ecological importance identified by Stanford researchers

China leads the world in greenhouse gas emissions. Its biggest cities are shrouded in smog. And the country’s population is 1.4 billion people and growing. At least to the rest of the world, China isn’t known as a leader in environmental mindfulness.

Flipping the switch on ammonia production

Nearly a century ago, German chemist Fritz Haber won the Nobel Prize in Chemistry for a process to generate ammonia from hydrogen and nitrogen gases. The process, still in use today, ushered in a revolution in agriculture, but now consumes around one percent of the world’s energy to achieve the high pressures and temperatures that drive the chemical reactions to produce ammonia.

Today, University of Utah chemists publish a different method, using enzymes derived from nature, that generates ammonia at room temperature. As a bonus, the reaction generates a small electrical current. The method is published in Angewandte Chemie International Edition.

Change in astronaut's gut bacteria attributed to spaceflight

Northwestern University researchers studying the gut bacteria of Scott and Mark Kelly, NASA astronauts and identical twin brothers, as part of a unique human study have found that changes to certain gut “bugs” occur in space.

The Northwestern team is one of 10 NASA-funded research groups studying the Kelly twins to learn how living in space for a long period of time -- such as a mission to Mars -- affects the human body. While Scott spent nearly a year in space, his brother, Mark, remained on Earth, as a ground-based control.

A new study confirms: Pregnant women should avoid liquorice

Liquorice and its natural sweetener, glycyrrhizin, can have long-term harmful effects on the development of the fetus.

Mathematically optimizing traffic lights in road intersections

Traffic modeling has been of interest to mathematicians since the 1950s. Research in the area has only grown as road traffic control presents an ever-increasing problem. 

Generally, models for traffic flow in road networks are time-dependent and continuous, that is, they describe traffic by a continuum rather than as individual drivers or cars. These macroscopic models describe the temporal and spatial evolution of traffic density without predicting traffic patterns of individuals.  In addition to macroscopic models based on continuous densities, microscopic approaches like particle models or cellular automata are also used to model traffic.

Jekyll and Hyde cells: their role in brain injury and disease revealed

New research has shown how normally helpful brain cells can turn rogue and kill off other brain cells following injury or disease.Astrocytes have long been implicated in the pathology of a range of human neurodegenerative diseases or injuries including Alzheimer's, Huntington’s Parkinson’s disease, brain trauma and spinal cord injury.