Satellites track the Water Cycle on Planet Earth

 

Though the recent landing of the Perseverance Rover on Mars has drawn our attention, it is important to recall (or know) that NASA is also gathering data on our own planet, Earth. The latest research was published last week in the journal” Nature.” Using data gathered by NASA’s Ice, Cloud and land Elevation Satellite 2 (ICESat-2), launched in September 2018, and the older Landsat mission jointly overseen by NASA and the U.S. Geological Survey, this new research begins the investigation of mankind’s impact on freshwater resources and the planet’s water cycle.  

NASA scientists conducted the first global accounting of fluctuating water levels in Earth’s lakes and reservoirs. Though the scientists had not expected it, they found that reservoirs made up the majority of total variability of water storage despite the fact that natural lakes and ponds outnumber human-managed reservoirs by more than 24 to 1. The variability in reservoirs only makes sense, you build a reservoir when you need to store water for later; but the amount of fluctuation was controlled by human action is an indication of how much of the surface fresh water is being used by mankind. It will be interesting to see how droughts impact this number during a longer duration study.  

ICESat-2 gathers information by sending 10,000 laser light pulses  down to Earth every second. When reflected back to the satellite, those pulses deliver high-precision surface height measurements for every 28 inches along the satellite’s orbit. Using the trillions of data points collected, scientists can measure volume of Earth’s lakes and ponds over time. The scientists used the Landsat two-dimensional maps of bodies of water and their sizes, providing them with a comprehensive database of the world’s lakes, ponds, and reservoirs. Then, ICESat-2 added the third dimension – height of the water level.

The scientists found from season to season, the water level in Earth’s lakes and ponds that are natural and unmanaged fluctuate on average about 8.6 inches each year. However, the water level of human-managed reservoirs fluctuates on average nearly four times that amount – about 34 inches each year. Still the volume in human managed reservoirs has to exceed natural ponds and lakes by more than 6 to 1 for the majority of fluctuation to be attributed to human management.  

Understanding that variability and finding patterns in water management really shows how much we are altering the global hydrological cycle,” said Dr. Sarah Cooley, a remote sensing hydrologist at Stanford University in California, who led the research. “The impact of humans on water storage is much higher than we were anticipating.”

In natural lakes and ponds, water levels typically vary with the seasons. In reservoirs, however, managers influence that variation – often storing more water during rainy seasons and diverting it when it’s dry, which can exaggerate the natural seasonal variation, Cooley said.

Dr. Cooley and her colleagues found regional patterns as well – reservoirs vary the most in the Middle East, southern Africa, and the western United States, while the natural variation in lakes and ponds is more pronounced in tropical areas.

In the future the scientists will investigate how human activity and climate alters the availability of freshwater. As the ever-growing populations place more and more demands on freshwater, and climate change alters the way water moves through the hydrological cycle, studies like this can illuminate how water is being managed, Cooley said.

This data could eventually be used for better water management to maximize water availability as populations continue to grow and the climate continues to change.

For more information on ICESat-2, visit www.nasa.gov/icesat-2

To read the full report Human alteration of global surface water storage variability | Nature

Uranium Mining in Virginia a Threat to Our Water Resources

Last week the winter session of the Virginia General Assembly was called to order. Scheduled to be decided this winter is whether or not to lift a 30-year-old moratorium on uranium mining within the state. Senator John Watkins has introduced a proposal to require the state to draft uranium-mining regulations, essentially ending the 30 year moratorium on Uranium mining in the Commonwealth. Senator Watkins, from Powhatan and Senator Richard Saslaw, from Fairfax will carry the legislation in the Senate, and Delegate Jackson Miller, from Manassas, will introduce similar legislation in the House of Delegates. Now is the time to make your voice heard.

In 1978 a particularly rich deposit of Uranium was discovered at Cole's Hill in Pittsylvania County in south central Virginia. This was followed by a flurry of exploration for uranium deposits in Virginia. In 1982 the Commonwealth placed a moratorium on uranium mining. In recent years, as the price of uranium reached $140 around 2007, and two families living in the vicinity of Cole's Hill formed a company called Virginia Uranium, Inc. to begin exploring the uranium deposit once again. Though the uranium spot price has fallen to around $40, that is still more than twice the historical price, and Virginia Uranium and their supporters have called for the Virginia legislature to lift the uranium mining moratorium for now just on Cole's Hill. As this was all percolating in state politics, in 2009 the Virginia Coal and Energy Commission requested that the National Research Council convene an independent committee of experts to review all the literature and develop a report to identify the scientific, environmental, human health and safety, and regulatory aspects of mining and processing Virginia’s uranium resources. In addition, Fairfax Water commissioned a white paper on uranium mining and ended up with the Fairfax County Water Authority opposing uranium mining in Virginia and supporting the continuation of the moratorium on uranium mining in the Commonwealth.  

After reviewing these reports and as a voting member of the Potomac Watershed Roundtable I voted with the majority to maintain the moratorium on uranium mining. The Virginia Association of Soil and Water Conservation Districts with which I am also affiliated (through my volunteer work at the PWSWCD) also supports maintaining the moratorium. The Virginia Municipal League, the Virginia Association of Counties, the Virginia Farm Bureau, the Fauquier Water Authority, and local governments from Halifax and Virginia Beach, oppose lifting the ban. Last week Lt. Gov. Bill Bolling, who serves as the tie-breaking vote in the Senate if the vote falls to party lines (Sen Watkins is a Republican and Senator Saslaw is a Democrat so that does not seem likely), announced that he supports maintaining the moratorium on uranium mining. Let me tell you why I do not want to see the moratorium lifted at this time.

From the Fairfax Water White Paper

Geological exploration has identified more than 55 locations within the Piedmont and Blue Ridge regions of Virginia where uranium is found.  Uranium occurs in the Lovingston rock formation at a fraction of a percent.  In order for a uranium occurrence to be considered a commercially exploitable source of uranium ore, it must be of sufficient size, be at least 0.1% uranium to the other rock components in the deposit and be able to be mined and processed with current technology. So far only the uranium deposits at Cole Hill have been proven to meet these requirements. Even the “rich deposits” at Cole hill will produce 1,000 pounds of waste called tailing for every pound of uranium extracted. The waste, the mine tailings, is the problem.

There are several methods to mine and process uranium. The choice of mining method depends on the quality and quantity of the ore, the shape and depth of the ore deposit, the type of rock, and a wide range of site-specific environmental conditions. Because of the geology in the Commonwealth of Virginia, it is likely that only open pit or underground mining would be viable. While there are risks inherent in mining to worker the uranium miners would also face the additional risk of dust containing radiation.

After the millions of pounds of rock are removed from the ground by conventional mining methods, the uranium must be separated from the rock and minerals and other radioactive materials, impurities removed and yellowcake produced. Yellowcake is a concentrated form of uranium oxide made in a combination of crushing and/or grinding the rock and chemical processes to dissolve the uranium from the rest of the rock using acids or bases to leach the uranium from the rock dust. The yellowcake then needs to be separated, dried, and packaged. There is more than one type of processing and the choice depends on the nature of the uranium ore, the composition of the rock in the formation as well as environmental, safety, and economic factors. During uranium ore processing, several waste products are created, including tailings, leached residue and waste water. Tailings consist of everything that was in the ore except the extracted uranium. Tailings from uranium mining and processing operations contain radioactive materials remaining from the radioactive decay of uranium, such as thorium and radium as well as heavy metals also present in the rock. The real risks to Virginia are the risks of contamination to our water resources from the waste water and tailings. Uranium tailings are a source of radioactive contamination for thousands of years, and therefore must be controlled and stored carefully away from water which will erode and carry the radioactive materials into the ground and surface water.

Over the past few decades, improvements have been made to tailings management systems to isolate tailings from the environment. The long term effectiveness of these management systems has not been tested and uranium mining is typically carried out in arid environments. Virginia is subject to relatively frequent storms that produce intense rainfall. Natural events such as hurricanes, earthquakes, intense rainfall, or drought could lead to the release of contaminants into the waters of Virginia. It is questionable whether modern-engineered tailings containment could be expected to prevent erosion and surface and groundwater contamination for as long as 1,000 years. In Coles Hill alone the tailings waste will amount to over 118,888,000,000 pounds of pulverized rock with radioactive materials that can slowly leach into our groundwater through failure to prevent percolation of precipitation into the tailings containment or through accidents be released from impoundments to surface waters. Though Virginia’s rainfall averages 42 inches a year in past few years alone rainfall has varied from under 30 inches to a high of 82 inches of rain a year. Water is a great solvent and in Virginia it would seem impossible to keep such vast quantities of tailings permanently isolated from water.  

The only use for uranium is for weapons and nuclear powered reactors. The United States currently has 104 nuclear reactors in operation supplying about 20% of U.S. electricity, and in 2011 these reactors required 20,256 short tons of concentrated enriched uranium and this is not expected to change significantly in the future. In 2010, the United States imported 92 % of the uranium that it needed to fuel its nuclear power reactors. There appears to be adequate world supply for our limited number of nuclear power plants at this time. Uranium mining and processing represents unique risks to source water supplies from toxic and radioactive byproducts. The half-life of the uranium 238 and its isotopes is thousands of years. A containment failure will risk the groundwater and surface water supply of the Commonwealth, and for Cole's Hill will endanger the drinking water supply of Virginia Beach if there is a breach in containment. With current technology, the risk is too great.  The uranium will still be there when our knowledge of how to stabilize for hundreds of year the mine tailings increases to the point we can safely mine the uranium without endangering our water resources.

The formation the contains uranium in Virginia from Fairfax Water

What’s EPA Doing about Fracking?

EPA will be holding a webinar on their fracking studies that includes research approach, status, and next steps if you are interested. The webinar will be presented on two different days, Thursday, January 3rd and Friday, January 4th 2013. Jeanne Briskin, Hydraulic Fracturing Research Coordinator, Office of Science Policy, Office of Research and Development will be the instructor and the webinars are: on January 3, 2013, 2:00 PM - 3:00 PM, EST and January 4, 2013, 12:00 PM - 1:00 PM, EST. Just click through on the links and sign up.

The United States has vast reserves of natural gas within shale and rock formations. During the past decade, extracting that gas has become commercially viable as a result of the advances made in horizontal drilling and hydraulic fracturing (fracking) techniques. With the rapid increase in fracking has come the increase in concerns about its potential impacts on drinking water. In response to public concern ignited by the film Gasland and protests by anti-fracking groups, the US House of Representatives requested that the US Environmental Protection Agency (EPA) examine the relationship between fracking and drinking water resources in 2009. In 2011, the EPA began a series of research projects into the impacts and potential impacts of fracking on water. Also, in April 2012 EPA released the first federal air rules for natural gas wells that are hydraulically fractured, specificallyvrequiring operators of new fractured natural gas wells to use “green completion,” which is a series of technologies and practices to capture natural gas and other volatile substance that might otherwise escape the well during the completion period when most volatile release takes place.

Hydraulic fracturing has its own water cycle and involves the pressurized injection of fluids commonly made up of mostly water and chemical additives into a geologic formation. The pressure used exceeds the rock strength and the fluid opens or enlarges fractures in the rock. As the formation is fractured, a “propping agent,” such as sand or ceramic beads, is pumped into the fractures to keep them from closing as the pumping pressure is released. The fracturing fluids (water and chemical additives) are partially recovered and returned to the surface. Natural gas will flow from pores and fractures in the rock into the wells allowing for enhanced access to the methane reserve. Two to five million gallons of water are typically necessary to frack one horizontal well in a shale formation. Water used for fracturing fluids is acquired from surface water or groundwater in the local area. Wastewaters from the hydraulic fracturing process (flowback or water produced in the well) may be disposed in several ways. The water that flows back after fracturing may be returned underground using injection well, discharged to surface waters after treatment to remove contaminants, or applied to land surfaces. Not all fracturing fluids injected into the geologic formation during hydraulic fracturing are recovered. The EPA estimates that the fluids recovered range from 15-80% of the volume injected depending on the site. The long term fate of any residual fluid has not been studied.  

Each stage of the fracking water cycle is a potential area for impact to drinking water supplies especially from human error and irresponsibly and improperly handling chemicals and contaminated water and poorly managing and protecting our water resources.  The steps in the fracking water cycle are:

Water acquisition. Chemical mixing. Pressurized Well injection. Flowback and produced water (collectively referred to as “hydraulic fracturing wastewater”) recovery. Wastewater treatment and disposal. Geology, hydrology and human behavior will produce vastly different outcomes for different regions of the county and different gas companies.

from US EPA

EPA is engaged in a number of research projects that will be the basis of their actions and future regulations for oil and gas operations. Whether the EPA will regulate oil and gas exploration nationally or leave the oversight in the hands of the states is an open question. There is an argument that water resources and geology are very local phenomena and cannot be generalized over the nation and that hydraulic fracturing should remain under local oversight. The 2005 energy law exempts fracking from the Safe Drinking Water Act based on the 2004 EPA study “Evaluation of Impacts to Underground Sources of Drinking Water by Hydraulic Fracturing of Coalbed Methane Reservoirs.” In that report EPA reviewed 11 major coal basins mined for coalbed methane and saw no conclusive evidence that water quality degradation on underground drinking water supplies had occurred as a direct result of the injection of hydraulic fracturing fluids, but fracking of coalbeds generally involves a fraction of the water used in hydraulic fracking of shale gas.

The current fracking projects are a series of studies. Existing Data from multiple sources have been obtained for review and analysis. Well construction and hydraulic fracturing records provided by well drillers are being reviewed for 333 oil and gas wells across the United States; data within these records are being examined to assess the effectiveness of current well construction practices at containing gases and liquids before, during, and after hydraulic fracturing. In addition information on the chemicals and practices used in hydraulic fracturing has been collected from nine companies that hydraulically fractured a total of 24,925 wells between September 2009 and October 2010. Data on causes and volumes of spills of hydraulic fracturing fluids and wastewater are being collected and reviewed from state spill databases.

Computer models are being developed to identify conditions that may lead to impacts on drinking water resources from hydraulic fracturing. The EPA has created hypothetical scenarios for  water acquisition, well injection, and wastewater treatment and waste disposal stages of the water cycle that they hope to have the models evaluate. Computer models are also being used to explore the possibility of subsurface gas and fluid migration from deep shale formations to overlying aquifers in six different scenarios. The effectiveness of the models would be dependent on how closely the model predicts transport behavior in rock and shale and the similarity in behavior of different formations.

Laboratory studies are being performed to identifying potential impacts of inadequately treating hydraulic fracturing wastewater and discharging it to rivers. Experiments are being designed to test how well common wastewater treatment processes remove selected contaminants from hydraulic fracturing wastewater, including radium and other metals. Since wastewater treatment plants are not designed to remove more than biological waste and bacteria, any removal of fracking chemicals and contaminants would be incidental. I do not expect that wastewater treatment plants would be able to treat flowback water for the contaminants associated with geological formations and fracking chemicals.

The EPA has identified chemicals used in hydraulic fracturing fluids from 2005 to 2011 and chemicals found in flowback and produced water. The EPA is performing toxicity assessments based on chemical, physical, and toxicological properties for chemicals with known chemical structures. Existing toxicology models are being used to estimate properties in cases where information is not available. The important thing that EPA is doing is bringing together all the data and previous work to get as complete picture of what we know about how hydraulic fracturing may be impacting our water resources.

Is Our Drinking Water Safe?

The short answer is it depends on where your water comes from, and how it is treated. The drinking water supply can be broken down into three parts: the source water, the drinking water treatment system, and the distribution system which carries the treated water to homes and other buildings. The first steps towards a clean water supply and public health was to disinfect drinking water in the cities (and develop sewer systems). Treating drinking water with either Chloramine or chlorine lowered microbial densities of coliform bacteria, heterotrophic bacteria, Legionella bacteria preventing disease and death. However, these bacteria and the other substances on the primary drinking water list are not the whole story, nor are they the only substances in our water today. Our modern world is filled with chemicals, they exist in pharmaceuticals, household products, personal care products, plastics, pesticides, industrial chemicals, human and animal waste; they are in short, all around us. According to the Toxic Substances Control Act (TSCA) inventory of chemicals there are more than 84,000 chemical substances, as defined in TSCA today (or the last time they updated it). These chemicals include organics, inorganic, polymers, and UVCBs (chemical substances of Unknown or Variable composition, Complex reaction products, and Biological materials).

Public drinking water supplies are still typically treated with either Chloramine or chlorine both are disinfectants. (Disinfection by products are tested for in drinking water supplies.) Chloramine is a combination of chlorine and ammonia that is currently considered best technology for controlling the formation of certain regulated organic disinfection byproducts and has come to replace the use of chlorine in many locations. Since the revisions to the clean water act in the 1990’s chloramine has returned to common use as a distribution system disinfectant after being replaced in 1940’s with chlorine when there were ammonia shortages. Chloramine lowers microbial densities of coliform bacteria, heterotrophic bacteria, Legionella bacteria in the source water and distribution system while minimizing the formation of regulated disinfection by-products.

Under the authority of the Safe Drinking Water Act (SDWA), EPA sets standards for approximately 90 contaminants in drinking water including bacteria from human waste, industrial discharge streams (of great concern back in 1974 when the SDWA was first created) and water disinfection by-products and distribution system contaminants. For each of these contaminants, EPA sets a legal limit, called a maximum contaminant level. EPA requires that all public water supplies be tested for this list of contaminants on a regular basis (from daily, to quarterly, to every other year or longer depending on the contaminant and water system) and meet these minimum standards on average. In addition, EPA sets secondary standards for less hazardous substances based on aesthetic characteristics of taste, smell and appearance, which public water systems and states can choose to adopt or not. Though 90 contaminants is a lot, it is just a small fraction of the chemicals in large scale commercial production in the United States which EPA estimates to be over 7,000 chemicals.

Several of the substance controlled under the SDWA are natural occurring contaminants, 6 are bacteria and 8 are by-products or additives of water treatment; however, the greatest problem is pollution caused by mankind. Anthropogenic pollutants contaminate surface and groundwater as a result of manufacturing, combustion and incinerations air emissions, landfills and spills, stormwater runoff carrying agricultural and surface pollutants and waste water treatment water carrying a wide range of chemical containing substances into surface water and groundwater. The SDWA is a product of its time, in 1974 industrial waste discharge and release was far more common, and the last significant review of the SDWA was 1991. Six of the chemicals regulated under the SDWA have been banned for more than 20 years, but the US Geological Survey (USGS) found traces of at least one banned pesticide in groundwater during the recent study of the quality of the nation’s ground water supply.

The USGS ground water testing found that 10 contaminants were detected at concentrations greater than human-health recommended levels in 1% of the groundwater. Of the ten contaminants, seven were from natural sources and three were man-made. The seven contaminants from natural sources included four geological trace elements (arsenic, manganese, strontium, and boron) and three radionuclides (radon, radium, and gross alpha-particle radioactivity). The three contaminants that exceeded MCLs that were from man-made sources were nitrate (a nutrient), dieldrin (an insecticide that has been banned by the US EPA), and perchloroethene (PCE). Naturally occurring elements, radionuclides and pesticide compounds were extensively found at extremely low concentrations (about 10% of any existing health standard). Trace levels of an herbicide (atrazine or simazine) or an herbicide degradate (deethylatrazine), and the solvents perchlorethene or trichloroethene were widely found in samples from shallow unconfined aquifers without a confining geological layer, though the deeper confined groundwater aquifers remained mostly free of man-made contamination.

In their study of surface water used for drinking water supplies the USGS found a diverse group of contaminants in the source water. The concentrations were low, but the contaminants were ubiquitous. This would indicate a variety of different sources and pathways for these contaminants to reach our drinking water supplies. The concentrations were low, (about 95% of the concentrations were less than one-part per billion); nonetheless, the most commonly detected contaminants in source water were generally detected in finished water at about the same frequency and concentration. Our drinking water treatment systems do not remove these contaminants. The USGS found that as the amount of urban and agri-lands increased within the water shed, the numbers of contaminants in the rivers also increased. Rivers receiving municipal and industrial discharge, as well as discharges from other point and non-point sources from stormwater runoff are impacted by man-made organic contaminants, most of which are unregulated. Only about 40 of the 260 substances the USGS tested for are regulated the rest are unregulated.

The safety of our drinking water system is predicated on the basic assumption of toxicology that “dose makes the poison.” This relationship between exposure and risk has been challenged in the study of endocrine disruptors. Now, there is growing concern for potential endocrine disruptors at extremely low levels. Endocrine disruptors are chemicals that can mimic, block, or otherwise alter animal hormone responses, sometimes affecting their reproduction, development, and behavior, this is actually, how some pest control treatments are designed to work on bugs. A diverse group of chemicals called endocrine disrupting chemicals (EDCs) come from a variety of sources. These chemical have vastly different molecular structures, and become of great concern when they are discovered to be human endocrine disruptors.

The US Fish and Wildlife Service (USFW) and US Geological Survey (USGS) studied the relationship between waste water treatment plants, agricultural chemicals, and the immune-suppressed and inter-sexed fish in the Potomac River (and other locations). Hormones were not detected in the samples, but analysis using yeast screening assays found estrogenic endocrine-disrupting chemicals throughout the sections of the rivers tested, yet their specific source has not yet been identified. The extremely low concentrations of chemicals that was almost undetectable caused significant biological and health impacts among the fish and amphibian populations. Though they cannot identify a single chemical or group of chemicals responsible, the USFW and USGS have embarked on further study to gain greater understanding of the implications of their findings to the earth’s ecosystem.

The structural diversity of potential endocrine disruptors is enormous and it is not known which of these substances might adversely affect living things in subtle ways. Testing for new chemicals is for gross and acute impact, subtle impact is very difficult to identify. The growing class of known endocrine disrupting chemicals can disturb a staggering range of hormonal processes. Like natural hormones, some EDCs bind directly with hormone receptors. The impostors can mimic or block hormone messages with the same, weaker, or stronger responses. Others are more subtle, they interfere with hormone maintenance to prevent or enhance hormones from being made, broken apart, or carried in the bloodstream.

Recycled or reclaimed water is former wastewater (sewage) that has been treated to remove solids, bacteria and certain impurities, and then is used in irrigation, discharged to surface water that is a source of drinking water or injected into the ground to recharge groundwater aquifers. In order to make our river, lake, stream and ocean water safe for fishing and recreation, the Clean Water Act of 1972 mandated elimination of the discharge of untreated waste from municipal and industrial sources. This was the first great success of environmental regulations. Modern waste water treatment plants, usually using sand filtration and chlorination in addition to primary and secondary treatment, were required to meet certain standards. These standards were never designed to render the waste water potable nor to remove the vast number of chemicals and drugs that find their way down our drains today. The design of the combined sewer systems in the largest cities results in regular discharge of raw sewage during storm events. In the United States the cryptosporidium parasite has caused outbreaks of diarrheal disease in the 1990’s and boil water alerts are frequent occurrences in the in the 21st century. We are having difficulties maintaining our most basic water quality let alone protect the population from emerging contaminants. The Environmental Working Group has called for the EPA to do a national assessment of drinking water quality and establish new safety standards, set priorities for pollution prevention projects, and inform the public of the full range of pollutants in their water. In the meantime, while the EPA spends it time addressing carbon dioxide in the atmosphere you need to carefully consider source water quality, and treatment when selecting where to live.