Monday, November 20, 2017

The Wells of Fairfax County 2017

As part of the Virginia Household Water Quality Program Fairfax County Extension held a drinking water clinic for well owners this year. The samples were taken Ocotober 18th 2017 and analyzed for: iron, manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved solids, hardness, sodium, copper, total coliform bacteria and E. Coli bacteria at a cost of $55 to the well owner.
What is tested for are mostly the naturally occurring contaminants and common sources of contamination: a poorly sealed well or a nearby leaking septic system, or indications of plumbing system corrosion. Though this is not an exhaustive list of potential contaminants, these are the most common contaminants that effect drinking water wells. The chart below shows what was found in the 75 samples tested in Fairfax County in 2017.

In order to determine if treatment is necessary, water test results should be compared to a standard. The standard we use is the U.S.EPA Safe Drinking Water Act (SDW) limits. Though private wells do not fall under the regulatory authority of the U.S. Environmental Protection Agency (EPA) or the Safe Drinking Water Act, the SDW act has primary and secondary drinking water standards that we use for comparison. Primary standards are ones that can impact health and from the tested substances include: coliform bacteria, E. coli bacteria, nitrate, lead, and arsenic. Secondary standards impact taste or the perceived quality of the water.

The 2017 Fairfax County water clinic found that over 37% of the wells tested present for coliform bacteria. Coliform bacteria are not a health threat itself, it is used to indicate other bacteria that may be present and identify that a well is not properly sealed from surface bacteria. The federal standard for coliform bacteria is zero, but the federal standard allows that up to 5% of samples can test positive for coliform during a month.

Twoof the homes tested positive for E coli. Fecal coliform and E. coli are bacteria whose presence indicates that the water is contaminated with human or animal wastes. Disease-causing microbes (pathogens) in these wastes can cause diarrhea, cramps, nausea, headaches, or other symptoms. These pathogens may pose a special health risk for infants, young children, and those with compromised immune systems. However, people can drink water contaminated with fecal bacteria and not notice.

If your water is contaminated with coliform but not fecal coliform or E. coli, then you have a nuisance bacteria problem and the source may be infiltration from the surface from rain or snow melt. Typical causes are improperly sealed well cap, failed grouting or surface drainage to the well. Shock chlorinate the well, repack the soil around the well pipe to flow away from the well and replace the well cap. Then after the next big rainstorm retest the well for coliform. If it is still present then a long-term treatment should be implemented: using UV light, ozonation, or chlorine for continuous disinfection. These systems can cost up to $2,000 installed.

If you have fecal coliform in the well or E. coli, your well is being impacted by human or animal waste and you are drinking dilute sewage. If there is not a nearby animal waste composting facility, then you are probably drinking water from a failed septic system- yours or your nearest neighbors. To solve this problem you need to fix or replace the septic system that is causing the contamination, replace the well or install a disinfection and filtration system. Disinfection does not kill Giardia or Cryptosporidium, two microscopic parasites that can be found in groundwater that has been impacted by surface water or sewage. Both parasites produce cysts that cause illness and sometimes death.

Membrane filtration is the usual treatment for these parasites- a one micron membrane is required after disinfection and can be accomplished at home with a reverse osmosis system. The failing septic systems can often be identified by using tracer dyes. While continuous disinfection will work to protect you from fecal bacteria and E. coli, be aware that if your well is being impacted by a septic system, then the well water might also have present traces of all the chemicals and substances that get poured down the drain. Long term treatment for disinfection, and micro-filtration should be implemented: using UV light, ozonation, or chlorine for continuous disinfection, carbon filtration, and anything that is used for drinking should be further treated with a reverse osmosis systems or micro membrane system that works by using pressure to force water through a semi-permeable membrane. Large quantities of wastewater are produced by reverse osmosis systems and need to bypass the septic system or they will overwhelm that system creating more groundwater problems. Reverse osmosis systems produce water very slowly, a pressurized storage tank and special faucet needs to be installed so that water is available to meet the demand for drinking and cooking.

Nitrate can contaminate well water from fertilizer use; leaking from septic tanks, sewage and erosion of natural deposits. None of the wells in our group of 101 samples had nitrate levels above the MCL. The MCL for nitrate is 10 mg/L. Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill from blue-baby syndrome and, if untreated, may die. Symptoms include shortness of breath and a blue ting to the skin common in blue-baby syndrome. The NO3 dissolves and moves easily through soil which varies seasonally and over time as plants use up the nitrate over the summer. Testing in the spring will usually produce the highest levels. Nitrate may indicate contamination from septic tanks, but do not boil the water- boiling water reduces the water and actually INCREASES the concentration of nitrates. Reverse osmosis, or ion exchange is necessary to control the nitrate. None of the wells tested exceeded the MCL.

IThis year we had 9.3% of homes have first draw lead levels above the SDWA maximum contaminant level of 0.015 Mg/L. After the flushing the tap for at least one minute only one home had lead levels above the 0.15 mg/L level; however, many scientists do not believe that any level of lead is safe to drink over an extended period of time. In the homes that had elevated lead in the first draw, it tends to be negatively correlated with pH values and copper pipes. Houses built before 1988 when the ban on lead went into effect and have low pH water typically have higher lead concentrations. Lead leaches into water primarily as a result of corrosion of plumbing and well components, but can also result from flaking of scale from brass fittings and well components unrelated to corrosion and corrosion control techniques such as adjusting pH or alkalinity that are commonly used to neutralize aggressive water will not work in those cases. For most instances, though, a neutralizing filter and lead removing activated carbon filters can be used to remove lead. Recently, some home water treatment companies are offering in home treatment systems that neutralize the water and add orthophosphate other phosphate solution to coat the piping to prevent further corrosion. It should work, but I have never seen such a home system and am not aware of any testing.

Iron and manganese are naturally occurring elements commonly found in groundwater in this part of the country. 8.0% of the wells tested exceed the iron standard and 6.7% exceeded the manganese standard. At naturally occurring levels iron and manganese do not present a health hazard. However, their presence in well water can cause unpleasant taste, staining and accumulation of mineral solids that can clog water treatment equipment and plumbing and discolored water. The standard Secondary Maximum Contaminant Level (SMCL) for iron is 0.3 milligrams per liter (mg/L or ppm) and 0.05 mg/L for manganese. This level of iron and manganese can be detected by taste, smell or appearance. In addition, some types of bacteria react with soluble forms of iron and manganese and form persistent bacterial contamination in a well, water system and any treatment systems. These organisms change the iron and manganese from a soluble form into a less soluble form, thus causing precipitation and accumulation of black or reddish brown gelatinous material (slime). Masses of mucous, iron, and/or manganese can clog plumbing and water treatment equipment.

All systems of removing iron and manganese essentially involve oxidation of the soluble form or killing and removal of the iron bacteria. When the total combined iron and manganese concentration is less than 15 mg/l, an oxidizing filter is the recommended solution. An oxidizing filter supplies oxygen to convert ferrous iron into a solid form which can be filtered out of the water. Higher concentrations of iron and manganese can be treated with an aeration and filtration system. This system is not effective on water with iron/ manganese bacteria, but is very effective on soluble iron and manganese so you need to do further testing to determine what type of iron/manganese you have before you install a treatment system. Water softeners can remove low levels of iron and are widely sold for this purpose because they are very profitable, but are not recommended for just this purpose. Chemical oxidation can be used to remove high levels of dissolved or oxidized iron and manganese as well as treat the presence of iron/manganese (or even sulfur) bacteria. The system consists of a small pump that puts an oxidizing agent into the water before the pressure tank. The water will need about 20 minutes for oxidation to take place so treating before a holding tank or pressure tank is a must. After the solid particles have formed the water is filtered. The best oxidizing agents are chlorine or hydrogen peroxide. If chlorine is used, an activated carbon filter is often used to finish the water and remove the chlorine taste. The holding tank or pressure tank will have to be cleaned regularly to remove any settled particles.

The pH of water is a measure of the acidity or alkalinity. The pH is a logarithmic scale from 0 – 14 with 1 being very acidic and 14 very alkaline. Drinking water should be between 6.5 and 7.5. For reference and to put this into perspective, coffee has a pH of around 5 and salt water has a pH of around 9. Corrosive water, sometimes also called aggressive water is typically water with a low pH. (Alkaline water can also be corrosive.) Low pH water can corrode metal plumbing fixtures causing lead and copper to leach into the water and causing pitting and leaks in the plumbing system. The presence of lead or copper in water is most commonly leaching from the plumbing system rather than the groundwater. Acidic water is easily treated using an acid neutralizing filter. Typically these neutralizing filters use a granular marble, calcium carbonate or lime. If the water is very acidic a mixing tank using soda ash, sodium carbonate or sodium hydroxide can be used. The acid neutralizing filters will increase the hardness of the water because of the addition of calcium carbonate. The sodium based systems will increase the salt content in the water. Eight percent of the wells tested were found to have acidic water this year.

Water that contains high levels of dissolved minerals is commonly referred to as hard. Groundwater very slowly wears away at the rocks and minerals picking up small amounts of calcium and magnesium ions. Water containing approximately 125 mg/L can begin to have a noticeable impact and is considered hard. Concentrations above 180 mg/L are considered very hard. As the mineral level climbs, bath soap combines with the minerals and forms a pasty scum that accumulates on bathtubs and sinks. You either must use more soap and detergent in washing or use specially formulated hard water soap solutions. Hard water can be just a minor annoyance with spotting and the buildup of lime scale, but once water reaches the very hard level 180 mg/L or 10.5 grains per gallon, it can become problematic. One a well tested at 254.2 mg/L, but overall only 9.3% of homes tested had hard water. Given the number of homes with elevated sodium and our local geology, it is probably a reflection of the number of homes with water softeners.

Water softening systems are used to address the problem are basically an ion exchange system. The water softening system consists of a mineral tank and a brine tank. The water supply pipe is connected to the mineral tank so that water coming into the house must pass through the tank before it can be used. The mineral tank holds small beads of resin that have a negative electrical charge. The calcium and magnesium ions are positively charged and are attracted to the negatively charged beads. This attraction makes the minerals stick to the beads as the hard water passes through the mineral tank. Sodium is often used to charge the resin beads. Water softeners can be used to remove small amounts of other metals like iron and some forms of arsenic. As the water is softened, the sodium ions are replaced and small quantities of sodium are released into the softened water, thus the salty taste of softened water. When the water softening system is recharged the excess sodium solution carrying the calcium and magnesium is flushed to the septic system which may shorten the life of the drain field.

At the present time the EPA guidance level for sodium in drinking water is 20 mg/L. This level was developed for those restricted to a total sodium intake of 500 mg/day and does not necessarily represent a necessary level for the rest of the population. Based on taste of the water levels of sodium should be below 30 to 60 mg/L based on individual taste. Water softeners ten to cost around $4,500 installed. They are often sold to solve every water quality problem because they have some ability to remove other contaminants. The resin bed used will determine specific contaminant removal. Softened water can have a low pH and high levels of chloride, corrosion control problems and softening systems can encourage the growth of reducing bacteria. Water softening systems add sodium. Reverse osmosis systems and distillation systems remove sodium and are safe for household use, but addressing hard water by using vinegar to descale pots and dishwashers, regularly draining hot water heaters, and using detergents formulated for hard water might be a better solution for you if your water like mine is only modestly hard.

No wells were found that had arsenic exceeding the EPA MCL for drinking water of 10 ppm. While arsenic is a naturally occurring element found in soil and groundwater it is not typically found at significantly elevated levels in this geology. Arsenic can also be an indication of industrial or pesticide contamination. Arsenic can be very tricky to remove depending on its form and the other contaminants present. Possible solutions for elevated levels of naturally occurring arsenic are reverse osmosis system or iron oxide filter system.

Thursday, November 16, 2017

New Study finds no Cancer Link to Glyphosate

A new study published last week in the Journal of the National Cancer Institute found no association between cancer and exposure to glyphosate, the active ingredient in the herbicide “Roupndup” and the most commonly used herbicide worldwide. In 2015, the International Agency for Research on Cancer classified glyphosate as “probably carcinogenic to humans,” noting strong mechanistic evidence and positive associations for non-Hodgkin lymphoma (NHL) in some epidemiologic studies; though previous evaluations had found no statistically significant associations with glyphosate use and any cancer,

This new study is part of the Agricultural Health Study which has been tracking the health of thousands of agricultural workers and pesticide applicators and their families in Iowa and North Carolina for over 20 years. The study was led by Laura Beane Freeman of the National Cancer Institute. The Agricultural Health Study has tracked and studied 54,251 pesticide applicators, 44,932 or 82.9% who had used glyphosate since the 1990’s.

The scientists studied of glyphosate use and cancer occurrence in this large group of pesticide applicators, and observed no associations between glyphosate use and overall cancer risk or with total lymphohematopoietic cancers, including NHL and multiple myeloma. However, the scientist found some evidence of an increased risk of acute myeloid leukemia (AML) for applicators, particularly in the highest category of glyphosate exposure compared with those who never used glyphosate. The fact that no other studies have reported an association between glyphosate and AML risk calls for cautious interpretation of the results. However, the observed pattern of increasing risk with increasing exposure and the lagged exposure of 10 or more years raises concern and the need for additional long term studies.

Today, Americans spray an estimated 180-185 million pounds of the weed killer, on their yards and farms every year. All the acute toxicity tests have indicated glyphosate is nearly nontoxic to mammals, but concern has been raised about long term exposure. The current findings are reassuring, but given the prevalence of use of this herbicide not only in the United States but worldwide, efforts should be undertaken to replicate these findings as soon as possible.

Monday, November 13, 2017

Arsenic in Your Well Water

A new study from the U.S. Geological Survey and Centers for Disease Control and Prevention was released last month. The author estimates that about 2.1 million people in the U.S. may be getting their drinking water from private domestic wells considered to have high concentrations of naturally occurring arsenic, presumed to be coming primarily from rocks and minerals through which the water flows.

About 44 million people in the lower 48 states use water from domestic wells,” said Joe Ayotte, a USGS hydrologist and lead author of the study. Private wells are the dominant source of drinking water for people living in rural parts of the United States. In most of the U.S., domestic well water quality is not regulated; it is up to the well owner to understand the arsenic hazard and other water quality hazards and take steps to test their water and treat it if necessary. This study is a good reminder that prudent, routine testing of the water is an essential first step for these homeowners and their families.

Using water samples from more than 20,000 domestic wells, the researchers developed a statistical model that estimates the probability of having high arsenic in domestic wells in a specific area. The researcher used a standard of 10 micrograms of arsenic per liter -- the maximum contaminant level allowed for public water supplies and used it developed maps of the contiguous U.S. showing locations where there are likely higher levels of arsenic in groundwater, and how many people may be using it. They used that model in combination with information on the U.S. domestic well population to estimate the population in each county of the continental United States with potentially high concentrations of arsenic in domestic wells.

Much of the country is potentially impacted by arsenic and is a national public health concern. Some of the locations where the authors estimated the most people have high-levels of arsenic in private domestic well water include:
  • Much of the West – Washington, Oregon, Nevada, California, Arizona, New Mexico
  • Parts of the Northeast and Midwest – Maine, Massachusetts, New Hampshire, New Jersey, Maryland, Michigan, Wisconsin, Illinois Ohio, Indiana
  • Some of the Atlantic southeast coastal states – Florida, Virginia, North Carolina, South Carolina
Long-term exposure to arsenic in domestic wells may cause health-related problems, including an increased risk of cancer. Recent work in the U.S. also indicates that low-level arsenic may impact fetal growth and may be related to preterm birth. Public water supplies are regulated by the U.S. EPA, but maintenance, testing and treatment of private water supplies are the sole responsibility of the homeowner. Though about 44 million people in the U.S. get their drinking water from private wells, surveys indicate many homeowners are unaware of some basic testing that should be done to help ensure safe drinking water in the home.

Like may other contaminants, high concentrations of arsenic in water do not effect taste or smell, the only way to know how much arsenic is in drinking water is to have it tested. Testing you well is the first step in ensuring the safety of your drinking water supply. After testing it may be necessary to treat the water to reduce or eliminating the health risks or concerns.

You may wish to consider water treatment methods such as reverse osmosis, ultra-filtration, distillation, or as a last choice ion exchange. Typically these methods are used to treat water at only one faucet. Though anionic exchange systems (water softeners) are whole house systems, they may not be the best choice. These systems use a physical/chemical process to exchange ions between a resin bed and water passing through. These systems can remove calcium carbonate, iron and manganese, and lower nitrate and arsenic levels. Specific contaminant removal is determined by the composition of the resin bed used. Other constituents in water can compete with arsenic for the resin sites reducing the systems effectiveness. Also, depending on your water chemistry, they may create other problems.

To understand the risk and to make progress on reducing exposure in a systematic way, we need better understanding of groundwater chemistry and estimates of the population affected by high arsenic concentrations and other contaminants. The work by the USGS and the Virginia Household Quality Program accumulates data and helps homeowners identify these risks.

Thursday, November 9, 2017

Neonicotinoids in Honey

In a recent study published in Science, Mitchell et al found that most honey sampled from around the world between 2012 and 2016 contained neonicotinoid pesticides at levels known to be neuroactive to bees. Neonicotinoid are currently the most widely used class of pesticides worldwide. The neonicotinoids are taken up by plants and contaminate the pollen and nectar. Neonicotinoids have been identified or suspected as a key factor responsible for the decline in bees.

During the winter of 2006-2007, a large number of bee colonies died out, losses at the impacted beekeeping operations were reported to be from 30% to 90%. While many of the colonies lost during this time period exhibited the symptoms from parasitic mites, many were lost, from unknown cause. The next winter, the number of impacted honey bee operations spread across the country. The phenomenon was termed Colony Collapse Disorder.

Over the past decade Colony Collapse Disorder has spread around the world. In 2012, 31% of the U.S. honey bee colonies were wiped out. The year before that it was reported as 21% of colonies lost. These losses if they continue could have a catastrophic impact on agriculture. One third of all food eaten in the United States requires honey bee pollination.

Recent field studies published this year in Science have found widespread contamination of agricultural land worldwide by neonicotinoid pesticides. These findings suggest that chronic low level exposure to neonicotinoids may be impacting bee colonies. Currently pesticide safety testing focuses on acute exposure risk not extremely low levels of chronic exposure. Neonicotinoids work by targeting the nicotinic acetylcholine receptors in the insect brain which are responsible for learning and memory. Acute activation of theses receptors by neonicotinoids causes seizure then neuron non-response.

During experiments carried out by Piroinen et al in 2016 it was found that low level neonicotinoid exposure causes neural dysfunction that limits a bee’s capacity to learn and remember. Chronic exposure resulted in reduced foraging ability (Gill et al 2012) and poor colony growth (Moffat et al 2015, 2016) and is believed to be a factor in Colony Collapse Disorder.

The vast majority of plants are pollinated by insects, and bees are responsible for the vast majority of pollination. Commercial agriculture uses honey bees raised to pollinate its crops. A Cornell University study estimates that the value of honey bee pollination in the United States is more than $14.6 billion annually.

In the current study, Dr. Mitchell found neonicotinoids in 75% of 198 honey samples collected from honey producers. In North America 86% of the samples had neonicotinoids detected. The concentrations found in honey are below the maximum residue level allowed for human consumption, but within the bioactive range for honey bees.

Although recording of pesticide use is required in the European Union and the United States (under the 1990 Farm Bill), it is not collected into a searchable database that would allow the finding of statistical correlation of pesticides used with human chronic diseases or ecosystem damage. Chronic low level exposure may be more damaging than we ever imagined. It is time to reexamine our assumptions and develop methods to measure impact from chronic low level exposure.

Monday, November 6, 2017

Environment Impacts from the Kline Farm Development

Stanley Martin Homes wants to develop farm land owned by the Kline family at the intersection of Prince William Parkway and Libera Avenue. The Prince William County Planning Commission will hold a public hearing on a series of permit requests and zoning changes associated with this development on November 15th 2017 at 7 pm in the Board Chambers of the McCoart Administration Building, 1 County Complex Court, Prince William, VA 22192. If you have an opinion on whether the comprehensive plan and zoning should be amended as described below you should attend and make your voice heard or call you supervisor’s office.

Stanley Martin Homes wants a Comprehensive Plan Amendment (CPA) to change the long-range land use designation for the over 100. acres from CEC, Community Employment Center, and SRR, Semi-Rural Residential, to CEC with a Center of Community Overlay and with an expanded study area. These changes would allow Stanley Martin build 329 townhomes, 63 single-family homes and 400,000 square feet of commercial space and an elementary school. The properties in the development will be connected to public water from supplied by Prince William Public Service Authority and with surface water as the source supply. So, there will be no increase in the use of groundwater in the immediate area.

The Kline Farm property encompasses a bit more than 100 acres and is generally located south and southeast of the intersection of Prince William Parkway and Liberia Avenue, and north of Buckhall Road. The property is located in a transitional area of the county that is adjacent to the City of Manassas. North of the site and across the Prince William Parkway is the Prince William Commerce Center, still under development and will contain mixed retail/commercial/office uses, as well as the suburban residential neighborhood of Arrowood and the semi-rural residential neighborhood of Hyson Knolls to the northeast. East and southeast of the site is semi-rural residential communities and A-1 zoned property. To the west and northwest is the City of Manassas with existing retail service/commercial strip development. Southwest of the subject site is existing suburban residential development.

There are important environment concerns that need to be considered. Residents within the abutting Hynson Knolls community, homeowners bordering Buckhall Road and homes along Lake Jackson Drive rely on private wells for water and septic systems for wastewater disposal. In a “Preliminary Hydrogeological Assessment-Klein Site” prepared by SES/TrueNorth they do a preliminary look at whether the development of the site is likely to have an adverse impact on surrounding private wells and septic systems. The properties in the development will be connected to public water from supplied by Prince William Public Service Authority and with surface water as the source supply. So, there will be no increase in the use of groundwater in the immediate area.

The consultants only reviewed the existing well construction records dating back about 40 years when Hynson Knolls was first developed; existing published hydrology and geology work by the U.S. Geological Survey dating to 1990 and earlier; development of a theoretical groundwater budget and a fracture trace analysis of a 1978 photograph to determining the general flow of groundwater. No physical testing of the aquifer was performed and no recent data records were used.

Private wells draw their water from groundwater. Geology, climate, weather, land use and many other factors determine the quality and quantity of the groundwater available. Within Prince William County Virginia there are four distinct geologic provinces: (1) the Blue Ridge, (2) the Culpeper Basin, (3) the Piedmont, and (4) the Coastal Plain. The U.S. Geological Survey divides the four geologic provinces of the county into seven hydrogeologic groups based on the presence and movement of the ground water calling them groups: A, B, B1, C, D, E and F. About 27 years ago the U.S. Geological Survey studied the groundwater systems within Prince William County. You can review that report if you wish to see the entirety it is by Nelms and Brokman.

The consultants for Stanley Martin Homes identify the site as located within Hydrogeological Group E. The Klein Farm and vicinity are within a fractured bedrock aquifer in which groundwater availability and flow are controlled by fractures and joints within the rock. Hydrogeologic group E consists of metasedimentary, meta-volcanic, and other metamorphic rocks. Rocks within hydrogeologic group E tend to have poor to moderate water-bearing potential, and thin- to thick cover of overburden. Ground-water storage tends to be predominantly in the overburden which is typically relatively granular and porous. This is a water table aquifer separate from but hydraulically connected to the underlying bedrock aquifer. According to that USGS report by Nelms and Brockman, some of the poorest yielding wells are located in hydrogeologic group E.

The fracture trace analysis performed by Stanley Martin Homes consultant found a predominant west-northwest to east-southeast regional fracture orientation; however, there was a notable but less prominent southwest to northeast regional fracture orientation also present. The groundwater flow in Prince William county is generally to the east-southeast, but there is considerable variation and surprises in the flow as documented by monitoring at several cleanup sites in the county and suggested by the fracture analysis.

In developing the theoretical groundwater budget the Stanley Martin Homes consultant assumed that the groundwater recharge rate for the site was equivalent to the average groundwater recharge for Prince William County. This is unlikely to be true. Not only does the geology vary across the county with different water bearing and storage potential in the different hydrogeologic groups, but Prince William county is over 52% open space, including the Prince William Forest Park, the Manassas Battlefield Park, Quantico, and the Rural Crescent.

It appears that the USGS studies that determined an “average recharge” was based on took place at Cedar Run and Broad Run, not characteristic of the hydrogeologic group underlying Klein property and adjacent area. It is unlikely that this site in its current state recharges at the “average recharge rate for the County” and the actual recharge rate of groundwater underlying adjacent to this site needs to be determined.

Flux estimates of components of the hydrologic cycle can be made by creating a water budget in which the various components must balance. Such a water balance approach can be reasonably accurate when all of the terms in the budget can be calculated or reasonable estimated. This approach is appropriate for the scale of the entire Commonwealth, but not on a smaller scale like the Kline property and adjoining neighborhood. On a small local scale these estimates are not at all accurate or appropriate methods of determining groundwater adequacy or impact. Most accurate methods used to estimate recharge are highly dependent on local measurements in both space and time (Healy and Scanlon, 2010) this would need to be done for the Kline property and the surrounding neighborhoods to provide a high level of certainty that the availability, quality and sustainability of groundwater supplying the adjacent neighborhood wells would not be impacted .

This information is necessary to ensure that the neighbor’s water supply will not be impacted over time by the development. If the county comprehensive plan and zoning amendments go through it is essential that the neighbors be assured that their groundwater supply will be adequate to serve their wells into the future and not be depleted slowly over time.

Stanley Martin Homes has proffered to engage an environmental professional to perform a well yield and limited water quality test on any lawfully operating household water supply well for residential property located within 800 feet from the Kline property line to establish a baseline for the closest wells. Those well owners may request a re-evaluation of their well if a negative impact is suspected. If the impact is confirmed by the reevaluation then there is a procedure for the homeowner to request one of three forms of resolution within 30 days; repairing the well, drilling a new well or connecting the home to the public water system.

Sounds good; however, 800 feet which is effectively the first line of homes may not include enough area to ensure no impact. The U.S. EPA standard for determining impact is a much greater radius typically including 2.0 miles for class II a groundwater under the EPA’s Groundwater Protection Strategy. The scope to testing should be defined and include all primary and secondary contaminants regulated under the Safe Drinking Water Act. Finally, 30 days is too short to determine if a well can be repaired, identify and permit a new well site with the County Public Health Department , or determine if the home can be or should be connected to the public water supply. In addition, depletion of groundwater can be a very slow but real process and it might take years for homeowners to notice impact to their wells.

There are other concerns. There is a gas station planned for the development within 600 feet of a private drinking water well. To prevent fuel contamination of the aquifer the Sheets gas station planned for the Kline property development should have secondary containment, constant monitoring, double walled piping, tank and dispenser sumps to prevent leaks and spills and contain on the property any releases. If any of the other commercial sites or the school site will have underground fuel tanks they should be similarly equipped.

The Prince William County Watershed Management Branch found that the proposed amendment to the comprehensive plan and rezoning would negatively impact the protection of environment resources. They stated that retaining the SRR long range land use “will achieve notably greater preservation of existing land features, less impervious area and greater protection of environmental resources.” Mitigation of this impact needs to be included in the proposal for the site.

Finally, the U.S. Environmental Protection Agency, EPA, mandated a contamination limit called the TMDL (total maximum daily load for nutrient contamination and sediment) to restore the Chesapeake Bay and its watershed. About half of the 39,490 square mile land area of Virginia is drained by the creeks, streams and rivers that comprise the Chesapeake Bay watershed, including all of Prince William County.

This TMDL limits discharge of nitrogen, phosphorus and sediment from waste water treatment plants, agricultural operations, urban and suburban runoff, wastewater facilities, septic systems, air pollution and other sources in the county. To achieve this goal Virginia developed a remediation plan acceptable to the EPA called a Watershed Implementation Plan (WIP). We have reached the halfway point in the program and the EPA will evaluate the plan, goals and require a revision to meet the mandated targets. At the last evaluation point Virginia (including Prince William County) was notified that “EPA will maintain enhanced oversight for Virginia urban/suburban stormwater and will continue to monitor Virginia’s progress in closing the nutrients and sediment gap in the 2016-2017 milestone period.”

The increased nitrogen, phosphorus and sediment that will result from the change in use of the Kline property needs to calculated and accounted for. The impact of the Kline property development on the TMDL needs to be mitigated in another way if the Comprehensive plan and zoning are amended.

Thursday, November 2, 2017

Emergency Disinfection of Your Well after the Flooding

Severe flooding can cause septic waste and even chemicals from cars and factories can enter groundwater making it unsafe to drink for days or even months depending on the extent of contamination and flow rate of groundwater. Essentially, the water will have to clear itself through natural attenuation (filtering by the soil and the contamination moving with the flow of the groundwater). A well may not be a safe source of water after the flood, but in all likelihood it will recover. Often all you need to do is flush the well then disinfect it.
Be aware that waste water from malfunctioning septic tanks or chemicals seeping into the ground can contaminate the groundwater for several weeks if there was significant flooding.  The first thing you need to do is respond to any immediate problems and then test the water periodically to verify the continued safety of drinking water.

Unless your well was submerged near a trucking depot, gas station or other industrial or commercial source of chemicals it is likely that torrential rains or flood waters have infiltrated your well and you have “dirty or brownish” water from surface infiltration. This is especially true if you do not have a sanitary cap on your well or have a well pit. Historically, it was common practice to construct a large diameter pit around a small diameter well. The pit was intended to provide convenient access to underground water line connections below the frost line. Unfortunately, wells pits tend to be unsanitary because they literally invite drainage into the well creating a contamination hazard to the water well system. It is most likely if your yard was flooded or your well submerged that you have some surface infiltration of water. In that case, chlorine shocking your well should disinfect your well and last at least 7-10 days.

If your water is brown, the first thing you should do is run your hoses (away from your septic system and down slope from your well) to clear the well. Run it for an hour or so and see if it runs clear. If not let it rest for 8-12 hours and run the hoses again. Several cycles should clear the well. What we are doing is pumping out any infiltration in the well area and letting the groundwater carry any contamination away from your well. In all likelihood the well will clear of obvious discoloration. Then it is time to disinfect your well. This is an emergency procedure that will kill any bacteria for 7 to 10 days.
After 10 days you need to test your well for bacteria to make sure that it is safe. Testing the well for bacteria would determine if the water were safe to drink. A bacteria test checks for the presence of total coliform bacteria and fecal coliform bacteria. These bacteria are not normally present in deeper groundwater sources. They are associated with warm-blooded animals, so they are normally found in surface water and in shallow groundwater (less than 20-40 feet deep). Most bacteria (with the exception of fecal and e-coli) are not harmful to humans, but are used as indicators of the safety of the water.

To disinfect a well you will need common unscented household bleach.  For a typical 6 inch diameter well you need 2 cups of regular laundry bleach for each 100 foot of well depth to achieve about 200 parts per million chlorine concentration. You will also need rubber gloves, old clothes and protective glasses to protect you from the inevitable splashes, and don't forget a bucket to mix  bleach with water to wash the well cap.
  •        Put on the old clothes and safety glasses
  •        Run your hoses from the house to the well
  •        Fill bucket with half water and half chlorine. 
  •        Turn off power to the well
  •        Drain the hot water tank
  •        Remove well cap
  •        Clean well cap with chlorine and water solution and place in clean plastic bag
  •        Clean well casing top and well cap base using brush dipped in chlorine water
  •        Pull wires in the well aside if they are blocking the top of the well and clean them with a rag dipped in chlorine water mixture. Make sure there are no nicks or cuts in the wires. 
  •        Put the funnel in the well top and pour in the chlorine and water mixture
  •        Now pour in the rest of the chlorine SLOWLY to minimize splashing
  •       Go back to the basement and turn the power to the well back on
  •        Turn on the hose and put it in the well 
  •        Sit down and wait for about 45 minutes or an hour
  •        After 45 minutes test the well to make sure that the chlorine is well mixed
  •        Use the hose to wash down the inside of the well casing
  •        Turn off the hose
  •        Carefully bolt the well cap back in place
  •        Now go back into the house
  •        Fill your hot water heater with water
  •        Draw water to every faucet in the house until it tests positive for chlorine then flush all your toilets. Turn off your ice maker. 
  •        Then do not use the water for 12-24 hours 
  •        Set up your hoses to run to a gravel area or non-sensitive drainage area. The chlorine will damage plants 

After 16 hours turn on the hoses leave them to run for the next 6-12 hours. The time is dependent on the depth of the well and the recharge rate. Deeper wells with a faster recharge rate take longer. If you cannot run your well dry and it recharges faster than the hoses use water you will need to keep diluting the chlorine. If you can run your well dry, you might have to let it recharge and run the water off again to clear the chlorine.

       After about 6 hours of running the hoses begin testing the water coming out of the hose for chlorine. Keep running the hose and testing the chlorine until the chlorine tests below about 1 ppm.
  •        Drain the hot water heater again, open the valve to refill it and turn it back on
  •        Open each faucet in the house (one at a time) and let run it until the water tested free of chlorine. Be aware the hot water will sputter- big time- until all the air is out of the system. Flush all the toilets
  •        Change the refrigerator filter cartridge and dump all your ice and turn your ice maker back on. 

It is important not to drink, cook, bath or wash with this water during the time period it contains high amounts of chlorine whose by products are a carcinogen. Run the water until there is no longer a chlorine odor. Turn the water off. The system should now be disinfected, and you can now use the water for 7 to 10 days when the effects of the disinfection wear off. Hopefully, a single disinfection will be enough. 

Unlike public water systems, private systems are entirely unregulated; consequently, the well testing, and treatment are the voluntary responsibility of the homeowner. Virginia Master Well Owner Network (VAMWON). volunteers can help simplify understanding the components of a well and private drinking water system. The VAMWON volunteers and agents can provide information and resource links for private well owners and inform Virginians dependent on private water systems about water testing, water treatment, and system maintenance. You can find help in Virginia  or my contact information through this link by entering Prince William County or my name in the search box. I am happy to answer emails.

Monday, October 30, 2017

Farming in America

The “Farm Bill” is coming up for renewal. For the uninformed and that is most of us, the Agricultural Act of 2014 (2014 Farm Bill) is made up of 12 titles governing a wide range of food- and agriculture-related policy areas and impacts the food we eat, hunger in America, and the health of our lands and waterways. The Congressional Budget Office said that the total cost of the last Farm Bill would be $489 billion over its 5 year life (2014-2018). That is almost $98 billion a year.

from USDA
 Nutrition programs, the Supplemental Nutrition Assistance Program, or SNAP – which provides direct assistance to households classified as food insecure account for more than 80% of this total, with outlays for crop insurance, conservation, and food commodities representing the other 20%. For some reason, all the political noise and debate is focused on the less than $20 billion in subsidies the farm bill provides to farmers and ranchers.

That is because the Farm Bill matters. The Farm Bill impacts everything about our food system: what crops get subsidized, how much foods cost, how land is used. Though the bulk of the dollars ensures low-income Americans have enough to eat, the Farm Bill determines what is available for all of us to eat. Yet few of us understand what is in the bill and how it works. Though I deal with conservation programs, I am among the many.

According to Marion Nestle a former Professor, of Nutrition, Food Studies, and Public Health, at New York University, from which she recently retired, 80% of farm subsidies go to corn, grains and soy oil, dairy gets 3%, livestock: 2%, fruits and vegetables: get less than 1%, tobacco 2%, and cotton: 13%. Dr. Nestle is the author of Food Politics: How the Food Industry Influences Nutrition and Health and Safe Food: The Politics of Food Safety as well as 6 other really worthwhile books. The little know farm bill has been at the center of American politics for several generations.

The American political system is divided by urban and rural regionalism. Many of the world views that separate us have more to do with whether we live in urban or rural areas than anything else. This has been true since the 1960’s, but it seems much more stark now and our divisions are greater than ever before. The joining of SNAP (food stamps) and agricultural subsidies and programs ensures that Congress can muster enough votes to pass both farm supports and SNAP which might not pass as bills on their own. A bit of politics in the 1960’s has successfully brought us all together to hate and support the the farm bill.

The Farm Bill and its implications are a mess. The Department of Agriculture farm crop insurance, conservation, research and outreach essential to our food system and the survival of family farms; and the assistance to households classified as food insecure are both essential. According to a 2015 White House fact sheet, SNAP helps about 46 million low-income Americans put food on the table. Eliminating hunger in the United States is a moral imperative for our nation.

We were once a nation of farmers, today there are about 2,062,000 farms in the United States. Of these farms 89.7% are classified as small family farms, 6.1% are midsize family farms, 2.9% are large family farms and only  1.3% are non-family farms. Ninety percent of farms are small, and these farms accounted for 48% of the land operated by farms in 2015, but account for only 24% of food production. Large million-dollar farms accounted for half of farm production in 2015, up from a third in 1991.

Nevertheless, small family farms accounted for 57% of poultry and 52% of hay production. Family farms of various types together accounted for 98.7% of farms and 89% of production in 2015. Since 1991, agricultural production has shifted to million-dollar farms both family and non-family farms.

Despite the image carried by most people, farm households in general are not low income when compared with all U.S. households and U.S. households with a self-employed head. Median household income for farmers is higher for each size of farm category than median income for all U.S. households in 2015 ($51,700).
from USDA

Thursday, October 26, 2017

Nearby Development can Impact Wells

Traditional development practices cover large areas of the ground with impervious surfaces such as roads, driveways, sidewalks and buildings. This is especially true for higher density and mixed use developments. This kind of development impacts the groundwater beneath the development and in the surrounding area. These paved and impervious surfaces prevent rainwater from infiltrating into the ground, causing it to run off site at velocities and volumes that are much higher than would naturally occur. According to data from the U.S. EPA, when development disturbs more than 10% of the natural land by covering surfaces with roads, driveways, walkways, patios, and homes the natural hydrology of the land is disturbed, irreparably disturbed. It may take months or even years before the impact to the aquifer becomes obvious as water resources are depleted. Rainfall cannot soak through these hard surfaces and recharge the groundwater; instead the rain water flows across the pavement picking up pollutants along the way. The storm water flows into ditches or storm drains, which typically dump the water, pollutants and debris carried in the stormwater into our streams and waterways and increasing the pollutants in the steams and rivers.

Groundwater is water beneath the surface of the earth. It is one of our nation's most important natural resources and is often taken for granted. According to the U.S. Geological Survey (USGS) 24.7% of the domestic water supply in Virginia comes from groundwater- 195 million gallons a day. Groundwater is the sole source of drinking water for the population who are not connected to city or community water systems.

The water level in the aquifer that supplies a well does not always stay the same. Droughts, seasonal variations in rainfall, and pumping affect the level of the water table. If a well is pumped at a faster rate than the aquifer around it is recharged by precipitation or other underground flow, then water levels in the well can fall. This is what happens during times of drought and in depleted aquifers in the summer when there is little or no rain.

But there are other forces that can impact the recharge of a well. Land use changes that significantly increase impervious cover and stormwater velocity can prevent water from soaking into the earth and reduce recharge of the groundwater making existing wells more susceptible to drought and overtime reducing the amount of groundwater. Significant increases in groundwater use for irrigation of crops or playing fields, or commercial purposes can overtax and aquifer and dry out neighboring wells. Unless there is an earthquake or other geological event groundwater changes are not abrupt and problems with water supply tend to happen slowly as demand increases with construction and recharge is impacted by adding paved roads, driveways, houses and other impervious surfaces.

The water level in a groundwater wells naturally fluctuates during the year and this tends to mask a slowly decreasing aquifer or falling groundwater level. Groundwater levels tend to be highest in the early spring after winter snowmelt and spring rainfall when the groundwater is recharged. Groundwater levels begin to fall in May and typically continue to decline during summer as plants and trees use the available shallow groundwater to grow and streamflow draws water. Natural groundwater levels usually reach their lowest point in late September or October when fall rains begin to recharge the groundwater again so it is hard to see a slow and gradual loss of an aquifer even if you monitor the groundwater level. However, unless the groundwater level falls below the pump level it is typically unnoticed. It is essential for the long term sustainability of our communities that the long term impact to the aquifer be assessed before the surrounding land use is changed or developments are approved.

Monday, October 23, 2017

Massive Sewer Clog in Baltimore Removed

A dry-weather sewer overflow happened in Baltimore on September 21st . Nearly 1.2 million gallons of raw sewage flowed into Jones Falls. The cause of this overflow was a massive plug of grease, “flushable” wipes, disposable diapers and other things flushed down the toilets in the city. The Department of Public Works in Baltimore called the 20 foot clog a “fatberg” after the 130 ton clog of fat that was found clogging the London sewer system earlier in September. Last week the  Baltimore Department of Public Works managed to remove fatberg sucking it out of the sewer using their pipe cleaning equipment. The cost of removal was estimated to be $60,000.

Overflows of the sanitary sewer in that area of Baltimore had become more and more common following heavy rains. Engineers for the Baltimore City Department of Public Works (DPW) decided to explore the sewer in that area to determine the cause of the recent dry-weather overflows. They sent a machine with a closed-circuit television camera into the sewer, and soon discovered the walls of the sewer pipe were caked with congealed fats, oils, and grease or FOG as its called in the waste industry.

The buildup of FOG inside the pipe was so thick that it slowed sewer water moving through that area. Engineers estimate that 85% of the pipe, which is 24 inches across and more than 100 years old, was blocked. This resulted in sanitary sewer overflows into the stormwater system to prevent backed up sewage from surfacing on the streets.

Instead, the overflow is diverted into the stormwater system and onto the Jones Falls. The city hopes to eliminate a handful of points that divert sewage to the stormwater system when an expansion of the Back River Wastewater Treatment Plant is completed in late 2020. This work is being done under the City’s sewer system consent decree.

FOG comes primarily from food such as cooking oil, lard, shortening, meat fats, sauces, gravy, mayonnaise, butter, ice cream and soups. Sinks, dishwashers, cleaning wastewaters and food scraps put down disposals deliver the FOG to the sewer system, it can be liquid or solid when you put it down the drain, but turns viscous or solid as it cools in the miles of underground sewer pipes. As the FOG builds up with other debris flushed down the toilets, it restricts the flow in the pipe and can cause sewage to back up into homes and businesses, premature failure of the sewer pipes, increased incidence of sinkholes, or in combined systems like Baltimore, Alexandria and Washington DC sewage released to the stormwater system.

FOG only really creates problems for the sewer lines if there is a disruption, like a tree root in a joint, or sag under a highway, a pumping station or something that might give the FOG a chance to catch on the pipe surface and cling to the walls of the sewer system. Since all pipes have some friction points, FOG is always a problem. The FOG builds up one layer at a time making a smaller, narrower path for the water and waste to travel through, ultimately causing a backup or pipe to burst. Time creates wear and tear on a pipe and without aggressive maintenance and with the addition of wipes and other debris the problem grows to unbelievable proportions.

Restaurants and commercial kitchens are required to have grease traps between the sink and floor drains and the sewer connection and capture and recycle their grease, by having it hauled away. Private residences are not subject to the same regulations as food service establishments but should still take steps to keep fats, oils and grease and non-flushable items out of the sewer system. If you want to see what fatberg looked like see the video.  Here are a few simple tips to remember whether you are on public sewer or have a septic system:
  • Do not put FOG down the drain.
  • During food preparation and cleanup, pour unused grease from the “pan to the can.” Once it solidifies in an empty can, put it in the trash.
  • Do not flush “flushable” wipes; put them in the trash instead. Wet wipes don’t break down in water and create sewer blockages.
  • The only items that should be considered flushable are poo, pee, and toilet paper.

Thursday, October 19, 2017

U.S. Water Use

from USGS
According to the U.S. Geological Survey (USGS) report “Estimated Use of Water in the United States in 2010,” which is the latest data available from the USGS, The United States uses 355 billion gallons of water a day. This was a 13% reduction from 2005, the last time the data was collected by the USGS though the population of the United States increased by 4% to 313.0 million people in 2010. Part of this reduction might have been due to lingering effects from the recession, but overall water use peaked in 1980. 

The 2010 total water withdrawals were at the lowest level since before 1970. Freshwater use was 306 billion gallons/day, or 86 % of the total water use- salt water used was 48.3 billion gallons/day, or 14 % of total water use. Most of the salt water used is for cooling in power generation and 38% of freshwater used is also for power generation and is non consumptive. The water is returned to the source. Total fresh water used (including the water for power generation) was 306 billion gallons/day. Thermoelectric-power water use accounted for 45% of total water withdrawals for all uses, and freshwater withdrawals for thermoelectric power accounted for 38% of the total freshwater withdrawals for all uses. Fresh surface-water use was (230 billion gallons/day) were almost 15 % less than in 2005, and fresh groundwater use (76.0 billion gallons/day) were about 4 % less than in 2005.

Irrigation water use was 115 billion gallons/day in 2010 the lowest level since before 1965. Irrigation use accounted for 38% of total freshwater for all uses, or 61% of total freshwater withdrawals for all uses except thermoelectric power. Surface-water supplied 57% of the total irrigation withdrawals, 65.9 billion gallons/day or about 12% less than in 2005. Groundwater supplied 49.5 billion gallons/day for irrigation in 2010, about 6 % less than in 2005. While water used for irrigation decreased the USGS reports that 62,400 thousand acres were irrigated in 2010, an increase of 1.5% (950 thousand acres) from 2005. We became more efficient in water used for agriculture by increasing the use sprinkler and microirrigation systems. These types of systems are now used in 58% of irrigated lands in 2010.

Domestic water use includes indoor and outdoor uses at residences. Common indoor water uses are drinking, food preparation, washing clothes and dishes, bathing , and flushing toilets. Common outdoor uses are watering lawns and gardens or maintaining pools, ponds, or other landscape features in a domestic environment. Domestic water is either self-supplied or provided by public suppliers. Self-supplied domestic water use is typically withdrawn from a well, or captured as rainwater in a cistern. Domestic deliveries are provided to homes by public suppliers through community water systems. Public-supply water use in 2010 were 42.0 billion gallons/day, 5% less than in 2005. This was the first decline in public-supply water use since the USGS began estimating national water use in 1950.

An estimated 44.5 million people in the United States, or 14 % of the population, provided their own water for domestic use in 2010 in Virginia this is higher estimated by Virginia Tech at 21% though representing only 16% of domestic water used. (People with wells use less water for outdoor uses.) These self-supplied withdrawals were estimated at 3,600 million gallons/ day, in Virginia with a population of 8 million private wells supplied 124 million gallons/day in 2010. Nearly all (98 %) of these self-supplied water were from fresh groundwater sources. Self-supplied domestic water withdrawals are rarely metered or reported; typically this use is calculated by multiplying an estimate of the population not served by public supply by a coefficient for daily per capita private well use.
from USGS

In 2010, more than 50% of the total water use in the United States was accounted for by 12 States. The largest users of water were California and Texas which are the two largest states in the nation. California accounted for about 11% of the total water use and 10% of freshwater use in the United States. California predominantly uses water for irrigation. Texas accounted for about 7% of total water use, predominantly for thermoelectric power generation (a significant portion that is exported to California a state that imports 33% of its electric supply), irrigation, and public supply.

Monday, October 16, 2017

Grass-fed Beef and Greenhouse Gases

Grazed and Confused, a report released this month by the Food Climate Research Network (FCRN) led by Tara Garnett. The report essentially looks at greenhouse gas emissions and soil carbon sequestration in relation to beef and dairy production for human consumption. The report focuses exclusively on greenhouse gas emissions and attempts to determine if the grass-fed beef can sequester enough carbon to benefit the planet or if it is necessary to eliminate beef from the human diet to save the planet. 

Ruminants (mostly beef cattle) are blamed by environmental literature, the popular press and media and, increasingly, public for a significant portion of global warming. Extremists of this view believe that giving up beef will reduce the carbon footprint of mankind more than eliminating cars. Others believe that the sequestered carbon from pasture raised grass-fed beef can save the planet. The scientists tried to determine how much if any carbon is sequestered by grass-fed beef on net.

I should mention here that for decades what beef we eat is grass-fed. I started buying grass fed beef back in the 1990’s when I was doing environmental evaluations of farms, dairies and concentrated animal feed operations (CAFOs). I will not go into the details of that work that would shock most people; however, lets just say that my concerns for the animal welfare, mad cow disease, and environmental impact of CAFOs pushed me to buy my meat from the first sustainable farm I inspected. Today, in retirement, I continue to buy off the grid, sustainable, grass-fed beef from Polyface Farms here in Virginia.

Cattle that are grass-fed spend their entire lives grazing eating grass and forage that grows in the pasture. In addition, hay and silage which is just compacted grass are used to supplement in winter. Grass-fed beef require more land for pasturing as well as good management of the grazing to avoid over grazing the fields. This type of farm management protects our land and water resources. According to a study by Consumer Reports in 2015 found that conventional beef was twice as likely to be contaminated with these antibiotic resistant bacteria as more sustainably produced meat and three times more likely to be contaminated with the “superbug” bacteria as grass-fed organic meat.

Conventionally raised beef is where young cattle are shipped to feedlots where they are restricted in space and fed mostly corn and soybeans for several months to a year. They are also given antibiotics and other drugs to promote weight gain and prevent disease. In addition, they are sometimes feed other junk such as candy and feed that contains animal production waste. The animals in feedlots are crowded into pens; the average feedlot in the U.S. houses about 4,300 head of cattle, according to Food & Water Watch’s 2015 Factory Farm Nation Report.

Most academic studies have conclude that ruminant products, most commonly beef but also include goats, sheep, deer and others are the most emissions-intensive of all animal products, and within ruminant production systems, “conventionally raised” animals are the worst. However, that only measures greenhouse gas emission. Ruminant animals are actually rather miraculous and part of the planet’s ecology. Cattle and other ruminants can be raised on land unsuited to other food-producing purposes and on grain by-products from brewing and other food activities. In mixed a farming system the animals recycle nutrients and re-fertilize soils.

On the downside, ruminants emit large quantities of methane, use vast tracts of land, and are held responsible for a host of environmental ills, most notably deforestation and biodiversity loss, as well as the pollution of soils, air and water. Methane is a powerful greenhouse gas, but it has a shorter atmospheric life span than carbon dioxide (CO2). The effect of a given pulse of methane is temporary, unless replaced by another pulse. In contrast CO2’s warming effects are weak, but permanent. The next bit of CO2 emitted adds to the warming effects of all the CO2 emitted previously (except that absorbed by plants or other sequestered). So, because of their differing lifespans, a constant emission of methane from constantly replaced herd of cattle is therefore equivalent to one-off release of CO2.

The report , Grazed and Confused, found that the relationship between soil carbon sequestration and grazing intensity is complex. In soils that are not in equilibrium and where climate and other agro-ecological factors are right, light to moderate intensity grazing tends to promote sequestration of carbon overall. The scientists found some evidence to suggest that in some cases, grassland can store more carbon than forests. Thus, keeping ruminants on the land can achieve greater sequestration than removing them altogether and allowing woody vegetation to encroach.

However, the scientists state that on many lands, reversion to their natural wooded state would likely achieve higher levels of sequestration than would grazing although the loss of food from the grazing animals has to be compensated for elsewhere. The scientists also found that overgrazing damages soils, leads to soil carbon losses and undermines the organic matter in the soil and the soil overall health and fertility.

Overall the report found that grass-fed beef is not the magic bullet that will stop CO2 from building up in the atmosphere. However, as the scientists point out there are good reasons to build soil organic matter by pasturing livestock: soils rich in carbon foster soil fertility and health and a properly managed pasture with the livestock excluded from rivers and streams protects our waterways from contamination. The “conventional” livestock systems that operate today have caused an enormous amount environmental damage. Forests have been cleared, species driven to extinction, air and surface water polluted, and we have released vast quantities of greenhouse gases into the atmosphere.

Animal farming has also brought humanity huge benefits- It provides food that is highly nutrient dense, and very tasty. Farm animals can convert grass and silage that humans cannot eat into food that we can. When population densities were or still are sufficiently low and land abundant, livestock plays an important role in transferring nutrients from grasslands and onto cropland via their manure. The problem is there are over 7 billion people on earth none of whom want to be poorer or have less.

If you would like to watch the videos (which total more than an hour) here are the links:

Wednesday, October 11, 2017

GRACE Satellite Dies

from NASA
In September scientist lost contact with the GRACE-2 satellite. Contact was restored, but another battery cell had failed. GRACE is nearly out of fuel and the ability to store the energy collected by its solar panels when it is in earth shadow. Little power beyond the active solar collectors remains. The scientists put her on standby and in the next weeks she will complete her final data collection in full sun along the terminator line between night and day.

Launched in March of 2002 as the second mission under the NASA Earth System Science Pathfinder (ESSP) Program, the Gravity Recovery and Climate Experiment twin satellites were designed for a five years mission life. They have operated for 15 years far more than expected, though scientists had hoped they would continue to operate and collect data until their replacements, GRACE-FO (follow on), were launched, but GRACE-FO has been delayed.

The decommissioning of the GRACE satellites will begin in November when one of the satellites is moved to eliminate any chance it could collide with the other, followed by steps to render the spacecraft inert. The spacecraft will make an uncontrolled reentry (crash) in early 2018, with the exact time dependent on solar activity and its effects on the Earth’s atmosphere.

GRACE is a joint partnership between the National Aeronautics and Space Administration (NASA) in the United States and Deutsche Forschungsanstalt für Luft und Raumfahrt (DLR) in Germany. GRACE consists of two identical twin satellites that fly about 137 miles (220 kilometers) apart in a polar orbit 310 miles (500 kilometers) above Earth. GRACE maps Earth's gravity field by making accurate measurements of the distance between the two satellites, using GPS and a microwave ranging system. This allows scientists all over the world an efficient and accurate way to map Earth's gravity field. The replacement pair of satellites known as GRACE-FO will also be a joint German-American project, and are similar to the original GRACE spacecraft, but with the addition of a laser interferometer for more accurate measurements.

In January, NASA and the German Research Centre for Geosciences announced that a SpaceX Falcon 9 will carry the two GRACE-FO satellites as well as five Iridium Next communications satellites into low earth orbit. A launch date for the joint Iridium Next/GRACE-FO mission has not been set, but it is expected to occur in early 2018. NASA’s fiscal year 2018 budget proposal, published in May, projected a February 2018 launch of GRACE-FO.

The information gathered from the GRACE mission have allowed scientists to track the distribution and flow of mass within Earth and its surroundings- changes in water. The gravity variations studied by GRACE include: changes due to surface and deep currents in the ocean; runoff and ground water storage on land masses; exchanges between ice sheets or glaciers and the ocean; and variations of mass within Earth. Advances in hydraulic modeling with data from the satellites, make it possible to construct accurate and holistic picture of freshwater availability, across the globe as well as measure sea water.

GRACE data has provided a global picture of water storage trends for over a decade and could be an invaluable tool for understanding water resource availability. The GRACE mission is able to monitor monthly water storage changes within river basins and aquifers that are 77,000 square miles or larger. While this area may be too large for community water management, this information could someday be used to develop a unifying principal of cross border water resource allocation. The first use has been to study the trends on groundwater in various regions during this period.

Observing the groundwater buried beneath layers of soil and rock was almost impossible until, the twin satellites GRACE were launched in March 2002. At the time few believed the satellites could measure changes in groundwater, but thanks to work of Dr. Jay Famiglietti and his graduate student Matt Rodell, who were working at that time at the University of Texas at Austin (UT-Austin) the techniques for measuring groundwater using the GRACE satellites were developed and proven. Expanding on this earlier work is additional work by Alexandra S. Richey, Brian F. Thomas, Min-Hui Lo, John T. Reager, James S. Famiglietti, Katalyn Voss, Sean Swenson, and Matthew Rodell and I’m sure others that I have missed.

Monday, October 9, 2017

Global CO2 Emissions Held Steady in 2016

From IEA

As we saw last week world consumption of energy has continued to increase as the world economy continues to grow. According to data from the BP Statistical Review of World Energy (published annually) and the U.S. Energy Information Agency and the International Energy Agency (IEA) world consumption of fuel for energy production (as measured in millions of tonnes of oil equivalents) has increased 2.2% over the last three years, while the global economy grew 3.1% though global energy-related carbon dioxide emissions were flat for a third straight year in 2016.

Global emissions of CO2 equivalents from the energy sector stood at 32.1 gigatonnes last year, the same as the previous two years. Scientists have welcomed this as a signal that energy use and CO2 emissions are decoupling from economic activity. This good news was the result of growth in renewable power generation, switches from coal to natural gas for power generation and improvements in energy efficiency.
CO2 Emissions by Country taken from Statista
Carbon dioxide emissions declined in the United States and China, and were stable in Europe, offsetting increases in CO2 emission in most of the rest of the world. The biggest drop in CO2 emissions came from the United States, where carbon dioxide emissions fell 3%, or 160 million tonnes, while the economy grew by 1.6%. The decline in CO2 emission was driven by an increase in the use of natural gas from shale displacing coal to provide electricity and an increase in renewable power. CO2 emissions in the United States in 2016 were at their lowest level since 1992. This is true though the economy grew by 80% over this time frame.

In China, CO2 emissions fell by 1% last year while their economy was reported by the government to have grown by 6.7%. There were several reasons for this trend: an increasing share of renewables, nuclear and natural gas in the power sector, but also a switch from coal to gas in the industrial and buildings sector that was driven in large part by government policies combatting the horrible air pollution in their cities.

Two-thirds of China’s electricity demand growth, which was up 5.4%, was supplied by hydropower and nuclear. Five new nuclear reactors were connected to the grid in China, increasing its nuclear generation by 25%. According to IEA the growth in natural gas use in China has been significant and due mostly to air-quality measures to fight pollution. The share of natural gas in the global energy mix is approaching 25%, but in China it is 6% and in India just 5%. Changing from coal to natural gas in China and India could reduce global emissions significantly.

In the European Union, emissions were largely stable last year as gas demand rose about 8% and coal demand fell 10%. Growth in renewables continued, but provide a small impact. The United Kingdom saw a significant coal-to-gas conversion in the power sector, thanks to cheaper gas.

Thursday, October 5, 2017

Monsanto's Dicamba Resistant Seeds

In 2015 the U.S. Department of Agriculture (USDA) allowed the sale of seeds that have been genetically engineered to tolerate dicamba, a selective herbicide. Monsanto introduced a new product called Xtend a genetically modified soybean seed that is resistant to the herbicide. Dicamba is already registered (approved by the EPA) for uses in agriculture, on corn, wheat and other crops. Dicamba is also registered for non-agricultural uses in residential areas, and other sites such as golf courses, mainly to control broadleaf weeds such as dandelions, chickweed, clover and ground ivy.

One of the main concerns about genetically engineered crops such as Roundup Ready crops and now the new genetically modified soybean and cotton seeds that are resistant to dicamba and 2,4 D is the development of weeds and other plants that are also resistant to the pesticides. Glyphosate (N-phosphonomethylglycine), the active ingredient in the herbicide Roundup is also manufactured by Monsanto and is the most popular herbicide in use today in the United States, and throughout the World. Americans spray an estimated 180-185 million pounds of the weed killer, on their yards and farms every year.

The massive adoption of genetically engineered resistant crops in soybean-, maize and cotton-growing regions of the United States has resulted in evolution of glyphosate-resistant weeds. The first reported resistant weed was in 2001, Conyza canadensis L. This occurred after more than 25 years of glyphosate use. However, the development of resistant species of weeds has speeded up. There are now several known glyphosate-resistant populations of the very vigorous, highly competitive and economically damaging ragweeds Ambrosia artemissifolia L. and Ambrosia trifida L.

Researching this scientists found that If there is a sufficiently diverse system of weed management, herbicide resistance may evolve only very slowly or not at all. However, the reality is that most farmers using Roundup resistant seeds rely on glyphosate alone, with markedly reduced diversity in other weed management tools historically used like burndown, glyphosate use before crop seeding, or physical tillage were found to minimize glyphosate-resistant weeds, but they increased runoff of pesticides and soil. These methods were abandoned to the easier and no till method of spraying once the crop emerges. The result is that Roundup is not working so well anymore. So, Monsanto has come out with their new product With the new dicamba and 2,4 D resistant seeds.

The New York Times reports that the expanded use of dicamba is damaging nearby traditional crops through vaporization and  pesticide that is carried on the wind. That is the first problem to be seen. The development of weeds and other plants that are also resistant to the pesticides will happen. Right now dicamba kills weeds that can no longer be controlled by Roundup. In the long run it is likely that weed resistance to dicamba will increase. There are more sustainable methods of weed control.

Monday, October 2, 2017

World Energy Use 2016

Energy is the basis of the world economy and the use of fossil fuels to produce energy releases greenhouse gases. So lets take a look at energy consumed world wide. According to data from the BP Statistical Review of World Energy (published annually) and the U.S. Energy Information Agency world consumption of fuel for energy production (as measured in millions of tonnes of oil equivalents) has increased by about 50% over the last 20 years. The good news is that over that time renewables have increased from less than 1% to 3.2% of the energy produced. In 2016 hydro-electricity, nuclear power and renewable sources accounted for 14.5% of the energy consumed and these sources produce no greenhouse gases. Take a look at the world and then a more granular look at the energy used in some countries.
from the BP Statistical Review of World Energy 2016

As you can see above the use of all types of energy with the exception of nuclear has continued to grow year after year. 
Energy use in the United States, the Russian Federation and Europe appears to have leveled off and even decreased a bit over the past decade. Take a look at the relative size of the nations in terms of energy consumed. 

China has the largest absolute amount of renewables and hydro-electric sources of energy, but they are so much larger an energy user than any other country, representing 23.3% of the energy used globally that  taking a look at the percentages tells another story.

As you can see above Germany has the largest percentage of energy consumed in the country coming from renewables followed by the United Kingdom and Brazil. France has the highest percentage of energy consumed produced by nuclear power; and Canada and Brazil get more than a quarter of their energy from hydro-electricity. China gets more than 60% of the energy from coal and India gets more than 56% of their energy from coal. The oil producing nations and the car centric western nations all get huge amounts of energy from oil.