Monday, May 30, 2011

Choosing the Right Heat Sink for a Geothermal Heat Exchanger

According to the US Department of Energy the most effective type of heat pump is the geothermal heat pump, GHP, more accurately called ground-source heat pumps. These systems have been proven capable of producing large reductions in energy use in buildings. A study by the U.S. Environmental Protection Agency (EPA) comparing the major HVAC options for residential applications determined that GHPs were the most energy efficient and environmentally benign option. The overall performance of these systems will be to a large extent determined by selecting the ideal heat sink for your site and sizing your heat sink and system correctly. Only about 60,000 GHP units are installed each year in the combined US new built and retrofit market. The number is so small because the market is fragmented, the total systems are difficult to understand, the installation costs appear to be about twice the costs of less efficient system, and the distribution and installation network is inefficient. Better understanding of all elements of these systems is the first step in choosing a GHP.

In winter GHPs collects the Earth's natural heat from a heat sink, typically that is through a series of pipes, called a loop, installed below the surface of the ground or submersed in a pond or lake. Fluid circulates through the loop via an electric pump and carries the heat to the house. There, an electrically driven compressor and a heat exchanger concentrate the Earth's energy and release it inside the home at a higher temperature. Ductwork distributes the heat to different rooms. In summer, the process is reversed. The underground loop draws excess heat from the house and allows it to be absorbed by the Earth. The system cools your home in the same way that a refrigerator keeps your food cool by drawing heat from the interior, not by blowing in cold air.

As you may have experienced in a cave, the temperature at least six feet beneath ground surface is cooler in summer and warmer in winter than the ambient temperature. Using this temperature as its source the GHP can operate within its most efficient range for heat transport. The coefficient of performance or COP, of a GHP (or any heating and/or air conditioning unit) is essentially a measurement of the amount of work (either electricity or other source of power) necessary to change the temperature in the desired direction. A theoretical maximum achievable COP would be 7.8 on the usual design parameters. Test results of the best systems are above 5.0. However, when looking at cost savings on an installed unit this savings would be reduced by the energy needed to operate the pumps for the water and/or antifreeze through the piping systems.

The typical GHP has a water loop heat sink installed either horizontally or vertically. Horizontal ground loops are usually the most cost effective when trenches are easy to dig, the size of the yard is adequate and there is adequate soil. Workers use trenchers or backhoes to dig the trenches six feet below the ground in which they lay a series of parallel plastic pipes or loops. They then backfill the trench. Fluid runs through the pipe in a closed system. A typical horizontal loop will be 400 to 600 feet long for each ton of heating and cooling.

The vertical loop is used where there is little yard space, when surface rocks make digging impractical or the heat exchange properties of the rocky soil are unacceptable, or when you want to disrupt the landscape as little as possible. Vertical holes are typically 150 to 450 feet deep and contain a single loop of pipe with a U-bend at the bottom. Each vertical pipe is then connected to a horizontal underground pipe that carries fluid in a closed system to and from the indoor exchange unit. Vertical loops are generally more expensive to install than horizontal loops, but require less piping than horizontal loops because the Earth's temperature is more stable farther below the surface. The performance of these heat sink systems can also be enhanced by the presence of groundwater to improve the thermal transport properties of the water loop.

These heat sink systems whether vertical or horizontal have two loops: the primary refrigerant loop is contained in the GHP cabinet where it exchanges heat with a secondary water loop that is buried underground. They are thus called water loop systems. The secondary loop is generally HD polyethylene pipe and contains a mixture of water and an anti-freeze. After leaving the GHP, the water flows through the secondary loop outside the building to exchange heat with the ground before being returned to the building. In the extremes of weather, they efficiency of the GHP system can be negatively impacted by the water in the secondary loop’s ability to loose or gain enough heat.

The secondary loop is placed deep enough below the surface (and frost line) that the temperature remains relatively stable. Siltstone, balls bluff and other rocky soil are a poor medium for temperature transport and HD polyethylene is not an efficient heat transport medium. Loop systems installed in wet ground or in water are significantly more efficient than drier ground loops since it easier to move heat in water than air, solids, sand or soil because there is better surface contact.

A variation on the ground loop duel system is the direct loop system. The refrigerant leaves the GHP cabinet, and is pumped directly through a loop of copper tubes buried underground, and exchanges heat with the ground before returning to the pump. The name "direct exchange" refers to heat transfer between the refrigerant and the ground without the use of an intermediate fluid. Heat transfer takes place through the piping wall. It is best to use an environmentally friendly anti-freeze like denatured alcohol or methane because all these systems will someday fail and a simple and easy remediation should be planned in advance. Direct exchange heat pumps are not to be confused with “water loop heat pumps" since there is no water in the ground loop. Ground loop heat pumps have a higher efficiency than the water loop systems.

A groundwater or open loop system is the most efficient in terms of heat transport. These systems were originally designed to pump natural water from a well or body of water into a heat exchanger inside the heat pump. Heat would be either extracted or added depending on the season, and the water is returned to a separate injection well, or body of water. The supply and return lines must be placed far enough apart to ensure thermal recharge of the source. These systems were subject to limescale clogging or fouling if the water contains high levels of salt, calcium carbonate, iron and or magnesium, iron bacteria or hydrogen sulfide. In addition, these open-loop systems may drain aquifers or contaminate wells.

A standing column well system is a specialized type of open loop system. According to Dr. Zheng Dong O’Neill who has done extensive research on the topic, though there were only about 1,000 standing column systems installed in the United States in 2005 these systems utilize a shorter borehole depth and have more stable water temperature so they are cheaper to install than a vertical loop system and are more efficient than the water loop systems. In standing columns water is drawn from the bottom of a deep well, passed through a heat pump, and returned to the top of the well. Heat is lost or gained from the water as it travels back down the well. This system because it utilizes direct water contact for the heat sink (which is really the bedrock) is more efficient. In addition, because the water is returned to the well there is limited impact on the groundwater system. A high density of these groundwater systems could potentially impact a groundwater basin.

The standing column system is ideal where the bedrock is near the surface and the soils are rocky so that the well casing required is less than 60 feet. The standing column well method is popular in residential and small commercial applications in the New England states and should be ideal for the geology in my backyard. I have a strong shallow aquifer that runs from Bull Run Mountain to the river behind my land. There are acres of woods between the house and the yard (that I own) to allow the aquifer to regain its natural temperature profile. My land is down gradient of all my neighbors with the river serving as a hydraulic barrier to the basin. Any additional wells I install down gradient of my own drinking water well will not impact any other homes. Access to the well location for the well drilling equipment is an important factor. Well drillers tend to want to locate the well where it is easiest to drill. Make sure that the location will not impact drinking water wells, and that the trenching for the connection to the unit in the house is at least six feet deep. If that trench is too long and too shallow you defeat any benefit of the geothermal system. This is also true for the vertical loop wells.

If flow and sizing are properly done, this type of groundwater system can potentially have some heat storage benefits. The idea is that heat is rejected from the building will raise the temperature of the well by a few degrees during the Summer cooling months can then be harvested for heating in the Winter months, thereby increasing the efficiency of the heat pump system. Of course if the temperature of the well is raised too much in the summer the efficiency of the cooling system just falls. As with closed loop systems, sizing of the standing column system is critical. The heat exchange in this system is actually with the bedrock, using groundwater as the transfer medium. A large volume of water flow is not required for a standing column system to work and the water is returned to the well so the net effect on the groundwater table should be negligible. However, if there is adequate water production and the groundwater is well recharged, then the thermal performance of the well system can be increased by discharging a small percentage of the system water flow during the peak summer and winter months.

Since this is essentially a water pumping system, standing column well design is the most difficult to obtain peak operating efficiency. The well designer and driller needs to be fully trained and certified in GHP systems to ensure that the system is properly designed and includes all essential design elements including system shut-off valves to install a system that operates at maximum efficiency. Since the number of national installation has been so limited, experienced well drillers are difficult to find. The American Society of Heating, Refrigerating and Air Conditioning Engineers, ASHRAE, has funded Dr. O’Neill’s research to model standing column wells in GHP systems. Finding a well driller who has been certified in GHP by ASHRAE is a place to begin.

Thursday, May 26, 2011

The Causes of Brownish or Dirty Well Water

The Virginia Master Well Owner Network (VAMWON) is an organization of trained volunteers dedicated to promoting the proper construction, maintenance, and management of private water systems (wells, springs, and cisterns) in Virginia. The Cooperative Extension Services in Virginia manages the program and have numerous publications and fact sheets that can help homeowners make educated decisions about their drinking water. The volunteers can help homeowners interpret their test results and make educated decisions about what treatment might be appropriate and desirable or appropriate solutions to problems..

VAMWON Notes from the Field are a series of stories of the questions and sometimes the solutions I’ve encountered as a VAMWON volunteer. The VAMWON volunteer or Agent can help you identify problems with the water system and provide information on suggested treatments options and other solutions. You can find your VAMWON volunteer neighbor through this link by entering your county in the search box.

I received the following in an e-mail “A week ago Monday we had slightly brown water. I called the landlord who came by to say he was having a plumber look at the well situation. He stated with all the rain we have been having it has had an effect on the well. Yesterday morning I noticed brown water again. I called the landlord who had the plumber call who parroted that all the rain had caused cloudy water.”

Before you call a plumber, well driller, or water treatment company you should test your water so that the problem can be properly diagnosed. It is cheaper to test your water than call a plumber and you need to understand what the real problem is to correct it. First, verify that both the hot water and cold water are both discolored. If the hot water only is discolored then the problem might be with rust the hot water heater. After determining that the brown water is coming from the cold water tap also, it is still possible that there is rust in the plumbing fixtures or the piping, but it would typically manifest in only one sink or tub and not uniformly throughout the house (unless the rust is in the main water pipe from the well). However, it is to be noted that when a water supply has been shut off for a period of time any rust in the systems is likely to be dislodged when the water supply is turned back on. This is true for wells and public supply water systems.

After rust in the household fixtures there are three likely causes for well water to be brown or brownish, surface infiltration, well collapsing or water level dropping or iron (and/or manganese) in the water. Earthquakes can also cause a change in water, either by loosening fine grains of silt and soil or lowering the water level. According the the US Geological Survey there is no rhyme or reason to which wells will be impacted by an earthquake, but time might restore your well. A complete water test to determine the source and extent of your problem and possible treatments or solutions should include tests for manganese concentration, iron concentration, iron bacteria, pH, hardness, dissolved solids as well as the tests for total coliform, fecal coliform and e-coli bacteria.

Surface infiltration of water is due to impaired pump and casing system. In this instance this would seem to be what the landlord was insinuating with the comment about all the rain. A properly functioning well with a sanitary well cap should not be impacted by rain. The pump system consists of the well cap, well, and grouting. Surface flooding, excessive rain or snow melt could flow down the casing area if the grouting is damaged or the well cap not sealed properly. This of course would also allow bacteria from the surface to enter the well. Testing the well for bacteria would determine if the water were safe to drink and would indicate if there was surface infiltration.

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. An inspection of the well and pump system might visually locate any obvious flaws but the presence of coliform surface bacteria would certainly identify where to begin looking.

The second likely source of brown water is from the well itself. It is typical in Virginia not to have well casing beyond 40-50 feet deep. The Balls Bluff Siltstone and red clay common to this area does not typically need a casing. The most common modern well installation is to have a pump that installed in the well and looks a little like an outboard motor on a stick. Changes in water level or supply could result in the pump pulling up a bit of mud or the pump could have wracked a bit and is hitting the side of the well hole. So that water that suddenly turns brown may indicate a problem with the well structure or water level.

The third likely source of brown water is iron (and/or manganese) in the water. As rain falls or snow melts on the land surface, and water seeps through iron-bearing soil and rock, iron can be dissolved into the water. In some cases, iron can also result from corrosion of iron or steel well casing or water pipes. Iron can occur in water in a number of different forms. Iron is harmless, but can affect taste and use of water. An appropriate response to the presence of iron is to install the right treatment system.

The type of iron present is important when considering water treatment. Water that comes out of the faucet clear, but turns red or brown after standing is “ferrous” iron, commonly referred to as “clear-water” iron. Water which is rust colored, red or yellow when first drawn is “ferric” iron, often referred to as “red- water” iron. Iron can form compounds with naturally occurring acids, and exist as “organic” iron. Organic iron is usually yellow or brown, but may be colorless. A combination of acid and iron, or organic iron, can be found in shallow wells and surface water. Although this kind of iron can be colorless, it is usually yellow or brown.

Finally, when iron exists along with certain kinds of bacteria you may get bacterial iron that leaves a reddish brown or yellow slime that can clog plumbing and cause an offensive odor. You may notice this slime or sludge in your toilet tank when you remove the lid. Before you attempt to solve any water problem that appears to be iron-related, it is important to have your water tested. A complete water test to determine the extent of your iron problem and possible treatment solutions should include tests for iron concentration, iron bacteria, pH, dissolved solids, hardness as well as the tests for total coliform, fecal coliform and e-coli bacteria. The test results properly interpreted will allow you to address the underlying problem and spend your money to correct the right problem.

Monday, May 23, 2011

Water became Cloudy or Dirty Looking–VAMWON Notes from the Field

The Virginia Master Well Owner Network (VAMWON) is an organization of trained volunteers dedicated to promoting the proper construction, maintenance, and management of private water systems (wells, springs, and cisterns) in Virginia. The Cooperative Extension Services in Virginia manages the program and have numerous publications and fact sheets that can help homeowners make educated decisions about their drinking water. The volunteers can help homeowners interpret their test results and make educated decisions about what treatment might be appropriate and desirable or appropriate solutions to problems..

VAMWON Notes from the Field are a series of stories of the questions and sometimes the solutions I’ve encountered as a VAMWON volunteer. The VAMWON volunteer or Agent can help you identify problems with the water system and provide information on suggested treatments options and other solutions. You can find your VAMWON volunteer neighbor through this link by entering your county in the search box.

A private well owner located in the Manassas area of Prince William County contacted me through the Master Well Owner Network. I received the following request by e-mail “I am wondering if you can help me in regard to my well. I have concerns regarding the set up/layout of my current well and I would like to become a more educated and responsible well owner. Could you please let me know what assistance if any you may be able to provide.”

I received the e-mail while I was on vacation, but it sounded like a simple request for information and I assumed that I could just send a couple of basic articles to a new homeowner and have handled the inquiry promptly. People rarely contact the VAMWON out of the blue, there is usually a precipitating event. A home purchase, or a change in their water quality. So I called the homeowner to ask why he called. Turns out he had owned the home for several years and suddenly at the end of winter (when the snow melted) his water looked dirty. The homeowner had only tested his well when he purchased his home several years ago. The well test performed at purchase is typically a total coliform bacteria test. Passing is finding no bacteria present. So, either the well had been free of bacteria a few years back, or the seller had chlorine shocked his well ahead of the purchasers water test. Yes, it is easy hide a water problem if all that is being done is a test for total coliform bacteria.

I asked the homeowner, some basic questions to narrow down the problem. The home was an older home and the well was more than 20 years old. I asked him if he had a septic system and he told me no, he was on county sewer r the conversion reportedly happened when the school up the street was built. I confirmed that he was still on well water and that he knew the location of his well. I asked him to describe his well and what the homeowner described to me was a large pit made of cinderblocks or bricks with a well in the center and a metal hood on the well pipe.

In Virginia private wells were first regulated in 1990. The regulations were expanded by the Department of Health in 1993. Prior to that only public water supply wells and private wells constructed during the installation of a new or repaired septic system were regulated by the Department of Health. The vast majority of the private wells in Virginia were constructed before the regulations and there is no requirement that these older private wells comply with current regulations. If your home drinking water is supplied from a private well, you are responsible for ensuring that your water is safe to drink. Unlike public drinking water systems, no one is ensuring your well water is safe to dink but you. Groundwater, the source of well water is a dynamic system and subject to change, if your water tested fine in the past is no guarantee that is free from contaminants now. In addition, several water tests can provide clues to what is happening to your water system.

The old well at my parent’s house was built in an earthen pit with a lid. I used to hide in it when we played hide and seek. 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. Not having a sanitary cap on a well head was the most obvious problem described to me by the homeowner and remedying that problem might eliminate the infiltration. A second step would be to eliminate the well pit by extending the casing above grade and installing a pitless unit. There are adaptor units available for this and this has been successfully done at many sites. This will only work if the well itself is sound and the water supply unimpaired. If the homeowner’s well cannot be adapted and a sanitary water supply obtained, then in his case it may not make economic sense to drill another well, but instead the better choice might be to connect to city water since the water main runs to the end of his street. Before making a decision the water should be tested to make sure that the only contaminants appear to be from infiltration.

The water should not be consumed until it is tested. In truth infiltration problems are typically happen after snow melts or in the heavy rains of spring and often clear up later in the season. The dirty cloudy appearance of the water might clear up on its own, but the well must be disinfected and at the minimum a sanitary seal well cap installed. After any problems, or work on a well-installing a cap or even an extension to bring the casing above grade, you need to ensure that the well is treated with chlorine to disinfect it, then wait two weeks and test the water again to make sure that the water supply is sanitary without the chlorine shock. Testing your water, chlorine shocking and retesting wells to make sure that your water supply is potable are your responsibilities and essential to your health and the health of your families especially infants.

When I called to follow up, a few weeks later I discovered that the water had “cleared up” and the homeowners were too busy with their new baby to deal with that problem. I did not ask if they were still drinking bottled water, but I did something I do not like to do, I gave him the name, phone number and contact person to speak to at the well driller I use these days. I told him what to ask about and offered to come out to his house and check things out and include his home in the batch of home tests I am taking for an HOA. I negotiated a discount from the laboratory for the group. It is irresponsible as a parent to ignore a water problem.

Thursday, May 19, 2011

The Mississippi River and the Sustainability of the “American” Approach

For weeks we have watched as heavy spring storms and winter snow melt have combined to raise the Mississippi beyond flood levels. The crest of the flood waters has rolled down the Mississippi River, a natural disaster in slow motion. To prevent the breach of the levee system protecting the cities and towns along the river the U.S. Army Corps of Engineers have activated the approved and existing flood control plan which is to protect the levee system and cities by opening the open the Bonnet Carré Spillway and the Morganza Floodway in Louisiana after blasting a 2-mile-wide hole in a levee in Missouri to open a floodway, dropping water levels but also submerging 130,000 acres of prime farmland. Crops are flooded, homes are lost, the small towns sacrificed to the cities. It is sad to contemplate the loss these families have experienced; nonetheless, New Orleans and Baton Rouge remain dry and the levee system intact. When the flood waters recede, commerce on the Mississippi will resume.

The Mississippi River has the third largest drainage basin in the world, after the Amazon and Congo Rivers. It is reported to drain more than 1,245,000 square miles, and includes all or parts of 31 states and two Canadian provinces. Waters from as far east as New York and as far west as Montana contribute to flows in the lower river. The Mississippi is a navigation artery of great importance to the nation's transportation system, carrying an ever-growing commerce in a cost effective and sustainable way. In addition the River supplies water for the cities and industries that have located along its banks.

Major floods of the Mississippi have occurred in 1882, 1912, 1913, 1927, and 1937. The flood of 1927 was the most disastrous in the history of the Lower Mississippi Valley. An area of about 26,000 square miles was inundated. Levees were breached, and cities, towns, and farms were laid to waste. Crops were destroyed, and industries and transportation paralyzed. Over the next decades the flood control system and flood control plan to activate during times of excessive river flow when the system is endangered was developed. The whole goal of this system was to protect the cities and the shipping channel from destruction.

The four major elements of the Mississippi River and Tributaries flood control system are: levees for containing flood flows; floodways which serve as relief valves for excess river flow but sacrifice a 5 mile wide strip of land adjacent to the Mississippi primary levee; channel improvement and stabilization for stabilizing the channel against the forces of turbulent flow and sediment movement in order to provide a navigable channel for commerce, and for protection of the levees system; and tributary basin improvements for major drainage and for flood control, such as dams and reservoirs, pumping plants, and emergency channels., and the like. This system serves to protect, but also tries to freeze the Mississippi shipping channel from geologic change. Over thousand of years, the lower portion of the Mississippi River has used different pathways as its main channel to the Gulf of Mexico across the delta region. Left to the natural forces of nature, a new main channel will form through river avulsion. However, the management of the flood control system has prevented this from happening.

The flood control system has worked for decades, but the price of the flood control system is high, to save the cities, towns, refineries and the shipping channel mean controlling the flow of the river. This record breaking flood caught the U.S. Army Corp of Engineers in the process of obtaining approval for changing its approach to flood management. For decades, the agency has focused on preventing floods, with the Mississippi flood-control system dating to the aftermath of the great flood of 1927. This summer, it expects to win federal approval for a policy it has begun phasing in over the past several years: allowing more flooding to occur, while working with local and state governments to manage development on surrounding land to reduce economic damage and loss when a flood happens.

In recent years, the goal has been to manage development on the flood plane. There are practical, engineering and cost limitations to being entirely dependent on a levee system that effectively channels all flow towards the river. There are limitations. The idea is not to dismantle the levee structures, but to use other techniques to prevent the river from getting so high. A natural flood plain would serve to absorb the storm surges. The problem in executing this kind of approach is maintaining a natural flood plain. In the twentieth century, building an impenetrable levee at any cost seemed possible and in truth it was easier to spend Federal funds rather than battle the political and lobbying forces to control development, but levees need to be maintained and expanded with continued population growth and we do not plan, save or build for what the Army Corp of Engineers calls the “project flood” that we are experiencing now. Instead we have depended on the US have the resources to evacuate before the flood and then restore. Limitations on development of privately owned land have always been a tough sell in the United States; however, the challenges and costs look different in the twenty first century.

Monday, May 16, 2011

The Simple Steps to Comply with Virginia’s Alternative Septic Regulations

The Emergency Alternative Onsite Sewage System (AOSS) Regulations published on November 16, 2009 by the Virginia Department of Health were approved by Governor McDonnell on April 6, 2010, went into effect April 7, 2010 and will remain in effect until replace by the permanent regulations. Homeowners have only recently received letters informing them of the new regulations because there were several failed legislative challenges to the regulations.

The emergency regulations implement Legislation approved in 2009 (HB 2551, Acts of Assembly, 2009, Ch 220) that requires the Board of Health to promulgate emergency regulations to establish both performance requirements and horizontal setbacks necessary to protect public health and the environment for alternative onsite sewage systems. Though this legislation denied localities the ability to restrict use of AOSS in their counties, it requires all AOSS be properly maintained and spells out what that entails. Proper operation and maintenance of these systems is necessary to ensure that all AOSS function as designed. Uniform regulations throughout the Commonwealth might facilitate homeowner awareness and compliance with the regulations. The full text of the regulations can be read at this link. http://register.dls.virginia.gov/emergency_regs/e12v5613%2026-17.html

The Emergency AOSS regulations require professional operators certified and licensed by DPOR to operate and maintain all AOSS including those of single family homes in the Commonwealth of Virginia. Licensed operators are a small pool of individuals. Effective July 1, 2009, oversight of soil scientists and septic construction and repair companies was transferred from the Department of Health to the Department of Professional and Occupational Regulation (DPOR). Virginia law now requires that soil evaluators, installers, and operators of onsite sewage systems are licensed by the Board for Waterworks and Wastewater Works Operators and Onsite Sewage System Professionals at the DPOR. Prior to July 1, 2009, Virginia law did not require a license to practice as an onsite sewage system installer or operator. Because the program is relatively new, the DPOR compliant history will not provide much information, but you can obtain a list of licensed individuals.

Maintain a relationship with a licensed operator. This means you must hire a DPOR licensed operator. This “relationship” does not have to be a service contract, but many licensed operators require a contract to take on the obligations of the regulations and quite frankly, it does simplify things. A licensed operator is licensed by DPOR to operate and maintain all AOSS. Appropriate licenses are within the Onsite Sewage System Professionals category (soil evaluators, operators or installers) or Soil Scientists. Note that DPOR does not issue multiple licenses to individuals, so that someone who is qualified to install is also qualified to operate a system. You can go the DPOR website and look up the individual license holder, but it is important to know the individual license holder’s name which is not always the same as a company name. Many companies operate with several employees working under the license holder.

Have your AOSS operated and maintained by a licensed operator. As a homeowner if you are not licensed by the DPOR you are not allowed to maintain nor operate you own AOSS. The Virginia code requires the owner of an AOSS to have that system operated by a licensed operator, so you need to hire one of them to operate and maintain your system. That amounts to at a minimum one visit a year, but may be more depending on the type of system you have. The cost of my septic contract increased by 25% after the regulations were approved by the Governor. The operator (or someone who works for the license holder) will visit your home inspect, test and service the components of your system and will file a report on line with the Virginia Department of Health certifying the results.

Have an operator review the operation of the system at the frequency required by the regulations. The frequency of your required maintenance is actually on your AOSS operating permit, which you have probably never seen. Do not worry, if you have an “off the shelf” system it is probably once or twice a year. Typically, the manufacturer obtained general approval for commercially available AOSS (and that is most systems), the maintenance schedule is given in the standard homeowner’s manual (where to find that is below). My system operating instructions detail system inspections and adjustments every six months and filter cleaning every three months. The operator is required to perform the required system maintenance, fill out and file forms with Environmental Health detailing the operation and condition of the system and compliance with the required maintenance schedule. The operator is required to file a report (on-line) for all visits. A little note, if your system was custom designed by an engineer, you could have significant additional operating, maintenance and sampling requirements.

Have an operator collect any samples required by the Regulations. In addition to regular maintenance and inspection, all systems installed after April 7, 2010 and whose systems have a secondary treatment before the soil treatment area are required to have a grab sample of sludge taken and analyzed for BOD and, if disinfection is required, fecal coliform once every five years. Systems installed before April 2010 are grandfathered and do not require sampling (they were installed without sampling ports). Expect to pay at least a couple hundred dollars for this. Yes, it would be cheaper if you took the samples yourself, but you are not allowed to.

Keep a copy of the maintenance log provide by the operator on the property where the AOSS is located. Every time the operator visits your system to maintain and/or inspect it, they are required to fill out a form with the Virginia Department of Health on their on-line reporting system and send you or give you a form indicating what service they provided. I file all of these in a notebook with the Operations Manual, but my service company e-mails me the invoice/log entry so I have all items electronically stored.

Keep a copy of the Operations and Maintenance (O&M) Manual for the AOSS on the property, make it available to the health department on request and transfer the O&M Manual to any future owner. All manufactures of systems approved in Virginia have created O&M Manuals that you can access on line and print. I know this is the biggest waste of paper ever, but I’m not entirely convinced that the health department would accept an electronic copy should they happen to ask. Also, read it, it does give some useful tips on how to properly use your system. All the manuals from the standard state approved systems can be accessed at this link. http://www.vdh.virginia.gov/EnvironmentalHealth/ONSITE/manufacturersinstructions.htm (Go outside and read the name and model number off your system. It is on the power/circuit boxes bolted to the house.)

These requirements went into effect on April 7, 2010 and remain in effect until final regulations for O&M of alternative systems are in place. Compliance is simple, but expensive. Identify the type of system you have, print the manual, then identify a licensed operator in your area and hire them. (Check reference and comparison shop, cost is not always indicative of quality in an inefficient market.) Finally, keep all log visits to show that your system has been maintained as required.

Thursday, May 12, 2011

Arbor Day at Pace West School

On Wednesday, May 11, 2011 The Pace West School in Gainesville celebrated Arbor Day. I was fortunate to be able to participate on behalf of the Prince William Soil and Water Conservation District. Pace West will be moving by fall, so this year’s Arbor Day class each received a seedling to take home and care for. The seedlings came from the Virginia Forest Service.

Though Arbor Day is typically observed the last Friday in April, a day of tress is now observed around the world at different times based on ideal planting season. Wednesday, was a perfect day for planting trees in Gainesville, Virginia. Arbor Day was an early recognition of the need for sustainability in how we live on the earth.

Arbor Day was founded in Nebraska by J. Sterling Morton in 1872 when a million trees were planted in a single coordinated effort to counteract the deforestation that had occurred as trees were harvested to support the growth of the nation. In his speech to the school children who had planted and later cared for many trees, Mr. Morton described the great oneness of nature in all its parts. Man is dependent on plants for life, for the wealth, beauty and luxuriance of harvest fields, orchard fruits, forest glades, and for the recycling nutrients into the earth. Before the first Arbor Day, wood had been harvested, the lands stripped of trees, without planting to repair the waste. This had resulted in floods and droughts, infertile and barren soil, and even the extinction of entire communities as the land seemed to be used up and blown away across the prairie.

Each generation of humanity takes responsibility of the earth as trustees to hold until the next generation becomes the successors in trust. The next generation will inherit a very crowed earth in need of great care and stewardship. Trees are the first step in caring for the earth. We need to nurture and care for the trees so they in turn can sustain us. According to The Tree Folk “A single mature tree can absorb carbon dioxide at a rate of 48 lbs/ year and release enough oxygen back into the atmosphere to support 2 human beings.”

Forests which are really treed ecosystems now cover 10 million square miles of earth. There was a time when forests extended much further. Most of the cultivated and inhabited lands of today were once forests or estuaries. The demand to covert ever more land to agriculture to support the increasing human population causes the loss of the forest ecosystem and increased soil erosion and flooding. The loss of large portions of the rain forest is believed by some to be a major contributor to the increase in carbon dioxide in the atmosphere.

Trees can also reduce air conditioning and heating needs by providing shade and providing a wind shield for winter and reducing our overall use of carbon based fuels. Trees also act as natural pollution filters. Their canopies, trunks, roots, and associated soil filter polluted particulate matter out of the runoff flow towards the Chesapeake Bay. Trees also use and recycle nitrogen and phosphorus which are contributing to the decay of the Chesapeake Bay and its estuary.

Monday, May 9, 2011

Complying With Virginia Alternative Septic Regulations

At the end of April of this year Prince William County Environmental Health finally sent out letters notifying the owners of Alternative Onsite Sewage Systems, AOSS, that they are required to comply with the AOSS Regulations that went into effect April 7, 2010. Environmental Health is part of the county health district and implements the Virginia State Department of Health regulations. Though this legislation denied localities the ability to restrict use of alternative septic systems, it requires all AOSS be properly maintained. Uniform regulations throughout the Commonwealth might facilitate homeowner awareness and compliance with the regulations.

The letters from Prince William County Environmental Health outline (though I am afraid not entirely clearly) the six responsibilities of homeowners with AOSS. It is really very easy to comply, though not at all cheap. I have an O&M Service plan with one inspection and two service visits a year including all required reporting for $575 per year for the basic plan. Discounts are available from most companies if you get together a group of neighbors.

1. Maintain a relationship with a licensed operator. This “relationship” does not have to be a service contract, but many licensed operators require a contract to take on the obligations of the regulations and quite frankly, it does simplify things. A licensed operator is an onsite sewage system operators licensed by DPOR to operate and maintain all alternative onsite septic systems, AOSS. Appropriate licenses are any licensee within the Onsite Sewage System Professionals category (soil evaluators, operators or installers) or Soil Scientists. Note that DPOR does not issue multiple licenses to individuals, so that someone who is qualified to install is also qualified to operate a system. You can go the DPOR website and look up the individual license holder, but it is important to know the individual license holder’s name which is not always the same as a company name. Many companies operate with several employees working under the license holder.
2. Have your AOSS operated and maintained by a licensed operator. The Virginia code requires the owner of an AOSS to have that system operated by a licensed operator, so you need to hire one of them to operate and maintain your system. That amounts to at a minimum one visit a year, but may be more depending on the type of system you have.
3. Have an operator review the operation of the system at the frequency required by the regulations. The frequency of your required maintenance is actually on your AOSS operating permit, which you have probably never seen. However, with an AOSS system that the manufacturer obtained general approval for (and that is most systems), the maintenance schedule is given in the standard homeowner’s manual (where to find that is below). My system operating instructions detail system inspections and adjustments every six months and filter cleaning every three months. The operator is required to fill out and file forms with Environmental Health detailing the operation and condition of the system and compliance with the required maintenance schedule. The operator is required to file a report (on-line) for all visits.
4. Have an operator collect any samples required by the Regulations. In addition to regular maintenance and inspection, all systems installed after April 7, 2010 and whose systems have a secondary treatment before the soil treatment area are required to have a grab sample of sludge taken and analyzed for BOD and, if disinfection is required, fecal coliform once every five years. Systems installed before April 2010 are grandfathered and do not require sampling (they were installed without sampling ports).
5. Keep a copy of the maintenance log provide by the operator on the property where the AOSS is located. Every time the operator visits your system to maintain and/or inspect it, they are required to fill out a form with the Virginia Department of Health on their on-line reporting system and send you or give you a form indicating what service they provided. I file all of these in a notebook with the Operations Manual, but my service company e-mails me the invoice/log entry so I have all items electronically stored.
6. Keep a copy of the Operations and Maintenance (O&M) Manual for the AOSS on the property, make it available to the health department on request and transfer the O&M Manual to any future owner. All manufactures of systems approved in Virginia have created O&M Manuals that you can access on line and print. I know this is the biggest waste of paper ever, but I’m not entirely convinced that the health department would accept an electronic copy. Also, read it, it does give some useful tips on how to properly use your system. All the manuals from the standard state approved systems can be accessed at this link. (Go outside and read the name and model number off your system. It is on the power units bolted to the house.)

These requirements went into effect on April 7, 2010 and remain in effect until final regulations for O&M of alternative systems are in place. The letter you received requires you to engage a licensed operator in a “timely” manner. These requirements (with the exception of the sampling requirement only) apply to all AOSS. Compliance is simple, but expensive. I use my system as recommended by the manufacturer and EPA, keep a notebook of receipts and the O&M Manual and write checks.

Thursday, May 5, 2011

The Carcinogen Search–VAMWON Notes from the Field

VAMWON Notes from the Field are the stories of the questions I’ve encountered as a volunteer with VAMWON. The Virginia Master Well Owner Network (VAMWON) is an organization of trained volunteers and extension agents dedicated to promoting the proper construction, maintenance, and management of private water systems (wells, springs, and cisterns) in Virginia. The Cooperative Extension Services in Virginia manages the program and have numerous publications and fact sheets that can help homeowners make educated decisions about their drinking water. The VAMWON volunteer or Agent can help you identify problems with the water system and provide information on suggested treatments options and other solutions. You can find your VAMWON volunteer neighbor through this link by entering your county in the search box.

I received a homeowner inquiry from outside my region referred to me because of my quarter century as a chemical engineer working as an environmental consultant. The homeowner was trying to navigate the best way to have their water well tested and what to test it for. The homeowner was an organic farmer living within a farming community. Their property has been a working farm for over 100 years and was surrounded by other farm land. They had tested their well in the past, and it came back within the acceptable limits, but they lacked a complete list of everything that was tested for and it had been several years ago. What prompted their immediate interest was within the last month their cat and a dog were both diagnosed with cancer. Not the same type of cancer, but cancer, nonetheless. They wanted to test their water to make sure it was not the cause. Water testing is very expensive and they wanted me to help them determine what they should test for and to help them find as an affordable and appropriate testing package as possible.

Cancer is caused by changes in a cell's DNA – its genetic "blueprint". Some of these changes may be inherited from our parents, while others may be caused by exposures, which are often referred to as environmental factors. In addition, it is believed that certain environmental factors may “turn on” certain dormant viruses and other factors. Environmental factors can include a wide range of exposures, such as lifestyle factors including food and exercise, naturally occurring exposures, workplace and household exposures, and pollution.

Substances and exposures that can lead to cancer are called carcinogens. Some carcinogens do not act on DNA directly, but lead to cancer in other ways. Carcinogens do not cause cancer in every case. Substances labeled as carcinogens may have different levels of cancer-causing potential. Some may cause cancer only after prolonged, high levels of exposure. For any particular person, the risk of developing cancer depends on the person’s genetic makeup, how they are exposed to a carcinogen, the length and intensity of the exposure, and other often unknown factors. The methods of exposure are generally through skin, breathing, ingestion on food or dust (with small children and pets) and water.

There are more than 80,000 known chemicals and because there are far too many to test each one in laboratory animals, scientists use knowledge about chemical structure, information about the extent of human exposure, and other factors to select chemicals for testing. Even though it isn't possible to predict with certainty which substances will cause cancer in humans based on laboratory studies with other species alone, all known human carcinogens that have been tested in animals produce cancer in lab animals. Many carcinogens are identified not through testing, but through epidemiologic studies, which look at human populations utilizing statistics to determine which factors might be linked to cancer and often have limitations in identifying causality rather than association.

According to the International Agency for Research in Cancer, IARC, [ which is part of the World Health Organization; there are 432 substances that are today classified as known or possible carcinogens. To test the homeowner’s water for all these substances would be prohibitively expensive, but also not rational. In order to be exposed, there must be a likely source of the contamination. The water well draws from the groundwater and though it was widely believed in the past that groundwater was protected from contamination, this is not true. Obvious contamination sources, such as landfills, lagoons, and other waste facilities are easily identified. Sources not so easily recognized as potential contamination sources include agricultural, industrial, and mining operations, and naturally occurring processes such as salt water intrusion.

Gathering information from the homeowner was necessary to determine the likely sources of contamination. The homeowner was very well informed and had though about the potential source of groundwater contamination. She had focused her search on the pesticides used by her neighbors and had checked with the local distributor and farm agent to identify the most commonly used substance on the adjacent land.

Agricultural activities can cause degradation of the groundwater. Excessive use of fertilizers and pesticides or improper application or disposal of these substances can contaminate groundwater. Shallow groundwater can also be impacted by runoff of pesticides and improper well construction. Organophosphorus pesticides and herbicides were replaced in the 1930’s and 1940’s by the organochlorine chemicals that were later banned or fell out of use due to their tendency to bioaccumulate or cause long lasting damage to plants and animal life (most notably DDT, dieldrin, aldrine, and the components of Agent Orange 2,4,5 T and 2,4 D. In addition, improper management, storage and disposal of animal waste from manure piles, animal waste lagoons and feedlots (which are not common in Virginia) can contaminate groundwater with biological contaminates and nitrate. These are the direct contamination from agricultural activities.

However, other activities take place (or commonly took place) on agricultural properties. On farms it was quite common to dispose of waste by burying it, in doing so; we sometimes unwittingly contaminate ground water. Once buried, some wastes are forgotten and become more difficult to locate as time passes. Waste disposed of surface dumping in ravines also poses a threat, especially when rainwater or snowmelt seeps down through it into the groundwater. Because groundwater in many geologic formations moves slowly, a contamination problem can remain undiscovered for years or decades before the contamination plume reaches a well (or other outlet) where it is discovered. In addition in some types of geology ravines where dumping commonly took place are fissures that can run to the groundwater table.

Other sources of contamination on land with agricultural history are machinery use, fueling and maintenance. Many farms had underground fuel storage tanks that were simply abandoned over time. These abandoned tanks rust and release any residual fuel to the water and potentially to the groundwater. Farm equipment was maintained using solvents and oil. In the middle of the 20th century it was common to pour out dirty solvent and fuel on the ground or down the drain directly to the septic system and out into the groundwater. Cesspools, which directly disposed of untreated sewage wastewater into pits, are no longer permitted in Virginia, but were common in the past. Septic systems are not designed to treat pesticides, solvent and hydrocarbons and they will pass directly to the groundwater.

The homeowner in her research had determined that local farmers were using Round-Up (glyphosate), using aerial spraying extensively to keep weeds out of their fields. Glyphosate is the most widely used herbicide in the United States. Though it has long been claimed that the glyphosate broke down quickly in the environment to CO2, that has come into question and glyphosate and its similar first breakdown product appear to be far more persistent. Pure glyphosate has a low acute toxicity; however, when it is sold as a commercial herbicide it is combined with surfactants and other ingredients to make it more effective at killing weeds and potentially reaching other unintended targets. Studies show that the commercial products, such as Round Up, can be many times more toxic than pure glyphosate.

Two population studies in Sweden have linked exposure to glyphosate to Hairy Cell Leukemia and Non Hodgkin’s Lymphoma. The first study found a weak link associating non-Hodgkin’s lymphoma to recalled use of glyphosate... Another population study has found a higher incidence of Parkinson disease amongst farmers who used herbicides, including glyphosate. These are non-specific associations. Glyphosate is used with five different salts, and commercial formulations like Round-Up contain surfactants, which vary in nature and concentration. Japanese studies found acute toxicity from ingestion. More recent research suggests glyphosate induces a variety of functional abnormalities in fetuses and pregnant rats any may indicate a potential as precursors to cancer and birth defects.

The use of glyphosate containing herbicides to prevent weeds has spread rapidly after the banning of the previous organochlorine compounds including 2, 4 D and 2, 4, 5 T which together form Agent Orange and MCPA which caused persistent environmental damage. Glyphosate is a type of Organophosphorus herbicide that is believed to be far less toxic than the predecessor compounds. Our lack of true long term understanding of what these and other chemicals do to living organisms and the natural environment is stunning given the sheer volume of glyphosate used and the typical aerial application. In field studies glyphosate spray drift from aerial applications has been measured at up to 2,500 feet from the target site.

The other chemical currently in wide use amongst neighboring farms is Warrior T which is a synthetic pyrethroid, an insecticide. Natural pyrethroids are extracted from chrysanthemums. This class of insecticide is believed to be far less toxic and environmentally persistent than the organophorus and organochlorines they replaced. After discussing the cost and the studies that have been done by the homeowner decided to forgo this test.

I called a laboratory I had used in the past when doing site assessments and pricing for both Warrior T and Round-Up for the homeowner as well as identifying the WaterCheck package with pesticides that would scan her water sample for volatile organic compounds including common solvents and some of the components, additives and impurities of gasoline, historic pesticides, heavy metals, trihalomethanes, PCB and physical properties. In truth it is unlikely that the homeowner can identify a source of cancer for her pets, our knowledge of cancer is not that advanced. Also, dogs and cats in a farm environment are more likely to be exposed to pesticides and herbicides from ingestion during grooming. Nonetheless, regularly testing your own drinking water for chemicals that might be present is prudent to ensure a safe drinking water supply.

Monday, May 2, 2011

Residue from the Dishwasher –VAMWON Notes from the Field

VAMWON Notes from the Field are a series of stories of the questions and sometimes the solutions I’ve encountered as a volunteer with VAMWON. The Virginia Master Well Owner Network (VAMWON) is an organization of trained volunteers and extension agents dedicated to promoting the proper construction, maintenance, and management of private water systems (wells, springs, and cisterns) in Virginia. The Cooperative Extension Services in Virginia manages the program and have numerous publications and fact sheets that can help homeowners make educated decisions about their drinking water. The VAMWON volunteer or Agent can help you identify problems with the water system and provide information on suggested treatments options and other solutions. You can find your VAMWON volunteer neighbor through this link by entering your county in the search box.

Below is an email I received (my contact information is available through the VAMWON web site).
“I have another mystery, if you are agreeable to finding another solution. For several years, I have noticed that when I drink water out of my glassware, the water smelled "dusty"....which I assumed was the residue from the dishwasher detergent. I would try at different times to solve this problem by rinsing an extra cycle, or minimizing the amount of detergent. I am down to two tablespoons now. The dishes still get clean, but the smell persists.
(1) I assume this is not a dangerous occurrence.
(2) Is there another test that we should have included in our sample that we will take this week ...? “

The homeowner had just forwarded to me the analysis results from their most recent water testing. The homeowners have three grandchildren under the age of 3 year’s old living in their home so they have been testing their water regularly using the WaterCheck package available from National Testing Laboratories, Ltd. If your home drinking water is supplied from a private well, you are responsible for ensuring that your water is safe to drink. There are no requirements to sample and sample analysis can be quite expensive depending on what analyses are performed. The homeowner is responsible for paying for the sampling.

In the past the homeowner had told me that they had high iron and hard water and a treatment system, but the test results showed low iron and manganese and water that were not particularly hard. I questioned where the sample was taken and the homeowner assured me that they took the water sample from the back outside water spigot (after properly cleaning it) that is after the simple sediment filter but before the water softener. The water treatment company they consulted had reportedly tested their water and found high iron when they sold them the water treatment system that apparently consisted of a whole house fiber filter and a water softening system.
I was a little puzzled by the results and I had asked the homeowner to check their toilet tanks for a red or rust colored slime. They found no slime in any of the toilets, but did find a small amount of sediment in the bottom of each toilet that is a rusty red color and clouds up the water when swirled with a toilet brush. They also found a bit of milky colored substances around the black gasket that the flapper on multiple toilets. When she scratched off a bit with her fingernail, it floated up like tiny pieces of “corn starch.

What she described sounded like a precipitate (calcium carbonate, sodium chloride) its white color would indicate few impurities, minerals and impurities tend to add color to precipitates. Though it is possible that the water treatment company performed a coagulation test, but most people are honest though their test are often very limited in scope. Considering the problem assuming the water treatment company actually found iron before they sold the homeowner a treatment system and now the water tests were non-detect for iron I realized there could be a simple explanation given where the sample was taken. Particulate or colloidal (Ferric iron (Fe3+)) may be the form of iron present in the water supply. This form of iron appears as particulates in the oxidized form. Particles in suspension in the tap water result in water that has rust, red or yellow color when the particles settle.

One of the recommended treatments for iron is aeration followed by filtration – This method is effective for treating iron and manganese with a combined concentration of between 5 and 10 ppm. Air is mixed with passing water to oxidize the iron and/or manganese producing particles that can then be filtered out of the water by a fiber filter. When water leaves the well it is exposed to air that can have this effect depending on the flow rate and holding times in the system. The water then passes through a filter to screen out particles of iron and/or manganese. An oxidizing filter treatment system is the next level of filtration. It is effective in treating iron and manganese at combined concentrations of up to 15 mg/L. Because oxidizing filter units combine oxidation and filtration, they can be used to treat water with dissolved and/or particulate iron and manganese.

It appeared that the filter on the homeowners system was doing a decent job of removing the iron oxide particles. The more oxygen the water is exposed to before the filter, the better it works. So when the pump is working full out, there is less time for oxygenation in your pressure tank and your filter will be less effective. Retesting the water supply ahead of the filter could confirm this, but would be an additional cost. The effectiveness of the installed water softening system for iron removal is very limited. Iron and manganese present in combined concentrations of 5 ppm or less can usually be removed by using an ion exchange water softener. However, this is not an optimal removal method.

As for hard water, some University extension offices designate 125 ppm as the cut off for hard water others use 100 ppm. No matter which standard you use 120 ppm the level present in their water is only marginally hard. My own water is significantly harder and I do not treat. I just use detergent based soaps and lots of vinegar to treat the limescale. I just assume my hot water heater will be a short lifer. In addition, the water softening system might impact the life of your septic system. The salt reportedly reduces the life of the septic tank (www.watersystemscouncil.org ) and may impact the peat medium and soil in the drainage area. Also, softening can make your water slightly acidic and in that way reduce the life of all your fixtures. So softening becomes a trade off and is best only used if you prefer a slightly salty water residue. I believed that the residue on the dishes might be simply salt and suggested they try turning off their softener.

The homeowner chose to turn off their iron exchange water and found that the “dusty smell” and residue on the glasses disappeared. In addition, she claims to be much happier with the “feel” of the hard water.