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Make sure your well water is safe.

repairfinder — Fri, 24 Oct 2008 21:35:41 +0200

Forty-seven percent of the United States depends on ground water for
their basic drinking water supply. Having a basic understanding about
ground water quality will help ensure that your well is supplying
potable water for your household.

Along with human activities, water quality is affected by a
combination of natural processes. Most relate to chemical compositions
underground. However, other factors such as biological, physical, and
radiological conditions can affect water quality as well.

The National Ground Water Association recommends that water well
owners have their wells checked and tested by a certified and/or
licensed contractor every year to ensure water safety. You can find
these licensed contractors on Repairfinders.com

Hard Water

The most common problem associated with ground water may be
hardness, generally associated with an abundance of calcium and/or
magnesium dissolved in the water. Hard water has not been shown to
cause health problems, but can be a nuisance as it may cause soap curds
and deposits to form on pipes and other plumbing fixtures. Over time,
this can reduce the diameter of the pipes.

Calcium and magnesium are found in ground water that has been
exposed to certain rocks and minerals, especially limestone and gypsum.
When these materials are dissolved, they release calcium and magnesium.
Hard water is considered bad for your plumbing, but people with heart
or circulatory problems may want to consult their physician about
drinking softened water, because the softening process removes calcium
and magnesium, and adds sodium to the water.

Iron and Manganese

A “rusty” or metallic taste in water is a result of iron, and
sometimes manganese, in ground water. They not only create a bad taste,
but they also can stain pipes and clothing.

Iron and manganese are naturally occurring, and most ground water
has some amount of dissolved iron and manganese in it. It comes from
contact with minerals that contain iron, such as pyrite.

There are several treatment methods. Installing a water softener may
help if iron and manganese are present in low quantities and the
softener is designed for their removal. Aeration (the addition of
oxygen to the water), chlorination, and feeding ozone or hydrogen
peroxide can aid in the precipitation of iron, which it is removed from
the water by filtration. Potassium permanganate feed with manganese
greensand filters, and some recently designed synthetic media, will
remove iron and manganese, as well.

Nitrogen

Most nitrogen in ground water comes from the atmosphere. Some plants
can “attach” nitrogen from the atmosphere onto their roots. The
nitrogen not used by the plants is then released into the soil.

Nitrogen compounds also can work their way into ground water through
fertilizers, manure, and urine from farm animals, sewage, and landfills.

The most common forms in ground water are ammonia, nitrate, and
nitrite. Nitrates can be especially toxic to children under six months
of age. Exposure to ammonia also presents a health risk. It is toxic to
aquatic life such as fish, and it interferes with water treatment.

There are a variety of treatment methods to correct this problem,
including reverse osmosis systems with water softeners to remove
nitrates and nitrites, and oxidation to remove small amounts of
ammonia. However, treatment should be a last resort. Removing the
source of contamination is the first priority. You should also be sure
to protect the area around the wellhead from contamination by animals
or fertilizers.

Silica

Silica comes from the weathering of silicate minerals in the ground.
It causes no harmful effects to humans, but large amounts can cause
scaling in pipes that impacts water flow, and it can interfere with
iron and manganese removal.

Sulfur

Sulfur can occur in ground water in two forms: sulfides and
sulfates. Sulfides are naturally occurring in much of the United States
in limestone containing organic materials; ground water affected by
oil, gas, and coal deposits; in marshes and manure pits; and in the
byproduct of well-established iron bio films. Sulfates often come from
the dissolving of minerals, such as gypsum and anhydrite.

A “rotten egg” smell coming from your water indicates the presence
of hydrogen sulfide gas. Along with creating an unpleasant odor and
taste, sulfides cause corrosion to plumbing and darken water.

There are several methods for treating sulfur. Aeration, ozone,
hydrogen peroxide, and chlorine (best followed by filtration) are
effective against dissolved hydrogen sulfide or gas. A reverse osmosis
system, nanofiltration system, or a negative ion-exchanger also can be
effective in reducing sulfates. Filtration is necessary in combating
sulfur formation as a mineral or in bio films.

Total Dissolved Solids

TDS, as it is commonly known, is the concentration of all dissolved
minerals in water. It is the direct measurement of the interaction
between minerals and ground water.

TDS levels above 1000 mg/L will usually yield poor tasting water.
Levels above 2000 mg/L are considered undrinkable due to taste, and
levels more than 10,000 mg/L are defined as undrinkable.

Water softeners with a reverse osmosis system are effective in lowering the TDS to satisfactory levels.

Additional Treatment Information

For more information on water treatment methods, you should contact a well specialist. There are many listed on Repairfinders.com .
All it takes is a moment of your time, and remember that when it comes
to something as life sustaining as water, you do not want to hold for
tomorrow, what you should do today.

Do you know the difference between Cemen...

repairfinder — Thu, 18 Sep 2008 20:47:36 +0200

Today is such a beautiful day! I have always found Thursdays to be a bit boring, but today is such a nice day. I figured that since I am in such a good mood, we could do something “educational”. Instead of giving you the inside scoop today, I am going to give you information. Doesn’t that sound fun? Well let us get to it. Be prepared to learn a lot, because I know you do not know much about cement.

Many people talk about cement when they mean concrete.

Cement is a fine-grained compound that turns into a solid when mixed with water. Cement is used to bind mixtures of materials into a composite solid.

Concrete is a mixture of cement, sand and gravel. That is, cement is the glue of concrete. Now that we have made that clear, let us talk about cement. Cement begins with lime.

Lime, the First Cement

Lime is a substance used since ancient times to make useful things like plaster and mortar. Lime is made by burning, or calcining, limestone-and that is how limestone gets its name. Chemically, lime is calcium oxide (CaO) and is made by roasting calcite (CaCO3) to drive off carbon dioxide (CO2). That CO2, a greenhouse gas, is produced in great quantities by the cement industry.

Lime is also called quicklime or calx (from Latin, where we also get the word calcium). In old murder mysteries, quicklime is sprinkled on victims to dissolve their bodies because it is very caustic.

Mixed with water, lime slowly turns into the mineral portlandite in the reaction CaO + H2O = Ca(OH)2. Lime is generally slaked, that is, mixed with an excess of water so it stays fluid. Slaked lime continues to harden over a period of weeks. Mixed with sand and other ingredients, slaked lime cement can be packed between stones or bricks in a wall (as mortar) or spread over the surface of a wall (as render or plaster). There, over the next several weeks or even years, it reacts with CO2 in the air to form calcite again-artificial limestone!

Concrete made with lime cement is known from archaeological sites in both the New and Old World, some more than 5000 years old. It works extremely well in dry conditions. It has two drawbacks: Lime cement takes a long time to cure, and while the ancient world had lots of time, today time is money.

Lime cement does not harden in water but stays soft, that is, it is not a hydraulic cement. So, there are many situations where it cannot be used.

Ancient Hydraulic Cement

The Pyramids of Egypt are said to contain a hydraulic cement based on dissolved silica. If that 4500-year-old formula can be confirmed and revived, it would be a great thing. However, today’s cement has a different pedigree that is still quite ancient.

Around 1000 BCE, the ancient Greeks were the first to have a lucky accident, mixing lime with fine volcanic ash. Ash can be thought of as naturally calcined rock, leaving silicon in a chemically active state like the calcium in calcined limestone. When this lime-ash mixture is slaked, a completely new substance is formed: calcium silicate hydrate or what cement chemists call C-S-H (approximately SiCa2O4 · xH2O).

C-S-H is still a mysterious substance today, but we know it is an amorphous gel without any set crystalline structure. It hardens fast, even in water. In addition, it is more durable than lime cement.

The ancient Greeks put this new cement to use in new and valuable ways, building concrete cisterns that survive to this day. But Roman engineers mastered the technology and constructed seaports, aqueducts and temples of concrete as well. Some of these structures are as good as ever today, two thousand years later. However, the formula for Roman cement was lost with the fall of the Roman Empire.

Modern Hydraulic Cement

While lime cement continued in use throughout the Dark and Middle Ages, true hydraulic cement was not rediscovered until the late 1700s. English and French experimenters learned that a calcined mixture of limestone and claystone could be made into hydraulic cement. One English version was dubbed “Portland cement” for its resemblance to the white limestone of the Isle of Portland, and the name soon extended to all cement made by this process.

Shortly thereafter, American makers found clay-bearing limestone’s that yielded excellent hydraulic cement with little or no processing. This cheap natural cement made up the bulk of American concrete for most of the 1800s, and most of it came from the town of Rosendale in southern New York.

Rosendale was practically a generic name for natural cement, although other manufacturers were in Pennsylvania, Indiana and Kentucky. Rosendale cement is in the Brooklyn Bridge, the U.S. Capitol building, most 19th-century military buildings, the base of the Statue of Liberty and many other places. With the rising need to maintain historic structures using historically appropriate materials, Rosendale natural cement is being revived.

True Portland cement slowly gained popularity in America as standards advanced and the pace of building quickened. Portland cement is more expensive, but it can be made anywhere the ingredients can be assembled instead of relying on a lucky rock formation. It also cures faster, an advantage when building skyscrapers a floor at a time. Today’s default cement is some version of Portland cement.

Modern Portland Cement

Today limestone and clay-containing rocks are sintered-roasted together at nearly melting temperature-at 1400° to 1500°C. The product is a lumpy mixture of stable compounds called clinker. Clinker contains iron (Fe) and aluminum (Al) as well as silicon and calcium, in four main compounds:

Alite (Ca3SiO5)
Belite (Ca2SiO4), known to geologists as larnite
Aluminate (Ca3Al2O6)
Ferrite (Ca2AlFeO5)

Clinker is ground to powder and mixed with a small amount of gypsum, which slows down the hardening process. And that is Portland cement.

Making Concrete

Cement is mixed with water, sand and gravel to make concrete. Pure cement is useless because it shrinks and cracks; it is also much more expensive than sand and gravel. As the mixture cures, four main substances are produced:

C-S-H
Portlandite
Ettringite (Ca6Al2(SO4)3(OH)12 26H2O; includes some Fe)
Monosulfate ([Ca2(Al,Fe)(OH)6] (SO4,OH,etc) xH2O)

The details of all this are an intricate specialty, making concrete as sophisticated a technology as anything in your computer. Yet basic concrete mix is practically stupid proof, simple enough for you and me to use. You see though we are smarter than that, we will not go around messing with cement and concrete mixes, because we know we should leave that to the professionals. So if you need a professional, check out repairfinders.com where they have only the best in the business, and you will never be let down. Jack is over and out.