water quality and system

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These devices are "listed" and it is often specified in contracts that only listed items are allowed in the construction. If construction is required to be subject to the code, and most new construction is subject to the codes, then the codes themselves require the materials be "listed."

Other Code-Making Bodies

Just as there are associations for the fire, building and plumbing codes, many other associations and trade groups provide input to codes. Professional organizations continue to develop standards for cost effective and safe systems. Some of these professional associations are the American Society of Civil Engineers, the National Sanitation Foundation, The American Society of Mechanical Engineers and the Plastic Pipe and Fittings Association (see Chapter 16).

Water Rights

Just as there are laws regulating pollution, water purity and pluming and piping, water is property and there are rights to use water as well as rules against pollution. In many states, legal title to water is the same as legal rights to coal or gold.

The two main types of water rights are adjudicated rights and riparian rights.

Adjudicated Rights

In the Western United States, which is mostly arid desert, water rights are governed by adjudicated rights. In the days of early western settlement, a farmer or rancher quickly found there was not enough natural rainfall to keep the crops alive until harvest. The crops would sprout and take root in the spring, but with the approach of warm summer days the crops would wither and die before harvest. To keep the crops growing, the farmer irrigated the fields by channeling water from a stream or river onto the fields. The channeled flows would sometimes keep the crops alive until the harvest could be gathered in the fall.

As more farmers moved onto the land, however, ditches were cut into the river upstream from the original farmer. When the original farmer wondered where the water in the river had gone, he went upstream only to find another farmer had diverted the stream and was using the water instead. The farmer faced with certain starvation if he did not get the water onto his own crops would destroy

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the upstream farmer's irrigation system. Since the upstream farmer was faced with a similar situation, both farmers were forced to settle the issue in the Old West fashion ... with six-guns. Since this method of settling arguments was not good for the local community, the concept of an adjudication of the water was born.

In an adjudicated right, the first farmer to put water to beneficial use is allotted a portion of the water. Thus the first right became his. The next farmer receives the next portion and so on down the river until all the water in the river is accounted for. Today, each owner is allotted so many gallons based upon complex formulas of water application. The state agency responsible for administering these rights is tasked with making sure that each farmer or owner receives his share from the total allocation.

Under this concept, the rights to the water were combined with the rights to the land. Later, when large canals and complex water transportation systems made moving the water more feasible, the water was transferred separately from the land. For example, the land could be sold, but the water rights retained, or the water rights sold and the land retained. Many a western water swindle occurred when a potential landowner was shown land adjacent to the river with a large canal right next to his property, only to discover that his newly purchased land rights did not include the water rights. Later, this type of dishonesty declined when local banks began to make loans for land deals.

Riparian Rights

Contrary to adjudicated water property rights common in the arid western states, riparian rights, common to eastern states, are conveyed to landowners adjacent to rivers lakes and streams. The basis for riparian rights is that there is essentially enough water available for everybody and the adjacent owner to the river or lake may take water freely from the adjacent water body as long as significant changes to flows or levels do not affect others.

Consumptive and Non-Consumptive Use

There are two types of use patterns discussed in the management of water rights. These are consumptive use and non-consumptive use. For most facilities, use is of the non-consumptive type. The water comes into the facility and is used for washing, flushing, rinsing, etc. and then it is returned.

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When returned, it is more polluted, but essentially the same volume is returned.

Consumptive use means that the facility owner consumes the water on his property. Mostly consumptive use occurs in power plants where it is used for cooling and it is evaporated into the air as it cools the power turbines or other equipment.

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Chapter 8

Water Purity

People are getting sick in the facility, and the cause is traced to the water. Lost productivity and a lawsuit ensues. Then the building owner has to tell the public. How could this have been prevented? The only way to know if water is safe is to have it tested regularly. Understanding the dangers of impurities in water, including the various types of problems that occur, is essential to properly overseeing water testing and purification.

The Roots of Water Purity

People talk about pure water and wonder if their water is absolutely safe. In fact, no water is completely pure and the term "absolutely safe" depends upon so many variables that industry professionals qualify the term with relative factors that will be discussed here. A quick look at Figure 8-1 and a short discussion of water chemistry will help clarify this issue. The figure shows a sketch of the water molecule which is made up from two atoms of hydrogen bonded to one atom of oxygen.

The oxygen atom has eight protons (positive charge) and six electrons (negative). It is the imbalance of the electrical charges that causes oxygen to want to bond, which is why pure oxygen is such a reactive gasit is a key element of fire, for example.

The hydrogen atom has one proton and one electron. The electron on the hydrogen atom electrically bonds in the two free positions in the oxygen atom and forms a water molecule.

It can be seen from the figure that one side of the molecule has

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Figure 8-1.

The water molecule.

negative attractions and the other side has positive attractions. Because of the shape of the molecules, other chemicals dissolve in the water. This is why it is difficult to have water that is absolutely pure. Dirt or soil will soften and dissolve in the water along with salts, acids and many other components.

The ability of water to dissolve many chemicals accounts for ionized particles in water that could be called impurities. These particles include mineral salts, metals, chlorides, acids and others.

As a result, the purity or "safety" of water is relative. The only way to know if the water is safe is to have it tested. A complete battery of tests can cost as much as $3,000. Depending upon the size of the facility, several samples may be required from different areas at different times of the year or season. Basic tests are less expensive and can be performed for as little as $200.

Completely pure water is "hungry" and wants to bond with other minerals. Extremely pure water is difficult to attain and even harder to maintain because of the aggressive nature of the molecules. In general, however, this desire of water to bond with other minerals is what makes it such a valuable substance since cleaning, washing and all life depends upon these chemical bonds.

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As with all molecular chemistry, a molecule has different characteristics from its constituent elements. Oxygen is a reactive gas, as is hydrogen. When they react together, the hydrogen burns in the oxygen, releasing a lot of heat that results from molecular bonding. The result of the reaction is water, but the heat from the reaction is so strong that the water forms steam. If the reaction is very carefully controlled, the water from the reaction can be captured.

Water Impurities

Impurities in water are relative. For example, impurities in a wastewater may be a chemical that poisons the bacteria that will purify the water over time (see Chapter 9, where we discuss water purification techniques). In drinking water, impurities can make people ill; other impurities give the water flavor. For a few types of water supplies, the absence of mineral impurities will cause the water to have a bland taste. In other water, the presence of mineral salts are thought to enhance health.

Water impurities can take one of two basic formseither the impure particles are suspended in the water, or the elements of the impurities have separated from their basic form and have dissolved in the water. Suspended particles can be removed by filtration. A dissolved impurity is more difficult and costly to remove than a suspended impurity. Figure 8-2 shows some relative impurities in water and the sizes of the impurities. Impurities can be living microorganisms or they can be mineral or organic chemicals.

Examples of impurities in drinking water include turbidity, dissolved salts, dissolved metals, microorganisms, living organisms, radionuclides, volatile organic compounds and pesticides. Nationwide, a committee tracks and reviews current and pending regulations concerning drinking water supplies. The document, called Drinking Water Standards, is available from the Office of Water 4601, U.S. EPA, Washington, DC 20460, (800) 426-4791.

In addition, HDR Engineering Co. of Omaha, NE provides a synopsis of the information in a poster format that is updated on a continuous basis. The poster, called UPDATE, can be obtained from HDR by calling (402) 399-1450.

The advantage of the poster over the EPA standards is the poster is updated more often and it includes all of the proposed regulations as well as the posted standards. Using the poster makes it easier for the facility manager to keep informed on the issues being debated by the water industry.

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Figure 8-2.

Typical water impurities and selected separation processes. Reprinted from Journal, by permission, ©1995, American Water Works Association.

Action Level of Contaminants

Each impurity has a recommended standard. It is important that the facility manager understand the basis for level set by the regulations. The U.S. EPA has set the action level well below the amount where there are known ill health effects. The purpose is to require facility managers to notify occupants of an impurity in the water supply in time for the public to take action.

While a normal person's health will not be at risk if the standard is exceeded, there is the potential that elderly, infirm, children or individuals with contributing diseases may experience a degree of increased health risk.

Turbidity

A common, easily recognized water impurity is turbidity. Turbidity is the presence of free suspended particles in a water supply. Because of their small size, the particles will not readily settle out, but given enough time, these particles settle to the bottom of the basin. The particles obscure light from shining through the water. In water analysis, turbidity is used to signal the presence of other chemicals or plant life that might have potential ill health effects.

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Hence, the general application: If water is not clear, do not use it.

Turbidity can simply be an inorganic particle of very small size that is evenly dispersed in the water causing a cloudy appearance that poses no ill health effects. Turbidity is measured in National Turbidity Units (NTU). An exact reading is obtained from a laboratory, but many labs will make a color sheet available. By comparing a sample of water from a specific source to the color sheet, an estimate of the turbidity can be made. By itself, turbidity in drinking water can be insignificant, provided the source of the turbidity is known. For example, a fine clay, evenly distributed in well water, can be completely inert and have no effect on the user. Since turbidity can block a lab analysis for other chemicals and microorganisms, however, it is regulated in water supplies.

Turbidity can include both inorganic and organic particles, but it does not include dissolved salts, which will not settle out and must be removed by an alternate technology.

Dissolved Salts

As previously discussed, common dissolved salts in water include sodium chloride, sodium bicarbonate, calcium carbonate, calcium sulfite, magnesium carbonate, magnesium chloride and other salts derived from magnesium, calcium, potassium or sodium.

Water Hardness - Throughout the country, water supplies derived from wells contain dissolved mineral salts. These salts from either calcium or magnesium are combined with a carbonate ion in the forms, CaCO3 or MgCO3.

Salts leave a film residue when evaporated and either calcium or magnesium remain on the sides of pots, pans and bathtubs when water evaporates. The white film is a salt called calcite which is actually calcium carbonate. Calcite when left as residue on the side of a vessel is hard to dissolve. Calcite, by the way, is the same mineral that makes stalactites and stalagmites found in caves. Because the presence of these salts make it difficult for soap to form a lather, the water is called hard water.

Both calcium carbonate and magnesium carbonate will dissolve in a slightly acidic compound such as citric or muriatic acid. The hardness component of water is measured with a test kit that measures the amount of calcium carbonate dissolved in water.

The calcium ions can be measured in unit weight per gallon and are usually referred to in grains or grains per gallon. (One grain per gallon is equal to 17.12 parts per million.) A complete chemistry

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analysis will indicate hardness or the presence of both the calcium and magnesium ions.

Water with less than 100 ppm of calcium or sodium is considered soft water. Water in excess of 220 ppm is considered hard water. Most hard waters come from wells in the midwest region. Water supplies that are primarily derived from surface water are not as hard as well water.

The use of grains per gallon (gpg) is used in sizing water softeners which remove calcium and magnesium ions. The relationship of the number of grains of hardness and the amount of water to be softened is used by water softener manufacturers to calculate the amount of water softener resin needed (see Chapter 10).

Hard water has no ill health effects up to 300-400 mg/liter concentrations.

Other Salts - Sodium chloride, or table salt, is sometimes present in water supplies but does not show up as hardness in a water hardness test. Too much sodium has the potential to affect individuals with cardiovascular disease; however, most sodium received by individuals is in the form of table salt added to foods rather

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than sodium dissolved in a drinking water supply.

Sulfates and sulfites in water supplies will give water an unpleasant odor. High concentrations of sulfates can create stomach upsets and will have a laxative effect on the lower bowel. Table 8-1 lists some common salts found in water supplies.

Dissolved Metals

In drinking water supplies, the presence of dissolved metals potentially poses a problem to the facility manager. Of the most significance are lead and copper. In general, these metals do not normally dissolve in water supplies unless the water carries a slightly acidic component whereby lead or copper from the pipe materials dissolves in the water.

Copper - Copper enters water piping through acidic decomposition of the water piping. In rare other cases, it can be present in well water supply or in surface water supplies from copper bearing minerals. Copper in small concentrations can pose ill health effects in the form of stomach or bowel discomfort but effects are not permanent.

Table 8-2. Definitions of salt concentrations.

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