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Chapter 1 Introduction

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More than 3/4's of the earth's surface is covered by water. Most of that is in the oceans. Less than 1 percent is 'fresh'. And most of that is in lakes. According to WORLD BOOK, the Earth consists of 71 percent water. However, US researchers have determined that the global population growth will outpace fresh water supplies in the next 40 years unless farming, industrial and household consumption patterns change. Water is life. More than 70 % of the human body consists of water. It takes less than a 1 % deficiency to make us thirsty. A 5 % deficit causes a slight fever. An 8 % shortage causes the glands to stop producing saliva and the skin turns blue. A person cannot walk with a 10 % deficit. 12 % brings death.

The problem is that only 2.5 percent of the Earth's water is fresh water. The rest of the Earth's supply is all salt water. In addition, 77 percent of that fresh water is locked up in ice caps and glaciers (an ice sheet covers all but 2.4 per cent of Antarctica's 14 million square kilometers. This ice contains 70 percent of all the world's fresh water). In the Soviet Union, a single body of water, Lake Baikal in Siberia, contains about the same volume of fresh water as the entire Great Lakes system. Together, the Great Lakes and Lake Baikal contain 40% of the world's presently available fresh water. This means that less than one percent (23 % of 2.5 %, or so) of all of the Earth's water is fresh water located in aquifers, rivers, soil, lakes, swamps, plant life and the atmosphere. Furthermore, not all of this fresh water is easily accessible. In areas where there is an abundance of water, like in the Amazon River basin or the far north tundra, there are few people. In areas with a pleasant environment for human habitation, water is not necessarily abundant.

The possibilities of capturing more of the Earth's fresh water are also limited. According to the researchers made up of Stanford University biologists, about 26 percent of the water available through rain is already captured, and there is not much more land available for rain-fed farming and grazing. Just over half the water from runoff, in lakes and streams, is already captured. We could increase this by 10 percent in 30 years if we built more dams. However, the global population is forecast to grow 45 percent during that same period. In south Georgia, water is mined from the Floridan, Clairborne, Clayton and Cretaceous aquifer system. The State of Georgia has restricted The City of Albany from withdrawing more than 2 Billion gallons per year from the Clayton aquifer. Water negotiators in Georgia, Florida and Alabama are working on a compact (Jan 1999) which might limit, allocate or restrict this finite resource in Southwest Georgia. The earth is a closed system? That meant that there is the same amount of water here today as there was 3 billion years ago? I find that to be questionable. There seems to be an equally plausible argument that meteors may be a substantial contributor to the earth's water supply.

May 18, 2001 -- Last year comet C/1999 S4 (better known as "Comet LINEAR") surprised
astronomers by breaking apart as it passed near the Sun. Now the long-dead comet has
surprised them again: New research shows Comet LINEAR was likely made up of water with
the same isotopic composition as water found here on Earth. The finding supports a
controversial idea that cometary impacts billions of years ago could have provided most of
the water in Earth's oceans.

However, the truth may be useless, because 30 years occurs sooner than 1 Million years! We Must ACT NOW or die sooner.

Because new water supplies are a luxury few can afford, or even physically have as an option, the coming trend will be increased emphasis on conservation and protection of existing water supplies. We can expect to see more legislation and regulation to protect water quality and to promote conservation. With the discovery of more and more contaminants infiltrating our underground supplies, ground water protection will continue to receive high priority. Water supply, wastewater disposal and management and control of storm water has been a pressing and legitimate concern of mankind since the dawn of civilization because pollution affects the very water we need for life. We have traditionally depended on an easily available supply of water in determining where settlements were established. Great cities generally grew next to rivers and lakes. During the early years of our development, getting rid of waste water was obviously a matter of concern but it was most easily dealt with by just dumping it downstream from where we drew our drinking water. Many communities just didn't worry about what they were doing to the water supply of people further downstream. That, however, has changed. Today, most of the water people use is reused over and over and over: RECYCLED.

Water treatment and wastewater treatment processes can only be managed effectively when the operator knows what is happening at every step of treatment. Since direct communication with microscopic organisms is not yet feasible, man has figured out some ways of getting the information that will provide enough data for analysis to adjust the process. These ways have been formalized into Laboratory Procedures. Standardized testing procedures will reduce the amount of error (noise) we humans inject. Sampling activities and laboratory tests must be carefully, thoughtfully and uncompromisingly faithfully performed in order to prevent lying to ourselves about what is happening in a treatment system. Reliable data can be captured when the noise level interferes only minimally. Proving the argument by selecting only the supporting facts will cause big upsets in the process.

Waste is a major problem facing humanity. The average American expects copious food, readily available manufactured goods and abundant energy. Waste is an inescapable side product of our modern industrialized society, arising from both the manufacturing processes and the domestic use of the fruit of our labors. Incorrect management of these wastes result in pollution of the air, water, and land with detrimental effects to both our lives and environment. Waste management and pollution prevention are such immense problems in the United Sates that our federal government has enacted laws regulating these areas. Some of the relevant laws include the Clean Water Act, the Clean Air Act, the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation and Liability Act. The Environmental Protection Agency was created to administer these and other acts of Congress.

Anything in water that is not H₂O is a contaminant or impurity. All water is suspect, and it is the principal job of the water chemist to expose any impurities, set specifications for each impurity acceptable for the intended used of the water after treatment, and devise economical treatment methods to reach those quality limits. It is important to recognize that the terms impurity, contamination or pollution are subjective ones. One would probably not think of dissolved oxygen in water as being a contaminant, or an impurity, especially in natural waters. Pure, deionized water is unpleasant to taste and is toxic (in quantity). A contaminant is considered a pollutant when its concentration reaches a level that may be considered harmful either to aquatic life or to the public health if the water is for potable purposes. Water is an essential requirement for all life forms. Plants and animals utilize water for growth and development. Degrading water quality creates drastic effects on the dependent organisms, including man. Wastewater is defined as water that contains substances which are detrimental to water quality. Wastewater is water that contains substances, which are undesirable in the immediate use of the stream. These substances can be natural or man made and are usually referred to by source of the waste, either industrial or domestic. Domestic waste consists of human fecal matter, household cleaners, laundry and bath residue and excess food wastes, along with the occasional tennis ball, diaper, and sanitary napkin. Graywater usually refers to laundry and bath water, while blackwater means the toilet or septic system wastewater. Industrial waste is the byproduct of manufacturing processes and may consist of a large variety of substances from sources as diverse as: paper mills, slaughterhouses, metal foundries, bakeries, textile plants, breweries, and mineral mines. In addition to these point sources of wastewater, there is concern for the non-point sources of pollutants such as produced by rain water run-off from parking lots, farms, and landfills. Storm water is often collected in storm sewers, which connect, to the sanitary sewer system. Water with all these extras affect growth and development in ways undesirable, so removing the undesirables is desirable: Clean Water. A better description

The Clean Water Act addresses the establishment and upgrading of Publicly Owned Treatment Works (POTW), through federal grants and loans, to minimize the polluting effect of dumping municipal domestic and industrial wastewater into the surface waters of our land. This need arises from the centuries old solution to the domestic waste problem in cities: collecting the liquid and semisolid wastes in underground sewer systems and flushing it to the nearest river, stream, lake or ocean inlet. Russia solved this problem, the story goes, by requiring all wastewater to be discharged UPSTREAM of the intake of their drinking water system. Domestic wastes, for the most part, are highly nutritive to microorganisms and plants and have been used for thousands of years in small amounts as fertilizer for farms. However, the influx of huge amounts of fertilizing material in confined water bodies results in an initial explosive growth rate, which quickly depletes all the available oxygen in the water. Without oxygen the animals and plants suffocate, die and then putrefy. This process is called eutrophication. Continued dumping of raw domestic sewage into the water renders it unusable for any purpose. Industrial wastewater, in many instances, is toxic to all organisms in the water and simply ruins it for everyone.

The modern POTW is the culmination of decades of technological development in the treatment of wastewater. The initial treatment goal of reducing disease-causing organisms and protecting human health has been expanded to maintaining or improving the water quality of the receiving stream to support a normal flora and fauna population in addition to being suitable for domestic and recreational purposes. Wastewater is conveyed from the household or industry to the POTW through the sanitary sewer system. Undesirable substances in the wastewater are removed through a combination of physical, biological and chemical processes. These processes are combined in a variety of designs to provide Preliminary, Primary, Secondary and Tertiary treatment of the water. Preliminary treatment is designed to remove solid materials from the wastewater that can adversely affect the plant processes and equipment. Materials such as lumber, cardboard, rags, plastic, cans, sand and gravel can plug lines and damage pumps and other mechanical devices. Physical processes common to Preliminary treatment are filtration and sedimentation and are provided by bar racks, screens, shredders and grit chambers. Primary treatment is designed to capture settleable and floatable solids that pass Preliminary treatment.

After removing the big stuff, Primary Treatment targets smaller stuff. This physical removal is accomplished in tanks called clarifiers. The velocity of the wastewater is reduced to a minimum to allow solids to float to the top of the tank or to settle to the bottom. Allow gravity to work on the densities to sort materials from the water. Primary treatment facilities may remove as much as 60% of the influent suspended solids and 30% of the biochemical oxygen demand (BOD). These separated solids are called primary sludge and are then treated in a separate set of additional processes known as solids handling.

Secondary treatment is designed to cleanse the wastewater further by reducing the concentrations of dissolved and colloidal organic matter. Now we are getting down to the smaller-still stuff. These are not removed to any appreciable degree during the physical processing of the wastewater in the Preliminary and Primary steps. The activated sludge process of Secondary treatment uses microorganisms to feed on the waste materials to achieve a biological conversion of the waste. Some microorganisms are encouraged to feed and multiply on the waste by introducing large quantities of air to the mixture while other types of bacteria assimilate or convert the material in the absence of free oxygen. The aeration basin is designed to ensure large amounts of dissolved oxygen for respiration to the microorganisms, constant mixing of the contents of the basin to prevent layering, and adequate air flow to purge the gaseous metabolic byproducts of the microorganisms from the basin.

After a suitable residence time in the aeration basin, the wastewater is passed to a secondary clarifier where the heavier, well-fed microorganisms settle to the bottom of the tank forming activated sludge. The activated sludge is either recycled to the aeration basin or pumped to solids handling for disposal (wasted). The return activated sludge is mixed with the influent wastewater to the aeration basin to assure a continuing supply of adapted microorganisms for satisfactory biological treatment. The clarified supernatant water can be disinfected, most frequently by chlorination, and discharged to a receiving stream if it is of sufficient purity, otherwise it is passed to a Tertiary unit for further treatment. The solids that are removed in the primary and secondary clarifiers are largely composed of highly putrescible organic materials. The three goals of solids handling are: 1) decrease the volume of the sludge to be handled; 2) stabilize the organic material so that it is suitable for land disposal, incineration, or composting; and 3) generate and capture methane for use as a fuel. Biogas. The sludge is processed in units called anaerobic digesters. Acid producing and gas producing bacteria are allowed to digest the sludge in the absence of oxygen to achieve a reduction in the volume of the sludge, stabilize the sludge and produce carbon dioxide and methane as major byproducts. The digested sludge can then be dewatered using belt presses, centrifuges, drying beds, or vacuum filters prior to final disposal by incineration, land filling or composting.

Tertiary Treatment is any treatment process that upgrades wastewater to meet specific reuse requirements. Nutrient removal is becoming more common. Typical processes include chemical treatment and pressure filtration. Advanced waste treatment is another name often used in discussions about processes cleaning water insufficiently treated by conventional means.

The primary function of a wastewater laboratory is to provide analytical data. This data is used to monitor the effectiveness of the treatment process in the plant. All wastewater treatment plants are operated along guidelines established by our federal and state governments. The purpose of these guidelines is to protect human health and the environment by regulating the quantity and cleanliness of the wastewater effluent from facilities, which may be discharged to receiving streams. Making observations is fundamental to all science. A quantitative observation or measurement, always consists of two parts: a number and a scale (called a unit, an engineering unit), Both parts must be present for the measurement to be meaningful. Numbers by themselves mean nothing, one foot per second is a lot different than one mile per second.

Chemical laboratory work frequently requires measurement of the volumes of solutions or of pure liquids. It is very important to realize that a measurement always has some degree of uncertainty. The uncertainty of a measurement depends on the precision of the measuring device. Two terms often used to describe uncertainty in measurements are precision and accuracy. Accuracy refers to the agreement of a particular value with the true value. Precision refers to the degree of agreement among several measurements of the same quantity. Precision reflects the reproducibility of a given type of measurement. Two more terms describe different types of errors: random and systematic. Random describes equal chances of error being high or low; conversely, systematic errors occur in the same direction each time; either always high or always low. The point is that high precision is an indication of accuracy only if you can rule out systematic errors. If an average result is close enough to the true or accepted value, the test is said to be unbiased.

The calculation, standard deviation [Formulas] of repeated analyses of the same sample, is another way of discussing the precision of the accuracy. Only if a procedure is unbiased AND precise can it be said that the test is being done accurately. Laboratory analysis could be said to be nothing more than methods of extending man's senses. Sight, smell, taste, hearing and touching provides information input to the biological computer called the brain. We have learned to extend those five senses toward the infinite and the infinitesimal. Instruments allow us to discriminate and quantify particular molecules through pseudo sight. Other devices extend our senses in many ways.

This 'manual' can only begin to provide the information an analyst will need and use in the performance of this sophisticated work. Math, physics, chemistry, and English are disciplines an analyst needs to be familiar with in addition to the subjects covered in this manual. Many good textbooks covering math, chemistry, physics and English in much better detail are available and are recommended to be stocked in the Laboratory Library. A chemistry textbook is one that an analyst should study daily. Collateral reading is a very effective studying technique. Generally, a book is written by one person (like one teacher). Some are likable, some not. Some explain well one subject, others explain others. Books are the first kind of expert systems . This one manual, however the quality and coverage, can only begin to provide the information some will need, some of the time. Continuing education in this field, or any field, is a must.

Questions for Chapter 1
1. Describe five differences between aerobic and anaerobic digesters.
2. List five components of domestic waste.
3. List five different types of industrial waste.
4. What is a POTW?
5. What Act of Congress covers wastewater treatment and disposal?
6.

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