About Water Treatment

8/9/2019 About Water Treatment

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1. Introduction

1.1 water pollution categories

1.2 causes of water pollution

2. Biological waste treatment.

3. Water treatment

3.1 Pre-treatment

3.2 Secondary treatment

3.2.1 Surface-aerated basins.

3.2.2 Rotating biological contactors.

3.3 Tertiary treatment

3.3.1 Filtration.

3.3.2 Lagooning.

3.3.3 Constructed wetlands.

3.3.4 Nutrient removal.

3.3.5 Nitrogen removal.

3.3.6 Phosphorus removal.

3.3.7 Disinfection.

3.3.8 Odour removal.

3.3.9 Package plants and batch reactors.

4. Sewage treatment.


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5. Parameters of agricultural significance.

5.1 Total salt concentration.

5.2 Electrical conductivity

5.3 Sodium adsorption ratio.

5.4 Toxic ions.

5.5 Trace elements and heavy metals.

5.6 pH.

6. Types of Radioactive wastes

6.1 Low-level radioactive wastes.

6.2 Intermediate-level radioactive wastes.

6.3 High-level radioactive wastes.

6.4 Naturally occurring radioactive materials.

6.5 Transuranic wastes.

6.6 Wastes from the nuclear fuel cycle.


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Water pollution is any contamination of water with chemicals or other foreign substances that are

detrimental to human, plant, or animal health. These pollutants include fertilizers and pesticidesfrom agricultural runoff; sewage and food processing waste; lead, mercury, and other heavy

metals; chemical wastes from industrial discharges; and chemical contamination from hazardous

waste sites. Worldwide, nearly 2 billion people drink contaminated water that could be harmful to

their health.

Water pollution affects plants and organisms living in these bodies of water; and, in almost all

cases the effect is damaging either to individual species and populations, but also to the natural

biological communities.

Water pollution occurs when pollutants are discharged directly or indirectly into water bodies

without adequate treatment to remove harmful compounds.

1.1 Water pollution categoriesSurface water and groundwater have often been studied and managed as separate

resources, although they are interrelated. Sources of surface water pollution are generally grouped

into two categories based on their origin.

Point source pollution

Non-point source pollution

Groundwater pollution

1.2 Causes of water pollutionMost water pollution doesn't begin in the water itself. Take the oceans: around 80 percent of ocean

pollution enters our seas from the land. Virtually any human activity can have an effect on the quality of ourwater environment. When farmers fertilize the fields, the chemicals they use are gradually washed by rain

into the groundwater or surface waters nearby. Sometimes the causes of water pollution are quite

surprising. Chemicals released by smokestacks (chimneys) can enter the atmosphere and then fall back to

earth as rain, entering seas, rivers, and lakes and causing water pollution. Water pollution has many

different causes and this is one of the reasons why it is such a difficult problem to solve.


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Biological wastewater treatment processes are primarily designed for the removal of dissolved and

suspended organic matter from wastewaters. The environmental conditions are optimised to encourage

growth of the micro-organisms which use the organic compounds as substrate.

Biological wastewater treatment is also capable of removing other wastewater components, including

suspended solids, nitrogen, phosphorus, heavy metals and xenobiotics.

In general the biological wastewater treatment is the most efficient and economic way of removing organic

pollution from a wastewater.

Water treatment describes those processes used to make watermore acceptable for a desired end-use.

These can include use as drinking water, industrial processes, medical and many other uses. The goal of

all water treatment process is to remove existing contaminants in the water, or reduce the concentration of

such contaminants so the water becomes fit for its desired end-use. One such use is returning water that

has been used back into the natural environment without adverse ecological impact.

The processes involved in treating water for drinking purpose may be solids separation using physical such

as settling and filtration, chemical such as disinfection and coagulation.

Biological processes are also employed in the treatment of wastewater and these processes may include,

for example, aerated lagoons, activated sludge orslow sand filters.

3.1 Pre-treatment Screening

Grit removal

Primary treatment
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In the primary sedimentation stage, sewage flows through large tanks, commonly called "primary

clarifiers" or "primary sedimentation tanks". The tanks are large enough that sludge can settle and floating

material such as grease and oils can rise to the surface and be skimmed off.

3.2Secondary treatmentSecondary treatment is designed

to substantially degrade the

biological content of the sewage

which is derived from human waste,

food waste, soaps and detergent.

The majority of municipal plants

treat the settled sewage liquor using

aerobic biological processes.

3.3 Surface-aerated basinsThe principles of the design and operation of

surface-aerated systems for biological treatment

of industrial waste waters are discussed and

results are presented from an investigation on the

performance of such systems, based on a

literature survey and postal questionaires, and

analysis of the collected data to obtain

correlations useful in the design of surface-

aerated basins. The rate of removal of 5 day BOD

is a linear function of the influent BOD, the rate coefficient depending on the nature of the waste water and

the temperature. Examples are given for various waste waters, including those from oil refineries and pulpmills, and recommendations are made regarding the optimal horse-power for the aerators (which should be

divided between multiple units no more than 100 -125 ft apart), volume and depth of the basin, and

detention period (for a given detention period, single basins or basins in parallel will remove more BOD

than basins in series).
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3.4 Rotating biologicalcontactorsA rotating biological contactoror

RBC is a biological treatment

process used in the treatment of

wastewaterfollowing primary

treatment. The primary treatment

process removes the grit and other

solids through a screening process

followed by a period of settlement.

The RBC process involves allowing the wastewater to come in contact with a biological medium in order to

remove pollutants in the wastewater before discharge of the treated wastewater to the environment, usually

a body of water (river, lake or ocean). A rotating biological contactor is a type of secondary treatment

process. It consists of a series of closely spaced, parallel discs mounted on a rotating shaft which is

supported just above the surface of the waste water. Microorganisms grow on the surface of the discs

where biological degradation of the wastewater pollutants takes place.

3.5 Tertiary treatmentThe purpose of tertiary treatment is to provide a final treatment stage to raise the effluent quality before it is

discharged to the receiving environment (sea, river, lake, ground, etc.). More than one tertiary treatment

process may be used at any treatment plant. If disinfection is practiced, it is always the final process. It is

also called "effluent polishing".

3.5.1 Filtration

Sand filtration removes much of the residual suspended matter. Filtration overactivated carbon removes

residual toxins.
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3.5.2 Lagooning

Lagooning provides settlement and further biological improvement through storage in large man-made

ponds or lagoons. These lagoons are highly aerobic and colonization by native macrophytes, especially

reeds, is often encouraged. Small filter feeding invertebrates such as Daphnia and species ofRotiferagreatly assist in treatment by removing fine particulates.

3.5.3 Constructed wetlandsConstruucted wetlands include engineered reedbeds and a range of similar methodologies, all of which

provide a high degree of aerobic biological improvement and can often be used instead of secondary

treatment for small communities, also see phytoremediation. One example is a small reedbed used to clean

the drainage from the elephants' enclosure at Chester Zoo in England.

3.5.4 NutrientremovalWastewater may contain high levels of the nutrients nitrogen and phosphorus. Excessive release to the

environment can lead to a build up of nutrients, called eutrophication, which can in turn encourage the

overgrowth of weeds, algae, and cyanobacteria (blue-green algae). This may cause an algal bloom, a rapid

growth in the population of algae. The algae numbers are unsustainable and eventually most of them die.

The decomposition of the algae by bacteria uses up so much of oxygen in the water that most or all of the

animals die, which creates more organic matter for the bacteria to decompose. In addition to causing

deoxygenation, some algal species produce toxins that contaminate drinking watersupplies. Different

treatment processes are required to remove nitrogen and phosphorus.

3.5.5 Nitrogen removal

The removal of nitrogen is effected through the biological oxidation of nitrogen from ammonia (nitrification)

to nitrate, followed by denitrification, the reduction of nitrate to nitrogen gas. Nitrogen gas is released to the

atmosphere and thus removed from the water.
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3.5.6 Phosphorus removal

Phosphorus removal is important as it is a limiting nutrient for algae growth in many fresh water systems

(for negative effects of algae see Nutrient removal). It is also particularly important for water reuse systems

where high phosphorus concentrations may lead to fouling of downstream equipment such as reverseosmosis.

3.5.7 Disinfection

The purpose ofdisinfection in the treatment of wastewater is to substantially reduce the number of

microorganisms in the water to be discharged back into the environment. The effectiveness of disinfection

depends on the quality of the water being treated (e.g., cloudiness, pH, etc.), the type of disinfection being

used, the disinfectant dosage (concentration and time), and other environmental variables. Cloudy waterwill be treated less successfully since solid matter can shield organisms, especially from ultraviolet light or if

contact times are low. Generally, short contact times, low doses and high flows all militate against effective

disinfection. Common methods of disinfection include ozone, chlorine, ultraviolet light, or sodium

hypochlorite. Chloramine, which is used for drinking water, is not used in wastewater treatment because of

its persistence.

3.5.8 Odour removal

Early stages of processing will tend to produce smelly gasses, hydrogen sulfide being most common in

generating complaints from nearby areas. Large process plants in urban areas will often contain a foul air

removal tower, composed of air circulators, a contact media with bio-slimes, and circulating fluids to

biologically capture and metabolize the obnoxious gasses previously contained by reactor enclosures.

3.5.9 Package plants and batch reactors

In order to use less space, treat difficult waste, deal with intermittent flow or achieve higher environmental

standards, a number of designs of hybrid treatment plants have been produced. Such plants often combine

all or at least two stages of the three main treatment stages into one combined stage. In the UK, where a

large number of sewage treatment plants serve small populations, package plants are a viable alternative

to building discrete structures for each process stage.
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4 SewageSewage treatment, or domestic wastewater treatment, is

the process of removing contaminants from wastewater

and household sewage, both runoff (effluents) and

domestic. It includes physical, chemical, and biological

processes to remove physical, chemical and biological

contaminants. Its objective is to produce a waste stream

(or treated effluent) and a solid waste or sludge suitable

for discharge or reuse back into the environment. This

material is often inadvertently contaminated with many toxic organic and inorganic compounds.

With over 8 billion people on the planet, disposing of sewage waste is a major problem. In developing

countries, many people still lack clean water and basic sanitation (hygienic toilet facilities). Sewage

disposal affects people's immediate environments and leads to water-related illnesses such as diarrhea

that kills 3-4 million children each year. (According to the World Health Organization, water-related

diseases could kill 135 million people by 2020.) In developed countries, most people have flush toilets that

take sewage waste quickly and hygienically away from their homes.

Yet the problem of sewage disposal does not end there. When you flush the toilet, the waste has to go

somewhere and, even after it leaves the sewage treatment works, there is still waste to dispose of.

Sometimes sewage waste is pumped untreated into the sea. Until the early 1990s, around 5 million tons of

sewage was dumped by barge from New York City each year. The population of Britain produces around

300 million gallons of sewage every day, some of it still pumped untreated into the sea through long pipes.

The New River that crosses the border from Mexico into California carries with it 20-25 million gallons (76-

95 million litres) of raw sewage each day.

In theory, sewage is a completely natural substance that should be broken down harmlessly in the

environment: 90 percent of sewage is water. In practice, sewage contains all kinds of other chemicals, from

the pharmaceutical drugs people take to the paper, plastic, and other wastes they flush down their toilets.

When people are sick with viruses, the sewage they produce carries those viruses into the environment. It

is possible to catch illnesses such as hepatitis, typhoid, and cholera from river and sea water.
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5 Parameters of agriculturalsignificance

The quality of irrigation water is of particular importance in arid zones where extremes of temperature and

low relative humidity result in high rates of evaporation, with consequent deposition of salt which tends to

accumulate in the soil profile. The physical and mechanical properties of the soil, such as dispersion of

particles, stability of aggregates, soil structure and permeability, are very sensitive to the type of

exchangeable ions present in irrigation water. Thus, when effluent use is being planned, several factors

related to soil properties must be taken into consideration. A thorough treatise on the subject prepared by

Ayers and Westcot is contained in the FAO Irrigation and Drainage Paper No 29 Rev. 1 (FAO 1985).

Another aspect of agricultural concern is the effect of dissolved solids (TDS) in the irrigation water on the

growth of plants. Dissolved salts increase the osmotic potential of soil water and an increase in osmotic

pressure of the soil solution increases the amount of energy which plants must expend to take up water

from the soil. As a result, respiration is increased and the growth and yield of most plants decline

progressively as osmotic pressure increases. Although most plants respond to salinity as a function of the

total osmotic potential of soil water, some plants are susceptible to specific ion toxicity.

Many of the ions which are harmless or even beneficial at relatively low concentrations may become toxicto plants at high concentration, either through direct interference with metabolic processes or through

indirect effects on other nutrients, which might be rendered inaccessible. Morishita (1985) has reported that

irrigation with nitrogen-enriched polluted water can supply a considerable excess of nutrient nitrogen to

growing rice plants and can result in a significant yield loss of rice through lodging, failure to ripen and

increased susceptibility to pests and diseases as a result of over-luxuriant growth. He further reported that

non-polluted soil, having around 0.4 and 0.5 ppm cadmium, may produce about 0.08 ppm Cd in brown rice,

while only a little increase up to 0.82, 1.25 or 2.1 ppm of soil Cd has the potential to produce heavily

polluted brown rice with 1.0 ppm Cd.

Important agricultural water quality parameters include a number of specific properties of water that are

relevant in relation to the yield and quality crops, maintenance of soil productivity and protection of the

environment. These parameters mainly consist of certain physical and chemical characteristics of the


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water. Table 7 presents a list of some of the important physical and chemical characteristics that are used

in the evaluation of agricultural water quality. The primary wastewater quality parameters of importance

from an agricultural viewpoint are:

Table 7: PARAMETERS USED IN THE EVALUATION OF AGRICULTURAL WATER QUALITY

Parameters Symbol Unit

Physical

Total dissolved solids TDS mg/l

Electrical conductivity Ecw dS/m1

Temperature T C

Colour/Turbidity NTU/JTU2

Hardness mg equiv. CaCO3/l

Sediments g/l

Chemical

Acidity/Basicity pH

Type and concentration of anions and cations:

Calcium Ca++ me/l3

Magnesium Mg++ me/l

Sodium Na+ me/l

Carbonate CO3-- me/l

Bicarbonate HCO3- me/l

Chloride Cl- me/l

Sulphate SO4--

me/lSodium adsorption ratio SAR

Boron B mg/l4

Trace metals mg/l

Heavy metals mg/l

Nitrate-Nitrogen NO3-N mg/l

Phosphate Phosphorus PO4-P mg/l

Potassium K mg/l

1 dS/m = deciSiemen/metre in SI Units (equivalent to 1 mmho/cm)

2 NTU/JTU = Nephelometric Turbidity Units/Jackson Turbidity Units

3 me/l = milliequivalent per litre

4 mg/l == milligrams per litre = parts per million (ppm); also,

mg/l ~ 640 x EC in dS/m

Source: Kandiah (1990a)


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5.1 Total Salt ConcentrationTotal salt concentration (for all practical purposes, the total dissolved solids) is one of the most important

agricultural water quality parameters. This is because the salinity of the soil water is related to, and often

determined by, the salinity of the irrigation water. Accordingly, plant growth, crop yield and quality of

produce are affected by the total dissolved salts in the irrigation water. Equally, the rate of accumulation of

salts in the soil, or soil salinization, is also directly affected by the salinity of the irrigation water. Total salt

concentration is expressed in milligrams per liter (mg/l) or parts per million (ppm).

5.2 Electrical ConductivityElectrical conductivity is widely used to indicate the total ionized constituents of water. It is

directly related to the sum of the cations (or anions), as determined chemically and is closelycorrelated, in general, with the total salt concentration. Electrical conductivity is a rapid and

reasonably precise determination and values are always expressed at a standard temperature

of 25C to enable comparison of readings taken under varying climatic conditions. It should be

noted that the electrical conductivity of solutions increases approximately 2 percent per C

increase in temperature. In this publication, the symbol ECw, is used to represent the electrical

conductivity of irrigation water and the symbol ECe is used to designate the electrical

conductivity of the soil saturation extract. The unit of electrical conductivity is deciSiemen per

meter (dS/m).

5.3 Sodium Adsorption RatioSodium is an unique cation because of its effect on soil. When present in the soil in exchangeable form, it

causes adverse physico-chemical changes in the soil, particularly to soil structure. It has the ability to

disperse soil, when present above a certain threshold value, relative to the concentration of total dissolved

salts. Dispersion of soils results in reduced infiltration rates of water and air into the soil. When dried,

dispersed soil forms crusts which are hard to till and interfere with germination and seedling emergence.

Irrigation water could be a source of excess sodium in the soil solution and hence it should be evaluated for

this hazard.

The most reliable index of the sodium hazard of irrigation water is the sodium adsorption ration, SAR. The

sodium adsorption ratio is defined by the formula:


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(1)

where the ionic concentrations are expressed in me/l.

A nomogram for determining the SAR value of irrigation water is presented in Figure 3 (US Salinity

Laboratory 1954). An exchangeable sodium percentage (ESP) scale is included in the nomogram to

estimate the ESP value of the soil that is at equilibrium with the irrigation water. Using the nomogram, it is

possible to estimate the ESP value of a soil that is at equilibrium with irrigation water of a known SAR

value. Under field conditions, the actual ESP may be slightly higher than the estimated equilibrium value

because the total salt concentration of the soil solution is increased by evaporation and plant trans-piration,

which results in a higher SAR and a corres-pondingly higher ESP value.

It should also be noted that the SAR from Eq 1 does not take into account changes in calcium ion

concentration in the soil water due to changes in solubility of calcium resulting from precipitation or

dissolution during or following an irrigation. However, the SAR calculated according to Eq 1 is considered

an acceptable evaluation procedure for most of the irrigation waters encountered in agriculture. If significant

precipitation or dissolution of calcium due to the effect of carbon dioxide (CO2), bicarbonate (HCO3-) and

total salinity (ECw) is suspected, an alternative procedure for calculating an Adjusted Sodium Adsorption

Ratio, SARadj. can be used. The details of this procedure are reported by Ayers and Westcot (FAO (1985).

5.4 Toxic IonsIrrigation water that contains certain ions at concentrations above threshold values can cause plant toxicity

problems. Toxicity normally results in impaired growth, reduced yield, changes in the morphology of the

plant and even its death. The degree of damage depends on the crop, its stage of growth, the

concentration of the toxic ion, climate and soil conditions.

The most common phytotoxic ions that may be present in municipal sewage and treated effluents in

concentrations such as to cause toxicity are: boron (B), chloride (Cl) and sodium (Na). Hence, the

concentration of these ions will have to be determined to assess the suitability of waste-water quality for

use in agriculture.


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A nomogram for determining sodium adsorption ratio (US Salinity Laboratory 1954)

5.5 Trace Elements and Heavy MetalsA number of elements are normally present in relatively low concentrations, usually less than a few mg/l, in

conventional irrigation waters and are called trace elements. They are not normally included in routine

analysis of regular irrigation water, but attention should be paid to them when using sewage effluents,

particularly if contamination with industrial wastewater discharges is suspected. These include Aluminium

(A1), Beryllium (Be), Cobalt (Co), Fluoride (F), Iron (Fe), Lithium (Li), Manganese (Mn), Molybdenum (Mo),

Selenium (Se), Tin (Sn), Titanium (Ti), Tungsten (W) and Vanadium (V). Heavy metals are a special group

of trace elements which have been shown to create definite health hazards when taken up by plants. Under

this group are included, Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Mercury

(Hg) and Zinc (Zn). These are called heavy metals because in their metallic form, their densities are greater

than 4g/cc.


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5.6 pHpH is an indicator of the acidity or basicity of water but is seldom a problem by itself. The normal pH range

for irrigation water is from 6.5 to 8.4; pH values outside this range are a good warning that the water is

abnormal in quality. Normally, pH is a routine measurement in irrigation water quality assessment.

6 Types of Radioactive wastesSince the splitting of the atom, both uranium and plutonium have been used to create bombs, provide

medical supplies, and furnish energy. Not surprisingly, these uses create waste management problems:

what do you do with materials that stay radioactive for tens of thousands of years? The disposal of most

radioactive materials is regulated under the Atomic Energy Act of 1954 and subsequent amendments, as

well as by a radioactive material licensing program established by the Uranium Mill Tailings Radiation

Control Act of 1978. While some states are subject to direct control by the Nuclear Regulatory Commission

(NRC), a federal agency, Texas has been delegated authority by this agency and its predecessors and has

its own laws and regulations relating to the use of radioactive materials and radioactive waste disposal.

Radioactive waste has four main categories: low-level radioactive waste, high-level radioactive waste,

naturally occurring radioactive material, and transuranic waste.

6.1 Low-level Radioactive WasteLow-level radioactive waste includes all tools, instruments, pipes, syringes, paper, water, soils, and

protective clothing such as gloves contaminated with radioactive materials. Nationwide, about 80 percent of

low-level radioactive waste by volume is from nuclear power plants. Low-level "fuel-related" radioactive

wastes such as sludge, resins and evaporator bottoms from cleaning the large volumes of water used at

nuclear power reactors, and clothes, paper, and filters contaminated by radioactive waste make up one

category of nuclear-generated waste. Low-level "neutron-activated waste" from the intense bombardment

of reactor parts with radioactive neutrons is a second category of low-level radioactive waste. Finally,hospitals and other medical facilities also produce low-level radioactive wastes. About 1.4 million cubic feet

of low-level radioactive wastes were disposed of in the United States in 1991enough to fill about 280

boxcar loads. In Texas, it is believed that by 2007, there will be approximately 2 million cubic fee of low-

level radioactive waste needing disposal. Currently, two commercial sites are receiving low-level

radioactive waste in South Carolina, and Utah.


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In Texas, mining, power plants, industries, hospitals, and university research facilities generate about

20,000 cubic feet per year of low-level radioactive waste. By volume, about one-third of this low-level

radioactive waste comes from Texas's two nuclear power reactors: the South Texas Project in Matagorda

County, and the two-unit Comanche Peak Project in Somervell County.

By the amount of radioactivityas measured in a radioactivity scale known as curiesnuclear power

plants account for at least 70 percent of the state's low-level radioactive waste. While most radioactive

waste produced in Texas stays radioactive less than 100 years, about one percentagain associated with

power plantswill remain radioactive for thousands and even hundreds of thousands of years.

Federal and state definitions of low-level radioactive waste differ. In Texas, low-level radioactive waste

includes radioactive waste that has a half-life of 35 years or less and fewer than 10 nanocuries per gram of

transuranics, as well as wastes with half-lives of more than 35 years if special criteria for the disposal of the

waste are established by the TCEQ.*The federal definition, on the other hand, considers any radioactive

waste that has less than 100 nanocuries per gram of transuranics low-level.

Texas's nuclear plantsas well as many of the state's universities and industriessent their radioactive

wastes to a low-level radioactive facility in Barnwell, South Carolina, until July 1994, when the facility

temporarily closed. Since then, the facility has reopened and both the Barnwell and a similar facility in Clive

Utah -- accept low-level radioactive waste from Texas generator. However, the Barnwell facility will stop

accepting waste from Texas beginning in 2008 and the Utah site only accepts certain kinds of low-level

radioactive waste. The two nuclear plants in Texas currently store their nuclear wastes on-site in above-

ground facilities, while hospitals and universities either store such waste on-site or send it to a centralized

storage facility in Fort Stockton, Texas.There are an estimated 60 sites throughout Texas which store low-

level radioactive waste.

Low-level radioactive waste regulation falls under the jurisdiction of both the TCEQ and the Texas

Department of Health's Bureau of Radiation Control. While TCEQ regulates disposal of low-level waste andhas the authority to issue a license for a disposal facility, the TDH regulates and licenses the use, transport,

and storage of radioactive materials.

Under the federal Low-Level Radioactive Waste Policy Act of 1980 and 1985 amendments, states are

expected to arrange for disposal of low-level waste generated within their borders -- other than those
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wastes generated by federal weapon facilities -- or form a compact with other states to create a single

disposal site, which may refuse to accept waste from other states not in the compact. In 1981 the Texas

legislature created the Low Level Radioactive Waste Disposal Authority to develop a state site to manage

these wastes. In 1991 the legislature ordered the Waste Disposal Authority to locate the site in Hudspeth

County, and in 1992 a site was preliminary approved in Hudspeth County, about seven miles from Sierra

Blanca. In 1993, Texas formed a compact with the States of Vermont, and Maine to dispose of low-level

radioactive waste from these two states and from Texas in Texas, which was later approved by the U.S.

Congress.In 1996 the then-TNRCC proposed a draft permit for the site. However, several individuals, cities,

counties, and organizations from both sides of the border opposed the permit, and in 1997 the State Office

of Administrative Hearings ordered a hearing to decide whether to recommend denying or granting the

permit. In July 1998 the hearings examiners in the case recommended that the TNRCC deny the permit

because the applicant failed to characterize the fault directly beneath the site and failed to address potential

negative socioeconomic impacts from the proposed facility.*In October 1998 the TNRCC commissioners

denied the permit. In 1999, the Texas legislature eliminated the TRLLWDA, transferring all of its functions

to the TNRCC. Finally, in 2003, the Texas Legislature approved and the governor approved HB 1567,

which created a process for a private entity to hold a license to dispose of low-level radioactive waste, and

also allow another similar facility -- which could be owned by the same company although the wastes would

have to be disposed of separately -- to accept low-level federal radioactive waste from Department of

Energy (DOE) weapon or other facilities.

Under the legislation, the TCEQ has written rules for how it will accept applications to dispose of the

radioactive waste, and applications would need to be received by January of 2004. Applicants would need

to submit an application fee of $500,000. The disposal site would be run and managed by the private

company, but after a time period would revert to state ownership. Because of the way both the legislation

and the subsequent rules are written, it is most likely the waste site would be located in Andrews County in

West Texas. Waste Control Specialist, a private waste management company, currently manages a mixed

hazardous waste landfill and radioactive storage facility in Andrews County and has proposed disposingand managing low-level radioactive waste there. Another company Envirocare has in the past proposed

building a facility to accept low-level radioactive waste in several counties in West Texas. It is expected that

one or more of these companies would apply for a permit to manage low-level state and federal radioactive

waste. Nonetheless, the application is certain to generate some opposition, and a decision will not be

reached on approving such a site for several years.
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While it is difficult to estimate how much waste would be buried at such a site, estimates of "compact"

waste -- low-level radioactive waste in Texas, Vermont and Maine -- are between two and three million

cubic feet, while the DOE expects to generate hundreds of millions of cubic meters of low-level radioactive

waste by 2007. Under the bill, up to 162 million cubic feet of DOE waste could be disposed of in Texas.

6.2 Intermediate-level WasteContains higher amounts of radioactivity and may require special shielding. It typically comprises resins,

chemical sludges and reactor components, as well as contaminated materials from reactor

decommissioning. Worldwide it makes up 7% of the volume and has 4% of the radioactivity of all radwaste.

It may be solidified in concrete or bitumen for disposal. Generally short-lived waste (mainly from reactors) is

buried, but long-lived waste (from reprocessing nuclear fuel) will be disposed of deep underground.

6.3 High-level Radioactive WasteHigh-level radioactive waste includes radioactive material that results from the reprocessing of nuclear fuel,

from spent fuel rods removed from a nuclear power reactor (a machine that splits atoms to make

radioactive heat to boil water used for electricity generation); and from nuclear weapons. High-level

radioactive waste is currently being stored on-site at weapons manufacturing plants and power plants

around the nation until a permanent disposal site can be located.*One potential site, Yucca Mountain in

Nevada, is being considered as a repository for high-level waste, including spent nuclear fuel, although it

has generated fierce opposition. By 1990 the nation's nuclear plants had produced more than 20,000 tons

of high-level radioactive waste. Texas's two nuclear power plants produce spent fuel rods and other high-

level nuclear waste, which is stored in pools of water at the reactors.6.4 Naturally Occurring Radioactive Materials

Naturally occurring radioactive materials (often referred to as NORMs), can be found virtually anywhere. It

is estimated that the average person in the United States is exposed to about 360 millirems of radiation

from natural sources each year. In Texas, NORM is found in drinking water, and also includes waste

resulting from the mining of uranium and phosphate and from a number of other industrial activities, such

as oil and gas production. Themining of uraniumresults in mountains of radioactive waste referred to as

"tailings"one example of material classified as naturally occurring radioactive material. Tailings are the
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radioactive soil and sand left on the ground after uranium ore has been crushed and processed for its

radioactivity. These wastes contain uranium and radium as well as a number of toxic chemicals. Increased

incidence of cancer in some mine workers has been associated with their exposure to these wastes.

In addition, coal power production, oil and gas exploration and production, fertilizer production, and water

treatment can all produce wastes classified as naturally occurring. For example, the insides of oil extraction

pipes may be coated with radium, or radium may be brought up to the surface while drilling for oil. Naturally

occurring radioactive wastes are managed apart from other radioactive and toxic wastes.

Naturally occurring radioactive material waste is regulated in Texas by three different agencies. The Texas

Department of Health's Bureau of Radiation Control regulates the receipt, possession, strorage, use and

treatment of NORM, while the Railroad Commission of Texas regulates the disposal of oil and gas NORM

waste. Finally, the Texas Commission on Environmental Quality regulates disposal of all other NORM

waste that does not result from oil and gas production.

In oil and gas exploration, development and production, NORM originates in underground formations and

can be brought to the surface in the formation water that is produced along with oil and gas, usually in the

form of radium 226 and 228 and radon gas. Concentrations of these NORM wastes can occur in sludge

that accumulates in oil pits, or become present in well tubulars or other equipment. Under RCT regulations,

oil and gas waste containing NORM can no be injected back underground or discharged into surface

waters without a permit. Oil and gas producers that are removing pipes from the ground which might

contain traces of uranium or other radioactive materials must first get a license from the Department of

Health. If they intend to export the waste to another site in Texas, that disposal site must be licensed by the

Railroad Commission. As of January 1998, only two off-site disposal sitesNewpark Environmental

Services in Winnie, Texas, and Lotus, L.L.C. in Andrews Countywere authorized by the Railroad

Commission to receive naturally occurring radioactive material waste. Both use pits and injection wells to

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6.5 Transuranic WasteTransuranic waste, or TRU, includes waste containing plutonium and other elements heavier than uranium

which contain more than 100 nanocuries of alpha-emitting isotopes. Transuranic waste is produced mainly

from the reprocessing of spent nuclear fuel rods, nuclear weapons production, and reactor fuel assembly.

The main producer of transuranic waste is the Department of Energy's nuclear weapons production

facilities. In 1999 the department began sending transuranic waste for disposal at natural underground salt

formations near Carlsbad, New Mexico. This locale is known as the Waste Isolation Pilot Plant, or WIPP.

While the site was certified by the EPA in 1998, it still must receive an operating permit from the New

Mexico Environment Department before it can receive other types of radioactive and hazardous waste.

In Texas, tons of plutonium from the nation's nuclear arsenal are being stored at the Pantex nuclear

weapons plant some seventeen miles northeast of Amarillo in Carson County. About 2,000 nuclear

weapons are being dismantled there each year and stored at the plant site. The Pantex plant is owned by

the Department of Energy and operated under contract by Mason and Hangar-Siles Mason Co. In 1994 the

plant was declared a Superfund site and is currently

6.6 Wastes from the nuclear fuel cycleRadioactive wastes occur at all stages of the nuclear fuel cycle - the process of producing electricity from

nuclear materials. The fuel cycle comprises the mining and milling of the uranium ore, its processing and

fabrication into nuclear fuel, its use in the reactor, the treatment of the used fuel taken from the reactor after

use and finally, disposal of the wastes.

The fuel cycle is often considered as two parts - the "front end" which stretches from mining through to the

use of uranium in the reactor - and the "back end" which covers the removal of used fuel from the reactor

and its subsequent treatment and disposal. This is where radioactive wastes are a major issue.

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