Drinking Water

Bioconcentration Calculations

In Chapter 2 and 3, we discussed bioconcentration and looked at DDT data from a food chain on Long Island, NY (Table 2.3). The data from Table 2.3 are reproduced in Table 10.10, where we used it to calculate bioconcentration factors (BCFs) for each animal species. Each BCF is calculated by dividing the DDT concentration in each animal by the water concentration. As you can clearly see, DDT is increasingly bioconcentrated as we move up the food chain, from 800 in the first tropic level to...

Health Risk Calculations For Noncarcinogens

Threshold Pollutant

In considering the carcinogenic effects of chemicals, there is no threshold dose of a chemical to which an animal species can be exposed safely. In risk calculations for noncarcinogens, though, it is accepted that there is a threshold chemical concentration, below which the chemical is not harmful. These values are calculated by taking a population of animals, exposing them to increasing doses of the chemical, and observing health effects. A generic plot of such an experiment is shown in Figure...

Monitoring Wells

Shallow Well Drilling Auger Bits

Taking environmental samples to monitor the concentration of a pollutant in river, lake, and atmospheric systems is relatively easy, although there are strict procedural guidelines for sampling and analysis. In these systems, you can see and feel the sample matrix. However, the sampling of groundwater is very different. For simplification purposes, we will limit our discussions primarily to saturated groundwa-ter systems, but remember that contamination also can occur between the ground surface...

The History Of The Environmental Protection Agency Us Epa Administrators

As we saw in the last section, the idealism, activism, and momentum of the environmental movement coalesced in the first celebration of Earth Day on April 22, 1970. Earth Day lives in popular memory to this day as a joyous and life-affirming moment in American history (Lewis, 1985, p. 3). Protestors delivered strong messages to the community, the president, and the government as oil-coated ducks were dumped on the doorstep of the Department of the Interior A student disguised as the Grim Reaper...

Putting It All Together Margin Of Error Uncertainty Of The Entire Estimation Process

We are finally at the culmination of a long and complicated discussion of source characterization, chemistry, fate and transport modeling, and now risk assessment. But how good are our risk assessment values We have discussed a number of precautions in every chapter. The major ones include the following 1. Every number we generate in our modeling efforts depends on an accurate characterization of the waste site or polluted system with respect to pollutant mass dumped or contained in the system....

List Of Contaminants And Their Mcls Epa 816F02013 July 2002

List of Contaninants and Their MCLS (EPA 816-F-02-013, July 2002) (mg L)2 (mg L)2 Potential Health Effects from Ingestion of Water Sources of Contaminant in Drinking Water Heterotrophic plate n a TT3 (including fecal coliform and E. coli) Gastrointestinal illness (e.g diarrhea, vomiting, cramps) Gastrointestinal illness (e.g diarrhea, vomiting, cramps) HPC has no health effects it is an analytic method used to measure the variety of bacteria that are common in water. The lower the concentration...

The Determination Of The Biochemical Oxygen Demand Bod Of Sewage Influent Bod5 Andor Bod20

To determine the biochemical oxygen demand (BOD) in a domestic wastewater sample. Background. The focus of this laboratory exercise will be to determine the amount of oxidizable organic matter (sewage) in a wastewater sample. As we discussed in the dissolved oxygen chapter, the term DO refers to the chemical measurement of how much dissolved oxygen is present in a water sample, expressed in mg L. The biochemical oxygen demand (BOD) is an estimate of how much total DO is required to...

Calculation Of The Free Metal Ion Concentration In Natural Waters

3.2.1 Calculating Chemical Equilibria Students begin their study of chemical equilibrium in general chemistry with basic equilibrium expressions and Le Chatelier's principle. However, these courses rely on many simplifications regarding equilibria. These simplifications were fine when you were working in simple solutions solutions containing only one or two salts at low concentration but are rarely acceptable in environmental chemistry (as in groundwater, estuary, and ocean water). Courses in...

Historic Examples Of Where Fate And Transport Modeling Are Useful

Waters E2695 Hplc Pump Diagram

There is no lack of unfortunate and disastrous pollution events that fate and transport models have been applied to in an effort to better understand and be able to predict pollutant movement in the environment. These are divided into surface water, groundwater, and atmospheric events. You may recall many of the events, discussed below, from news reports or case studies that you have covered in other classes. The Release of Biochemical Oxygen Demand (BOD) Waste to Streams. One of society's...

Equilibrium Sorption Phenomena

We have already discussed several equilibrium processes, and these are summarized in Table 2.8 along with some new ones for this section. Most chemists, especially those dealing with pollutant fate and transport phenomena, prefer to work with a system at equilibrium. This makes the mathematical expressions much simpler, and it allows us to ignore many poorly understood kinetic processes. In this section, we will look at pollutant sorption (attraction) phenomena between the aqueous phase and...

Stratification Of Lake Systems

Most lakes undergo some form of thermal stratification during the year. Stratification is a process in which differential heating or cooling occurs and two climates are set up in the lake. If a lake undergoes only one stratification event during the yearly cycle, it is referred to as a monomictic lake. The most common stratification scenario is illustrated in Figure 5.3b. Figure 5.3a shows the unstratified lake during Figure 5.3. Stratification of lakes during annual cycles. Figure 5.3....

Kinetics Of Transformation Reactions

In Chapters 2 and 3, we have looked at various chemical processes that are important in understanding how chemistry affects fate and transport. These have included acid-base, precipitation, and oxidation-reduction processes and sorption equilibrium. These processes affect the transport but do not necessarily account for any removal of pollutants from the system under study. As noted earlier, most sorption equilibrium reactions are reversible if they were not, we would not be concerned with...

The Determination Of Hardness In A Water Sample

In the past, water hardness was defined as a measure of the capacity of water to precipitate soap. However, current laboratory practices define total hardness as the sum of divalent ion concentrations, especially those of calcium and magnesium, expressed in terms of mg CaCO3 L. There are no known adverse health effects of hard or soft water, but the presence of hard waters results in two economic considerations (1) Hard waters require considerably larger amounts of soap to foam and clean...

Reactions And Equilibrium

The three basic types of chemical reactions are precipitation, acid-base, and oxidation-reduction. We covered precipitation to the extent necessary in Section 2.4.2 (and we will cover it again in Section 3.2.2). We will spend a little more time covering acid-base and oxidation-reduction reactions in this section. First, we will extend your knowledge of acid-base chemistry through the concept of buffers and pC-pH diagrams. By far the most important buffer system in nature is the carbonate...

Pollution Versus Contamination Pollutant Versus Contaminant

Is there really a difference between the terms pollutant and contaminant Some would argue no, while others will argue vehemently yes. In the United States, environmentalists and those working for Environmental Protection Agency (EPA) prefer the terms pollution and pollutant. But what makes a chemical a pollutant Basically this distinction is determined by where the chemical is located and how much of the chemical is present. For example, a bottle of mercury chloride is typically not considered...

Mathematical Models

Mathematical Models Drinking

Instantaneous (Pulse) Pollutant Input. If we assume the spill contaminates the entire thickness of the aquifer, as shown in Figure 8.22, an equation can be obtained using Laplace transformation to predict the pollutant concentration as a function of time or distance from the point source Figure 8.22. An illustration of an instantaneous (pulse) input of pollution to an aquifer. Figure 8.22. An illustration of an instantaneous (pulse) input of pollution to an aquifer. where x is distance from the...

And Amendments

The Clean Air Act is probably the most amended environmental act in U.S. history. While we would like to think an act is amended because of increased knowledge or tightening of pollutant emissions, this has not necessarily been the case with the Clean Air Act. Although, in general, air quality has improved since the introduction of clean air legislation in 1955, some critics of the process feel we have regressed in our efforts by deregulating what we are having trouble controlling or what we...

Putting It All Together Where Chemistry Enters Into The Modeling Effort

Edta Contamination Chemistry

We have covered many important and complicated chemical concepts in Chapters 2 and 3. But where do they all fit into the pollutant fate and transport modeling approach, and when is each important It depends on the pollutant and the environmental system under study, but we will attempt to summarize the role of chemistry in the modeling effort. We will divide our discussions into a metal pollutant and a hydrophobic (organic) pollutant, and important chemical processes are summarized in Table 3.3....

Kinetics Of The Sorption Process

Another factor that must be considered in determining equilibrium coefficients is the time scale required to reach equilibrium. Most studies of inorganic and organic pollutants find that a three-day equilibrium period is sufficient to obtain a constant Kd or Kp. However, this does not mean that true equilibrium concentrations within particle aggregates have been reached. For example, thus far we have limited our discussion to individual particles, but many particles in nature are large...

Remediation

No text on pollutant fate and transport would be complete without considering remediation of the contaminated system. Thus, each fate and transport chapter in this book (Chapters 5-9) will close with a section on remediation. Each environmental system discussed in this book presents a unique set of conditions, and thus problems, with respect to remediation. Issues specific to lakes include the hydraulic retention time, t0, introduced in Section 5.5.2, which is determined by the total volume of...

The Solid Waste Disposal Act Resource Conservation and Recovery Act RCRA and Amendments

Disposal of solid wastes produced by human activities has posed problems since humans gave up the nomadic lifestyle. As humans settled in larger and larger groups in isolated areas, wastes reached sufficient concentrations such that they were no longer naturally removed and waste management plans had to be created. Continued development of sessile and ever larger communities exacerbated the problem. Congress began to address an impending crisis after World War II, as the United States faced...

Important Factors In The Modeling Of Streams Conceptualization Of Terms

In order to describe a stream mathematically, we must first make a list of variables (mathematical symbols) for the important terms SA is the cross-sectional area of the stream (width, w, multiplied by average depth, d) (m2). Qi is the flow rate at the beginning of the section of the stream to be modeled (m3 yr). Qe is the flow rate at the end of the section of the stream to be modeled (m3 yr) (we usually assume that Qt is equal to Qe and we represent both by simply C(x) is the pollutant...

Physical Parameters Important In Pollutant Fate And Transport

In Section 8.4, we mentioned the importance of bulk density and porosity in relating Kd and Kp to retention (R) in a aquifer or column. These physical measurements are also important in estimating water velocity. In rivers and lakes, logically, the water flows downhill, and it is also generally easy to tell how fast the water is flowing with a tool as simple as a tennis ball. But in aquifers, where we cannot see the slope of the water table, it is difficult and in many cases impossible to...

Student Procedures

To 250-mL or 300-mL sample bottle full of sample, add 1mL MnSO4 solution, followed by 1 mL alkali-iodide-azide reagent. If your pipets are dipped into the sample (as they should be), rinse them before returning them to the reagent bottles. If the solution turns white, no dissolved oxygen is present. 2. Place stoppers on the sample bottles in a manner to exclude air bubbles and mix by rapidly inverting the bottle a few times. When the precipitate has settled to half the bottle volume, repeat the...

Suggested Papers For Class Discussion

L. Taylor, and J. F. McCarthy. Cotransport of cadmium and hexa-chlorbiphenyl by dissolved organic carbon through columns containing aquifer material. Environ. Sci. Technol. 26(2), 360-368 (1992). Dunnivant, F. M., M. E. Newman, C. W. Bishop, D. Burgess, J. R. Giles, B. D. Higgs, J. M. Hubbell, E. Neher, G. T. Norrell, M. C. Pfiefer, I. Porro, R. C. Starr, and A. H. Wylie. Water and radioactive tracer flow in a heterogeneous field-scale system. Groundwater...

Remediation Of Polluted Streams Systems

As we saw in our case study for this chapter, rivers are highly dynamic systems and pollutants move rapidly through the system. In many cases, the movement is so rapid that we do not have time to respond and clean up the system before the pollution has moved on. If fact, pollution in a river system is a moving target, and by the time we have adequate technologies in place to respond to a pollution spill, the pollution has moved to another section of the stream. Often, the best we can do is...

The Concept Of Risk

What is an acceptable risk This is a major, and largely unanswerable, question. In order to attempt to answer this question, we will first look at commonly accepted risks that each of us exposes ourselves to every day. Table 10.1 shows the annual risk associated with a variety of actions. These are listed in decreasing degree of risk and show that smokers routinely accept an increased mortality risk of 3600 per million that is, for every one million smokers, 3600 or 0.36 of them will die each...

Methods For Determining Kd AND Kp

Determining Fraction Organic Carbon

As discussed in Chapter 2, distribution coefficients are central to our modeling of equilibrium sorption processes in environmental media. First, we will mathematically define several terms (refer to Table 2.6 for a description of their use) For partitioning between the aqueous phase and dissolved organic matter K _ Conc. of pollutant in DOM (mg kg) DOM Conc. of pollutant in water (mg L) For distribution between the aqueous phase and particles in solution K _ Conc. of pollutant on particle (mg...

Ingestion of Contaminated Fish and Shellfish

We not only have to be concerned with the intake of pollutants from water, but also with foods that come from polluted water sources. Aquatic species often accumulate pollutants into their muscle and organ tissue, which we use for food. Thus, significant doses of pollutants can result from eating these polluted organisms. A recently discovered example is the presence of mercury in several species, especially those at the top of the food chain. The dose of a pollutant can be calculated by where...

Basic Input Sources Wastewater Flow Rates And Bod Levels

Settling Tank Basics

The Streeter-Phelps equation is designed to model the oxidation of any constant (step) input of oxidizable waste flowing to streams. Thus, the input source can be a variety of point and non-point sources, including the waste from domestic sewage plants, food-processing facilities, and inputs from livestock feedlots and agricultural settings. The only wastewater parameters that must be known are the flow rate of wastewater, the temperature of the wastewater, the DO of the wastewater (usually...

Sources Of Pollution

As with types of waste, there are many ways of categorizing sources of waste or potential pollutants . We will only mention a few of the more useful approaches and give examples of generated volumes from major industrialized countries. First, we will discuss point and nonpoint sources. Sources of pollutants are commonly divided into one of two types, point or nonpoint sources. Point sources are well-defined sources such as the end of a pipe, smoke stack, or drain. Nonpoint sources are less well...

Uses and Points of Contact

The group of commonly used endocrine disruptors is highly varied, and they are used in a wide variety of modern consumer products. Basically anything resembling a type of plastic contains potential endocrine disruptors. Perhaps the most direct source of endocrine disruptors to people is from foods, which are exposed to EDCs either by direct application or as a result of leaching from packaging materials (Casajuana and Lacorte, 2003). Many food products are contained in material, including...

Mathematical Development Of Model

9.4.1 Step Input (Plume Model) of Pollutant Using the many assumptions stated earlier and the estimated horizontal and vertical dispersion coefficients, a model Eq. (9.1) for the steady-state plume can be derived, using differential equation techniques to estimate the pollutant concentration at any point (x, y, and z) downwind from the continuous source. This is referred to as the steady-state plume model. where C(x, y, z) is the concentration of pollutant in the plume as a function of x, y,...

Inhalation of Airborne Vapor Phase Pollutants

Chapter 9 discussed ways of estimating the downwind pollutant concentration of a pollutant from a chemical spill. Other atmospheric exposure routes include vapors from household products, gasoline fumes from automobile filling operations, and volatilization of pollutants from household water. Another common inhalation route is breathing vapors while showering with polluted water. Estimates of CDI from vapors can be calculated by where CA is the pollutant concentration in the air (mg m3), IR is...

Health Risk Calculations For Carcinogens

Perhaps the most disputed, but very important, aspect of determining the effects of a pollutant on human health is our attempt to estimate the increase in cancer risk in a population exposed to the pollutant at a specific concentration. We start with the standard approach of developing a dose-response curve, such as the one shown in Figure 10.1, by exposing an animal to increasing concentrations of pollutant. After a given time period days, months, or even a lifetime the animal is sacrificed...

The Federal Insecticide Fungicide and Rodenticide Act FIFRA

The passing of the FIFRA in 1947 was the first attempt to regulate the manufacture and use of pesticides across the nation. Although the enforcement efforts, and thus the act itself, were weak, the act was a starting point for a major movement. The act was amended in 1972 in 1988, to regulate all phases of pesticide sale, use, handling, and disposal and in 1996, under the Food Quality Protection Act FQPA , to establish tolerances for pesticide residues in food. The heart of FIFRA is the...

Safety and Hazards

As in all laboratory exercises, safety glasses must be worn at all times. All of the chemicals used in this laboratory are relatively safe, but standard laboratory cautions and safety should be practiced. You will spill and spread dilute flourescein solution everywhere in this lab. Dilute concentrations are safe when spilled on your skin, but may turn your skin yellow for a brief time. We recommend wearing latex gloves during this laboratory exercise. Student Procedures. Your laboratory...

Determination Of A Claywater Distribution Coefficient For Copper

To determine the distribution coefficient of a metal on a characterized soil. Background. Perhaps the most important fate and transport parameter is the distribution coefficient, Kd. The distribution coefficient is a measure of adsorption phenomena between the aqueous and solid phases and is fundamental to understanding processes responsible for the distribution of pollutants in aquatic systems. For applications of the distribution coefficient to fate and transport modeling of...

Total Suspended Solids TSS and Total Dissolved Solids TDS Measurements

In this procedure, you will first use 100mL of your sample to perform the most commonly used solids measurement, the total suspended solids (TSS). This requires you to filter a known volume of sample through a pre-heated and pre-tared glass-fiber filter, to remove the suspended solids. The difference between the initial (just filter) and final (filter with solids) weights, divided by the volume of sample, will yield the TSS. The TSS measurement accounts for all solids that do not pass...

Total Suspended And Dissolved Solids In Water Samples

To determine the amount of suspended and dissolved solids in water samples. Background. Environmental waters may contain a variety of solid or dissolved impurities. In quantifying levels of these impurities, suspended solids is the term used to describe particles in the water column. Practically, they are defined as particles large enough to not pass through the filter used to separate them from the water. Smaller particles, along with ionic species, are referred to as dissolved...

The Determination Of Alkalinity In Water Samples

To determine the alkalinity of a natural water sample by titration. Background. Alkalinity is an expression of a water's ability to neutralize acids. Therefore, alkalinity measurements are important for considering the fate of acidic industrial pollution emitted directly into our waterways and as acid precipitation. Alkalinity is also a measure of a water's buffering capacity, or its ability to resist changes in pH upon the addition of acids or bases. Alkalinity in natural waters is...

The Federal Water Pollution Control Act the Clean Water Restoration Act the Safe Drinking Water Act and Amendments

Today we are concerned with both the availability (or scarcity) of water and the quality of the water. These concerns are best summarized by Charles C. Johnson, Former Assistant Surgeon General of the United States who said (www.epa.gov history topics fwpca 05.htm) Our water resources, more perhaps than any other, illustrate the interaction of all parts of the environment and particularly, the recycling process that characterizes every resource of the ecosystem. . . . Everything that man...

The National Environmental Policy

The National Environmental Policy Act (NEPA) is the Magna Carta of environmental law. Yet there are few today, even among environmentalists, who know what the law contains or understand the potential it once had, and may still have, to shape the U.S. federal policy toward the environment. The statute has been misunderstood ever since it was signed into law by President Nixon on January 1, 1970. There are four main purposes to the Act (NEPA, 1969) (1) to declare a national policy which will...

Mathematical Development Of Simple Transport Models

As discussed in Chapter 4, the derivation of the fate and transport equations used in this textbook requires that the student has taken linear algebra or differential equations. Since this textbook is designed for students who have only taken college chemistry and algebra, we will skip the derivation and simply state the governing fate and transport equation. A more mathematical derivation is given in the background section of Fate for the river and stream module. As we also discussed in...

Two Basic Mathematical Models For Lakes

As discussed in Chapter 3, the derivation of the fate and transport equations used in this textbook requires knowledge of linear algebra or differential equations. Since this textbook is designed for students who have only taken college chemistry and algebra, we will skip the derivation and simply state the governing fate and transport equation. A more mathematical derivation is given in the background section of Fate for the lake module. By substituting the mathematical terms for mass input,...

Important Factors In The Modeling Of Lakes Conceptual Model Development

In order to describe a lake system mathematically, we must first make a list of variables (mathematical symbols) for several terms Qi is the inlet flow from the main inlet to the lake (m3 yr). Qe is the outlet, or effluent, flow rate from the lake (m3 yr) (We usually assume that Qi is equal to Qe and we represent both by simply Q). Ci is the average pollutant concentration in the inlet to the lake (kg m3) (this value is zero in many cases). Ce is the average pollutant concentration in the lake...

Introduction To Pollutant Fate And Transport

An Integrated Approach With Chemistry, Modeling, Risk Assessment, and Environmental Legislation Whitman College Walla Walla, Washington Educational Solutions, LLC Mohawk Trail Regional School District, Shelburne Falls, Massachusetts A JOHN WILEY & SONS, INC., PUBLICATION Copyright 2006 by John Wiley & Sons, Inc. All rights reserved Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval...