Environmental Lab Final

In statistics, “continuous data” is a variable that may have any value

True

Food and drinks are allowed only in containers with lids in laboratory spaces where materials that pose a health risk are present

False

Three major issues considered in environmental engineering

Land, soil, and water quality

True

Water hardness is caused by the presence of salts dissolved in water, primarily calcium and magnesium

National primary drinking water regulations are legally enforceable standards that apply to public water systems

True

____ hardness is caused by the present of calcium and magnesium, which do not decompose and do not precipitate during boiling water

Permanent

Effects of temperature change in water include

Reduction of oxygen carrying capacity of water

Fixed suspended solids represent the organic fraction of solids in a water sample

False

Biochemical Oxygen Demand is the amount of oxygen required to oxidize only organic matter in wastewater

True

Treatment operations aimed explicitly at removing turbidity

Coagulation, Flocculation, Sedimentation

Permanent hardness can be removed using a water softener or ion exchange column

True

Change in the solubility of nutrients and heavy metals is an effect of pH change in the water

True

As the water warms, the amount of dissolved oxygen in the water ___

Decreases

National ____ drinking water regulations are non-enforceable guidelines for contaminants that may cause cosmetic and aesthetic effects in drinking water

Secondary

Effects of turbidity change in water include

Interference with sunlight penetration, thermal pollution and decrease of oxygen levels

Total suspended solids refer to particles that will not pass through a 2-micron filter

True

During the coagulation process, when two colloidal particles approach each other, they are subjected to two significant types: electrostatic and interm0lecular forces

True

____ is the amount of oxygen required to oxidize organic and inorganic matter is wastewater

COD

If a sample is analyzed by COD and BOD methods, which method might give a lower value?

BOD

Total suspended solids are filterable solids that pass through a filter with a pore size of 2.0 microns

False

COD values are greater than BOD values, especially when biologically resistant organic matter is present

True

Three key properties of a coagulant are

Non-toxic, insoluble at neutral pH, and trivalent cation

___ is a chemical process to promote aggregation of colloidal material

Coagulation

___is the application of engineering principles to improve and maintain the environment for the protect of human health and at-risk ecosystems

Environmental Engineering

Environmental Engineering issues include

Air, land, and water quality

Air quality addressed

smog, respiratory and other illnesses, acid rain, and global warming

Air pollutant

A known substance in the air that can cause harm to humans and the environment

Greenhouse effect

The natural warming of the earth that results when gases in the atmosphere trap heat from the sun that would otherwise escape into space

Global warming

An increase in the average air temperature of the earth

Land quality issues include

Land pullution, overuse of natural resources, renewable and non-renewable resources

Land pollution pollutes the environment and our ecosystems, causing __

Health problems, harm to wildlife, and disrupt the balance of nature

Water quality issues include

Water pollution, oxygen depletion, treatment and disinfection, and storage

What is critical thinking?

It is the ability to analyze and evaluate problems

Critical thinking framework pillars

Intellectual traits, elements of thought/reasoning, intellectual standards

Qualitative data

Non-numerical information that categorizes things

Quantitative data

Information that can be measured and expressed numerically

Discrete data

Type of countable, non-divisible data that consists of distinct, separate values

Continuous data

Values that can take on any value within a given range, often measured rather than counted

Mean

Arithmetic average

Median

Middle value of a ordered data set

Mode

The most frequent value in a data set

Parametric normality

Symmetric, bell-shaped

Non-parametric normality

Skewed or multi-modal

Dependent data

Value of one provides information about the other

Independent data

Knowing one gives no information about the other

Water quality is ___

The condition of water for a purpose

Specific characteristics determine water quality

Physical, chemical, biological, and radiological characteristics

Physical characteristics of water

Color or turbidity, temperature, taste, and odor

Chemical characteristics of water

Composition and concentrations

Biological characteristics of water

Essential to public health, like pathogens, bacteria, and viruses

Radiological characteristics of water

When water comes into contact with a radioactive substance

Water quality indicators include

Temperature, dissolved oxygen, pH, nitrates and phosphates, turbidity, bio-indicators, and hardness

Effects of temperature change on water quality

Affects the oxygen-carrying capacity of water, can stress aquatic organisms, and impact water density and conductivity

Effects of pH change on water quality

More acidic water can kill certain aquatic organisms, change in the solubility of nutrients and heavy metals, effect the taste of water

Effects of dissolved oxygen on water quality

High amounts can make drinking water taste better and an amount below 3 ppm can cause the most versatile fish to die

Effects of turbidity on water quality

Interfere with sunlight penetration, decrease oxygen, rises temperatures which can cause thermal pollution, spread of harmful microorganisms

Effects of salinity on water quality

High amounts can make it unsuitable for drinking, can cause deterioration of pipes, and can effect the taste of water

Effects of chlorine on water quality

Can react with organic material in drinking water and from Trihalomethanes (THMs), which can cause adverse health risks

Effects of nitrogen and phosphorus on water quality

Reduce water quality of recreation, high amounts to stimulate the growth of aquatic plants and algae, toxic for humans and animals

Bioindicators

Living organisms that provide information about the health of an ecosystem, like lichens and algae blooms

Hardness

Caused by the presence of salts dissolved in water, primarily calcium and magnesium

Effect of hardness on water quality

Can cause excessive soap usage, scaling, and precipitate form on hardware

Carbonate hardness

Caused by the presence of carbonates, hydro carbonates and hydroxides of calcium and magnesium, also called temporary hardness since it can be removed by boiling water or by addition of lime

Noncarbonate hardness

Caused by the presence of calcium and magnesium, which do not decompose and do not precipitate during boiling water, also called permanent hardness; can only be removed using a water softener or ion exchange column

Who regulates water quality?

The environmental protection agency (EPA) and the department of environmental quality (DEQ)

Clean water act

Establishes the basic structure of regulating discharges of pollutants into the water and regulating quality standards for surface waters

Safe drinking water act

Sets standards for drinking water quality and oversees the states, localities, and water suppliers who implement those standards

Purpose of water treatment

To remove contaminants or reduce them to a concentration that makes the water safe to drink

Palatable water

Water does not have a taste or odor, aesthetically pleasing

Potable water

Water that is free of chemicals, microorganisms, and other contaminants, so it is safe to drink

Limited treatment plants

Have a high-quality water source and employ specific treatment to address specific water quality issues, typically only used for the treatment of groundwater as a raw water source

Coagulation treatment plants

Typically used to treat surface water

Softening treatment plants

Used to treat waters that have a high hardness level, usually groundwater

Coagulation

The addition of chemicals to promote aggregation of colloidal material into larger particulates

Rapid mixing

The chemicals are quickly and uniformly dispersed in the water

Flocculation

Designed to permit gentle contact between particulates, to promote floc growth while avoiding floc shear

Sedimentation

Settlement of particles using gravity

Filtration

Removal of particles by sieving through a granular media or the application of UV radiation

Disinfection

Addition of chemicals to reduce pathogenic organisms to levels that will not cause diseases

Wastewater treatment plants

Facilities that use mechanical, physical, chemical, and biological processes to remove pollutants from wastewater, transforming it into effluent that is safe for discharge into the environment or reuse

Industrial wastewater treatment plant

Handle wastewater from factories and industrial processes, which may require specialized treatment of particular contaminants

Municipal wastewater treatment plant

Facility that treats domestic and municipal wastewater from homes and businesses

Phases of a municipal wastewater treatment plant

Preliminary, primary, secondary, and tertiary treatment

Preliminary treatment

Intended to protect the wastewater treatment plant’s equipment

Primary treatment

Removes settleable organic/inorganic solids by sedimentation, and removes materials that will float, scum, by skimming

Secondary treatment

Biological treatment wherein aerobic microorganisms degrade the organic material to produce additional microbial biomass and oxidized products

Aeration basin

Where the microbial biomass, wastewater, and dissolved oxygen are brought into contact

Secondary clarifier

Used to separate the microbial biomass from the treated wastewater

Tertiary treatment

Final cleaning process that improves wastewater quality before it is reused, recycled, or discharged to the environment

Coagulation sedimentation in tertiary treatment

Increases removal of solids

Filtration in tertiary treatment

Different types of filters, like sand and membranes, that remove suspended materials and bacteria

Reverse osmosis in tertiary treatment

Pressure is used to force effluent through a membrane that retains contaminants

Nutrient removal in tertiary treatment

Additional biological treatment beyond the secondary stage

Solids in water

Any suspended or dissolved particles present in water that remain as a residue after evaporation and subsequent drying

Suspended solids

Particles floating or suspended in water, but not dissolved

Dissolved solids

Substances fully dissolved in water and are not visible

Effects of total suspended solids in water

Can make drinking water unpalatable, affect water clarity, can serve as a carrier of toxins, cause scum buildup, release odors, and reduce the efficiency of wastewater treatment plants

Total dissolved solids

Any organic matter or inorganic salts that have dissolved in a water system

Evaporation

A direct measurement of TDS where a sample is evaporated and the remains are weighed

TDS meter

An indirect measurement that measures the electrical conductivity