EHST Ch. 16
__________________ through beds of sand, crushed anthracite coal, or diatomaceous earth further reduces the concentration of remaining suspended solids, including many bacteria and protozoans
filtration
what is done to sludge to reduce odor and the presence of pathogenic organisms
first its thickened through coagulant chemicals or dissolved air flotation, then stabilized through an anaerobic process
what are the leading cause of death in most developing countries
gastrointestinal infections when the pathogen is ingested
___________________________ "blue baby disease" occurs when bacteria in the babies intestinal track converts nitrates to toxic nitrites which bind with hemoglobin, displacing oxygen and producing a bluish discoloration of the skin
methemoglobinema
in developing countries, the main issue is ____________ ____________ of waterways from human waste that causes health problems
microbial contamination
under the safe drinking water act, EPA in 2009 established __________ ________________ __________ for 91 biological, chemical and radioactive pollutants
maximum contaminants levels
what regulations has the EPA set against sludge
maximum loading rates on soils for biosolids containing these contaminants
__________ _________ consist of several mechanical processes designated to remove larger suspended solids through screening and sedimentation
primary treatment
what has been done to reduce the incidence of epidemic diseases and to upgrade public health standards?
provision of adequate methods of sewage treatment, along with chlorination of drinking water
___________ _________ __________ act is a federal program to protect drinking water quality in the US
safe drinking water act
_______________ _______________ goal is to achieve a certain degree of effluent quality by using a sewage treatment plant with physical separation to remove settle able solids and a biological process to remove dissolved and suspended organic compounds
secondary treatment
contaminated _________ entering nearby streams or lakes may damage aquatic life
sediment
___________________ is when incoming raw water is detain in a quiet pond or tank for at least 24 hours to allow heavy suspended particles to settle out
sedimentation
what does biosolids management consist of
sludge treatment
______ is the single most absorbent of farmland runoff
soil
__________ and ___________ are the most notorious bacterial enteric diseases and responsible for millions of human deaths and illnesses worldwide
typhoid fever and cholera
In the Us, what is the most occurring problem associated with contaminated drinking water
unregulated private wells (approximately 17 million rely on private household wells for their water supply)
what does sludge mean
untreated biosolids
how long does the sludge process take
up to 60 days to complete
_______ _______ is the leading source pollutants impairing US bays and estuaries and the third most important contributor to degradation of water quality in lakes
urban runoff
_____ _______ ________ in many cities total pollutants exceeds that from industrial discharge
urban street runoff
chlorine is less than likely to kill __________ and _________, many which survive this treatment
viruses and parasites
why is lead an issue in drinking water
water because of lead service pipes leading from the water main to the house or within the home plumbing system as a result of corrosion when water passes through lead pipes or through pipes soldered with lead
what is point source of water pollution
when pollutants enter waterways at well defined locations -ex: through a pipe, ditch, sewer outfall, factories, sewage treatment plants and storm sewer outfalls
what is primary treatment for municipal sewage
where the water supply of a community comes in from separate storm and sanitary sewers (flows from homes and institutions into the municipal sewer)
why was the federal water pollution control act ineffective (5)
- designation of desire stream use were frequently modified to retain or attract industrial development - insufficient information was available on how pollutant discharges were affecting water quality -blame for violation was difficult, if not impossible, to assess when more than one source was discharging into a waterway - little attention was paid to the effects of pollution on the aquatic environment as a whole -only contaminants entering a waterway through pipe discharges were given much attention
what are contaminants commonly found in urban street runoff (7)
- road salt - sand -dirt -oil -grease/ heavy metal particles -fertilizers from lawns -bird and animal droppings
what does land application help prevent?
- stream pollution by keeping nutrients out of the water - it utilizes the same nutrients as fertilized for plants
What are most of the worlds water drainage basins pollutants (6)
- toxic chemicals - human and animal excrement - heavy metals - pesticides - salt - fertilizers
airborne particles include hazardous chemicals such as:
-PCB -mercury -lead -asbestos -fluoride -pesticides
what are septic system problems (6)
-Solids discharged into the absorption field could result in clogging and ponding -Accumulation of particles in the drainfield can lead to clogging and ponding -Septic tank may be too small for the householder's needs -Excessive household water use Insufficient of size of the absorption field -Soil to impervious to receive effluent -Tree roots clogging the effluent distribution lines
what are problems associated with indirect discharge
-Structural damage to sewer system and treatment plant -Interference with biological treatment processes -Biosolids Contamination
what is needed for pretreatment of indirect discharges according to the EPA
-Wastewater treatment facilities in communities that treat five million gallons of wastewater or more on a daily basis are required to have a pretreatment program -large industry to establish pretreatment programs at the facilities to ensure effluent is treated before it goes to the sewer
after the earthquake in Haiti, survivors living in dense rural areas were victims to what deadly out break? how many cases were caused? how many deaths?
-cholera outbreak -91,000 cases -2,100 deaths
what does primary municipal sewage contain (5)
-human feces and urine -waste from laundry -bathing -garbage grinding -dishwashing
what can reduce GI infections in developing countries
-installation of water purification -providing sanitary wastewater disposal -public education regarding personal -household hygiene
how to reduce urban street runoff (5)
-limited applications of lawns and garden fertilizers -proper disposal of pet waste -litter control on both public and private property -judicious use of road salt and sand -application of organic mulches to reduce erosion on urban areas
EPA drinking water standards for arsenic set at ________ mg/liter
0.05
what are the three major groups of pollutants
1. Conventional pollutants-include organic wastes high in BOD, suspended solids, acid, oil and grease. Such pollutants come from food processing plants, pulp and paper mills, steel mills, oil tanker spills 2. Toxic pollutants-include heavy metals such as cadmium, mercury, and lead, PCBs, benzene, chloroform, cyanide, arsenic. Such pollutants come from metal-processing industries, plastic manufacturers and chemical companies 3. Nonconventional pollutants-include nitrogen and phosphorous, iron, tin, aluminum, chloride. Sources can be traced through a variety of industries
lead exposure can be minimized by 2 simple actions
1. Don't drink the water if it has been in contact with pipes for more than six hours. The longer the water stands in pipes, the greater the amount of lead. Flush water before drinking or using it for cooking 2. Don't consume or cook with hot tap water, since lead dissolves more readily in hot water
4 ways to control toxic pollutants into waterways for agriculture
1. conserve tillage, terrace, contour plowing 2. applying pesticides when there is little wind and potential for heavy rain low 3. using non-persistent, low toxicity pesticides; disposing of containers properly 4. applying fertilizers or manures only when they can be incorporated into the soil
what are the primary treatment 4 steps
1. incoming flow passes through one of more screens 2. then enters a grit chamber (where the reduced velocity allows sand, gravel and other inorganic material to settle out) 3. air is injected to maintain aerobic conditions 4. followed by several hours in sedimentation tank. The solid material (sludge) that settles out in the sedimentation tank is regularly removed, dried or disposed of by one of several methods
what is required for achieving the goals of sewage treatment? (2)
1. killing pathogenic organisms present in human waster and to the greatest extent 2. removing organic wastes of converting them to inorganic forms so that after discharge they will not deplete the oxygen content of the receiving waters as they decompose
_____ billion people today still lack safe drinking water and ______ billion remain without adequate sanitary facilities
1.1 2.6
construction activities are ____-___ times more than the amount from agricultural lands
10-20
drinking arsenic contaminated drinking water over a period of ______-______ years can lead to chronic arsenic poisoning
10-20
theres approximately ___________ point sources of water pollution in the US
100,000
The EPA set the allowable limit for lead or copper in water at ________
15ppb
when was chlorination first introduced as a method of treatment
1903 in belguim
congress first passed the safe drinking water act in ___________
1974
approximately ___% of all Americans that do not have access to municipal sewer must utilize an on-site tank system for disposal of wastewater
30
estimate ___% of surface waters are contaminated with runoff from construction materials
5%
the world health organizations estimates that __________ people (mostly children) die each year due to fecally contaminated drinking water
5,500
manures from grazing lands or from livestock management facilities located adjacent to streams or lakes can contribute to ______ -________ times as many nutrients to waterways as do point sources
5-7
during primary treatment ____-____% of the suspended solids are removed
50-65
agriculture effects _____-____% of the nations surface water
50-70
more than _____ tons of sediment per acre per year can wash off site into streams during the construction period
500
today in the US, approximately ___% of the population live in the areas where domestic waste pass through a sewage treatment plant before being discharge
70%
it was estimated that typhoid fever killed ___-____ people per 100,000 population in the US each year
75-100
a major outbreak of typhoid fever claimed _________ lives in Chicago in 1885
90,000
______________ is also a parasitic infection often a major health problem in Mexico, eastern South America, western and southern Africa and China
Amoebiasis (amoebic dysentery)
________________ is one of the most common flagellated protozoans that is found in the human gut
Giardia lambia
Industries discharging directly into the waterways must obtain a _________ ________ specifying the allowable amounts
NPSES permit
Some people fear that ______ may be carcinogenic and should be removed from the water
THMs
what can sludge be used as
a fertilizer and a soil conditioner
where is chemical contamination in drinking water originated from
a wide range of activities such as chemical manufacturing, petroleum refining, iron and steel production, coal mining, wood pulp processing, textile manufacturing and agriculture
________ ________ ___________ is cause by interaction of iron pyrite with coal deposits is exposed to air and water during mining operations, a series of chemical reactions is initiated and the formation of a copper colored precipitate sulfuric acid
acid mine drainage
what does advance wastewater treatment (tertiary treatment) mean
additional treatment is needed when there is still contaminated substances from effluent that are causing water problems
the ______ of the home's plumbing is a major determinant of whether of not lead problems exists
age
in some cases, arsenic is a result of _____________ and _______________ effluent
agricultural and industrial
_____________ is the US's main source of water pollution
agriculture - a nonpoint source pollution
___________________ is a toxic heavy metal that can contaminate groundwater supplies through dissolution of naturally occurring arsenic- containing minerals in the earths crust
arsenic
____________ _________ is where sewage is treated on designated acres of wetlands and the suspended solids settle at the bottom, while the dissolved organic matter is broken down through a symbiotic association between bacteria and algae
artificial wetlands (designer swamps)
chlorine is only effective against __________
bacteria
what are trickling filters in secondary treatment
beds of crushed stone covered microbial slime consisting of bacteria and protozoans that absorb the organic material as the wastewater sprayed over the surface of the rocks
EPA requires construction sites to implement "________ ______ ___________" to control runoff
best practice management
how does chemical contamination enter drinking water
by direct or indirect discharges, surface runoff or fallout during precipitation episodes
how is sludge separated from the remaining liquid in secondary treatment
by settling and then the sludge is removed
what do many waste treatment plants convert their sludge to, to kill remaining pathogens
compost, heat-dry or otherwise treat their sludge
runoff from construction sites contain _________, _______, _________ and _______, _________ and ________
cement, asphalt, paint and cleaning solvents, oil and tar, and pesticides
______________ and ___________________ can be a source of runoff carried by water from fields into adjacent lakes and streams
chemical fertilizers and pesticides
__________________ can poison fish and promote algae growth
chemicals
what is Giardia resistant too
chlorination
in the 19th century, what were the 2 waterborne disease outbreaks that affected a lot of people
cholera and typhoid fever
________________ is when Alum (hydrated aluminum sulfate) is added to the water to cause smaller suspended solids to form flocs, which then precipitate to the bottom of the tank
coagulation
__________________ ____________ contribute to water pollution runoff from sites where homes, shopping centers, factories, or highways are highways under construction can contribute more sediment to waterways than any other activity
construction activities
other metals such as ______, ______, _______, _________ from mining operations contribute to contaminating streams
copper, zinc, manganese, magnesium
________________________ is another protozoan organism resistant chlorination
cryptosporidium
chlorine poses a safety problem at treatment plants sometimes causing what
cylinder leaks or system disruption
because chlorine is very destructive to aquatic life, what do many wastewater facilities do?
dechlorinate wastewater prior to releasing it downstream
__________ ________is industrial wastewater discharge that flow directly into a receiving stream or lake
direct discharge
______________________ is an introduction of chlorine(bromine, ozone, iodine, or ultraviolent light can be used as a disinfection), the disinfection is the most important method used to for killing pathogens in water. As an advantage over other disinfection methods, chlorine leaves a residual in the water to provide germ-killing potential as the water travels through the distribution system
disinfection
if runoff seeps through into shallow aquifers, it can contaminate ____________ __________ ________
drinking water wells
treated wastewater is to be used for what 3 things
drinking, irrigation or recreation
what does advance treatment involve
either one or combination of biological, chemical or physical processes
the major problem with the Clean Water Act of 1972, was a lack of ____________ ________ many states had dealing with water pollution
enforcement power
what are symptoms of bacteria water pollution
headache, muscle pains, high fever and constipation alternating with diarrhea (typhoid) and cholera, dysentery, and salmonellosis are typified by severe diarrhea (bloody in the case of dysentery) and vomiting
what does chlorination do
helps reduce deaths associated with waterborne disease and improve public health
in urban cities that produce a lot of sludge, what is one of the main wastewater treatment issues
how to properly dispose the sludge
_________ __________ is wastewater that go into the sewer system, where they first pass through the municipal sewage treatment plant before entering the waterway along with sanitary wastewater effluent
indirect discharge
prior to the SDWA, regulations on drinking water were left to _______________________ to enforce, if they did any enforcement at all
individual states
_____________ ______________ is effluent discharge from industry comprise the second major category of point sources
industrial discharges
what is the clean water action plan
it addresses the problem of polluted runoff by encouraging states and tribes to adopt enforceable controls on nonpoint sourses
_______________ ______________ involves spraying effluent from secondary treatment onto forest, pastures or croplands
land application
infants under 6 months old are at risk of blue baby disease because their stomach juices are ________ _______ than those of older children and adults
less acidic
___________________ associated with contamination from fertilizers or feedlot runoff, seepage from septic tanks of airborne fallout of nitrogen compounds by industry or motor vehicles
nitrates
in several mining states acid mine drainage constitutes leading _______ pollution problems
nonpoint
majority of states identify pollutants coming from _________ sources as the main reason they have been unable to attain their water quality goals
nonpoint
many waterways producing the largest pollutant contribution come from _______ sources
nonpoint
what are the most common species of enteric viruses associated with waterborne diarrheal illnesses
noroviruses, hepatitis A, poliomyelitis and rotavirus
The global death toll due to infectious diarrhea among all age groups is estimated at ______ billion illnesses and between ______-___ million deaths
one billion illnesses, 2-5 million deaths
nonpoint sources are largely ___________ contributors to water contamination
overlooked
what are nonpoint sources of water pollution
pollutants which run off or seep into waterways from broad areas of land rather than entering the water through a discreet pipe or conduct
if water is treated well, ______________ ___________ such as aeration is needed to remove iron and dissolved gases such as hydrogen sulfide
preliminary treatment
the ______ _____ lowers the pH of the water
sulfuric acid
_________________ ___________ __________________ consist of pesticides, industrial solvents and cleaning fluids, polychlorinated biphenyls and disinfection by-products
synthetic organic pollutants
what does biochemical oxygen demand (BOD) mean
the amount of dissolved oxygen that must be present in water in order for microorganisms to decompose the organic matter in the water, used as a measure of the degree of pollution
where are fallout of airborne pollutants released from
the atmosphere through human activities eventually return to earth and the rivers, lakes or oceans either directly or in runoff
what does acid mine drainage cover
the bottom of streams, smothering the bottom life
in 1972 congress passed what federal amendment that was later modified to the clean water act
the federal water pollution control act amendment
what should drinking water treatment do
theoretically remove all contaminants in the water, or at least reduce them to acceptable levels. All drinking water, regardless of its source, should be treated prior to consumption
what was the original intent of the federal water pollution control act
to allow states to cleanup waterways and determine what their specific function should be -ex: drinking water, swimming, fishing, etc.
what does the clean water act require for each category in industrial discharge
to develop technology standards
why are sewer treatment facilities needed?
to help alleviate the health and aesthetic problems created by dumping raw sewage into waterways
what is the aim of sewage treatment
to improve the quality of wastewater to the point that it can be discharged into a waterway without seriously disrupting the aquatic environment or causing human health problems
in secondary treatment, what are microorganisms used for
to utilize in the presence of an abundant oxygen supply to break down organic materials into inorganic carbon dioxide and minerals
what does sewage sludge contain
toxic chemicals and pathogens -heavy metals such as copper, zinc, lead cadmium, PCBs
what does disinfection mean
treating effluent by adding chlorine prior to discharge in order to eliminate any remaining disease causing organisms
________________ are disinfection by-products, they are formed when chlorine is added to the water containing the naturally occurring humic substances found in any lake or river
trihalomethanes