Drinking Water

Question 1

How does the California Safe Drinking Water Act (SDWA) guide and regulate drinking water?

Answer 1

Established (1972) To ensure that drinking water is safe, SDWA sets up multiple barriers against pollution. These barriers include: source water protection, treatment, distribution system integrity, and public information. Public water systems are responsible for ensuring that contaminants in tap water do not exceed the standards.

https://www.epa.gov/sites/default/files/2015-04/documents/epa816f04030.pdf

The State Water Resources Control Board was established in 1967 by the Legislature. In 2014, the State Water Board Resources Control Board assumed responsibility for the drinking water regulatory and financial assistance programs previously overseen by the Department of Public Health.

https://www.waterboards.ca.gov/laws_regulations/docs/drinking_water_code_2021.pdf

Question 2

What is the bulletin 74-90 and 74-81 and how does it affect regulation of drinking water?

Answer 2

74 -81 is a Well Water Standards (December 1981) and 74-90 California Well Standards ( June 1991) created by the California Department of Water Resources.

These bulletins are based on the construction, sealing, casing, well development, etc standards for California Regulated water well standards.

Actual Bulletins:

https://archive.org/details/protectwellst7490calirich/page/n13/mode/2up

https://archive.org/details/waterwellstandar7481calirich/page/n1/mode/2up

Question 3

Who has jurisdiction and authority of local construction standards?

Answer 3

The State Water Board is committed to ensuring that all Californians have access to safe, clean, and affordable drinking water. The regulation of the state’s drinking water is primarily the responsibility of the State Water Board. Report to the Legislature in Compliance with the Health and Safety Code Section 116365.

https://calmatters.org/wp-content/uploads/2021/12/Safe-Drinking-Water-Plan-for-California-September-2021.pdf

In 2014, the State Water Board Resources Control Board assumed responsibility for the drinking water regulatory and financial assistance programs previously overseen (delegated) by the Department of Public Health.

Question 4

What are some primary drinking water quality standard factors?

Answer 4

Radioactivity - is expressed in terms of picocuries per liter; 15 (pCi/L) MCL;

Gross alpha particle activity (15)
Gross beta particle activity (4 mrem/yr)
Radium-226 + Radium-228 (5)
Strontium-90 (8)
Uranium (20)

Organic -

Synthetic -Synthetic Organic Compounds (SOCs) are man-made organic compounds that are less volatile, i.e., less likely to escape into the atmosphere; Glyphosate highest MCL of 7 mg/L.

Volatile - Some VOCs (Volatile Organic Compounds) — including benzene, PCE and TCE — can increase your risk for cancer if swallowed, or breathed in large amounts over a long period of time. At very high levels, they can cause damage to the nervous and immune systems and to the kidneys and liver.

Inorganic
Nitrites (1) / Nitrates (10)
Nitrate + Nitrite (as N) (10)
Aluminum (1)
Perchlorate (0.006)
Copper (1.3)
Lead (0.015)

Inorganic heavy metals - Drinking water contaminated with heavy metals namely; arsenic (0.010 )
cadmium (0.005)
nickel (0.1)
mercury (0.002)
chromium (–)
zinc (5)

Biological
Giardia
Cryptosporidium
E. Coli
Salmonella
Shigella
Campylobacter
Hepatitis A and E
Pseudomonas
Entamoeba histolytica
Leptospirosis
Vibrio
Polio

https://calmatters.org/wp-content/uploads/2021/12/Safe-Drinking-Water-Plan-for-California-September-2021.pdf

https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/documents/mclreview/mcls_dlrs_phgs.pdf

Question 5

What are some secondary drinking quality standard factors

Answer 5

Taste - used to find contaminates such as iron and manganese

Odor - issues such as manganese and methyl tertiary butyl ether (MTBE) contamination

Appearence - Yellow, blue, green, or cloudy water, however, can indicate more serious contaminants. High levels of chemicals, metals, or other contaminants could bring about these changes in color.

https://calmatters.org/wp-content/uploads/2021/12/Safe-Drinking-Water-Plan-for-California-September-2021.pdf

Question 6

What defines a public water system

Answer 6

All public water systems must have at least 15
service connections or serve at least 25 people per day for 60 days of the year.

Question 7

Drinking water standards apply to WHICH water systems?

Answer 7

Community Water System (there are approximately 54,000) - A public water system that serves the same people year-round. Most residences including homes, apartments, and condominiums in cities, small towns, and mobile home parks are served by Community Water Systems.

Non-Community Water System - A public water
system that serves the public but does not serve the
same people year-round. There are two types of noncommunity systems:

Non-Transient Non-Community Water System (there
are approximately 20,000) - A noncommunity water
system that serves the same people more than six
months per year, but not year-round, for example,
a school with its own water supply is considered a
non-transient system.

Transient non-community water system (there are
approximately 89,000) - A non-community water
system that serves the public but not the same
individuals for more than six months, for example,
a rest area or campground may be considered a
transient water system.

Question 8

Sample planning for water systems:

SALVADO HAS DETAILS INFO STARTING ON PAGE 287

Answer 8

Water samples are collected as an adjunct to the sanitary survey as an aid in measuring the quality of the raw water and effectiveness of treatment given. Microbiological examinations; chemical, radiochemical, and physical analyses; and microscopic examinations may be made depending on the sources of water, climate, geology, hydrology, waste disposal practices on the watershed, problems likely to be encountered, and purpose to be served. In any case, all samples should be properly collected, transported, and preserved as required, and tests should be made by an approved laboratory in accordance with the procedures provided in the latest edition of Standard Methods for the Examination of Water and Wastewater or as approved by the EPA.

Question 9

Locations for sampling points for water systems

Answer 9

Kimura explains, “ Most sampling containers are 300 milliliters in size. They are usually sterilized plastic containers with a tight fitting leak proof cap. When taking a water sample with the most representation of the entire source. Care must be used not to place fingers or touch the cap needlessly to contaminate the sample reading with the hand’s bacteria. The rule of thumb is to keep the bottle clean and take a representative environmental sample.”

Question 10

Twelve (12) disease agents that contaminate water:

Answer 10

o Giardia
o Cryptosporidium
o E. Coli
o Salmonella
o Shigella
o Campylobacter
o Hepatitis A and E
o Pseudomonas
o Entamoeba histolytica
o Leptospirosis
o Vibrio
o Polio

Question 11

What is cross connection?

Answer 11

A cross connection is any connection or arrangement, physical or otherwise, between a potable water supply system and any plumbing fixture through which it may be possible for non-potable contaminated water to enter any part of the potable water system. (Kimura)

A cross-connection is any physical connection between a potable water system and a nonpotable water supply; any waste pipe, soil pipe, sewer, drain; or any direct or indirect connection between a plumbing fixture or device whereby polluted water or contaminated fluids including gases or substances might enter and flow back into the potable water system.

Question 12

What are some examples of cross connection control?

Answer 12

Backpressure units, air gap separation, vacuum breakers, flushometer, double check valve, reduced pressure backflow prevention devices.

Question 13

What Electromagnetics equipment measures

Answer 13

the difference in conductivity between buried materials such as the boundaries of contaminated plumes or landfills saturated with leachate and uncontaminated materials.

Question 14

Electrical resistivity

Answer 14

the resistance a material offers to the passage
of an electric current between electric probes, which can be interpreted to identify or determine rock, clay and other materials, porosity, and groundwater limits.

Question 15

How do diseases transmit through pollution?

Answer 15

Ground water pollution can lead to various disease infection into the ground water. Discharged cesspool and sewage into the soil, pesticides, soil fumigants, landfills, oil waste, and highway deicing compounds, abandoned oils, and gas well residuals can travel through the ground and contaminate the water sources.

When there is pollution to the ground water, a regulated contaminated would be put on a path to treat the water (system) or bring a better water source.

Question 16

What are some type of diseases that can be transmitted into the water system?

Answer 16

Scabies, skin disease, yaws, trachoma, Shigellosis, Amebiasis, Schistosomiasis, Leptospirosis, Infectious hepatitis, Giardiasis, Typhoid, Paratyphoid Fever, and Dracunculiasis or Guinea Worm disease.

Question 17

What are some water treatment system failures that may cause pollution into the ground water?

Answer 17

Treatment consisting of coagulation, flocculation, sedimentation, rapid sand filtration, and chlorination has little effect on some chemical contaminants

A surface-water supply or an inadequately filtered water supply may
admit into a distribution system organic matter, minerals, and sediment, including fungi, algae, macroscopic organisms, and microscopic organisms. These flow through or settle in the mains or become attached and grow inside the mains when chlorination is marginal or inadequate to destroy them.

Water treatment contaminants article: https://www.ewg.org/research/water-treatment-contaminants

Question 18

American Water Works Association (AWWA) is dedicated to

Answer 18

securing drinking water from the highest quality sources available and protecting those sources to the maximum degree possible.

Public health gets all their standards to incorporate.

Question 19

ground water source

Answer 19

The ground water itself can purify by percolation filtration. Water sinks into the ground and naturally filters as it travels downward (by gravity).

Funfact:The Ground Water Rule (GWR) was signed by the EPA Administrator Stephen L. Johnson on October 11, 2006. EPA published the GWR in the Federal Register on November 08, 2006. The GWR provides protection against microbial pathogens in public water systems using ground water sources.

Question 20

ground water under the influence of surface water

Answer 20

Ground Water Under Direct Influence
- “Under the direct influence of
surface water” means the
groundwater source is located
close enough to nearby surface
water,
-such as a river or lake,
-to receive direct surface water
recharge.
-Since a portion of the groundwater
source’s recharge is from surface
water, the groundwater source is
considered at risk of contamination.
from pathogens such as Giardia
lamblia and viruses, which are not
normally found in true
groundwaters.

Question 21

How much chlorine (bleach) should you use to disinfect the five gallon storage tank?

Answer 21

clear water .5 tsp.
cloudy water 1 tsp

Question 22

Springs source water

WIKIPEDIA

Answer 22

Springs are formed when groundwater flows onto the surface. This typically happens when the water table reaches above the surface level, or if the terrain depresses sharply. Springs may also be formed as a result of karst topography, aquifers or volcanic activity. Springs have also been observed on the ocean floor, spewing warmer, low-salinity water directly into the ocean.

Springs formed as a result of karst topography create karst springs, in which ground water travels through a network of cracks and fissures—openings ranging from intergranular spaces to large caves, later emerging in a spring.

The forcing of the spring to the surface can be the result of a confined aquifer in which the recharge area of the spring water table rests at a higher elevation than that of the outlet. Spring water forced to the surface by elevated sources are artesian wells.

Question 23

Surfacewater as a water source

Answer 23

Quality of surface water depends on the watershed area drained, land use, location, and sources of natural and man-made pollution, and natural agencies of purification, such as sedimentation, sunlight, aeration, nitrification, filtration, and dilution.

heavily polluted surface waters should be avoided as drinking water supplies,

Question 24

Underground storage tanks and their potentialy to contaminate source water

Answer 24

Underground storage tanks (USTs) can contain gasoline, oil, chemicals, or other types or liquids. Over time, the tanks can corrode, crack, and develop leaks, which can cause serious contaminaiton if the contaminaiton leaks out and gets into the groundwater. The Hydrocarbons can dissolve into the groundwater and cause pollution. A lekaing UST can present other health and environmental risks, including the potential for fire and explosion.

Question 25

naturally occuring arsenic, radioactivity and its potentially to contmainate water source.

Arsenic

https://www.who.int/news-room/fact-sheets/detail/arsenic#Overview

Answer 25

Arsenic is naturally present at high levels in the groundwater of several countries. Long-term exposure to arsenic from drinking-water and food can cause cancer and skin lesions. It has also been associated with cardiovascular disease and diabetes. In utero and early childhood exposure has been linked to negative impacts on cognitive development and increased deaths in young adults.

One of the biggest causes of radioactivity in water is natural radioactive decay. Certain elements found in the Earth’s crust, including radium, uranium, and thorium, undergo natural radioactive decay. During this process, radiation is released. If these radioactive elements are located underground, they may contaminate groundwater supplies.

Question 26

Agriculture activities potentialy contamiantion to source water

Answer 26

Excessive use to pesticides and chemcial fetilizers can cause a huge excessive surface water contamiantion during run offs that be peroculate intot he gorund water.

Poorly managed animal feeding operations
Overgrazing
Overworking the land (for example, plowing too often)
Poorly managed and ineffective application of pesticides, irrigation water, and fertilizer

Question 27

Sewage disposal systems

Answer 27

Septic systems can contribute to source water contamination for various reasons, including improper siting, poor design, faulty construction, and incorrect operation and maintenance. Most States and localities regulate siting, design, and construction of septic systems and only regulate operation and maintenance for large capacity septic systems.

Question 28

mining activites and its potentially to contmainate water source

Answer 28

Mining affects fresh water through heavy use of water in processing ore, and through water pollution from discharged mine effluent and seepage from tailings and waste rock impoundments. Increasingly, human activities such as mining threaten the water sources on which we all depend.

Question 29

solid waste disposal sites and its potentially to contmainate water source

Answer 29

The solid waste disposal affects the quality of water as it leaches down in deeper layers of water bodies having dissolved organic and inorganic constituents from solid waste. The resulting polluted liquid, popularly known as leachate, increases in its concentration levels when it seeps deep inside and appears brownish to black in colour with a rotten smell. It has more organic pollutants with ammoniacal nitrogen.

Question 30

industrial activites and its potentially to contmainate water source

Answer 30

Industries affect large amounts of water, both through consumption and contamination, for purposes including: Chemical processing Resource production and harvesting Waste disposal These processes consume and contaminate water on mass scales when not properly managed, leading to millions lacking access to clean drinking water.

Question 31

What is cross connection control

Answer 31

The goal is to have no connection between a water of drinking water quality
(potable) and an unsafe or questionable (nonpotable) water system or between
a potable system and any plumbing, fixture, or device whereby nonpotable
water might flow into the potable water system.

Question 32

Levels of hazards determine control devices

Answer 32

Sometimes determining hazard level is as easy as considering what will be present in the line that needs protection. In general, irrigation systems are high hazard and require an RPZ device. Irrigation systems can come into contact with fertilizer, pesticides, and feces. Various types of equipment come with specific risks so certain devices are paired with them based on their hazard level. Beverage dispensers typically have dual checks, dishwashers mostly use atmospheric vacuum breakers, and lavatories are often paired with air gaps.

Low hazards are called pollutants, and do not pose a health hazard while high hazards are considered contaminants and would pose a health hazard. The most commonly referred to backflow devices are double check backflow valves and reduced pressure zone devices.

Any building that uses materials which would pose a health threat- contaminants - requires a backflow device suited for high hazards. There are some obvious buildings which come to mind such as chemical plants, manufacturing plants, and oil and gas production warehouses

Question 33

Backflow prevention devices

Answer 33

Are cross connection controls that prevent reversal flow of water from intended direction in any pipe or plumbing system.

Question 34

Check valve

video

https://www.youtube.com/watch?v=r0mpimH5hc4

Answer 34

is a valve that normally allows fluid to flow through it in only one direction.
An air chamber, surge tank, or similar water-hammer
suppression device should be installed just beyond the check valve, particularly on long pipelines or when pumping against a high head.

Question 35

Chlorine test kit

Answer 35

In general, the analyst will need to measure out a known volume of sample using a test tube or flask provided with the kit and will need to add the DPD reagents in the order described, wait a specific reaction time, and then measure the pink color that
develops in the sample. The intensity of the pink color that develops after the addition of a reagent is measured using a spectrophotometer or a color comparator and relates directly to the amount of disinfection residual present in the sample.

https://www.epa.gov/sites/default/files/2015-11/documents/drinking_water_sample_collection.pdf

Question 36

pH meter and pH paper

Answer 36

Are tools utilized to test the potential hydrogen levels within the water.
The pH shall not be depressed below 6.5 nor raised above 8.5 for waters that have the following designated uses: municipal and domestic supply, agricultural supply, water contact recreation, and non-contact water recreation.

https://www.waterboards.ca.gov/water_issues/programs/swamp/docs/cwt/guidance/3140en.pdf

Question 37

Total dissolved solids (TDS) Meter

Answer 37

The TDS meter measures the conductivity and converts it into a TDS reading, usually displayed in parts per million (ppm) or milligrams per liter (mg/L).

Question 38

Turbidity Meter

Answer 38

Turbidity Meters technically known as nephelometers – emit light and measure the amount scattered by particles in the sample. The units depend on the wavelength of the light and the angle of the detector(s)13; the most common units are Nephelometric Turbidity Units (NTU) or Formazin Nephelometric Units (FNU).

Research shows drinking water levels can vary in the state of california from 0.1 NTU to 100 NTU. Basically going off percent of the whole body of water…

https://www.waterboards.ca.gov/water_issues/programs/swamp/docs/cwt/guidance/3150en.pdf

Question 39

Sterile Sample Bottles

Answer 39

Sterile sample bottle used for the detection of coliforms and other microorganisms. Sample bottles conform to EPA standards for sterility, volume, graduation accuracy, and non-autoflourescence.

Question 40

Sampling techniques: Identify good sampling tap

Answer 40

Ideally getting the sample tap that is closest to the water irrigation, for example: Sample the last water spigot from a water treatment facility or upstream of where a water is pumps to a field.

Sample faucets are used to collect water samples to test drinking water for contaminants such as coliform bacteria, nitrate, arsenic, other metals or agricultural chemicals. The proper product design, installation and use of sample faucets are important to ensure reliable sample results.

Question 41

Sampling techniques: Proper Handling of Sample

Answer 41

Obtain proper sampling bottle, properly wash your hands, donning clean gloves, clean surfaces of the sampling area, and ensure to purdge at a high flow of water prior to sampling.

Collecting the Sample: The water sample must be collected within six hours of purging, and usually is collected immediately after purging. If an adjustable-speed pump is used, the pumping rate is
lowered prior to sampling to avoid degassing or aeration of the water sample. Similarly, a faucet or valve should be turned down after purging such that the water will flow slowly and without aeration. Before the sample containers are filled, they should be properly labeled. A sample is collected directly from the bailer, pump discharge, faucet, or valve. The sampling container should be completely filled, and then capped (do not touch the insid eof cap) and properly stored. Finally, the sample log should be completed and all locking covers, locks, and housing covers should be secured safely to ensure protection of the well.

Preserving the Sample: Since water samples are not immediately analyzed in the field, they typically require preservation. Proper preservation ensures that the water quality of the sample does not
change between the time of collection in the field and the time of analysis in the laboratory. Preservation methods suppress chemical reactions that can occur in sample water due to degassing (lower partial pressure of dissolved oxygen, carbon dioxide, etc.) or to exposure to heat and light. Which preservation method is best suited to a given sample depends on the water quality parameters to be measured and the amount of time between collection and analysis. If a water sample is analyzed
for multiple parameters that require different preservation methods, it may be necessary to take several samples using separate containers. Preservation usually also includes cooling the sample to 4°C (40°F). Samples must remain cool during shipping and storage. It is best to deliver the samples to the laboratory within one to two days of sampling. If samples are shipped, the sealed sample containers are put into ice chests that are then packed with ice and transported to the analytical laboratory by express delivery service. At the laboratory, the samples are logged in, given sample ID numbers, and kept cool until they can be analyzed.

Question 42

What is the purpose of sodium thiosulfate in sampling water?

Answer 42

Sodium thiosulfate is a dechlorinating agent that neutralizes any residual halogen and prevents continuation of bactericidal action during sample transit. This should be utilized for water samples submitted for microbiological analyses only.

Question 43

Obtaining a representative sample for water

Answer 43

Samples must be taken from locations that are representative of the water and when selecting sampling points, each locality should be considered individually and the following general criteria are suggested guidelines: (i) the sampling points should be selected such that the samples taken are representative of the source from which water is obtained, (ii) the sampling points should include those that yield samples representative of the conditions at the water system, particularly points of possible contamination, (iii) the sampling points should be uniformly distributed throughout a water system, and (iv) the sampling points chosen should generally yield samples that are representative of the system as a whole.

https://www.sciencedirect.com/topics/earth-and-planetary-sciences/water-sampling#:~:text=Samples%20must%20be%20taken%20from,taken%20are%20representative%20of%20the

Question 44

Membrane Filter Test Advantages/ Disadvantages

Answer 44

Pro: The test is portable and results can be received in a short time than the most probable number method.

Con: The non-fecal coliforms can start growing after the 22 hour incubation period and turbid water samples may clog the membrane filter.

Question 45

Multiple tube Fermentation Test Advantage and disadvantage

Answer 45

Con: It is important to keep in mind that MPN tables are probability calculations and inherently have poor precision. They include a 23% positive bias that generally results in high value. The precision of the MPN can be improved by increasing the number of sample portions examined and the number of samples analyzed from the same sampling point.

https://www.epa.gov/sites/default/files/2015-12/documents/9131.pdf

Pro: One of the most useful applications of MPN is to estimate coliform bacteria and Escherichia coli in water quality tests and screening, in particular, in drinking water. The presence of E. coli in water is indicative of recent fecal contamination.

Question 46

Coli-alert Test Advantages/ Disadvantages

Answer 46

Pro: significantly reduce both false positive and false negative results and provide operators with results that are accurate, non-subjective and require no further confirmation steps.

Con: lengthy incubation times (up to 96 h for confirmation), potential interference by heterotrophic plate count (HPC) bacteria and difficulties in interpreting results

Question 47

What are the physical examinations conducted for water quality?

Answer 47

Odor - odor should be absent or very faint for water to be acceptable, less than 3 threshold odor number (TON).
Taste - The taste of water should not be objectionable; otherwise, the consumer will resort to other sources of water that might not be of satisfactory sanitary quality. Algae, decomposing organic matter, dissolved gases, high concentrations of sulfates, chlorides, and iron, or industrial wastes may cause tastes and odors
Turbidity - is due to suspended material such as clay, silt, or organic and inorganic materials. Enhanced surface-water regulations in the United States require that the maximum contaminant level for turbidity not exceed 0.5 NTU in 95% of the samples taken every month and must never exceed 1 NTU.
Color - should be less than 15 true color units* (sample is first filtered), although persons accustomed to clear water may notice a color of only 5 units. The goal is less than 3 units. Water for industrial uses should generally have a color of 5 to 10 or less.
Temperature - High water temperatures accelerate the growth
of nuisance organisms, and taste and odor problems are intensified. Low temperatures somewhat decrease the disinfection efficiency. Generally in the temperature range of 50 to 60 F (10–16 C)

Question 48

What is the purpose of the Surface Water Treatment Rules (SWTRs)?

Answer 48

The purpose of the Surface Water Treatment Rules (SWTRs) is to reduce illnesses caused by pathogens in drinking water. The disease-causing pathogens include Legionella, Giardia lamblia, and Cryptosporidium.

The SWTRs require water systems to filter and disinfect surface water sources. Some water systems are allowed to use disinfection only for surface water sources that meet criteria for water quality and watershed protection.

Question 49

Drinking water Surface Water Treatment Rules applying to surface water and ground water

Answer 49

Applies to all public water systems (PWSs) using surface water sources or ground water sources under the direct influence of surface water (GWUDI). Requires most water systems to filter and disinfect water from surface water sources or GWUDI.

Establishes maximum contaminant level goals (MCLGs) for viruses, bacteria and Giardia lamblia. Includes treatment technique (TT) requirements for filtered and unfiltered systems to protect against adverse health effects of exposure to pathogens.

Question 50

Drinking water Surface water treatment rules have removal of specific microbes by 2-,3-, and 4-, logs

Answer 50

Chemical filtration through coagulation and removing by the 99%, 999%, 9999% of Cryptosporium, giardia, and virus (note: removal of other bacteria are conducted within the process).

By conducting regular treatment you will be referencing different contact times depending on the log credit provided by that water treatment.

Question 51

Drinking water Surface water treatment rules for monitoring of turbidity

Answer 51

Turbidity can vary both horizontally and vertically in a
waterbody. Water samples should, therefore, be taken at
regular increments across a waterbody and at various
depths (or depth integrated, which is a sample that
represents the entire water column).

In drinking water, particles can interfere with disinfection
by physically blocking UV rays from reaching
microorganisms. Some microorganisms can make
people sick if they occur in drinking water.

https://www.epa.gov/system/files/documents/2021-07/parameter-factsheet_turbidity.pdf

The frequency of CFE turbidity monitoring depends on the system size and type of filtration:
All Systems - Turbidity must be monitored on representative samples of the CFE every 4 hours that the system serves water to the public.

A public water system can substitute continuous CFE turbidity monitoring for 4-hour grab samples. You must record the current CFE turbidity value at equal intervals of 4 hours. Averaging of 4 hours of data, or monitoring at any other intervals longer than
4 hours, is not permitted, except as discussed below.
Systems serving populations < 500
If approved by EPA, they have the option of reducing CFE turbidity monitoring frequency to one per day regardless of the type of treatment.

https://www.epa.gov/sites/default/files/documents/SWTR_Fact_Sheet.pdf

Question 52

Drinking water treatment processes surface water treatment rule for watershed protection

What’s watershed:

https://youtu.be/QOrVotzBNto?si=NkqzV2t1fiS9eXy6

What does watershed proteciton do:

https://www.youtube.com/watch?v=UMBHBygH93s

Answer 52

Watersheds are the LAND area that drains to a water body. We all live in a watershed. Streams, lakes, rivers, and other waters are interconnected with the landscape and all its activities through their watersheds.
Health of clean water is dependent to condition of their surrounding watershed.

Example : Rainbow trout habitat loss from warmer water temperatures associated with climate change already has been observed in the southern Appalachians (Flebbe et al., 2006)

EPA created Healthy Watersheds Program (HWP) to support partners in their efforts to identify, assess, and protect watershed health through the CWA programs aiming to address:
-emerging water quality problems
-loss and fragmentation of aquatic habitat
-altered water flow and availability
-invasive species, and climate change.

Question 53

What are the General principles of treatment or water?

Answer 53

Coagulation
Flocculation
Sedimentation
Filtration
Disinfection

Question 54

Deinfe or decribe Coagulation

Answer 54

Coagulation is often the first step in water treatment. During coagulation, chemicals with a positive charge are added to the water. The positive charge neutralizes the negative charge of dirt and other dissolved particles in the water. When this occurs, the particles bind with the chemicals to form slightly larger particles. Common chemicals used in this step include specific types of salts, aluminum, or iron.

Types:

-Alum - most common aluminum salt used for coagulation is aluminum sulfate, or alum. Used to enlarge the size of the impurities so that they settle down in the sedimentation tanks. Effective in killing pathogens present in the water.
-Synthetic cationic polymers offer several advantages as coagulants compared to the tri- and divalent inorganic counter parts that work mainly through the sweep floc mechanism. First, they neither require strict pH control nor consume alkalinity and, hence, could be used for treating a wider variety of water
-pH dependent various optimal pH ranges are required for coagulation of specific impurities and their mixtures. For natural organic matter of both humic and algogenic origin, acidic pH values are favourable for their removal through charge neutralization mechanism. Algal cells are effectively coagulated at slightly acidic to neutral pH values due to interactions with coagulant hydroxide precipitates. Inorganic particles are eliminated preferably at around neutral pH values. When mixtures of impurities are coagulated, mutual interaction between the impurities may impact dose of coagulant and also optimal pH ranges.

Simple Definition: the action or process of a liquid, especially blood, changing to a solid or semi-solid state.

Question 55

Define or describe Flocculation

Answer 55

Flocculation follows the coagulation step. Flocculation is the gentle mixing of the water to form larger, heavier particles called flocs. Often, water treatment plants will add additional chemicals during this step to help the flocs form.

Simple Definition: “a process of contact and adhesion whereby the particles of a dispersion form larger-size clusters.”

Question 56

Define or describe Sedimentation

Answer 56

Sedimentation is one of the steps water treatment plants use to separate out solids from the water. During sedimentation, flocs settle to the bottom of the water because they are heavier than water.

Simple Definition: the process of settling or being deposited as a sediment.

Question 57

Define or describe Filtration

Answer 57

Once the flocs have settled to the bottom of the water, the clear water on top is filtered to separate additional solids from the water. During filtration, the clear water passes through filters that have different pore sizes and are made of different materials (such as sand, gravel, and charcoal). These filters remove dissolved particles and germs, such as dust, chemicals, parasites, bacteria, and viruses. Activated carbon filters also remove any bad odors.

Water treatment plants can use a process called ultrafiltration in addition to or instead of traditional filtration. During ultrafiltration, the water goes through a filter membrane with very small pores. This filter only lets through water and other small molecules (such as salts and tiny, charged molecules).

Simple Definition: The process in which solid particles in a liquid or gaseous fluid are removed by the use of a filter medium that permits the fluid to pass through but retains the solid particles. Either the clarified fluid or the solid particles removed from the fluid may be the desired product.

Question 58

Define or Describe Disinfection

https://www.cdc.gov/healthywater/drinking/public/water_treatment.html#:~:text=Public%20drinking%20water%20systems%20use,sedimentation%2C%20filtration%2C%20and%20disinfection.

Answer 58

After the water has been filtered, water treatment plants may add one or more chemical disinfectants (such as chlorine, chloramine, or chlorine dioxide) to kill any remaining parasites, bacteria, or viruses. To help keep water safe as it travels to homes and businesses, water treatment plants will make sure the water has low levels of the chemical disinfectant when it leaves the treatment plant. This remaining disinfectant kills germs living in the pipes between the water treatment plant and your tap.

In addition to or instead of adding chlorine, chloramine, or chlorine dioxide, water treatment plants can also disinfect water using ultraviolet (UV) light pdf icon[PDF – 7 pages]external icon or ozone pdf icon[PDF – 7 pages]external icon. UV light and ozone work well to disinfect water in the treatment plant, but these disinfection methods do not continue killing germs as water travels through the pipes between the treatment plant and your tap.

Simple Definition: Describes a process that eliminates many or all pathogenic microorganisms, except bacterial spores, on inanimate objects.

Question 59

What are some types of filtration?

Answer 59

Slow Sand Filtration - The process percolates untreated water slowly through a bed of porous sand, with the influent water introduced over the surface of the filter, and then drained from the bottom.
Rapid Sand Filters - use coarse sand as a filtration medium to remove fine suspended solids from water with varying levels of turbidity (or ‘muddiness’).
Granular media filters - may consist of pressure sand, anthracite coal, or diatomaceous earth, granite activated carbon. This mfiltration works under pressure or vaccum, best for waters of <10 NTU, have smaller footprint, no chemicals added.
Bag Filters - uses a bag manufactured from filtering material. The bag sits inside the filter housing and as it fills up, the water passes through the tiny holes in the material and leaves behind unwanted particles. These systems are quick and easy to use, cost-effective and easy to maintain.
Reverse osmosis external icon is another filtration method that removes additional particles from water. Water treatment plants often use reverse osmosis when treating recycled waterexternal icon (also called reused water) or salt water for drinking.

Question 60

What is combined and Free chlorine residual?

Answer 60

The amount of chlorine that has reacted with nitrates and is unavailable for disinfection which is called combined chlorine
The free chlorine, which is the chlorine available to
inactivate disease-causing organisms, and thus a measure to determine the potability of water.

Question 61

Breakpoint chlorination

Answer 61

This is the point where all the cloramines has been binded and as the concentration of chlorine increases free chlorine becomes available

Question 62

pH - chlroine relationship

Answer 62

Chlorine levels are pH dependent because the higher pH the higher the hypochlorite ion produced. Hyperchlorous acid (HOCL) is the best chlorine disinfectant and present as pH is raising.

Question 63

disinfection byproducts

Answer 63

Bromate
Chlorite
Haloacetic acids (HAA5)
Total trihalomethanes (TTHMs)

Question 64

General principle of ozone treatment

file:///C:/Users/j4922/Downloads/ozon.pdf

Answer 64

Ozone is produced when oxygen (O2) molecules are
dissociated by an energy source into oxygen atoms
and subsequently collide with an oxygen molecule to
form an unstable gas, ozone (O3), which is used to
disinfect wastewater. Most wastewater treatment
plants generate ozone by imposing a high voltage
alternating current (6 to 20 kilovolts) across a
dielectric discharge gap that contains an
oxygen-bearing gas. Ozone is generated onsite
because it is unstable and decomposes to elemental
oxygen in a short amount of time after generation.
Ozone is a very strong oxidant and virucide.

The mechanisms of disinfection using ozone include:
* Direct oxidation/destruction of the cell wall
with leakage of cellular constituents outside
of the cell.
* Reactions with radical by-products of ozone
decomposition.
* Damage to the constituents of the nucleic
acids (purines and pyrimidines)

Question 65

General principle of ultraviolet light treatment

Answer 65

As a water treatment technique, UV is known to be an effective disinfectant due to its strong germicidal (inactivating) ability; UV is energetic enough (ionizing radiation) that it can break chemical bonds, killing microbes. UV disinfects water containing bacteria and viruses and can be effective against protozoans like Giardia lamblia cysts or Cryptosporidium oocysts.

Question 66

Concentration and time for water treatment

Answer 66

Concentration of disinfection residual at the end of the disinfection section (mg/l).

Time of disinfection contact is the time that the disinfectant is in contact with the water from points of application to point of residual measurements (minutes).

CT ensures adequate Giardia and Virus inactivaton

Question 67

pH factor for water treatment

Answer 67

Disinfectant increase and pH decreases because you gain more hypochloric acid.

Question 68

Temperature factor for water treatment

Answer 68

Disinfection decreases as water temperature decreases because chemical reactions are slow in cold water.

Question 69

Turbidity factor in water treament

Answer 69

Turbidity or suspended particles in the water impacts disinfection; giving high turbidity waters a high disinfection demand.

Question 70

Well construction based on bulletin 74 guidlines

Answer 70

All wells shall be located an adequate location from building and structures allowing access for maintainence, modification, repair, and destruction, unless approved by enforcemnent agencies.

Shall be located a horizontal DISTANCE from the follow:
-Sewer lines (50 feet)
-septic tank or subsurface sewage leaching field (100 feet)
-cesspool or seewpage pit (150 feet)
-animal or fowl enclosure (100 feet)

The well shall be located up the ground water GRADIENT (higher / adjacent ground from potential pollution).

Well shall be located outside areas of flooding levels, drainage, or runoffs. Top of the well casing shall terminate above grade. Surface drainage shall be redirected; well surrounding area build up may be necessary.

Question 71

Annular seal placement for water wells

Answer 71

This seal has a goal to prevent contamination and hold drop pipe. It sits on top of casing and it’s anatomy usually consist of the following; top plate, lip, casing, rubber seal, and bottom plate.

Minimum depth of the annular surface seal must extend below the ground surface as follows;
50 feet - community water supply anf industrial
20 feet - individual domestic, agricultural, air-conditioning, and all other types.

-Placement of the seal shallbe free from loose cutting or other obstructions from annular space before placement.
-Equipped with centering guides or ‘centralizers’ to ensure the two (2) inch minimum radial thickness of seal is maintained. Centralizer material an be of Metal, plastic, other non-degradable material; not wood.
-Preventative infiltration between cement sealing and filter pack, a transition seal (5’ length) material usually bentonite is placed in the annular space, and with a short interval of fine-grained sand.
-Granular siz of bentonite influence location setting; Fine sized (granular or powder) placed above water levels and coarse forms (pallets or chips) are placed below water levels
-annular spacing shall be sealed as soon as practical after completion of driling. The annular space shall not be left unsealed longer than 14 days following the installation of casing.
-ensure proper ground water flow pressure, verify volume of seal to exceed or equals volume to be sealed, and for pressure for placements of sealing material shall be maintained long enoguh for cemet-based sealing material to properly set.

Question 72

Casing for well construction

Answer 72

Well Casing is the tube-shaped structure placed in the well to maintain the well opening from the target ground water to the surface. Along with grout, the casing keeps dirt and excess water out of the well.

Question 73

Packing for well construction

Answer 73

A gravel pack is simply a downhole filter designed to prevent the production of unwanted formation sand.

Question 74

pump curves for well construction

Answer 74

Reading a pump curve will tell you how a pump will perform in regards to pressure head and flow. A pump composite curve cover will include the pump performance curves, horsepower curves, and NPSH required. A curve is defined for a specific operating speed (rpm) and a specific inlet/outlet diameter.

• A pump curve is a graphical
  representation of the performance
  characteristics of a pump.
• A pump curve provides a wealth of
  information regarding the performance
  capabilities of a pump. Information is
  plotted on an x-y graph where the x-axis
  is measured in units of flow and the y-axis
  is measured in units of head, power, and
  NPSHr.

Question 75

cone of depression for well construction

Answer 75

Cone of Depression
Pumping from a well in a water table aquifer lowers the water table near the well. This area is known as a cone of depression. The land area above a cone of depression is call the area of influence.

Question 76

Well head above ground feature

Answer 76

The wellhead is constructed of industrial-strength PVC and has a cap to keep the pipe clear of debris. Your well head should be annually inspected for cracks, damage, and leaks, to keep well water clean and pumps flowing smoothly. If you notice anything strange around your well head, call an expert for advice.

Question 77

sample tap for above ground features

Answer 77

Sample faucets shall be 12 inches above the floor and have a downturned spout in a sanitary area of any water treatment equipment for collection of water samples directly from the well. There are some limited exceptions.

Raw water sampling taps help to identify the problem area when a water sample tests positive for bacteria. Under the Ground Water Rule, a raw water sampling tap is required for existing water systems using groundwater if a positive bacteria sample occurs.

Question 78

Electrical connections for above ground features

Answer 78

Water is a conductor of electricity, and if it comes into contact with live wires, it can cause a short circuit or even lead to electric shock or fires. It’s important to ensure that electrical wiring and components are properly insulated and protected from moisture to prevent these dangers.????

Question 79

Pitless adaptor for well construction

Answer 79

Pitless wells are constructed with the casing extending above ground surface, but the pump discharge pipe is installed below ground surface using a pitless adaptor. A pitless adaptor is a relatively new introduction into well construction and eliminates the need for pit wells and the hazards they can introduce.

Question 80

Drilling methods

Answer 80

Air Rotary Drilling Method. …
Bucket Auger Drilling Method. …
Cable Tool Drilling Method. …
Down the Hole Drilling Method. …
Reverse Circulation Drilling Method. …
Mud Rotary Drilling Method.

There are two main motorised drilling techniques: cable tool percussion (also known as shell and auger); and rotary drilling. Rotary is the most common method used for water borehole drilling. Rotary drilling can be air flush, sometimes with down-the-hole hammer; mud flush; or reverse circulation.

Question 81

Siting considerations for geological formations

Answer 81

A geologic setting shall exhibit an appropriate combination of the conditions specified in paragraph (b) of this section so that, together with the engineered barriers system, the favorable conditions present are sufficient to provide reasonable assurance that the performance objectives relating to isolation of the waste will be met.

https://www.nrc.gov/reading-rm/doc-collections/cfr/part060/part060-0122.html

There are four main types of geological formations: faults, folds, unconformities, and plutons. Faults are cracks in the Earth’s surface. Folds are when rocks are bent or broken. Unconformities are gaps in the rock record.

Question 82

Surrounding activities for siting considerations

Answer 82

If a well is located far enough away from a latrine, the soil is able to filter out harmful organisms before they reach the well. To determine the minimum safe separation distance between latrine and well we need to know three things:

1. Direction the groundwater is moving.
2. Distance between the bottom of the latrine and the water table.
3. Type of soil between the bottom of the latrine and the water table.

Following these guidelines (or any well site placement guidelines) will not guarantee that a well will be free from bacterial contamination. The well must also be properly constructed and the well water tested to assure the best possible water quality.

Question 83

Topography for siting considerations

Answer 83

But, groundwater in an unconfined aquifer tends to flow in the direction that the ground slopes, and it flows from a recharge area to a discharge point. Knowing this, it will usually be better to locate a well uphill from a latrine than downhill from one.

Question 84

Property lines

Answer 84

Generally, well drilling should take place a minimum of 10 feet away from your neighbor’s property. Preferably, the radius should be at least 25 feet. Some jurisdictions may call for a minimum zone of protection of 50 or 75 feet from property lines or septic systems.

Question 85

History of water agency and laws

Answer 85

Federal Water code created in (1948/1949)

State Water Regional Control Board was established (1962)

Environmental Protection Agency (1970)

California Safe Drinking Water Act and Bulletin 74-1 (1972)

Revised bulletin 74-81 (1981)

Revised bulletin 74-90 (1990)