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TEXAS WASTEWATER CLASS B EXAM 2024
| ALL QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) | LATEST
VERSION | ALREADY GRADED A+
Before entering a manhole the operator should test for ________and oxygen levels and ________the manhole before entering. ------CORRECT ANSWER---------------all hazardous gasses and ventilate When a municipal wastewater effluent has a high nitrate level and low ammonia level this most likely means ------CORRECT ANSWER--------------- the effluent has received a high degree of aerobic treatment Total solids in wastewater are the sum of ------CORRECT ANSWER---------- -----Settleable and volatile solids This treatment device is commonly used to separate and remove large solids from raw wastewater ------CORRECT ANSWER---------------A Mechanically raked bar screen ___________would have an adverse effect on the proper settling of solids in a clarifier. ------CORRECT ANSWER---------------A short circuiting flow pattern This test would give the best information on how efficiently a trickling filter was operating ------CORRECT ANSWER---------------Percent BOD Removal
This trickling filter problem could be reduced by increasing the recirculation ratio ------CORRECT ANSWER---------------Filter files What gases are produced by the controlled anaerobic digestion of wastewater sludge's ------CORRECT ANSWER---------------Methane & Carbon Dioxide These diseases are caused by pathogenic organisms that may be present in raw wastewater ------CORRECT ANSWER---------------Hepatitis, typhoid, paratyphoid,dysentery, cholera, gastroenteritis, polio, hookworm and giardiasis During heavy rain it is possible that manholes and lift stations may overflow, discharge waste materials into roadways or ditches. This type of discharge (SSO) would be ------CORRECT ANSWER--------------- considered an unavoidable discharge, a violation of the Texas Water Code, a bypass that must be reported within 24 hours and considered a health hazard An effective way for the collection system worker to prevent infection by waterborn pathogenic organism is to ------CORRECT ANSWER--------------- Wear protective clothing and avoid direct contact with waste water _________will increase the chances that sewage will turn septic ------ CORRECT ANSWER---------------Stoppages in the main line
In an excavation if a ladder is used as a means of exit, it must extend ________feet above the ground and be secured and within ____ feet laterally of anyone in the excavation. ------CORRECT ANSWER--------------- 3 feet / 25 feet laterally A ____________ would be the best to determine if a storm drain is connected to a sanitary sewer line. ------CORRECT ANSWER--------------- Smoke Test _________ would most commonly be used to seal a number of joint leaks on a main with minimal interruption ------CORRECT ANSWER--------------- internal grouting Pre-treatment of wastewater would include: ------CORRECT ANSWER------- --------Coarse or fine screening, grinding and grit removal and grease removal and pre-aeration Primary treatment of wastewater would include ------CORRECT ANSWER-- -------------settling tanks or basins, scum collection and removal, sludge collection and removal Secondary treatment typically used today would include ------CORRECT ANSWER---------------Stabilization ponds, trickling filters, rotating biological contractors (RBC) & activated sludge
Essential components of the wastewater collection system include ------ CORRECT ANSWER---------------Sewer mains & piping, Lift Stations, Pumps, Grease & Sand traps, & Manholes Grit removal would be considered ------CORRECT ANSWER---------------A part of Primary Treatment The protozoa that causes dysentery would most likely be destroyed by ------ CORRECT ANSWER---------------Disinfection Using final plant effluent in cooling towers would be a ------CORRECT ANSWER---------------Beneficial way to reuse treated effluent TCEQ may authorize discharge of untreated wastewater into or near a receiving stream in extreme cases. This is referred to as ------CORRECT ANSWER---------------Bypass Enforcement action from TCEQ may be taken if pollution or waste violates the Texas Water Code. Violations of Water Code may include ------ CORRECT ANSWER---------------Unauthorized discharge, accidental discharge & health hazard Solids in wastewater are classified as ------CORRECT ANSWER--------------
- Total (TR), Suspended (TSS), Dissolved (TDS), Settleable (SS), Non- setteable, Floatable, Organic and Inorganic
Acute toxicity occurs when ------CORRECT ANSWER---------------There is a rapid die off of treatment organisms Chronic toxicity occurs when ------CORRECT ANSWER---------------Certain microorganisms become inactivated but others continue to work resulting in a sick biological process A mechanical device that screens & cuts large solids in small particles ------ CORRECT ANSWER---------------Cumminuter Detention time in wastewater typically refers to ------CORRECT ANSWER-- -------------The time sewage is kept in a sedimentation basis There are five (5) major components to a trickling filter ------CORRECT ANSWER---------------Filter floor, underdrain, walls, filter media, & distributer arms Zoogleal Mass refers to ------CORRECT ANSWER---------------A thick layer of jelly like slime where organisms bacteria, fungi, protozoa and ciliates thrive. The efficiency of a trickling filter is measured in ------CORRECT ANSWER-- -------------Percent BOD Removed
Common operating problems with a trickling filter include ------CORRECT ANSWER---------------Ponding, Filter files, Odors, Clogging of Nozzles, & Snails Wastewater Stabilization Ponds are an approved process for wastewater treatment. Organic loading of Stabilization Ponds is typically ------ CORRECT ANSWER---------------35 lbs BOD/Acre/Day with a minimum of 30 days detention time Wastewater Stabilization Ponds work through a complex process which includes ------CORRECT ANSWER---------------Sunlight, Oxygen, Nutrients, Algae, and Bacteria Facultative Lagoons have two zones of treatment ------CORRECT ANSWER---------------an aerobic surface layer and an anaerobic bottom layer Typically one could expect ____ % BOD removal in a Facultative Lagoon -- ----CORRECT ANSWER--------------- 50 Aerated Lagoons rely on ______ to provide ____and _____ ------ CORRECT ANSWER---------------Mechanical aeration/ Aeration & mixing The most common method of dewatering and drying sludge is ------ CORRECT ANSWER---------------drying bed
stoppage to avoid _________. ------CORRECT ANSWER---------------Clear or open / Forcing sewage into customer homes or businesses The name of the State Agency responsible for enforcing pollution control laws in Texas ------CORRECT ANSWER---------------Texas Commission of Environmental Quality The term pathogenic means ------CORRECT ANSWER---------------Capable of causing disease The minimum separation between sewer lines and potable water lines is --- ---CORRECT ANSWER---------------9 feet A licensed wastewater operator is a professional ------CORRECT ANSWER---------------consistently does best job possible, practices personal safety, strives to improve job knowledge, strives to keep the plant and collection system in the best appearance and working order An important step in testing a sample for Total Suspended Solids is ------ CORRECT ANSWER---------------Filtering a sample The Biochemical oxygen Demand (BOD) of a sample is based on ------ CORRECT ANSWER---------------Measuring the dissolved oxygen (DO) used
The results of Biochemical Oxygen Demand (BOD) sample taken at a treatment plant tells the operator ------CORRECT ANSWER---------------How the plant was operating 5 days ago Which of the following are dangerous gasses that are likely to be present in lift stations and manholes? ------CORRECT ANSWER---------------Natural gas, gasoline fumes, hydrogen sulfide and carbon dioxide A preferred hydraulic method of cleaning sewer lines is ------CORRECT ANSWER---------------Hydro Jet Cleaner Ways to reduce bad odors coming from a collection system ------CORRECT ANSWER---------------routinely cleaning slow running or low flow lines, adding chlorine or hydrogen peroxide to the collection system Types of pipe that are commonly used in wastewater collection system -----
- CORRECT ANSWER---------------ductile iron, Poly Vinyl Chloride (PVC) Before entering a confined space a worker should ------CORRECT ANSWER---------------Use approved monitoring device and check for the presence of dangerous gasses, ventilate the space with a blower, wear a safety harness and attach a life line A properly designed and operated primary sedimentation tank should remove _____ percent of incoming BOD ------CORRECT ANSWER----------- ---- 30 - 40%
Contributes to the infiltration in a collection system ------CORRECT ANSWER---------------breaks in the main lines, high ground water levels, heavy rains, hydro jet cleaning plugged mains When a centrifuge pump loses prime the ------CORRECT ANSWER---------- -----pump is no longer moving liquid A Rotating Biological Contactor (RBC) is ------CORRECT ANSWER---------- -----fixed firm biological treatment process Needs to be checked regularly to properly operate an activated sludge treatment plant ------CORRECT ANSWER---------------aeration equipment and mixed liquor solids Point source discharges are ------CORRECT ANSWER--------------- discharges that come from pipes or ditches that are monitored, controlled and inspected Non-point discharges are ------CORRECT ANSWER---------------discharges that have intermittent, dispersed flows having little or no control The Texas Water Code establishes the protection of water quality and quantity of the state by ------CORRECT ANSWER---------------setting stream standards, issues permits for discharges, identifies non-point source controls, and establishes water reuse.
The wastewater plant operator is primarily responsible for ------CORRECT ANSWER---------------treating wastewater discharged into the community Chapter ___ of the Texas Water Code is the state law controlling water pollution and ___ authority to control discharges in Texas ------CORRECT ANSWER---------------Chapter 26 and Texas Commission of Environmental Quality The Texas Commission on Environmental Quality can revoke an operator's license if the operator ------CORRECT ANSWER---------------causes permit violation, falsifies records or neglects their duty If accidental discharge, bypass, or spill (SSO) of wastewater occurs the responsible party MUST notify TCEQ regional offices within ____ hours ---- --CORRECT ANSWER--------------- 24 Aerobic Bacteria require_____ in the water for their metabolism ------ CORRECT ANSWER---------------oxygen Anaerobic Bacteria _____ live with O2 present in the water for their metabolism ------CORRECT ANSWER---------------cannot Facultative Bacteria require__________in the water for their metabolism --- ---CORRECT ANSWER---------------either aerobic or anaerobic conditions
Sources of waste water include ------CORRECT ANSWER--------------- domestic, storm water, commercial, food processing, agricultural and industrial A sewer manhole provides access into the system for cleaning or service. A manhole is located ------CORRECT ANSWER---------------at changes in alignment, diameter, grade, direction and intersection New manholes must have an inside diameter of at least ______ feet and the entry access must be at least ____inches. ------CORRECT ANSWER--- ------------4 feet and 24 inches In the past ____ was used to construct manholes. This product is prohibited for construction or grading today ------CORRECT ANSWER------- --------brick and mortar Verified clay and Poly Vinyl Chloride (PVC) are the most common pipe materials used for sewer lines but other materials are available such as -----
- CORRECT ANSWER---------------ductile iron, cast iron, acrylontrile butadiene styrene (ABS) Concrete, polyethylene & asbestos concrete Whenever wastewater cannot flow to the treatment plant by _____ a _____ is typically used ------CORRECT ANSWER---------------gravity/ lift station The primary cause of stoppage in a collection system is _____ and _____ - -----CORRECT ANSWER---------------grease/roots
The _____pump is most commonly used in a lift station ------CORRECT ANSWER---------------centrifugal A centrifugal pump must be ____ or it will not pump ------CORRECT ANSWER---------------primed ______ gas is very toxic and deadens the sense of ______ ------CORRECT ANSWER---------------Hydrogen Sulifide/smell ______ gas is colorless, odorless and heavier than air ------CORRECT ANSWER---------------Methane ______ are the smallest , most numerous, and most important of the activated sludge microorganisms ------CORRECT ANSWER--------------- bacteria Organic loading refers to the pounds per day of ____ per acre feet or 1, cubic feet of filter media ------CORRECT ANSWER---------------BOD Hydraulic loading refers to the volume of ____, including recirculation, applied to the filter ------CORRECT ANSWER---------------water The most common type(s) of trickling filters are- ------CORRECT ANSWER- --------------Standard rate (1-4 mgd) and High Rate (10-40 mgd)
Anaerobic digesters are covered to keep out ____, and to trap useful methane which can be used to keep the digester warm. ------CORRECT ANSWER---------------free oxygen Unstable anareobic sludge contains streaks of _________ or ________. --- ---CORRECT ANSWER---------------gray/green Aerobic digestion is an ____process whereby the aerobic bacteria consume themselves ------CORRECT ANSWER---------------Endogenous Approved disposal methods for digested, dewatered, sludge's are landfill, ____ and ____. ------CORRECT ANSWER---------------Incineration & Land Application Landfill applied sludge must have a solids content of at least _________percent ------CORRECT ANSWER--------------- 20 Calcium Hypochlorite (HTH) is a strong _______ and reacts violently with _________. ------CORRECT ANSWER---------------Oxidizer/Oil & Hydrocarbons When added to water chlorine forms _____&_______acid ------CORRECT ANSWER---------------Hydrochlorous and Hydrochloric
When ammonia is present in wastewater and reacts with chlorine_________are formed ------CORRECT ANSWER--------------- Chloramines Effluent dosage of chlorine in the contact chamber must produce a total combined residual of ------CORRECT ANSWER---------------1.0 mg/L after 20 minutes Besides disinfection, chlorine has other uses at the wastewater treatment plant such as ------CORRECT ANSWER---------------Reduces BOD, Odor, Algae growth, Helps with Grease TCEQ allows the reuse of wastewater, some of these include ------ CORRECT ANSWER---------------Irrigation, aquifer recharge, cooling towers and fire protection All reclaimed water piping must be _______in color ------CORRECT ANSWER---------------purple The Activated Sludge Process can produce a high degree of treatment. Typically one could expect a ______to_______% BOD removal ------ CORRECT ANSWER---------------90 to 99% The Activated Sludge plant has five (5) Critical Components. They are ------ CORRECT ANSWER---------------Oxygen supply, Aeration tanks, Clarifiers, Return & Waste
