Texas Wastewater Class B Exam {Latest 2024 Update} Questions with Correct Answers, Exams of Law

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Texas Wastewater Class B Exam {Latest 2024 Update} Questions with Correct Answers The name of the State Agency responsible for enforcing pollution control laws in Texas - Answer - Texas Commission of Environmental Quality The term pathogenic means - Answer - Capable of causing disease The minimum separation between sewer lines and potable water lines is - Answer - 9 feet A licensed wastewater operator is a professional - 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 - Answer - Filtering a sample The Biochemical oxygen Demand (BOD) of a sample is based on - Answer - Measuring the dissolved oxygen (DO) used The results of Biochemical Oxygen Demand (BOD) sample taken at a treatment plant tells the operator - 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? - Answer - Natural gas, gasoline fumes, hydrogen sulfide and carbon dioxide A preferred hydraulic method of cleaning sewer lines is - Answer - Hydro Jet Cleaner Ways to reduce bad odors coming from a collection system - 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 - Answer - ductile iron, Poly Vinyl Chloride (PVC) Before entering a confined space a worker should - 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 - Answer - 30-40% Devices that may be used to determine the level of sewage in a lift station - Answer - air bubbler, floats, electrodes, Acoustic (sonic) What is the most important role of aerobic bacteria in the treatment of wastewater? - Answer - decompose organic matter The hydraulic loading of a trickling filter may be determined by - Answer - flow rate and filter area These can be used to dewater sludge - Answer - belt press, drying beds, solid bowl centrifuge, gravity thickener Most important to providing adequate sewage treatment in a stabilization pond - Answer - sunlight, algae, bacteria and time Offensive and objectionable odors which sometimes occur in trickling filters usually indicate - Answer - septic conditions are present Dissolved Oxygen (DO) in aeration tank of an activated sludge plant should be maintained at or about - Answer - 2 to 4 mg/L Contributes to the infiltration in a collection system - Answer - breaks in the main lines, high ground water levels, heavy rains, hydro jet cleaning plugged mains When a centrifuge pump loses prime the - Answer - pump is no longer moving liquid A Rotating Biological Contactor (RBC) is - Answer - fixed firm biological treatment process Needs to be checked regularly to properly operate an activated sludge treatment plant - Answer - aeration equipment and mixed liquor solids The majority of Dissolved Oxygen in raw sewage comes from - Answer - Potable Drinking Water Each person contributes approximately lbs of BOD to the system daily. - Answer - 0.17 Sources of waste water include - 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 - 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. - Answer - 4 feet and 24 inches In the past was used to construct manholes. This product is prohibited for construction or grading today - 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 - 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 - Answer - gravity/ lift station The primary cause of stoppage in a collection system is and - Answer - grease/roots The pump is most commonly used in a lift station - Answer - centrifugal A centrifugal pump must be or it will not pump - Answer - primed gas is very toxic and deadens the sense of - Answer - Hydrogen Sulifide/smell gas is colorless, odorless and heavier than air - Answer - Methane are the smallest , most numerous, and most important of the activated sludge microorganisms - Answer - bacteria Organic loading refers to the pounds per day of per acre feet or 1,000 cubic feet of filter media - Answer - BOD Hydraulic loading refers to the volume of , including recirculation, applied to the filter - Answer - water Unstable anareobic sludge contains streaks of or . - Answer Calcium Hypochlorite (HTH) is a strong and reacts violently with . The most common type(s) of trickling filters are- - Answer - Standard rate (1-4 mgd) and High Rate (10-40 mgd) Odors occur when treatment becomes - Answer - anaerobic gas is greenish-yellow, pungent, heaver than air and highly toxic - Answer - chlorine One common type of weir design for measuring flow is - Answer - V-Knotch Inflow and Infiltration (I&I) typically refers to - Answer - unaccounted for water in the system after heavy rains If the loading on the plant is high, the operator would need to Dissolved Oxygen (DO) levels. - Answer - Organic/Increase A simple method for indicating when to waste sludge is - Answer - 30 minute settling test Organic loading of a stabilization pond is about pounds of BOD/acre/day with a detention time of at leastdays. - Answer - 35 BOD/ 30 Days Anaerobic digesters are covered to keep out , and to trap useful methane which can be used to keep the digester warm. - Answer - free oxygen gray/green Aerobic digestion is an process whereby the aerobic bacteria consume themselves - Answer - Endogenous Approved disposal methods for digested, dewatered, sludge's are landfill, and . - Answer - Incineration & Land Application Landfill applied sludge must have a solids content of at least percent - Answer - 20 Answer - Oxidizer/Oil & Hydrocarbons When added to water chlorine forms & acid - Answer - Hydrochlorous and Hydrochloric When ammonia is present in wastewater and reacts with chlorine are formed - Answer - Chloramines Before entering a manhole the operator should test for and oxygen levels and Effluent dosage of chlorine in the contact chamber must produce a total combined residual of - Answer - 1.0 mg/L after 20 minutes Besides disinfection, chlorine has other uses at the wastewater treatment plant such as - Answer - Reduces BOD, Odor, Algae growth, Helps with Grease TCEQ allows the reuse of wastewater, some of these include - Answer - Irrigation, aquifer recharge, cooling towers and fire protection All reclaimed water piping must be in color - Answer - purple When a municipal wastewater effluent has a high nitrate level and low ammonia level this most likely means - Answer - the effluent has received a high degree of aerobic treatment Total solids in wastewater are the sum of - Answer - Settleable and volatile solids This treatment device is commonly used to separate and remove large solids from raw wastewater - Answer - A Mechanically raked bar screen would have an adverse effect on the proper settling of solids in a clarifier. - Answer - A short circuiting flow pattern This test would give the best information on how efficiently a trickling filter was operating - Answer - Percent BOD Removal This trickling filter problem could be reduced by increasing the recirculation ratio - Answer - Filter files What gases are produced by the controlled anaerobic digestion of wastewater sludge's - Answer - Methane & Carbon Dioxide These diseases are caused by pathogenic organisms that may be present in raw wastewater - 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 - 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 Digester gas typically contains about % - Answer - 65-75% Chronic toxicity occurs when - 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 - Answer - Cumminuter Detention time in wastewater typically refers to - Answer - The time sewage is kept in a sedimentation basis There are five (5) major components to a trickling filter - Answer - Filter floor, underdrain, walls, filter media, & distributer arms Zoogleal Mass refers to - 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 - Answer - Percent BOD Removed Common operating problems with a trickling filter include - 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 - Answer - 35 lbs BOD/Acre/Day with a minimum of 30 days detention time Wastewater Stabilization Ponds work through a complex process which includes - Answer - Sunlight, Oxygen, Nutrients, Algae, and Bacteria Facultative Lagoons have two zones of treatment - Answer - an aerobic surface layer and an anaerobic bottom layer Typically one could expect % BOD removal in a Facultative Lagoon - Answer - 50 Aerated Lagoons rely on to provide and - Answer - Mechanical aeration/ Aeration & mixing The most common method of dewatering and drying sludge is - Answer - drying bed The depth of sludge drawn to a drying bed should be - Answer - Approximately 9 inches Newly hired personnel have to become licensed. - Answer - 1 year Force Mains and fittings must have a pressure rating of at least - Answer - 150 psi In the activated sludge process, for the clarifier to do its job, the must be retained long enough to allow to settle and Most pumping stations and electrical equipment used today in wastewater collection or treatment is and typically either or volts - Answer - (Alternating Current) & 220 or 440 and in some cases A.C. (Alternating Current) & 100 or 208 To avoid electrical shock, the operator should if they are experiencing equipment failures or power related issues - Answer - Refer the problem to a trained electrical repairperson and do not attempt to check fuses or open the disconnect box and Notify the power provider and let them send out a serviceman to assure the problem is not on the provider's side. When using Hydraulic Hydro Jetting sewer cleaning equipment the operator will want to go from a manhole and clean toward the stoppage to avoid . Answer - Clear or open / Forcing sewage into customer homes or businesses The Activated Sludge Process can produce a high degree of treatment. Typically one could expect a to % BOD removal - Answer - 90 to The Activated Sludge plant has five (5) Critical Components. They are - Answer - Oxygen supply, Aeration tanks, Clarifiers, Return & Waste The Activated Sludge process is an process. - Answer - Aerobic In the activated sludge process aeration tanks provide the space necessary to , , & and return biological solids. - Answer - Mix, aerate, & Hold Influent In the active sludge process, Utilization is the process where - Answer - Food supply is changed into a liquid state for use In the activated sludge process, Stabilization is - Answer - Wastes biologically converted to water, carbon dioxide, or new cells In the activated sludge process, the is called the heart of the activated sludge process. - Answer - Clarifier In the activated sludge process, factors that will influence the operation of the final clarifier are - Answer - Loading, solids applied, settling, thickness of solids, rate of return & Wasting In the activated sludge process, the clarifier will concentrate return sludge and waste sludge about to times the solids concentration of the mixed liquor - Answer - two (2) to four (4) In the activated sludge process, as more mixed liquor flows to the clarifier, the thickness of the sludge blanket will - Answer - Increase as solids accumulate In the activated sludge process, biological solids from the bottom of the clarifier must be returned to the aeration basin for re-seed. This process is accomplished by - Answer - Air lift pumps, centrifugal pumps, Diaphragm pumps, Screw pumps & Gravity Flow In the activated sludge process, no sludge process will work properly without - Answer - Regular removal of excess solids In the activated sludge process, Mass Balance refers to - Answer - Maintaining the balance between Return Sludge Flow, Return Sludge, Aeration tank volume, Mixed liquor suspended solids In the activated sludge process, the terms F/M ratio is important because this refers to - Answer - Food to Microorganism Ratio In the activated sludge process, the F/M Ratio is calculated by the pounds of by the pounds of MLVSS in the . - Answer - Dividing/ Incoming BOD/ aeration tank In the activated sludge process, the term Gould Sludge Age refers to - Answer - How long in days a pound of solids stays in the aerator In the activated sludge process, Gould Sludge Age (GSA) is calculated by - Answer - Dividing the total pounds of TSS in the aerator by the pounds of TSS entering the aerator as raw In the activated sludge process, the term Mean Cell Residence Time (MCRT) refers to - Answer - The amount of time the living cells are kept in the plant In the activated sludge process, daily observation of the aeration basin treatment processes are essential. The operator should pay close attention to - Answer - Surface turbulence, Foam, Odors, & Color In the activated sludge process, daily observation of the final clarifier is also essential. The operator should pay close attention to - Answer - Surface scum, Sludge blanket, Weir Flow, Rising solids, & Clarifier overflow In the activated sludge process, five (5) Important control parameters are - Answer - Dissolved Oxygen level, Aerator solids level, Solids quality, Rate of returned sludge, & Wasting rate