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

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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 in wastewater. The main gasses are - Answer - Hydrogen sulfide, carbon dioxide and methane 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 least days. - 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 Organic matter in wastewater can be or and makes up approximately Secondary treatment typically used today would include - Answer - Stabilization ponds, trickling filters, rotating biological contractors (RBC) & activated sludge Essential components of the wastewater collection system include - Answer - Sewer mains & piping, Lift Stations, Pumps, Grease & Sand traps, & Manholes Grit removal would be considered - Answer - A part of Primary Treatment The protozoa that causes dysentery would most likely be destroyed by - Answer - Disinfection Using final plant effluent in cooling towers would be a - 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 - Answer - Bypass Enforcement action from TCEQ may be taken if pollution or waste violates the Texas Water Code. Violations of Water Code may include - Answer - Unauthorized discharge, accidental discharge & health hazard Solids in wastewater are classified as - Answer - Total (TR), Suspended (TSS), Dissolved (TDS), Settleable (SS), Non-setteable, Floatable, Organic and Inorganic Total Suspended Solids (TSS) are those that - Answer - Can be filtered out Total Dissolved Solids (TDS) are those that - Answer - cannot be filtered out Settable Solids (SS) are those that - Answer - Settle out when left standing for extended periods of time Non-settleable Solids are - Answer - Small particles that do not settle Volatile Solids (VSS) are those that - Answer - Are determined by burning the residue from the Total Solids determination Inorganic Solids (ash) are those that - Answer - Consist of sand, grit, & minerals and can be suspended or dissolved % of the total solids - Answer - Dissolved or Suspended / 65 The typical pH of an influent entering the plant will vary from - Answer - 6.5 to 8.0 Acute toxicity occurs when - Answer - There is a rapid die off of treatment organisms Digester gas typically contains about % - Answer - 65-75% methane 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 (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 Answer - Clear or open / Forcing sewage into customer homes or businesses The Activated Sludge Process can produce a high degree of treatment. Typically one 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) treatment is and typically either or volts - Answer - A.C. go from a manhole and clean toward the stoppage to avoid . - could expect a to % BOD removal - Answer - 90 to 99% minute period. - Answer - Rapidly and ragged over 5 minutes. in the effluent from an activated sludge process is a pollutant and may create toxic conditions for aquatic life in the receiving stream - In the activated sludge plant, there are (5) important nitroen transformation processes that occur by microorganisms. They are- - Answer - Assumilation, Ammonification, Nitrification, Denitrification, & Nitrogen fixation. Denitrification occurs in an activated sludge system when there is to maintain the aerobic metabolism of the carbon stabilizing bacteria. - Answer - Insufficient Dissolved Oxygen The lack of triggers the facuitative bacteria to change from aerobic and anaerobic - Answer - Dissolved Oxygen In the activated sludge system, "Hydraulic Wash Out" is - Answer - When the upward movement of the water in the clarifier exceeds the downward settling velocity In the activated sludge system, Hydraulic Wash Out can be controlled by - Answer - flow equalization, Additional clarifier capacity or inflow reduction In the activated sludge system, if the operator observed Boiling action, Violent turbulence throughout the aeration tank surface, Large air bubbles 1/2 inch or greater, the operator would suspect- - Answer - Over aeration resulting in high DO and or floc shearing therefore the operator should reduce the air SCFM to get DO into the proper range In the activated sludge system if the operator observed uneven surface aeration, dead spots or inadequate mixing in some areas, the operator would suspect - Answer - Plugged diffusers In the activated sludge system, if the operator observes white thick billowing sudsy foam on the aeration tank, the operator would suspect - Answer - Overloaded aeration tank and or excessive sludge wasting In the activated sludge system, if the operator observes excessive air being used with no apparent change in organic or hydraulic loading, the operator would suspect - Answer - Leaks in the system piping, Plugged air diffusers & High organic loading The maximum safe withdrawal rate for a 150 lb chlorine cylinder is - Answer - 40 lbs To determine the approximate number of gallons per day being discharged to the collection system, multiply the population by gallons/person/day. - Answer - 100