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TEXAS WASTEWATER CLASS B EXAM QUESTIONS WITH
COMPLETE SOLUTIONS GUARANTEED PASS BRAND NEW
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 - ANSWE>>>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
Non-point discharges are - 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 - 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 - 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 - ANSWER>>>Chapter 26 and Texas Commission of Environmental Quality The Texas Commission on Environmental Quality can revoke an operator's license if the operator - 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 - ANSWER>>> Aerobic Bacteria require_____ in the water for their metabolism - ANSWER>>>oxygen Anaerobic Bacteria _____ live with O2 present in the water for their metabolism - ANSWER>>>cannot Facultative Bacteria require__________in the water for their metabolism - ANSWER>>>either aerobic or anaerobic conditions
Chemical characteristics of sewage include - ANSWER>>>solids, greases, dissolved oxygen, O2 Demand, pH, and gasses _________removes Total Suspended Solids (TSS) - ANSWER>>>filtration Inorganic solids include - ANSWER>>>sand, grit and minerals Organic solids include - ANSWER>>>organic materials from plants, animals or humans A good plant influent pH is about - ANSWER>>>7. Dangerous gases are produced during bacterial decomposition of organics 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. 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
______ 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 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 Unstable anareobic sludge contains streaks of _________ or ________. - ANSWER>>>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>>> Calcium Hypochlorite (HTH) is a strong _______ and reacts violently with _________. - 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 Effluent dosage of chlorine in the contact chamber must produce a total combined residual of - ANSWER>>>1.0 mg/L after 20 minutes
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 An effective way for the collection system worker to prevent infection by waterborn pathogenic organism is to - ANSWER>>>Wear protective clothing and avoid direct contact with waste water _________will increase the chances that sewage will turn septic - ANSWER>>>Stoppages in the main line Extensive use of garbage disposals (grinders) in a community would likely have the following effect on the collection system - ANSWER>>>Increase the amount of flow, solids, and grease The minimum size for a gravity flow sewer line on city right-of-way and the minimum grade is - ANSWER>>>6 inch and a grade of 0.50 percent
The most accurate way to find the average wastewater flow rate in an existing 10-inch sewer main is - ANSWER>>>Obtaining actual flow data & verifying with field data What is the greatest advantage for using fiberglass manholes in areas with high groundwater? - ANSWER>>>fiberglass is not subject to infiltration A __________ pump would most likely be used when discharging into a 10" diameter pressure sewer main. - ANSWER>>>Centrifugal Excessive power consumption by a pump could be caused by - ANSWER>>>Worn bearings and worn impeller Trench safety is a great concern in Texas. OSHA requires that anytime an excavation is greater than __ feet deep it must be protected by ______. - ANSWER>>>5 feet / An approved Trench Box, Shoring, or Sloping 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. - ANSWER>>>3 feet / 25 feet laterally A ____________ would be the best to determine if a storm drain is connected to a sanitary sewer line. - ANSWER>>>Smoke Test _________ would most commonly be used to seal a number of joint leaks on a main with minimal interruption - ANSWER>>>internal grouting Pre-treatment of wastewater would include: -
Solids in wastewater are classified as - ANSWER>>>Total (TR), Suspended (TSS), Dissolved (TDS), Settleable (SS), Nonsetteable, 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 Organic matter in wastewater can be ______or________and makes up approximately _______% 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. Acute toxicity occurs when - ANSWER>>>There is a rapid die off of treatment organisms
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
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 99% 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, for the clarifier to do its job, the ____ must be retained long enough to allow ______ to settle and liquid to rise. - ANSWER>>>water/ solids 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
solids level, Solids quality, Rate of returned sludge, & Wasting rate In the activated sludge process, Dissolved Oxygen levels throughout the aeration basins are measured using a portable DO meter. The operator should keep DO levels between ______ and _______. - ANSWER>>>2 mg/L and 4.0 mg/L In the activated sludge process, "Classic Bulking" is a common problem typically caused by - ANSWER>>>Low density sludge In the activated sludge process, Sludge Rising differs from "Sludge Bulking" and "Sludge Rising" is typically associated - ANSWER>>>Nitrification - De-nitrification process In the activated sludge process, techniques used to reduce "Frothing & Foaming" typically include - ANSWER>>>Adjusting sludge age, Reducing the amount of air, Spraying the frothing area with water, Applying de-foaming agents In the activated sludge process, floc is very important to the settling process. Floc is composed primarily of - ANSWER>>>Bacteria, Protozoa, Microscopic Animals, & Fungi In the activated sludge plants, the operator will experience problems. Some of the common Treatment plant problems include - ANSWER>>>Insufficent capacity, Equipment failures, Design inadequacies, Poor maintenance, & Inflow rates exceed plant capacities. In the activated sludge plants the operator will experience problems. Some of the common Influent problems include - ANSWER>>>Septic inflow, Organic overloading, and under
loading, Hydraulic overloading, Solids washout during storm inflow, Toxic substances, Shock loads, & Nutrient deficiencies In the activated sludge plants, the operator will experience problems. Some common Operational problems include - ANSWER>>>Sludge quality, foaming, improper operating techniques In the activated sludge plants, the operator will experience problems. Some common Environmental problems include. - ANSWER>>>Low temperatures, System pH out of range, & Excessive algae growth In the activated sludge plants, to properly set the clarifier return rate the operator must know three things - ANSWER>>>Return activated sludge rate, Sludge blanket thickness, & the Solids concentration of the return flow The typical sludge age for extended aeration plants is - ANSWER>>>20 to 40 days In the activated sludge plant, good quality sludge will settle _________& _______ over _________ minute period. - ANSWER>>>Gently & Uniformly over 15 to 20 minutes In the activated sludge plant, old sludge quality will settle ________& _________ over ________ minute period. - ANSWER>>>Rapidly and ragged over 5 minutes. 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.
