Living With An Aerobic Treatment Unit And Spray Field
B-623401/10Living with anAerobic Treatment Unitand Spray FieldBruce J. Lesikar, Diane Bowen,Justin Mechell, and Ryan Gerlich*If you own an aerobic treatment unit and sprayfield, you are required by law to make sure thatyour system is treating wastewater adequately.To do this, you can either contract with a companyto conduct the required system inspections, wastewater tests, and report completion and submittal tolocal governmental agencies, or you can do the workyourself.For both options, you’ll need to know the components of your wastewater system and understandhow they work. Basic information about aerobicsystems is given in these Texas AgriLife ExtensionService Onsite Wastewater Treatment Systems series: Aerobic Treatment Unit Tablet Chlorination Liquid Chlorination Ultraviolet Light Disinfection Pump Tank Spray Distribution SystemThese publications are available on the Web athttps://agrilifebookstore.org/.You also need to know the basics of aerobicsystems inspection and their maintenance. Forinformation on general onsite wastewater treatmentsystems, see Extension publications Onsite Waste*Extension Agricultural Engineer for Biological andAgricultural Engineering, Editor and ExtensionCommunications Specialist, Extension Program Specialist andExtension Assistant, The Texas A&M University Systemwater Treatment Systems: Operation and Maintenance and Understanding and Maintaining YourSeptic System.And unless you don’t mind repairing andreplacing it often or having system backups, you’llneed to adopt household practices that will protectand prolong the life of your system.Performing the work yourselfAn advantage of doing the inspecting, testing,and reporting work is saving money. You also canbe certain that the work has been done properlyand the reports are filed on time. However, if youconduct the work yourself, you will need to: Get informed. To maintain an aerobic onsitewastewater treatment system properly, youmust have extensive knowledge. This knowledge can help prevent injury to yourself,other people, the system components, andthe environment. Obtain the manufacturer’sliterature describing system components andthe particular maintenance practices from thecompany’s Web site. For a list of courses formaintenance providers on maintaining aerobicsystems, see the Texas Commission on Environmental Quality (TCEQ) Web site at http://www.tceq.state.tx.us. For a listing of coursesoffered through the Texas AgriLife ExtensionService, see the Wastewater Treatment andReuse Web site at ––––
Spray headsChlorinatorSingle-compartmenttrash tankPump tankAerobictreatment unitFigure 1. Example treatment train for residential aerobic wastewater treatment with a spray field. Know and abide by all state and any localrequirements for wastewater quality, testing,and reporting. Inspect the system at specified intervals, usually once every 4 months, to check its operation and perform routine maintenance. Wear protective clothing—such as rubbergloves, and safety glasses, goggles, or faceshields—during the inspection and testingactivities. Observe stringent personal hygiene practices. Be adequately vaccinated against diphtheria, hepatitis B, and tetanus. Also considerprotecting yourself from hepatitis A, paratyphoid, polio, and typhoid fever. Collect and handle the wastewater samplesproperly. Conduct tests on the wastewater. Submit a report on each inspection to thelocal authorized agent. Take measures to avoid illness and accidents.Common hazards associated with onsitewastewater treatment systems include diseasecausing microorganisms, electrical shock,insects and animals, poisonous or explosivegases, exposure to sewage through cuts andabrasions, and confined space entry. Thiswork increases your risk of sickness, physicalinjury, or death. Keep records on the system performance andyour service activities. Recognize the tasks that should be left toprofessionals to make sure that the job is performed correctly and that you do not subjectyour family to undue health risks. Know local service providers who can handlethe tasks you are not trained to perform. Acquire sampling and testing equipment suchas a chlorine DPD field test kit, profile probe(Sludge Judge ), dissolved oxygen test kit,pressure gauge, and a graduated container forsolids sampling tests. Keep on hand any manufacturer-required specialty tools and parts. Have common hand tools such as a cordlessdrill and bit set, shovel, and wrenches. Keep other supplies, such as the permit/as-built plans/specifications, governmentalforms, a calculator, the system owner’s manual, a flashlight, insect repellent, and a first aidkit. Keep on hand the proper disinfectant, such aswastewater chlorine tablets or liquid bleach, toadd to the disinfection component.2
If you try to carry out maintenance activities thatare beyond the scope of your training, the resultscould include but are not limited to voided warranties, destroyed components, additional problemswith the system, higher repair costs, personal injury,and even death.If you do not maintain the system properly, youcould endanger human and environmental health,impair your wastewater system, and incur legalaction.Human health: Because sewage can containdisease-causing microbes, wastewater is a publichealth concern.Environmental protection: The EPA has set nationalguidelines for management of onsite and wastewatertreatment systems. The guidelines are posted on theWeb at http://cfpub.epa.gov/owm/septic/home.cfm.System reliability: All system components from theplumbing fixtures in the home to the spray heads inthe yard must be functional within expectations.Legal action: By law, water that leaves your property, either through runoff or by seepage into theground, must meet certain quality standards asdemonstrated by laboratory tests. If your wastewatertreatment system is not maintained properly, thewater will not be treated enough, and you may besubject to fines. Know the kinds of contracts available. A basicmonitoring contract meets the state’s minimum requirement but requires more maintenance activities by the homeowner. Othercontracts offer more service and limit thehomeowner’s involvement in the operation,maintenance, and monitoring of the system. Choose the amount of work you want to do, ifany, and make sure the contract states clearlywho is responsible —you or the maintenanceprovider—for performing the different tasks. Evaluate the maintenance contract. Knowexactly what services you are paying for andwhat is included in the base price of the contract. Basic information on evaluating servicecontracts is available in the Extension publication, Onsite Wastewater Treatment Systems:Homeowner’s Guide to Evaluating ServiceContracts. Pay attention to the work being done to ensurethat you’re getting what you’re paying for.Understanding your systemAll water, including wastewater, is part of thehydrologic cycle (Fig. 2). After the effluent is dispersed from a wastewater system, it eventually joinsground or surface water, both of which are used assources of drinking water. Because of this cycle, thewater must be treated properly to protect humanand environmental health.Contracting with amaintenance providerThe advantages of contracting with a maintenance provider include saving you time, eliminatingthe hassle of maintaining the system yourself, andsparing you the cost of replacing a system prematurely because it was not properly maintained. It canalso ensure that reports to the government are filedproperly and on time.The disadvantages include the costs and theoversight of activities provided by the maintenanceprovider.If you contract with a maintenance provider, youwill need to: Research local maintenance providers thatprovide this service. Understand the terms used in on-site wastewater system maintenance contracts.PrecipitationClouds accessed through wellFigure 2. The hydrologic cycle.3RunoffInfiltration toground water
Aerobic treatment units can remove substantialamounts of contaminants that are not eliminatedby the simple sedimentation that occurs in a septictank. The aerobic process also breaks down dissolved solids and ammonia and reduces the numberof pathogens in the waste.tablets release chlorine gas. Do not storechlorine tablets in the house, garage orstorage areas with metal tools.-- Ultraviolet (UV) light is another disinfectantfor wastewater. In this process, a lampemits UV light into a chamber or zone aswastewater passes through the chamber.The UV light destroys the microorganisms in the effluent by altering their geneticmaterial and retarding their ability toreproduce.Aerobic system processesIn onsite wastewater treatment systems, microorganisms convert waste into less harmful substances—water, carbon dioxide, and new cells.Aerobic treatment systems consist of several processes that work together to provide a high-qualityeffluent: Removal of gross solids (trash): After the wastewater leaves the house through a pipe, it entersa trash or septic tank, where the solids in thewastewater settle to the bottom or float to thesurface. Aeration: Air is pumped into the aerationchamber of the unit, and the wastewaterremains in the chamber long enough to allowthe microbes to convert the waste. Aerobicsystems must have a continuous supply ofoxygen to keep the microbes healthy. Clarification: The clarifier removes the microbial cells, cell waste, and dead cells from thewastewater. Sludge return: The solids that settle in the clarifier are returned to a previous component tobe treated further. Disinfection: Systems using spray distribution of effluent include a disinfection unit aspart of the treatment system. In the disinfection process, disease-causing organismsare destroyed or inactivated. However, thewastewater is only disinfected, not sterilized(free of all life). The main disinfectants usedin aerobic systems are chlorine and ultravioletlight.-- Chlorination is the most common form ofdisinfection for aerobic systems. In thisprocess, chlorine is added to the wastewater to reduce the number of pathogens init. The chlorine oxidizes and destroys thecell enzymes of the pathogens. There aretwo types of chlorinators—tablet chlorinators and liquid chlorinators. ChlorineSpray fieldsIn the final stages of treatment and dispersal, thewater is dispersed into the soil. Systems that spraythe effluent onto lawns are called spray fields (Fig. 3).For these systems, the effluent must be disinfected toreduce the risk of human exposure to pathogens.Pump tankSpray headsFigure 3. Spray field components.Although a spray field is like a lawn sprinkler, itshould be viewed very differently. The water beingdistributed is treated wastewater—not drinkingwater. Residents and pets should avoid contact withit. Texas regulations specifically prohibit effluentfrom being applied to vegetable gardens becausesome pathogens are resistant to disinfection.Selecting an aerobic system sizeEach aerobic treatment unit is sized to treat aspecific amount of wastewater. Aerobic treatmentunits are available in a range of sizes, includingthose able to treat 500, 600, 750, 1,000, and 1,500gallons per day.4
Table 1. Sizing of wastewater aerobic treatment units for single-family residence of various sizes.Numberof bedroomsSquare footageof houseTexas minimum unitcapacity (gal/day)Traditional unitcapacity (gal/day)1 or 2Less than 1,5014004503Less than 2,5014006004Less than 3,5014807505Less than 4,5016009006Less than 5,5017201,0507Less than 7,0018401,2008Less than 8,5019601,3509Less than 10,0011,0801,500To select an aerobic unit, first determine theamount of daily wastewater flow from your home orsmall business.The rate of daily wastewater flow is based onthe home’s square footage or number of bedrooms,whichever is larger (Table 1). Then choose a Class Iaerobic treatment unit that can handle that amountof flow. The TCEQ maintains a list of Class I aerobictreatment units approved for sale in Texas. Theseunits are listed by company, model number, ratedtreatment capacity, and requirement for a trash tankin the treatment system.Water-conserving fixtures can make the wastewater too strong for a system to treat adequately.Therefore, many treatment systems are overloadedorganically (too much waste), which requires thatthe sludge be removed from the systems more oftenthan normal.Most residential aerobic systems can treat 500gallons a day or 60 gallons per hour. This assumesthat the wastewater contains an amount of organicmatter common for homes; it is typically inadequatefor businesses.contain only the products of normal activities ofa home. If other substances enter the wastewaterstream, they may disrupt the system’s performance.The system’s ability to treat wastewater is affectedby several factors, including the system’s capacity,the amount and strength of the wastewater, the timing of the wastewater entering the system, and thetypes of materials it receives.Sometimes an aerobic treatment system canmeet the minimum state requirement for gallons ofwastewater treated per day, but its capacity per hourmay be too small for a family’s normal activities.For instance, if a 500-gallon-per-day system canhandle only 60 gallons per hour (1 gallon per minute),and a normal clothes washer uses 30 to 40 gallons ata time, the residents may have to curtail other waterusing activities when doing laundry.To alleviate that problem, a flow equalizationtank may be placed between the trash tank and theaeration chamber. The tank will hold the wastewaterand send it to the aerobic treatment unit at a rate itcould handle.Know your system’s capacity. This informationshould be on the permit or the control panel labelfor the aerobic treatment unit. If more wastewaterenters the system than it was designed to handle, itwill not operate as intended.In addition to the amount of wastewater that thesystem can treat, the strength of the wastewater theProtecting and prolongingthe life of your systemAn onsite wastewater treatment system isdesigned to treat domestic sewage from a homeor similar facility. The wastewater stream should5
treatment train can handle is limited. If the wastewater is too strong, it can overload the system, making it unable to meet wastewater quality regulations.Similarly, if the wastewater contains constituentsthat are toxic to the microorganisms, treatment willbe affected.ate as filler. Keep these out of the system toimprove its long-term performance.-- Bleach additives can affect the biology of theseptic tank and the rest of the system. Donot overuse bleach.-- The amount of laundry done each day is alsoimportant. Spread out the loads over timeto help the system perform at its best. In-home businesses can directly affect thesystem. Use for daycare increases the overallflow and can increase the use of antibacterial soaps. The system can also be affected byother small businesses that use chemicals,such as antique refinishing services, beautyshops, lawn care services, photo labs, doggrooming services, and taxidermy shops. Barbershops typically discharge large amounts ofhair. Prescription antibiotics and drugs are extremelyhard on the microbes in the system. Flushingthem into the wastewater system increases themaintenance. Heavy use of bath and body oils can raise the fats,oils, and grease (FOG) values in the system.Removal or reduction of these can improvethe performance of the system. A garbage disposal adds to the overall loadingof the system in four ways:-- More waste enters the treatment system.-- Because the organic matter has not beendigested, it takes longer to break down.-- More water is used to rinse out the sink.-- Smaller particles take longer to settle.Therefore, people who use garbage disposals athome need a larger system to treat the wastewater and more maintenance activities arerequired. Toxic drain cleaners kill the bacteria, resultingin a limited microbial activity in the tank andpoor separating characteristics. Antibacterial soap also affects the biology of thetank. Liquid soap tends to be easily overused and maycreate problems in the system. Automatic cleaners (for toilets and showers) continually send chemicals into the system, whichcan cause long-term problems.Recognizing treatment interferencesAn aerobic treatment unit needs a regular supplyof wastewater. To treat wastewater effectively, the unitneeds to maintain a stable population of microbes.Any extreme influxes of wastewater flow or strengthwill impair the unit’s performance.Your system can be affected by the amount,strength, and timing of the wastewater entering it.These household devices, practices, and productscan alter an aerobic system’s performance: Water-saving devices reduce the amount ofwastewater, but they also make it stronger,which can prevent the system from meetingthe required effluent standards. Whirlpool or jacuzzi tubs (inside) typically uselarge amounts of water. Their use will affectthe wastewater treatment system by exceedingthe hourly flow limit of the treatment unit. Multi-head showers or multiple showers used atthe same time can introduce large volumes ofwater into the wastewater treatment system.A flow equalization tank and additionaltreatment capacity are needed to handle theincreased amount of wastewater. Water-treatment devices with automatic back flushing add extra water into the system that can beavoided. Some water-conditioning units add chemicalsinto the effluent that can reduce the effectiveness of the biological and physical processesin an aerobic treatment unit. This wastewaterstream may need to be plumbed around thetreatment tanks to the pump tank. Condensate from air conditioning units is not sewage. Route it around the system. Commercial ice machines can also add largeamounts of clear water. Laundry activities greatly affect your wastewater system:-- Powdered detergent can plug cast-iron piping,and some soap contains forms of benzo-6
usage such as excessive laundry, which can result inlower quality water passing through the system. Other cleaning products may also alter the treatment process. When choosing a cleaningproduct, first read the label:-- Danger means that the chemical will killthe microbes; use it rarely or never.-- Warning means that limited use should notaffect the system much.-- Caution typically means that the productwill have little effect on the system. Excessive amounts of toilet paper cause sludge tobuild up faster. Treated toilet paper, such as the type that contains lotion, does not settle well and forms athick layer of scum at the top of the tank. Other paper products, such as wet wipes, shouldnot enter the system. Flushable cleaning products, many wipes andtoilet cleaning materials are labeled as “septic safe.” This statement typically refers totheir ability to flow through the piping. Theseitems will collect in the treatment system andincrease the need for maintenance. Trash and nondigestible material increase theamount of maintenance required and may evenshorten the life of the components. Examplesare rags, toys, diapers, condoms, cat litter,plastic bags, coffee grounds, cigarette filters,and feminine hygiene products. Many of theseitems have neutral buoyancy and will passthrough the treatment components. Cat litterand coffee grounds add to the sludge that mustbe pumped out during maintenance. Diapersmust be removed individually.Make a list of the cleaning and antibacterial products used in your home. When using these products,keep in mind that they can have a cumulative effecton the treatment system. If something will harm themicrobes in the system, do not send it down the drain.Preventing rainwater from overloading the systemAn onsite wastewater treatment system isdesigned to handle a specific volume of wastewater.If rainwaterenters the system, the proper operation can be disrupted.Water collecting over the components can leakinto them. Also, the tanks are installed in an excavation that is backfilled with material that can collectwater. If the system is not watertight, the collectedwater can enter the system and flush sewage throughthe treatment system and into the yard.Evaluate these conditions to determine whetherrainfall may be affecting the system: Look at the ground over the tanks to see ifa depression has developed where rainwatercould accumulate. Rainwater infiltrating thesystem can overload the treatment components. Evaluate the color and growth of grass aroundthe tank. Excessive growth and darker greencolor than the other grass in the yard indicatesthat the tank or piping is broken. If the tank has a riser, verify that it is in goodcondition and properly sealed to preventinfiltration. Check the inside of the riser/tank seams forstains that would indicate that groundwater orsurface water is entering the tank. Evaluate the system performance during rainyperiods: Rainwater may be infiltrating thesystem if there is an unexplained number ofdosing cycles or water flow and/or if the spraydistribution system is spraying during a rainshower.Protecting your family and petsReturning after vacationAn onsite wastewater treatment system is treating sewage using containers to hold the wastewater,microbes to remove contaminants, electrical components to move air and water and sense water levels,electricity to power the electrical components, andchlorine/UV radiation to disinfect the wastewater.By their nature, these parts and components pose arisk to public health, environmental health, publicA vacation or extended absence develops a condition of limited food supply in the wastewater treatment system. The microbial population is reduced,which also reduces treatment once the vacationerreturns and wastewater addition resumes. Therefore,the wastewater loading should be increased graduallyfor the first couple of days, which allows the microbialpopulation to grow. Avoid greater than average water7
safety, and pet safety. If the system componentsare in areas often visited by your pets and family,greater attention is needed when selecting treatmentsystem components, implementing component safeguards, keeping chlorine disinfectant in the unit,and keeping the components functioning properly,which may include upgrading existing systems.Reduce these risks by limiting access to thesecomponents. Safety practices include installing fencing for components, risers with heavy concrete lids,lighter lids with safety screws, lighter lids with locking mechanisms, lighter lids with internal restrictions to access, and control panels with screws and/or locks.Use products only in accordance with theinstructions on their labels. As the system owner,you are responsible for following these safety practices.TroubleshootingTroubleshooting involves identifying and correcting sources of system breakdown. If a component is found to be inoperable during an inspection,troubleshooting is often required to bring it back tointo operation. Contact a trained professional maintenance provider to identify and fix the problem.For more informationA comprehensive guide for homeowners, Checking My Aerobic System: General Guidance for Monitoring Aerobic Treatment Units, Disinfection Units,and Spray Fields in Texas, is available at the TexasAgriLife Extension Service Bookstore at https://agrilifebookstore.org. Also available at that site isOnsite Wastewater Treatment Systems: Respondingto Power Outages and Floods.This publication was funded, in part, by the Rio Grande Basin Initiative administered by the Texas Water ResourcesInstitute of Texas AgriLife Extension Service, with funds provided through a grant from the National Instituteof Food and Agriculture, U.S. Department of Agriculture, under Agreement No. 2009-45049-05492.The information given herein is for educational purposes only. Reference to commercial products or trade names is madewith the understanding that no discrimination is intended and no endorsement by the Texas AgriLife Extension Service is implied.Produced by AgriLife Communications, The Texas A&M SystemExtension publications can be found on the Web at: http://AgriLifebookstore.orgVisit the Texas AgriLife Extension Service at http://AgriLifeextension.tamu.eduEducational programs of the Texas AgriLife Extension Service are open to all people without regard to socioeconomic level, race, color, sex, disability, religion,age, or national origin.Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as amended, and June 30, 1914,in cooperation with the United States Department of Agriculture. Edward G. Smith, Director, Texas AgriLife Extension Service, The Texas A&M System.5M, New
Aerobic treatment units can remove substantial amounts of contaminants that are not eliminated by the simple sedimentation that occurs in a septic tank. The aerobic process also breaks down dis-solved solids and ammonia and reduces the number of pathogens in the waste. Aerobic system processes In onsite wastewater treatment systems, micro-
How Aerobic Treatment Works Aerobic systems treat wastewater using natural processes that require oxygen. Bacteria that thrive in oxy-gen-rich environments break down and digest the wastewater inside the aerobic treatment unit as they are suspended in the liquid. Like most onsite systems, aerobic sys-tems treat the wastewater in stages.
Aerobic Digestion is a biological process similar to Activated Sludge. Activated Sludge Growth Aerobic Digestion Decay. Aerobic Digestion Processes vs Activated sludge processes Practical Approach To Help Understand the Difference! Activated Sludge Aerobic Digestion . Aerobic Digestion Chemistry 1. Digestion: C 5H 7NO 2 5O
The 3M Petrifilm Aerobic Count Plate is a ready-made culture medium system that contains modified Standard Methods nutrients, a cold-water-soluble gelling agent and an indicator that facilitates colony enumeration. 3M Petrifilm Aerobic Count Plates are used for the enumeration of aerobic bacteria. AC Aerobic Count Plate .File Size: 2MB
and aerobic digester is optimized for effective nitrogen removal. 12minutes aerobic and 12 minutes anoxic phase gave better nitrogen removal compared to all the cycles. Over all the aerobic digester gave about 92% ammonia removal, 70% VS destruction and 70% COD removal. The oxygen uptake rates (OUR's) in the aerobic digester are measured
aerobic exercise and a control session, in random order and on separate days. After the short-term sessions, all the patients will be randomly allocated into four groups and followed up for 8 weeks (between design): mild aerobic ex-ercise group, moderate aerobic exercise group, high-intensity aerobic exercise group and the control group.
aerobic exercise approaches is considered and has a place in mental health practice. According to many studies aerobic exercise is the preferred form of exercise for patients with MDD. Moreover, Aerobic exercise has been proven as an effective treatment for MDD, and there are sufficient studies to help health
wastewater treatment. These include aerobic, anaerobic, and facultative ponds. 2. Aerobic Ponds contain dissolved oxygen (DO) throughout the entire depth of the pond all the time. Treatment is accomplished through the stabilization of organic wastes by aerobic bacteria and algae. Dissolved oxygen can be introduced into a pond through several means.
Robin Readers by Level Ages 1-3 95 titles Ages 4-5 29 titles Ages 6-7 29 titles Ages 7-8 5 titles 3. How Robin Readers are graded? Robin Graded Readers have four levels: Foundation, Easy Start, Beginner and Elementary. With the i-Pen readable function, Robin Graded Readers are designed to nurture a love of reading in children which in turn enrich their vocabulary and consolidate their ability .
