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SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEPTIC CARE INSTRUCTIONS
SEPTIC D-BOX INSPECTION
SEPTIC DRAINFIELD FAILURE DIAGNOSIS
SEPTIC DYE TEST PROCEDURE
SEPTIC FAILURE SIGNS
SEPTIC INSPECTION & TEST GUIDE
SEPTIC LIFE EXPECTANCY
SEPTIC SUPPLIES & PARTS
SEPTIC SYSTEM DESIGN ALTERNATIVES
SEPTIC SYSTEM DESIGN BASICS
SEPTIC SYSTEMS, HOME BUYERS GUIDE to
SEPTIC SYSTEM SAFETY WARNINGS
SEPTIC TREATMENTS & CHEMICALS
SEWAGE BACKUP PREVENTION
SEWAGE EJECTOR / GRINDER PUMPS
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SINKHOLES, WARNING SIGNS
SOAKAWAY BED FAILURE DIAGNOSIS
SULPHUR & SEWER GAS SMELL SOURCES
TOILETS, INSPECT, INSTALL, REPAIR
TRAPS on PLUMBING FIXTURES
TREATMENTS & CHEMICALS, SEPTIC
VIDEO GUIDES: Septic Videos
WATER CONSERVATION MEASURES
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WATER, WELLS, WATER TANKS: TESTING GUIDE
WASHING MACHINES & SEPTIC SYSTEMS
WASTEWATER TREATMENT BASICS
WINTERIZE A BUILDING
Septic tank cleaning or pumpout frequency guidelines or rules: this article provides a septic tank pumping schedule based on septic tank size and level of usage. This document explains a key point in how septic systems work: the septic tank & septic system cleaning schedule - when to pump out the septic tank.
We describe all of the reasonable methods for determining the recommended frequency for cleaning out a septic tank: using a cleanout frequency table, using objective measurements, using an electronic tank monitor. We also explain what is septic tank effluent retention time, why to measure septic tank scum and sludge levels in sum we provide a comprehensive guide to answering: How often should septic tanks be pumped?
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SEPTIC TANK PUMPING SCHEDULE - A Guide to Septic Cleaning - How Often Do You Pump Out A Septic Tank?
Table I given below lists the recommended septic tank pumping frequency according to septic tank capacity and household size. The frequencies were calculated to provide a minimum of 24 hours of wastewater retention assuming 50 percent digestion of the retained solids.
Common septic tank pumping frequency mistakes
See this complete list SEPTIC TANK PUMPING MISTAKES and fantasies about how septic tanks work and how they should be maintained.
Actually inspecting the septic system, diagnosing any problems or failures, and inspecting conditions inside the septic tank will tell us whether the tank is being pumped at the correct frequency.
The removal of septic waste by cleaning the septic tank is a critical step in septic system care as it extends the life of the septic field. Even if you don't care how septic systems work you need to know when to clean the septic tank by pumping out septic waste. Using the septic tank cleaning frequency table just below, simply look up your tank size and number of building occupants to see how often the septic tank should be cleaned. Later in this article we list other factors that can increase or decrease the recommended pumping rate.
|Septic System Failure Risk Level Factors|
|Septic Worksheet Risk "score"|
|0-8 = Low Risk||2-3 year septic tank inspections: Evaluate the septic tank conditions every 2-3 years to see if cleaning is needed. In MN some municipalities require septic pumping or inspection every 3 years. Requirements vary in other U.S. States & Canadian Provinces as well as of course municipalities in other countries.|
|8 - 18 = Medium Risk||1.5 - 2.5 year septic tank inspections: Evaluate the septic tank conditions every 1 1/2 - 2 1/2 years to see if cleaning is needed|
|19-26 = High Risk||Annual septic tank inspections: Evaluate the septic tank every year to see if cleaning is needed|
Adapted from the U. Minnesota septic tank pumping frequency worksheet cited below at reference 
 "University of Minnesota Septic Tank Pumping Frequency Guidelines", University of Minnesota, 2009 for extra copies of the original chart call (800) 322-8642, retrieved 1/15/2010, original source: http://septic.umn.edu/prod/groups/cfans/@pub/@cfans/
U.Minn assigns a numeric value such as 0, 1, or 2 or for some items 0-4 as the septic system load is likely to be increased. The homeowner adds up various risk number totals to reach a "risk score" that puts their system into one of three categories of septic tank "evaluation" frequency. "Evaluation of the septic tank " here means determine if it needs to be cleaned.
Really? What the heck does "Evaluate the Septic Tank" mean? This question is not addressed in the UM worksheet. Without septic tank inspection points, pass/fail criteria, or trouble signs for which the "evaluator" is to be alert, we just don't know what to make of this advice and we certainly can't expect any consistency in the results.
However we answer this question in excruciating detail beginning at SEPTIC TANK INSPECTION PROCEDURE where we list many things that should be evaluated to avoid septic system failures or worse, unsafe conditions; or you can "cut to the chase" as mom says, and have your septic contractor open the septic tank and MEASURE SCUM & SLUDGE, to know objectively if the tank needs pumping.
Watch out: "Evaluation of septic tank condition" is not well defined. Experts generally agree that there are a number of inspection points including the septic tank sludge and scum layer thickness that determine that septic tank pumping is needed (or not) but that there are other inspection points that are very important such as evidence of backup, damaged baffles, tank flooding or septic tank leaks, and of course septic tank safety: safe covers, no signs of collapse risk, etc.
If you don't know where the septic tank is located, see SEPTIC TANK, HOW TO FIND.
At TANK INSPECTION PROCEDURE we describe how to inspect the septic tank before, during, and after tank cleaning operations.
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I had some work done recently and if I sent a picture of the work, can you give me an idea of the quality of work? BTW, I love your site. - Syd
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem. And certainly from a photograph alone one can't make a full nor accurate evaluation of the condition of a septic system.
That said, I'll be glad to look at your photos and if the initial Q&A is sufficiently modest I will reply pro-bono. Of course as you gave no information about the topic, I can't say in advance how much I can comment on the pictures.
Reader comment - follow up:
I appreciate it. I used the information extensively when I bought this house. It is what clued me into the FPE panel I had and why when walking on the floor above the panel, the lights would sometimes dim (the breaker for the water heater was loose and arcing to the bus bar). I replaced the panel, breakers, etc..
Here are the specifics: Built in ‘84, in TN 4 BR, 2 bath, split foyer. Just my wife and I live here. Previous owners had 5 kids. The washing machine is on a proper grey water disposal system. The dish washer will be added soon.
Here's the story.
What started out 2 Friday's ago with a day off, I called the honey wagon to pump the tank. I have lived here for nearly 4 years and when I bought the house, the previous owners had the tank “inspected” and were informed that the tank did not need to be pumped. They lived here for 7 years and never had it pumped or checked. Now, the truck shows up and we start digging. Turns out that its not possible that the people that the previous owners had check the could have. The amount of dirt disturbed vs what I had to dig was way off. So the truck leaves and I dig a hole that is 5 feet deep by 4ft by 3 ft. By hand.
Fast forward to yesterday, truck comes back and we open the lid. This is when we find out that its approximately 2000 gal precast cement tank with 3ea 2.5x4ft hatches. Apparently this is rather uncommon around here. Also find that the exit baffle is nearly disintegrated however still in place. There was not an input baffle, in fact, it was a pipe that just poured waste onto the surface. The scum layer was 5 to 8 inches thick. I do not know how thick the sludge was, I had to go to home depot to get some pipe. Also, the input was right next to the output.
The driver pumped as much as he could (truck filled, he was expecting a 1000 gal tank which is common in this area), he got most the sludge and scum, 2/3 total volume removed. He recommended that a piece of pipe 2 ft. long be added to the input and to add a 4 in pipe with a tee on it. His method for installing the tee was to use PVC cement to a 2 ft long pipe, stuff the pipe down the output and secure with expanding polyurethane (great stuff) foam. You can see all of this in the picture. The pipe leaving to the drain field is orangeburg.
Here is what I think I know to be true: The tank was never correctly installed. I should have had the input moved and a tee or baffle installed. I should have asked him to come back to pump the rest of the liquid. I need to replace the orangeburg pipe soon.
So here are my questions: Since the system has been running like this 27 years and not pumped in at least 11 (could be 27 as well), do you think ill get another 10, maybe 20 out of it? Since the tank is rather oversized and its only the two of us, I think its safe to say the system is not taxed that much. We put a half gallon of spoiled buttermilk down the drain each month.
Thank you again for your assistance and for providing such an informative site with ACCURATE information. Feel free to use my picture of a hall of shame or whatnot.
About your note and photo - just in order of thoughts & your note:
7+4=11 years, probably longer than recommended for pumping the septic tank - see http://www.inspectapedia.com/septic/Septic_Tank_Pumping_Schedule.htm
2000 gal precast cement tank with 3ea 2.5x4ft hatches - probably a good tank, certainly decent size; if the liquid/sewage levels were normal then the tank is not cracked, damaged, leaking.
It would have been better to pump the whole tank out completely - we don't know really if the sludge was adequately removed from tank bottom, though it's possible for the pumper to probe and measure the sludge thickness that remained.
It was absolutely correct to add the tee at the inlet - it reduces sewer gas and sewage backflow into the incoming sewer line; I'm not experienced with using expanding foam to secure the tee
if it works both to hold the tee in place AND there is no groundwater leaking INTO the tank at that end, you're in good shape.
YOU SHOULD open the OUTLET end of the tank and be sure that there is an outlet tee in place - this is critical to avoid sending solids into (and ruining) the drainfield
Orangeburg pipe: old, very old, questionable condition; I'd like to see any photos if you dig up any of that material.
If you find there was no outlet tee, combined with infrequent pumping and orangeburg pipe, you will want to be saving/planning for drainfield repair/replacement.
I can't for sure predict how much life remains - a lot depends on level of usage, soil conditions. I've mentioned the tee - a predictor of field failure if it was missing.
Buttermilk is not a useful septic system treatment, though it won't hurt anything. You don't need to treat the system and in fact some treatments are harmful, even illegal. See http://www.inspectapedia.com/septic/Septic_Tank_Treatments.htm
I think I may have been misleading. The input from the house is the 3 inch pipe towards the top of the picture (under the shovel). It originally was just a 3in 90 that poured onto the top of the surface. The outlet is the field is the 4in tee. The input is now under the scum layer and does not have a tee. My picture shows what should be the output, however, when installed it appears that the contractor put the input on that side as well.
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