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Septic system pumping

Justin_DeSilva | Posted in General Questions on

We recently had our septic system pumped for preventive maintenance. Our tank shows two caps on the site plan. I thought it was odd that the septic company only pumped from one cap, the cap closest to the distribution box.

When looking inside the tank through the cap I recall the shape looking squarish. Should the company have pumped from both caps, meaning the tank may have been constructed of two compartments?

The system was installed in 1998. Location: Massachusetts

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  1. tommay | | #1

    Nope, that's normal. It's just one big tank. The two access covers are there so when you pipe the tank you can seal and install a tee inside the baffles on either end.

    1. Justin_DeSilva | | #6

      Hey Tom,
      You were correct, I stuck a rod down under and noticed the tank wasn't square but rectangular. I see you wrote something interesting. Does this mean the yellow filters should be placed on the inlet and outlet sides of the tank? I didn't know if that's what was meant by baffles.

      "The two access covers are there so when you pipe the tank you can seal and install a tee inside the baffles on either end"

      1. tommay | | #9

        As others have mentioned, there are different tank designs. If you look at my other reply, you should be able to look inside to see the configuration of the interior of the tank. The baffles are the concrete partitions within the tank that hold back the sludge and allow the more fluid material to be separated from it. They also keep floating debris from clogging up the open areas of the baffles which would prevent flow to the outlet. Normally when pumped, the liquids and floating debris are removed and a portion of the sludge is left to inhibit digestion. If the sludge gets to deep then they should remove some of it. Not sure about the filters you mentioned, just seems like something that would cause more problems or maintenance. The tee is there to act as a "wall" to shatter the incoming material as a first step in breaking down the solids as well as to direct the waste downward into the tank to minimize "floaters".

  2. Jon_R | | #2

    If they mix it up well, then I don't think it matters where they pump a single tank from.

    If it has two large access covers (vs small inspection pipes over the baffles), then it probably is a dual tank.

    I'm curious, did you measure the sediment level or just have it pumped based on time?

    Just had one pumped that had gone 20 years. It was pushing sediment out.

  3. George_7224612 | | #3

    In fact, you probably have a two compartment tank. The first compartment, on the inlet side, is about twice the size of the one on the outlet side. The first compartment collects most of the solids. The pump company should have pumped both sides and used a rod to stir up the sludge on the bottom for more effective removal. Tanks installed after 1975 are usually two compartment tanks. Mine was installed in the mid 90s. We just dug it up and relocated it to accommodate the new house.

    1. tommay | | #5

      Well, it looks like he'll have to stick his head inside to find out......

  4. walta100 | | #4

    Does your tank have a filter that should be cleaned every few months?


    1. Justin_DeSilva | | #8

      Hey Walta,
      The tank shows piping for one but was missing the yellow plastic filter. We recently installed a new one in July.

  5. Justin_DeSilva | | #7

    Hey everyone,
    When our system was pumped I knew very little about septic system components. Looking back I was dissapointed the title 5 inspection service and separate septic pumping service didn't ever mention the tank was missing filters. I added a filter to the exit side of the tank but don't know if we should add another at the entry side of the tank. Would anyone know?

    1. Jon_R | | #10

      I think an intake filter would quickly clog up.

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