Septic tank -Install risers and access covers on concrete cover

[rkpatt]

Default Install manholes (access) hole in concrete septic tank cover
The septic tank at my house built in the mid 1970s has a three piece concrete lid (3 rectangular sections ) . When I have had it pumped , they usually dig enough soil to remove one section of the cover . They have "offered" to installed a manhole or something for $200 . I would like to install something like two 12"-24" manholes (risers and access covers ) so that I can maintain a filter on the outlet tee , monitor the inlet tee and make pumping less destructive to the landscaping . My questions is mainly how do I cut the holes in the concrete cover sections without damaging them (don't have to perfectly round or smooth ). - Thanks

example of septic tank risers - http://www.septicsolutions.net/store/TufTite.htm

example - of septic tank outlet tee filter - http://www.thenaturalhome.com/septicfilter.htm

[joed]

Remove the existing covers and leave off. If the hole is too big perhpas a thick metal plate over the hole with a hole cut into it will work.
Or call some local septic or water tank installers. They mak have a concrete riser that will fit over the existing hole.

[AllanJ]

You mean the septic tank has no (round?) hatches for pumping and the pump man has to lift off an entire section of the top leaving say a 3x4 foot opening?

If the existing concrete covers are not steel reinforced, cutting a (15" round? 12x18" rectangular?) hatch could make them too weak to bridge the width of the tank.

So you may need to have replacement lid sections (steel?) fabricated with access hatch, riser if desired, and hatch cover. Looks to me that a 3x4 foot steel section would need upturned edges and/or ribs stamped into it for rigidity.

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