The hinged lid looks like a good idea. You could glue some astroturf on top to camouflage it from passers by.

We had a similar setup at a house I lived at in Illinois. We also had a lateral entrance through a passageway from the basement that was about 15 feet long.

HvdhU Wrote:
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> The hinged lid looks like a good idea. You could
> glue some astroturf on top to camouflage it from
> passers by.
>

You're forgetting that OP cries about the cost of concrete, steel mesh, scrap wood, and the cost of wear and tear of his shoelaces when he ties them. No way this guy is going to buy a hatch for his secret expensive hole that isn't a septic tank.

A hinged lid should cost around $350 to $550, which isn't that much considering all the trouble and aggravation it would prevent.

I still don't understand why he couldn't just break up the concrete into smaller pieces and then lift them out by hand. It wouldn't damage the hole if he used an iron bar to pound on.

OP is a homo.

not very expensive Wrote:
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> I still don't understand why he couldn't just
> break up the concrete into smaller pieces and then
> lift them out by hand. It wouldn't damage the
> hole if he used an iron bar to pound on.

Because there is a hole under the hole. The OP is being clever because the OP is doing unlicensed and unpermitted septic work.

We are on to you, OP!
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truth is OP did forget something while planning

OP could have gone smaller because a new concrete riser would safely offer footing across the eroding corner of the hole without breaking the eroded concrete (so i'd guess)

OP decided to go bigger to stay away from eroded concerete corner - completely forgetting to re-calculate the time it might take to "go bigger"

penalty: a larger 3' lid is like having to make TWO good 27" lids. going tad smaller would have been fine if just offset to miss the UN-SUPPORTED area. a little extra sweat and it will be done.

Un-inspected? the septic inspector made two mistakes last time. make me move a 4x4 that wasn't touching the tank top despite the fact the corner of the tank (the wall is rated for the load. on the other hand the inspector saw a thick bush growing on the tank which could easily grow into the tank (which i cut down) - the inspector didn't say a word of caution.

Some areas people are using UN-FASTENED LIGHT PLASTIC LIDS upon plastic risers which are highly questionable as to ability to hold weight or not crack during freezing weather (like those damn plastic chairs and plastic wheel-barrow trays). though many areas dis-allow it.

who inspected the inspectors allowing non-standardized plastic in a winter area ?

OP is a very retarded homo who must have caused major problems related to his retarded homoness because otherwise why would a septic tank inspector come to inspect your septic tank?

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un-fortunately, no ffu PO uploaded a CAD drawing (lame site - other sites people upload CAD designs !)

OP will just have to deny all these PO any authority to proceed upon advising until CAD drawings have been submitted and approved !

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INTO THE BATCAVE Robin!

You really need hinges. When you are hanging onto a metal ladder rung while trying to remove the lid it can be a royal pita. Get a bigger lid that has a collar which fits over the concrete. Make sure the hinges are sturdy enough to accept some lead shielding on the inside.

Even if you think you need the shielding properties of concrete for the lid, consider how difficult it will be to lift open from the inside. It sounds like you have another entrance, but you should be prepared to exit through that hole in an emergency. If a fire was blocking your escape you might not have time to position a jack under the concrete to lift it up.

It's a septic tank. OP had trouble communicating this information. The housing shortage is going to have to get much more dire before anyone is going to take up residence.

Dire Reah Wrote:
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> It's a septic tank. OP had trouble communicating
> this information. The housing shortage is going
> to have to get much more dire before anyone is
> going to take up residence.

Oh, I thought it was a bunker or bomb shelter with a vertical shaft entrance. There are a few of those around that were built back in the cold war days. I know of a house in Fairfax that has a nice one that can hold 20 people.

So i made this round riser and lid with a double rim and triple cross of 3/8" rebar (like i said, for 40" it's like making 2 lids). It will barely fit the riser which has little clearance to the orig hole - just enough for mortar really (orig is 24.5" and square).

I filled the lid with concrete and had it curing indoors. All this week it's dipping down to 24 degrees and if it dips to 20 degrees - the concrete would stop curing and all the time would be wasted, the lid unsafe as well.

Curing can take 7 days but in some conditions (environment and pouring status) it can take a month of sitting in a pond to cure - but it's winter.

So it's been curing for 4 days. All seems normal minus i troweled a little water on the top (ok, it's the middle/bottom that counts anyhow). I take off the plastic to wet it (2x or 3x a day). It's on a concrete floor in a room near a door, which has a spaceheater in the room to keep it temperate.

SO I REMOVE THE PLASTIC - ONE SIDE, ALONG THE RIM (sitting near the large door) has began to turn white - while the rest of it still a deep grey as usual. This didn't happen on the riser.

QUESTION

After wetting the whitened area it got some (maybe 1/2 or 2/3) of it's grey color back like the rest of the curing.

Should I assume curing stopped in that area and i have a weakened lid, or do you think the concrete is still curing (if not a little slower) ? If I'm lucky how much extra curing will be required?

Do you think it will be safe? Or do you think the concrete near the door, despite a heater being present, was enough to damage the curing ? I may have to weld together a new lid and pour concrete in a better protected environment?

uh - what was that about using a trashcan lid in the garage? i really think that was unsafe in the winter.

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lucky temperate zone bastard!

is that the lost city of Atlantis ? what are they doing ? doesn't concrete appear out of nowhere when you order it ?

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i'm pretty sure it was not simply that it ran out of moisure. the rest was still ponded, and all had been that way a day before as well.

oh i forgot to say concrete in this kind of application hopefully keeps curing it's whole life - gradually reaching 3x the strength - unless put out in harsh conditions (ie, above ground). if it ever reaches 20 deg it stops curing immediately and never restarts: ruined if not finished curing, throw out, do again.

visualize it like the above except the covered concrete is indoors. (it's typical to mist concrete and put plastic over it to keep it moist between wettings)

why did the side near the door get a lighter color (off-white) than the rest (deep grey) overnight? even areas that get dry to the touch between wettings don't change color. and the riser didn't have any such issue - weather was warmer

i can only think the concrete near the door is much colder. but it freezing wasn't predicted last night and isn't on the weather charts (on the other hand? it felt cold outside last night). but imho ground is warmer than air (especially several inches down) - i hadn't expected *any* issues.

i'm still perplexed if curing was effected