To preserve leaves mix 1 part glycerine and 2 parts water.Submerge leaves in mixture in a single layer.Weigh the leaves down so that they are completly submerged in the solution.Leave them for 2 to 7 days until they have completely absorbed the solution and are soft and pliable.Remove and wipe dry with a soft cloth.Done correctly leaves should last indefinitely.Leaves done this way may be used in floral arrangements. I think this would be the perfect way to preserve the leaves used for the cement and hypertufa objects all of you are making.This really works.A florist friend told me about this. God bless...........Lillie

I recently had my septic tank dredged and the opening is about 2 feet beneath the surface. When I purchased the house the inspector wasn't quite sure where the tank was so they had to do some exploring. When they dug into my yard to reach the tank it left about a 2 ft x 2 ft bare spot in the grass. Rather than replant grass over the bare spot I chose instead to create a circular design of river rocks to mark the opening for future reference. If the tank had been located in an area where I needed to plant, I would have felt comfortable planting perennials with the understanding that they would have to be dug up every 5 years or so for a tank cleaning.(A foot of soil is more than sufficient for perennials to thrive) And annuals would be easy on top of the site. I would be concerned about planting things with deep taproots-- these tend to be your monocots like grasses and milkweed-- not because they would wreck your tank but because these plants might not survive a transplant after your next dredge. Most oaks have deep roots -- I believe Pin Oaks have shallow roots. I'd leave your oak alone for the time being and let the septic guys come back to you with a recommendation as to whether or not the roots could damage your tank. There is probably a way for you to do some selective oak root pruning without putting the oak at jeopardy. I would still mark the opening of the tank with a rock or something.

a gas operated "demo saw" , theproblem is not the holes thats easy [if you call that kinda work easy] its the concrete debree that will fall in the tank i would atach a peice of unistrut, with drop in anchers and bolts, to over span the hole, then cut it out, and lift the peice up and away man hole rings are sold in 12" increments, and a cast iron sewer man hole cover is 7" so..7" and 19" are your minnimum heights

A couple of comments. Not so long ago a toddler was killed as you described in MA (I don't know if this is the same incident you're referring to). Very tragic, but it should be noted that the cover was raised off the ground a good five inches and the toddler was climbing/jumping on it unsupervised. Further it was not seated properly and it was the support condition around the perimeter that allowed the round metal lid to just flip open, the toddler fell in, and the lid flopped closed. Freak accident that I don't believe is a chronic problem. That being said, concrete lids that I have seen fit into a tapered opening in the top slab. The lid is simarly sloped (wedge shaped) to fit into the taper. You can form a piece to cover the hole/fit in the opening and cat it yourself. I'd suggest looking up a local precast concrete manufacturer and asking if they have any stock item that would work. If not send them a sketch of what you want and have them give you a quote to make it. Remember concret is ~150 lbs./ cubic foot so it will need to be picked up or shipped which will add to the price. Hope this helps