Vactor Dumping Pad (for Decanting of Sewer Cleaning Solids)

[MarshfieldTimC]

I'm searching for a simple design for the 'decanting' of sewer cleaning truck (Vactor) solids. We'd like to dump the Vactor solids onto a containment pad (similar to a concrete slab with curb & gutter around three sides), let the solids sit for a bit, while draining the liquid run-off into the headworks of our wastewater treatment plant. After the solids have dried, we'll scoop them up with a small loader and haul them off for landfill disposal. We generate approx. one load of solids per week, with each load totaling approx. 6 CY of which approx. 2 to 3 CY are (dewatered) solids.
Has anyone designed or used something like this?
Thanks in advance for the replies.

 

[ashtree]

Yes.
A plant i work with has exactly this type of facility although smaller in capacity than what you describe. The concrete slab is about the size of a truck with a sloped entry. There is a 8 inch kerb around the other three sides. On one side there is a screened gully inlet that goes into a small pumpstation that pumps ultimately back to the headworks.

There are a couple of problems.

1) It is a source of rainwater infiltration during rain events.
2) The screened outlet had to be fitted with a stop board so that when a truck dumped there was some settling time before flow was allowed off the slab.
3) It is very slow to drain.
4) It is difficult to pick up the sludge etc with a machine. Often the sludge is fairly runny unless left for days. A machine simply can't clean the slab well enough so there is often manual labour involved.
5) Depending upon what the vac truck has been cleaning the outlet screen and down stream pumps can get blocked. Sometimes some manual picking is required.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"