So, you are considering what type of slurry store to build, and would like some guidance? Okay, let us get started. On one side you will find the “Pro”, the positions in favor:
The first point in support of earth bank slurry stores is going to be their simplicity of construction.
The secondary positive point is the low cost when a suitable low permeability in-situ clay soil exists on your site to use as the lining medium.
A third favorable point is that they are usually buried and below ground so that the slurry and liquids is easily drained or pushed downhill into the store by normal farm machinery and using normal tractor attachments.
A fourth big benefit is with a slightly elevated rim they quickly green-up and are visually unobtrusive.
Lastly, the fifth reason for support will be that a slurry store of this type can be an entirely farm resourced project, perhaps only requiring the services of a guy with an excavator machine, for the farm to complete.
And on the reverse side, for balance, the Con side, against:
The leading point against earth bank slurry stores is that unless well sited they may be inundated in wet weather, especially if they are within the flood plain of a river and release their contents causing pollution.
The second point against will be that with their sloping banks they may be subject to erosion and instability against collapse, unless well designed with suitably stable shallow sloping sides.
The third point against is going to be that they form their own additional rainfall catchment due to the way that the normal 750 freeboard slops out beyond the edge of the wetted perimeter, adding to the volume of slurry/ polluted water that the farm must dispose of safely.
A fourth negative point is going to be that with the gradient of their sides they take up much more farmyard space than a vertical walled slurry storage design.
Fifth and lastly, against is that the bottom of the tank is below the water table, inward seepage of water may occur, if they are not carefully designed by an expert.
So there we have all the arguments from each side.
So, in the final analysis are earth bank slurry stores the good thing, or just a bad thing?
Both questions appear to have a “yes” answer! earth bank slurry stores appears to be both good AND bad! It must be left up to you, the reader to decide. Which side, the good or the bad, has got the preponderance of weight of opinion?