Soil sample evaluation

Hello dear forum members,

I plan to purchase a plot of land within a new development area. This development area is currently being developed. Three soil samples distributed within the area (40 plots) are available. Before I buy the plot, have soil samples taken on my plot myself, and only after the purchase find out that high costs due to non-cohesive soils / soil replacement > 1 m depth etc. are coming my way, I would like to hear your opinion on the soil samples.

"4 Summary
It is planned to develop a new residential area with the necessary roads, access paths and public spaces as well as the sewage system.
The building ground consists of topsoil over sand, which in one part of the area is characterized by silty to strongly silty material down to a depth of 1.4 m.
Groundwater was encountered in November 2014 in exploratory drilling between elevations GW11-20014 ≅ +6.1 mNN and +6.5 mNN (surface distance approx. 2 m). It is to be expected that the groundwater can rise to just below the surface after prolonged rainfall.
The cohesive soil present in one part (loamy sand) tends to soften when exposed and when surface water or interstitial water penetrates and is classified as medium to very frost-sensitive (F 2 and F 3).
For road construction, base layer reinforcements and the use of a geogrid or soil improvement measures, e.g. lime stabilization, must be planned.
According to DWA recommendations, the present loamy sand is unsuitable for the infiltration of rainwater. The non-silty sand is well permeable.
For the dewatering of excavation pits and pipe trenches, closed water retention via wells or a vacuum system with flushing filters must be planned.
For the main backfilling of pipe trenches, well-compacting material (gravel sand) is to be used, installed in layers with a compaction degree DPr ≥ 97 %.
The building ground is generally sufficiently load-bearing for the planned construction of single-family houses with proper treatment. However, detailed geotechnical investigations of the building ground are still required for the construction."


Additional information:
- the soil was formerly arable land (corn)
- we plan to build our single-family house without a basement

Can one already say from the text and the graphic what might be expected?

I am grateful for any advice.

It’s all there, isn’t it?

However, detailed soil surveys are still required for the development.
What good is a soil survey that is 20, 30, 40 meters away from your building plot? None. So, go to the soil expert, and do it before buying. With a reputable seller, you won’t have any problems with that.

Then find the structural engineer you trust and discuss it with him. No one here knows the planning and which loads will be applied. And do that before signing with a preferred house provider. Better to waste a bit of money now than to be unhappy for a lifetime. That would be "stinginess is not cool."

I would leave it... open water management and other measures only make building unnecessarily more expensive... we also have clay soil with layered water. Even now in summer I have problems with puddles and mud. And here the groundwater level is something like about 30 mNN (living on a hill/mountain). I constantly get annoyed by the layered water and would never build on clay soil again...

And I would consider a well in the garden. Could be interesting.

And I would consider a well in the garden. Could be interesting.

What is meant by this?

Look at the groundwater level.