In soil_bulk_density table, field sample_id defines the depth where the sample was taken ([0-0.1],[0.1,0.2],[0.2,0.3]). As the field is a Free Text Field, we can see multiple ways to fill that information (even showing metres and centrimetres, etc.)
We can also see 3 site visits whose sample_id are (1,2,3) instead of (0,1,2), the most common pattern. This would crash any attempt to automatise the cleaning and reformatting of the field.
If would be very helpful to clean this field in the source and maybe create some controls to validate what is introduced in DB.