On the West Coast of the South Island of New Zealand, some podzol soils have such impeded drainage because of e.g. iron pans, that many farmers have adopted a soil flipping technique where the entire soil profile is inverted mechanically using large diggers.  This does not appear to have had many disadvantages as yet, although it is a fairly recent innovation.  Here are some links where you can find further information, if interested.

http://www.grassland.org.nz/publications/nzgrassland_publication_179.pdf

http://maxa.maf.govt.nz/sff/about-projects/search/01-231/land-development-booklet.pdf

http://farmersweekly.co.nz/section/arable/view/make-it-simple.

We have used ripping of soils in special circumstances such as hard pans, saprolite soils in gully treatment with ripping on contour and fertilization, highly compacted soils such as some roads to depth 0.6 m.  Consult a soil scientist.  Of the several soil scientists I have worked with, it would take some very special circumstances for them to consider deep soil mixing, as it would destroy any present soil development present.  I remember one sandy soil that was logged too wet after Hurricane Hugo, and the soils puddled (liquified) and this destroyed the soil structure, made like a huge mud bog.  However, I am not aware of subject research, so take that into account.

I have seen instances of roads puddling  where the slurry had to be removed, filled with logging debris or suitable fill and aggregate to continue use, at substantial added  expense.  When working on soils that liquify when wet, it is most cost effective and imperative to avoid site damage to conduct activities when conditions are dry, or at least dry enough to avoid rutting, even if postponing, unless you want to consider special treatment measures, low ground pressure equipment, wooden pallets for equipment support, corduroy roads made of logs with soil fill.  

We had some spodosols in coastal plain, poor site for trees, fertilizer did not help, they functioned as wetlands in wet years, non-wetlands in dry years, developed iron concretions that impaired tree root growth.  In years past, these soils were bedded and probably had some mixing, but no real change in productivity.  

However if research has been done on the soils and conditions you are working in, and you have consulted or have soils and other resource expertise to consider, it might be worth trying on some upland sites that are away from streams and riparian or other critical habitats.  We would probably have some degree of archeological review to check conditions.   Your country may require special permits due to potential for stormwater impacts of erosion/sediment and site recovery if the area does not revegetate well.  I would suggest a performance bond so operators do not abandon site if they go bankrupt, at least until this practice has been tried enough to be considered a standard practIce with reliable BMPs and implementation advice.

Thanks a lot Mr. Hansen

If I got it correctly, you believe that this method is not good for poor soil condition with liquefaction potential. 

Please introduce me proper references, if you have it.

After a brief look on internet, the term is apparently used to mix concrete or other amendments to strengthen soil for structural or bearing purposes.  i cannot comment on that specific use, if that is what  your intention may be.  I would defer to civil and structural engineers if your intent is to inject concrete, etc. to make buildings earthquake resistent or consult with geologists to shore up earthflows, slumping terrain or landslide prone areas.  Certainly with proper information and expertise, this type of deep soil mixing to some stable substrate would reduce failure hazards.  

If your intent is deep soil mixing to improve plant growth and recovery, that is the application I would be concerned about.  I could see in some landslide prone areas, if treatments would link unstable areas to stable geology in a proper technical way, address hydrological stress for subsurface flow passage, the unstability hazard is reduced, perhaps even all but eliminated depending on the circumstances.  As indicated, I do not dare suggest I am an expert on the subject, and professionals would not dare to prescribe treatments or sign their name to expensive treatments that make them potentially liable without undergoing full analysis.  As suggested, research and technical papers are not necessarily site specific prescriptions, so please continue to do literature review, but consult with appropriate professionals, conduct an environmental impact or similar document, especially if life or property are involved, licensed engineer review and approval when appropriate.

Since I dont know actual intent and conditions of application, it would be inappropriate to suggest "proper" references.  A literature and internet search should give you a good start and background, and I am sure there are licensed companies and professionals willing to take on this type work and may be willing to offer some advice or preliminary cost proposals in hopes of securing business.

There could be some remote, rural and conditions where life and property are not linked to project, where experimental or trial work, even prescribed applications might be acceptable.  Another consideration might be if you had a road where landslides or earthquakes have taken lives, this might be a structural tool to consider, along with considering any other standard practices.  However if working on landslides, geologists would consider materials, identify the depth or contacts where conditions are stable, and if there are slip planes, discontnuities or underground flow network to consider. 

Dear Rouhollah Basirat,

pl check following link.

http://www.ejge.com/2013/Ppr2013.024alr.pdf

https://www.dot.ny.gov/divisions/engineering/technical-services/geotechnical-engineering-bureau/geotech-eng-repository/GDM_Ch-14_Ground%20Improvement.pdf

On the West Coast of the South Island of New Zealand, some podzol soils have such impeded drainage because of e.g. iron pans, that many farmers have adopted a soil flipping technique where the entire soil profile is inverted mechanically using large diggers.  This does not appear to have had many disadvantages as yet, although it is a fairly recent innovation.  Here are some links where you can find further information, if interested.

http://www.grassland.org.nz/publications/nzgrassland_publication_179.pdf

http://maxa.maf.govt.nz/sff/about-projects/search/01-231/land-development-booklet.pdf

http://farmersweekly.co.nz/section/arable/view/make-it-simple.

Thanks a lot Mr Hensen, Meshram, and Hart.

Here in the Intermountain Northwest USD (Montana State); mixing surface horizons with sub-surface horizons ends up being a step in the wrong direction when it comes to soil productivity.  The reasoning why this is non-functional here is based on this area being influenced by the Cordilleran Ice Sheet (8,000-12,000 BCE) resulting in a nutrient poor glacial till horizons deeper in the soils.  Thus all of the nutrients are contained in the surface horizons which were influenced by past volcanic eruptions as thick ash deposition.  Results are a highly productive surface horizon with decreased productivity in deeper horizons.  This is believed to dominantly be a relationship with soil porosity in this area.

Top soil layer of 15-20 cm is beneficial for providing nutrients to annual crops. But deep soil may not be much useful as the nutrients may leach or may not be available to plants

I am not doubting the above. It is simply a statement that over here in the glacial till soils we have in the Pacific Northwest - it is not advisable to rotate soils.  Early true dozer harvest of trees in a very historical nearby area which were true-dozer operated in the 1950's for timber removal and bladed flat by pushing up soil columns of surface soils creating multiple parallel rows in an Andic Distric Eutrochrept.  These bladed alleys contain absolutely no trees; however the mounded areas to either side of historical rows contains healthy conifer (Ponderosa Pine).  Meanwhile, the bladed alleys are flat and easy to walk down 50+ years later. This is even after we received the 1980 Mt. St. Helens ash deposition. - FYI  

Dear Dr. Basirat,

(1). If you are trying to improve sandy soils with low water and nutrient retention capacity and the soils have higher clay content in deeper layers (due to illuviation), mixing of topsoil with the subsurface soil will be helpful. In such sandy soils with very low organic matter content, mixing of topsoil with subsoil at deeper layer may not have any significant disadvantage.

(2). In case of normal and fertile soils with high organic matter content in surface layer, mixing with subsoil of deeper layer will reduce fertility level.  

(3). There is another way of improving sandy soil (without mixing with soil from deeper layer). That is by compaction of surface soil by passing heavy roller over it. By this way, bulk density of the topsoil increases and water retention capacity of the soil improves.

I hope you find this input interesting and useful.

Thanks a lot!

If we have a desert location, but the water table is located in the ground surface or near of it, and a sand soil layer is located in the depth of 10-15 m, is there any potential for liquefaction? In this situation, deep soil mixing is a good method for improving the soil?

Thanks for the information Murray Hart - I will read into that asap - in the mean time my assumption is that this dominantly dealt with pasture or crop lands?  My work over here in NW USA - Montana State - is related to "timber productivity" and as such my focus is on nutrient relationships with very large conifer spp.....In those trees blown over in a clearcut unit - you can look at the underlying root system and what we have is a very shallow spread-out root system where the conifers are predominantly leaching from the nutrients which do not go very deep into the soil.  Once you get deeper you hit an extremely hard silty-clay glaciolacustrine deposit formed in the last movements of glacial ice from Canada into this area.  Such soils do not allow easy tilling and in places where we historically did so - we have minimal return of conifer and other forest-wide plant spp....Enclosed is a photo of a blown-over conifer in a recent clearcut which displays the glaciolacustrine subsoil.  Let me know if this did not attach - jgier

John,

locally, these soils are called 'pakahi' soils if memory serves, and are very scrubby, waterlogged pastures following the original clearance of the native vegetation.  They're so poor in terms of agricultural land use classification, it's always been a wonder to me why anyone would even try to farm on them.  Following the flipping, and necessary removal of previously buried tree debris and lumps of broken iron pan, grass growth is typically at least double that achieved prior to the soil inversion, making the large cost of the process worthwhile. 

Murray.

Sounds like an interesting study area and yes - the physical characteristics are completely different from what we are dealing with here.  I presume you have plans in place to not treat at least a sub-unit of the study area so you have a comparative end result.  Good Luck and I look forward to reading about it!