Not technoSOIL, but technoSOL.
The former is rare and seems to be confined to a few translated texts. The latter is apparently the standard term:

"A Technosol in the FAO World Reference Base for Soil Resources [1] is a new type of soil that combines soils whose properties and pedogenesis are dominated by their technical origin."
http://en.wikipedia.org/wiki/Technosols

Macías himself uses both "tecnosuelos" and "tecnosoles", apparently interchangeably, in this document entitled "Tecnosuelos: suelos a la carta"
http://edafologia.ugr.es/gestionsuelos/grupoa/tema15tecnosue...

"La elaboración de Tecnosoles y Biochar derivados de residuos, a imagen de los suelos naturales y a medida de los requerimientos de corrección de los suelos contaminados y/o degradados existentes, (“taylor made Technosols” o “Tecnosoles a la carta”), puede constituir un proceso que atienda simultáneamente a la valorización biogeoquímica de los residuos, permita la recuperación de las funciones del suelo en espacios degradados y/o contaminados"
Sociedad Española de la Ciencia del Suelo
http://www.secs.com.es/conf_murcia.htm

This text is translated, admittedly, but the term "technosol" is probably reliable:
"Thus, the preparation of Technosols from mixtures of organic and inorganic wastes can be an attractive option to rehabilitate mining areas because they can improve physical, chemical and biological properties contributing, at the same time, towards a strategy of wastes valorisation (Macías, 2004)."
http://biblioteca.universia.net/html_bura/ficha/params/title...

"Fig 7 Use of different Technosols derived from wastes in the recovery of hyperacid soils and waters in the restored Touro mine (Galicia, NW Spain; Macías-García et al. 2009a, b)"
http://www.springerimages.com/Images/Geosciences/1-10.1007_s...

Soil carbon sequestration in a changing global environment
by Felipe Macías, Marta Camps Arbestain
"Within the latter option, the following actions are considered here in more detail: 1) production of Technosols, and 2) production of biochar."
http://www.mendeley.com/research/soil-carbon-sequestration-c...

--------------------------------------------------
Note added at 2 hrs (2012-01-30 19:28:17 GMT)
--------------------------------------------------

The Wikipedia entry is largely copied from the FAO's "World reference base for soil resources 2006", where "technosols" are frequently mentioned and are an established category, albeit a new one:

"TECHNOSOLS
Technosols comprise a new RSG and combine soils whose properties and pedogenesis are dominated by their technical origin. They contain a significant amount of artefacts (something in the soil recognizably made or extracted from the earth by humans), or are sealed by technic hard rock (material created by humans, having properties unlike natural rock). They include soils from wastes (landfills, sludge, cinders, mine spoils and ashes), pavements with their underlying unconsolidated materials, soils with geomembranes and constructed soils in human-made materials.
Technosols are often referred to as urban or mine soils. They are recognized in the new Russian soil classification system as Technogenic Superficial Formations."
ftp://ftp.fao.org/agl/agll/docs/wsrr103e.pdf

This document does not read to me like a translation.

Certainly it is a new word; indeed it was included in the WRB for the first time in 2005 and included in 2006. The author of the proposal, D G (David) Rossiter, Coordinator of the WRB Working group on Technosols, works in the Netherlands but is American.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.114...
http://www.itc.nl/about_itc/resumes/rossiter.aspx

http://www.amazon.com/Technosols-Ferdinand-Maria-Quincy/dp/6...

I think the evidence is clearly that this term is now officially established in the field, and is quite clearly what Marías's English-speaking colleagues now call this type of soil