Outechnics for an excellent & solid base

According to DIN E 1997-1, a subsoil investigation must be carried out for every building as the basis for structural planning and the geotechnical report must be prepared according to DIN 4020. The soil-mechanical properties of the subsoil determined in this way form the basis for e.g. the verification of foundation stability, the forecast of settlements, the planning of building waterproofing, the possibility of rainwater infiltration, the durability of traffic routes, or the requirement of excavation securing. Our geotechnical engineering department examines the subsoil according to engineering geological aspects and the requirements of DIN EN 1997-2 and advises, plans and optimises the design of the geotechnical trades according to constructional, environmental and economic aspects.

  • Creation of exploration and investigation concepts
  • Subsoil investigation and evaluation
  • Field exploration
  • by means of small pile driving, light and heavy pile driving, pressure soundings, in-situ tests, etc.
  • Soil mechanics field and laboratory tests
  • Infiltration tests (open-end tests, double-ring infiltrometer, etc.)
  • Planning and evaluation of pumping tests, incl. technical and metrological support
  • Compaction and bearing capacity tests in earthworks and road construction (static and dynamic plate load tests)
  • Soil expertise / subsoil expertise / geotechnical reports and statements Foundation consulting

If you have any questions, please do not hesitate to contact us:


For every new building, a subsoil investigation must be carried out as the basis for structural planning and a geotechnical report prepared in accordance with DIN 4020. Often, the site geology results in constraints for the foundation planning, which - in inner-city situations - have to be dovetailed and optimised with the concerns of deconstruction and environmental concerns.

When carrying out the subsoil investigation and foundation/pit planning in the course of a deconstruction and / or remediation planning, duplication of effort can therefore be avoided and critical paths of the construction process and the construction period can be clarified at an early stage.

Our geotechnical engineering department examines the subsoil according to engineering geological aspects and advises and optimises on the foundation and the necessary auxiliary structures of special civil engineering, such as shoring walls, underpinning, sealing and water retention.

  • Design and planning of earthworks and special civil engineering measures
  • Excavation and foundation planning
  • Earth static calculations according to DIN EN 1997-1
  • Settlement predictions, optimisation of subgrade reaction coefficients
  • Water law permit applications
  • Tendering of earthworks and special civil engineering measures
  • Cost estimate
  • Expert opinions on neighbourhood permission agreements

If you have any questions, please do not hesitate to contact us:


New Project 67

The staff of the Landfill Department and the specialist colleagues from the other departments involved plan, assess and monitor your landfill projects or related projects in the context of contaminated sites. Thanks to the expertise of our staff in the field of "landfill", which has grown over decades, and the associated technical issues, from the search for a site, through all technical aspects, over the lifetime of a landfill, to the PV or other subsequent use of a landfill, we guarantee you professional and economically optimised work. We would be happy to advise you.

  • Professional planning and documentation in all HOAI service phases
  • Application and coordination with involved experts and official communication
  • Local construction supervision and site management
  • Internal and external monitoring of landfill construction work
  • Health and safety coordination
  • Expert opinion, advice


  • Assessment of existing geological barriers
  • Base seals
  • Multifunctional sealing ("landfill on landfill", so-called intermediate sealing)
  • Surface sealing (also in the context of contaminated sites)
  • Optimised use of landfill substitute construction materials
  • Quality management

Landfill behaviour, leachate, landfill gas:

  • Optimisation of landfill volume, geotechnical assessment with regard to load increase
  • Geotechnical stability verifications
  • Rehabilitation of drainage facilities, coordination of cleaning and TV inspection
  • Planning and assessment of leachate collection and treatment incl. leachate prognosis
  • Planning and assessment of landfill gas collection and treatment, calculation of gas prognosis, landfill aeration or oversuction, FID measurement

Re-use / integration in the surroundings:

  • Planning of PV installations or other consequential uses
  • 3-D modelling with landscape image analysis

Other topics:

  • Site search
  • Follow-up cost calculations
  • Economic feasibility studies
  • Accompanying landscape conservation planning (SaP, special species protection assessment)
  • Annual reports

If you have any questions, please do not hesitate to contact us:


New Project 67

We offer our services with regard to testing, monitoring, expert opinions and technical support in the fields of geotechnics, soil mechanics, soil, geology, hydrogeology and geosynthetics for all projects in which the relevant knowledge, experience and expertise is required. Especially in the landfill sector, but also in road construction, subsoil investigations or soil and building material testing of all kinds.
Our specialists and experts will be happy to help you with your enquiries or projects.
  • Accredited third-party testing in landfill construction for mineral building materials and geosynthetics as well as asphalt
  • Self-testing in landfill construction
  • Quality assurance in earthworks
  • Soil physics laboratory tests
  • Carrying out waste and environmental chemical investigations
  • Geotechnical investigations/ground investigation in landfill construction
  • Geological and hydrogeological investigations
  • Carrying out FID inspections further environmental investigations at landfills

If you have any questions, please do not hesitate to contact us:


It was not only hard coal that was mined in Germany for several hundred years. Other raw materials of stone and earth, such as ore and salt, have also been mined in Germany for a long time. At many mining sites, we have now entered the post-mining era.
In today's densely populated mining regions, legacies from former mining times pose serious civil risks and subsoil risks. These include, in particular, inadequately secured former mining zones, openings that have not been preserved in accordance with the current state of the art, such as shafts or tunnel mouth holes and abandoned open-cast mines.

Due to increasingly dense settlement and post-daily land use, additional issues arise, such as the stability of mine workings, open pits or shafts, as well as the regulation of mine water or outgassing situations, for which sustainable, economic and ecological technical solutions must be found.

These must not only be taken into account in the planning and development of new construction projects, but can also pose a considerable risk potential for existing structures, open spaces and traffic routes.

Not only the direct effects of mining activities mentioned above, but also the peripheral phenomena such as dumps, waste rock piles, sludge ponds, clarification and sedimentation basins are now part of the mining legacy that must be considered in a sustainable subsequent use of the land.

We are accredited by the mining authority of North Rhine-Westphalia as publicly appointed and sworn experts for old mining (Dr.-Ing. Scherbeck, Dipl-Geol. Stempelmann).

We offer expert support, planning services and advice on the following typical topics:

Near day mining

  • Mine image inspection and subsequent mining geotechnical site analyses of the hazard situation.
  • Exploration in the area of influence of near-surface mining (deposits and mining cavities) including the conception of the exploration, tendering or implementation of the exploration work, construction supervision, expert monitoring and documentation of measures.
  • Remediation planning including tendering of the commercial securing services, technical supervision and documentation.

Old shafts and gallery mouth holes (day openings)

  • Assessment of the stability of shafts and gallery mouths as well as conceptual design and planning of structural measures for securing and safekeeping.
  • Tendering of the securing and custodial works.
  • Expert monitoring and construction supervision of mining, civil engineering or drilling rehabilitation measures, documentation of measures.

Opencast mines and residual mining holes

  • Engineering geological survey, evaluation and planning for securing rock and loose rock slopes.
  • Preparation of geotechnical and mining concepts for the backfilling of residual opencast mining holes including engineering geological and rock mechanical calculations.
  • Advice on the preparation of final operating plans.
  • Tender for the safeguarding work.
  • Expert monitoring and construction supervision of remediation and protection measures, documentation of measures.

Mining damage

  • Recording of mining-related damage to buildings, land and other structures.
  • Carrying out the preservation of evidence.
  • Mining geotechnical site analyses.

Mine gas

  • Expert evaluation of the existing outgassing situation
  • Planning of outgassing protection

If you have any questions, please do not hesitate to contact us: