Technical map of the Minette region in southern Luxembourg marking Esch-sur-Alzette for FONTANA-EOD explosive ordnance assessment and surveying

Explosive ordnance surveying in Differdange when construction plans change

A building moves, an access road changes or a retaining wall is added: these changes may also alter the ground works to be assessed. For your construction project in Differdange, we compare the proposed areas and depths with the existing records together with you before further specialist services are defined.

Building position

Show changes of position on the plan.

Vertical reference

Read ground level and construction depth together.

Scope of results

Assign existing reports appropriately.

Discuss the project's technical requirementsExplosive ordnance assessment in Luxembourg
Assess the construction project

What must be compared when an excavation moves?

Before ground works in Differdange, compare the new excavation with the earlier investigation plan, including working areas, ancillary structures and the vertical reference. Specialist planners assess which existing findings cover the present ground works and what additions are required. For private specialist work, the permitted scope of services and Luxembourg prerequisites are clarified before work begins. Send old and new site plans and the complete investigation reports.

Project site

Connect the site with the specific construction task

Schematic map of Luxembourg with a crowned lion coat of arms, beside a tablet, white hard hat, pen and notebook.

Using the Mathendahl example to compare your own plans

The change at the time relates building position, road elevation, property geometry and a retaining wall. For your project, these details are brought together using your own plans. Technical preparation concerns the ground areas actually changed. The historical planning example establishes nothing about the present investigation status of another site; that requires its complete reports and current ground works plans.

Differdange is in the south-west of the Grand Duchy of Luxembourg. Identify the specific project location, for example Niederkorn, Oberkorn or Lasauvage, and the affected address. A location within the municipality is distinguished from a neighbouring project. For Mathendahl, identify the relevant PAP, its version and construction lot. The Gersheim headquarters coordinates the enquiry; local prerequisites depend on the actual location and proposed specialist work.

For the regional context of your construction project, the south-west Luxembourg overview provides further local information.

Luxembourg
Local context

Mathendahl: building positions and elevations were adjusted together

The fourth amendment to the Mathendahl PAP

The explanatory report on the fourth amendment to the ‘Mathendahl-2, 3, 4 & 5’ PAP in Niederkorn dated 25 April 2022 describes changes to several construction lots. For lots A1 to A6, the proposed building elevations were to be adjusted to the road already constructed. For A5 and A6, the houses were also to be moved back to improve garage access.

Changed ancillary structures and investigation scope

The report also addresses revised property geometry and a retaining wall to accommodate a change in ground level. This raises a practical question for explosive ordnance planning: does an existing investigation result also cover the changed location and depth of the construction work? The planning document itself provides no evidence of a completed explosive ordnance investigation.

The University of Luxembourg documents the use of forced labour at the Differdange steelworks between 1942 and 1944. This documented wartime use forms part of the local history; it does not establish contamination of every present construction plot. For a specific site, available historical records and later changes are assigned spatially. Comparison with current plans then shows which parts of the area previously considered still fit and where additional findings are needed.

Working together

Distinguish the tasks of client, designers and specialist contractor

Client and operator

The project owner describes the project and provides existing records. Operators add information on use, access and timing requirements. A coordinating contact brings the information together. The parties agree their respective tasks and decision responsibilities. Before commissioning, the records identify missing information, who will obtain it and which decision the result is intended to support.

Planning and construction management

The specialist designers describe areas, depths, construction methods and changes. Site management coordinates the planned sequence with the construction contractors and agreed specialist works. Results are assigned to the respective intervention. A technical plan change is communicated early enough for its effect on the survey task to be assessed before construction. Organisational construction stage boundaries remain distinguishable from technical survey boundaries.

Specialist company and competent bodies

The private explosive ordnance specialist carries out the agreed investigation and documentation work within the permitted framework clarified for Luxembourg. The technical report identifies the task, areas actually covered and limitations of the findings. Required notifications and evidence relate to the activity and personnel deployment. The responsible Luxembourg bodies make the decisions assigned to them. The state SEDAL service carries out its responsibilities for found ammunition. The specialist contractor and project participants agree the necessary handovers with the responsible bodies.

Investigation task

Which specialist task comes next?

Assessing existing findings within their scope

Check which area, depth and technical question a report concerns. A general completion notice should be read with the full appendices. Suitable further services are defined from the remaining questions. Existing results that fit are taken into account; a new drawing alone makes earlier investigations neither worthless nor freely transferable to other ground works.

Compare the existing investigation scope

Describing survey conditions for additional areas

Report known installations, paved surfaces and access limitations. The technical investigation must be capable of providing the required findings under these conditions. Areas with limited interpretation are documented accordingly. Planning then describes how the outstanding question will be addressed for the proposed work, rather than indiscriminately extending a neighbouring assessment to this area.

Compare investigation methods
Project types

Relating revised positions and elevations to the existing findings

Illustration: aerial photographs and maps on two screens and printed on a desk.

Assigning historical assessments spatially

Earlier aerial photograph analyses and other historical records are provided with their maps. Show whether today’s excavation lies wholly within the area considered at the time. This relates the technical assessment to a defined area. Later plan changes must be compared with that scope; the same property name does not replace a traceable presentation of the spatial relationships.

Assign each earlier report to the map it used. If the plan title and property do not match, clarify these differences first. For Mathendahl, identify the individual construction section with its current boundaries; the overall area name does not sufficiently describe the spatial scope of an earlier assessment. Also mark known fill, excavation or changes to operational areas since then. Historical sources and later investigation data remain identifiable with their respective dates.

Arrange specialist assessment of historical evidence
Two people with a tablet beside a marked construction area; plans lie in the foreground.

Determining the specialist service from the changed ground works

A moved excavation may affect different areas, while a new elevation changes the depth range required. Describe both changes. Specialist planners consider existing results, access and installations when selecting suitable services. A small change in position does not automatically require a particular method; what matters is which findings are still missing for the actual ground works.

For an offer, identify each changed structural element with its investigation objective. A deeper foundation, moved excavation and lateral connection may have different requirements. State which options have been decided and which remain open. The offer can then describe the scope actually needed, possible limitations and expected results documentation. Access and preparation requirements are assigned to the responsible parties.

Compare specialist services
Illustration: two people review plans and documents at a table beside a construction vehicle.

Handing over applicable results with the new plans

The complete report remains available with its maps and limitations. Site management can identify which ground works plan version the current assignment concerns. Changes are not passed on solely by word of mouth. Where supplementary work is needed, it receives a defined spatial and technical scope distinguishable from the part already covered adequately.

For handover, record which site plan and section drawing versions the assessment concerns. Site management also receives the appendices identifying limitations and areas not investigated. If the planning consultancy or construction contractor changes, outstanding questions are passed on with the affected structural element and next work step. A later addition is clearly linked to the existing report so that earlier and new results can be used together.

Document findings and their limitations
Preparation

Prepare the scope and commission together

Establish what needs to be known before commissioning the work

First establish which decision the commission needs to support. Is the task an initial assessment of existing documents, an investigation of a specific area or examination of an anomaly that has already been assessed? These tasks require different evidence. A general wish for safety does not define an investigation that can be carried out. The enquiry therefore specifies the groundworks, location, depth and available findings. Suitable specialist work and the required reporting are then agreed on that basis.

Define the specialist task

Coordinate preparatory work with the investigation

Required access and survey conditions are clarified before the site visit. This may include keeping areas clear, obtaining service information and coordinating with other trades. The method and site determine which preparations are actually needed. Changes to the surface or additional groundworks are not undertaken unilaterally simply to prepare for a survey. Their sequence is agreed with the specialist designers and responsible parties.

Clarify preparatory work in the programme

Agree a clear scope and schedule

A sound workflow distinguishes work already clarified technically from outstanding prerequisites. If an area will be accessible only in part, commissioning must take this into account. Handover and assessment of results also need time in the construction sequence. An enquiry therefore does not imply a blanket commitment on dates or cost. Specific coordination connects the described scope with access, documents, execution conditions and the date by which a decision is needed.

Discuss the scope and schedule
Tasks at the site

Comparing more than the building outline when plans change

01

Recording the moved excavation

Moving a house on the site plan does not necessarily keep the excavation and working areas within the same area investigated earlier. Show the old and new positions together. Which results remain usable can be assessed only against the actual investigation plan. An unchanged property name is insufficient on its own.

02

Relating depths to the same elevation

A construction depth may be measured from existing ground, a planned surface or a fixed elevation point. These references must remain identifiable during comparison. If the ground is raised, an unchanged depth does not automatically represent the same ground disturbance in the original soil.

Where road or ground elevations change, show the former surface, present surface and proposed excavation base in a clear section drawing. A laterally moved foundation also needs an unambiguous reference to the old investigation plan. Identify proposed excavation or fill by location. The drawing makes clear which additional ground volume still needs specialist assessment.

03

Including access roads and retaining walls

A changed garage may affect access, drainage or adjoining changes in ground level. Include the proposed ground works in the enquiry. For retaining wall foundations, describe the location and ground works depth separately. Assessment of the house does not automatically cover these additional tasks.

Also state which preparatory work is proposed for the new access road or retaining wall. Auxiliary pits, retaining structures and connections may extend beyond the final element’s outline. For staged construction, these ground works are assigned to the respective stage. Before the first ground disturbance, the parties can then establish whether existing results fit or a specifically defined addition is needed.

04

Keeping unchanged areas identifiable

A plan change does not make completed investigations worthless indiscriminately. Mark just as clearly which areas and depths remain unchanged. Existing results can then be used specifically and outstanding areas defined. Only on that basis should the necessary addition be determined.

Project documents

Documents that establish the next step

Showing the ground surface together with ground works depth

A depth in metres needs an unambiguous reference elevation. Show the former surface, the surface now planned and the respective base. Specialist planners can then compare which ground layers the existing result covers. Equal numerical depths measured from different starting elevations are not a reliable basis for assuming that the investigation task has stayed the same.

Keeping ancillary structures in the plans after a change

A relocated garage may involve changed access or drainage. Record the ground disturbance proposed for these, including foundations and working areas. Even where the main building stays within an area already assessed, additional structures may lie outside it. Showing them together helps clarify such areas specifically before commissioning and before the respective work.

For a newly added retaining wall foundation, identify location, foundation depth and working area separately from the house. Specialist planners compare this geometry with the earlier investigation plan. A part already covered adequately remains usable. An outstanding specialist question is related to the additional ground volume and the findings needed for its construction. Changes in construction method are communicated with their effects on the ground works. Where clearance work is carried out, its associated clearance record and the areas and depths covered are retained in the project file.

Construction sequence

Coordinate investigation and construction sections

Providing the plan comparison with the enquiry

Send the old and new positions with their associated section drawings. Add existing investigation reports and identify the first proposed ground works. The initial discussion can then address the actual changes. Depths or structural elements not yet decided are treated as outstanding planning information and considered when defining the brief.

Identify the activities to be carried out first, including their preparatory ground works. Where several parties are involved, it should be clear who maintains the current plan version and passes changes to site management. Newly known utilities, accessible sections and limitations are reported. An announced date is coordinated with the investigation scope actually clarified and prerequisites still to be met.

Coordinate the construction phase with us

Starting work from the agreed record

Before the affected ground works, site management receives the current plans and applicable results. If the location changes again, that version is compared anew with the investigation scope. Those involved must be able to identify which task has already been clarified and which addition remains outstanding. Earlier applicable findings remain available with their actual scope.

Coordinate the construction phase with us
Method selection

Select methods according to the task and survey conditions

Historical records and aerial photographs

Historical aerial photograph analysis relates photographs, maps, land-use records and earlier assessments to a defined investigation area. Dates and knowledge gaps remain identified. Where historical questions remain unresolved, the necessary research and analyses are actually carried out. For a moved excavation in Differdange, the assessment checks whether the new area lies within that considered at the time. An unchanged parcel name does not establish this relationship alone. Historical assessment remains distinct from technical investigation of the present ground. The outstanding questions derived from it enter investigation planning with the specific ground works.

Understand aerial photograph assessment

Magnetometric survey

Magnetometry passively records anomalies with a magnetic effect. An object’s conductivity alone does not determine its detectability by magnetometry. During alterations, existing reinforcement, utilities, fences and metal installations may affect the survey response. For a newly affected excavation area, its actual conditions are considered. Specialist planners justify suitability according to the investigation objective, ground volume required and expected objects. Measurement data and interference are interpreted together. A strong signal alone does not identify explosive ordnance. Sections covered, limitations and outstanding questions are recorded clearly in the report and associated plans.

Understand the scope of magnetometry

Electromagnetic methods

Transient electromagnetic methods, or TDEM, record the time-dependent electromagnetic response of conductive objects. Their suitability is justified for the required investigation objective and actual survey conditions. For an access road relocated later, paving, utilities and other installations may differ from conditions in the original excavation area. These differences inform method selection and interpretation. Measurement data receive a spatial reference. Interference and areas that cannot be investigated adequately remain identified. Supplementary investigation is derived from the outstanding technical question. Equipment availability alone does not determine the suitable approach for the additional ground volume.

Understand electromagnetic surveying

Ground-penetrating radar

Under suitable conditions, ground-penetrating radar can detect structures and reflections below ground. Ground composition, moisture, installations and the investigation objective affect interpretation. Professional interpretation relates the survey response to other findings. An anomaly does not automatically identify explosive ordnance; an unremarkable image remains specific to the ground volume actually investigated. When using an existing survey, its original brief, location and limitations are checked. Utility detection and geotechnical investigation retain their own purposes. For a changed foundation, this establishes what additional findings are needed and whether the method is suitable under the local conditions.

GPR and limitations

Deep-ground and downhole surveys

For a deeper excavation, retaining wall foundation or changed borehole position, clearly describe location, depth and reference elevation. If a suitable surface investigation cannot provide the findings needed, an agreed deep or borehole survey may be considered. Existing utilities and professionally prepared investigation access form part of preparation. A general depth in metres or standard grid does not replace this planning. Results or borehole clearance identify the investigation scope actually completed. Moved points and additional depths are compared against it. Luxembourg prerequisites for the specific specialist work are clarified before it begins.

Prepare deep interventions

Survey during construction

If a necessary preliminary investigation cannot be completed in full, the suitability of a professionally planned approach during construction is assessed. This may combine excavation in layers, specialist exposure and supplementary surveying in the respective work area. Visual observation alone during excavation is insufficient for detection. Interpretation and communication of findings form part of the proposed construction programme. For a changed garage or retaining wall, the additional area covered is clearly identified. Limitations and outstanding tasks remain documented. If ammunition is actually found, work is stopped and SEDAL or the police are notified; private specialist work retains its permitted scope clarified beforehand.

Agree the approach during construction
Technical assessment

From plan comparison to a justified investigation scope

Assess existing findings

The historical aerial photograph analysis and other earlier assessments should be available with their maps and limitations. Check the area to which the findings apply. A PAP describes the area’s planning; it does not replace such a technical report. Nor does being in a particular locality establish contamination of a specific site.

Tailor the survey to the new task

The surveying must be capable of providing the findings needed for the proposed ground works under the actual conditions. These include access, existing installations and possible interference. Where individual areas cannot be assessed adequately, those limitations must remain visible in the results. They do not establish general clearance for every later change.

Record the necessary steps

A clearance plan can clearly relate investigation tasks to subsequent ground works. This is particularly useful where different structural elements or changed elevations raise different questions. Responsibilities and permitted services require separate clarification for the Luxembourg project. An additional investigation step must be derived only from the specific need.

Next steps

Documents for your project in Differdange

01

Identify the locality and authoritative PAP

The municipal directory lists approved PAP for Differdange, Niederkorn and Oberkorn. For Mathendahl, a graphical and written section are provided. Identify the relevant plan and its version in your enquiry. The directory is a planning aid, not a register of sites investigated for explosive ordnance. The initial discussion establishes the project location and findings needed. Existing plans, statements and investigation reports are checked for currency, spatial reference, completeness and gaps.

02

Address outstanding historical questions

Where historical questions remain open, necessary research and aerial photograph assessments are actually carried out within the commission agreed by specialists. Existing assessments are considered with their respective subareas and conclusions. Additional findings are assigned to the present area of ground disturbance and used in investigation planning.

03

Include old and new section drawings

Section drawings can show how the building, road and ground levels change in relation to each other. Add the proposed excavation depths and known underground structures. If there is no final elevation plan, identify what remains undecided. An initial technical discussion should not rely on depths assumed to be settled. The suitable method is selected according to the investigation objective, ground works depth, ground composition, installations and actual survey conditions. Access and required prerequisites are clarified with the responsible parties.

04

Obtain the earlier investigation plan

The results documentation is needed with its area boundaries and limitations. An invoice or brief notice of completed work does not replace this documentation. Have missing appendices added where available. The comparison should show what has already been answered adequately and which questions remain unresolved.

05

Perform the agreed investigation

The agreed survey or appropriate investigation during construction is carried out on the defined areas and points. Measurement data and observations receive clear position and elevation references. Uninvestigated areas, restricted access and relevant interference are recorded.

06

Assess and document findings

The collected data and findings are assessed against the investigation objective and actual measurement conditions. The assessment takes account of interference and limitations. The report and plan appendices document the technical assessment, areas addressed and their position, elevation and depth references. Required further tasks follow from this.

07

Agree changes before ground works

If the plans change again after assessment, pass on the new version. Site management and specialist planners should establish before construction whether existing results fit. This also concerns connections brought forward and smaller additional foundations outside the excavation originally described. After assessment, the report and associated plans are handed to site management with the areas covered, limitations and outstanding tasks. The next-step decision for the following ground works is agreed on that basis.

Documentation

Account for Luxembourg responsibilities

Findings and their scope

FONTANA-EOD helps coordinate the investigation needed for your project in Differdange. The specific private scope of services and prerequisites required in Luxembourg are clarified before commissioning. German technical records are assigned to their respective evidential purpose. The responsible Luxembourg bodies make the decisions assigned to them; private reports document the agreed technical task.

Project responsibilities

Found ammunition falls within the responsibilities of the state SEDAL service. The Luxembourg Army identifies, among other tasks, identification, neutralisation and destruction. If an item is found, do not touch or move it and notify SEDAL or the police. An existing plan or earlier investigation does not replace this report.

Working approach

How FONTANA-EOD works

Document the agreed specialist service clearly

We assess the planned groundworks against the available documents and their design revision. Before attending site, we agree with you what needs to be investigated, which areas are accessible and what findings are required. If the design or site conditions change, we check whether the agreed scope remains appropriate. The report states what was actually investigated and the limits of the findings. This allows designers and site management to see which findings they can use and where questions remain.

Discuss the investigation task

The task before the equipment

We first establish the investigation objective: which question must it answer? We then select a technically suitable method. The availability of a particular device or experience on a similar neighbouring site is not enough to justify the choice of method on its own.

Keep limitations visible

Inaccessible areas and limited conclusions are identified. They do not disappear into a total area figure. Designers and site management can then decide specifically which areas still need attention and when a suitable survey becomes possible.

Clarify changes before intervening in the ground

A new location, additional depth or different construction method is compared with previous results. A familiar project name does not replace this comparison. Feedback is provided before the affected work so that an outstanding question can be included in the sequence.

Hand over the report and plan together

The technical conclusion remains connected to its location references and appendices. A brief summary helps orientation but does not replace the documented survey scope. This basis is retained even if site management or contractors change.

Where area clearance is required, the agreed specialist approach describes the objective, spatial scope and handovers. Permitted private activities remain distinct from SEDAL’s state responsibilities. Clearance work actually completed receives a clearance record identifying the areas covered and limitations. The report and associated plans are provided together for the project file.

Understand the results

Use technical statements for the next decision

Clearly identifying the reason for a change

Explain whether a move affects the building foundations, an access road or merely the drawing. This distinction helps assess the actual ground works. Alongside the new drawing, specialist planners need a clear assignment of the affected areas. This identifies the question added since the previously considered plans.

Understand investigation reports and their limitations

Retaining records when project participants change

Hand over the plan version used together with reports, maps and limitations. New site management should be able to follow the spatial comparison without assumptions. Brief notices can help orientation, but do not replace complete results evidence. Outstanding points retain their reason and affected structural element until the necessary findings are established.

Understand the service scope
Design and findings

Documents for the next construction decision

Illustration: aerial photographs and maps on two screens and printed on a desk.

Historical evidence and the current design

Aerial photograph interpretation is related to the actual groundworks. Its purpose and geographical scope remain distinct from a technical investigation of the ground as it is today.

Understand aerial photograph assessment
Illustration: two people review plans and documents at a table beside a construction vehicle.

Specialist reports for site management

The findings, their locations and limitations are handed over together. This makes clear to those carrying out the work which area has been investigated and which task remains outstanding.

Assess investigation reports
Four people in orange high-visibility vests in front of two excavators on a construction site.
Person with a yellow survey cart on a footpath in front of a hedge.
Questions from planning

Questions about changed construction plans in Differdange

Is the same parcel number enough to reuse a report?

No. The actual investigation area and its limitations must also match the new ground works. A moved building or additional connections may affect different areas even though the parcel number stays the same.

Why does depth information need a reference elevation?

So that the investigation depth can be compared with the depth of construction work. Where different ground surfaces are used as the starting point, equal depths in metres may refer to different ground volumes.

Does a change in elevation always require a new survey?

Not automatically. First check whether the existing findings still cover the changed ground works. This establishes whether additional records, supplementary assessment or further investigations are needed.

Does the Mathendahl report establish that the site is free from explosive ordnance?

No. The report of 25 April 2022 explains an amendment to development planning. Findings about actual investigation status require separate explosive ordnance reports and their appendices.

What should I do if I find a suspicious item of ammunition?

Stop the affected work. Do not touch, move or relocate the suspicious object, or expose it further. Leave the danger area and keep others away. From a safe distance, notify the Luxembourg police on 113 or SEDAL. Do not take the object to a police station or other official premises, or to a recycling centre. Follow the instructions of the responsible authorities.

Which plans show a change of position most clearly?

A comparison of old and new excavation positions with section drawings, vertical references and working areas. The investigation plans are included alongside them.

Which records does incoming site management receive?

Hand over the plan version used together with the complete reports, maps and limitations. Outstanding points retain their reason and affected structural element. A brief notice helps orientation, but does not replace traceable results evidence for the next ground works.

What affects the cost of an investigation in Differdange?

The work involved depends on existing findings, additional area and depth, the suitable method, access and interference. Preparatory work, interpretation, the report and associated plans are assigned to the investigation scope needed. For work in Luxembourg, the specifically required evidence, notifications and organisational prerequisites are considered. State handling of finds and privately commissioned project services are treated separately according to their respective purpose and responsibility for costs.

Project enquiry

Prepare the first technical discussion

Show the changes

Compare the old and new excavation with elevations and ancillary structures.

Add the project address, affected construction lots, working areas, proposed exploratory work and borehole positions. Explicitly identify undecided depths as outstanding planning information. State which findings are already needed and which details must be supplied before work begins. Utility plans and known official conditions also belong in the enquiry. Identify the responsible contact and intended start of each ground works activity.

Provide the results

Hand over reports with complete maps and limitations.

List historical analyses, technical results documentation and known official requirements with their dates. Provide the associated maps together. For work in Luxembourg, company credentials, service notifications and documents for posting employees are organised by their respective purpose. The parties clarify who will provide missing details and how the current status will remain available before work starts. A later plan change is clearly assigned to the reports affected.

GPR on a construction site
Project enquiry

Have your project assessed

Whether historical aerial photograph analysis, explosive ordnance surveying, surface surveying using GPR, magnetometry or TDEM, deep-ground surveys, downhole surveys, excavation supervision, area clearance or ordnance recovery is needed depends on the location, ground disturbance, depth, ground and existing documents. An early ordnance assessment provides clarity for tendering, programming, occupational safety and construction.

FONTANA-EOD combines its Section 7 SprengG licence, specialists holding Section 20 SprengG certificates of competence, suitable survey and clearance methods, and traceable documentation. Send the site plan, depth of ground disturbance, construction phase and existing documents for an initial technical assessment.

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