Technical map of the Lower Bavaria administrative district showing Landshut for explosive ordnance assessment and surveying by FONTANA-EOD

Explosive ordnance surveying in Passau

Before a new building, ground works often begin with removing old foundations, basements or utilities. FONTANA-EOD helps project owners, designers and site managers in Passau compare this ground disturbance with existing explosive ordnance documents. Send the demolition plan, new ground disturbance depths and complete reports so the specialist services needed can be identified before the affected works.

Demolition

Show below-ground structures on the plan.

Groundworks

Clarify the first ground disturbance in good time.

New construction

Compare results with the design.

Discuss the project's technical requirementsExplosive ordnance investigation in Bavaria
Assess the construction project

When does demolition belong in explosive ordnance planning?

As soon as it may affect ground volumes, for example when removing foundations, basements or utilities. Describe these works before demolition and provide existing plans and reports. Specialist planning coordinates necessary prerequisites and investigations with the proposed sequence. Preparatory ground disturbance also receives a clearly defined scope.

Project references

Selected project examples

Project site

Connect the site with the specific construction task

Map of Bavaria with a blue-and-white lozenge shield and crown, a tablet, white FONTANA-EOD helmet and notebook.

Prepare demolition and new construction with the right documents

The explanatory statement for Nibelungenstraße provides for explosive ordnance investigation before all ground works and addresses other ground-related questions separately. Your project needs its own requirements and later reports. The city's building advice service allows property-specific plan inspection; the investigation also relates to the actual demolition and new construction works. Passau is an independent city in Lower Bavaria and belongs to the Free State of Bavaria. Distinguish the city area from the district of Passau. State the address, cadastral plot and design version in the enquiry. The city's building advice service provides property-specific planning information to those entitled to receive it. For a property outside the city, municipal responsibility follows the actual project location. Further areas are listed in the regional overview; assign reports and planning requirements to the property and work step concerned.

Bavaria
Local context

Passau's war damage and preparation for present-day ground works

Investigation before ground works in the Nibelungenstraße plan

The explanatory statement for the “Nibelungenstraße” land-use plan in Passau describes redevelopment of the former police site at Nibelungenstraße 17. Because of possible unexploded bombs, it provides for investigation of the area before all ground disturbance. The plan addresses specialist supervision for possible contaminated land and geotechnical investigation separately.

The city brochure from September 2025 describes the air raid of 18 April 1945 and artillery fire from 29 April. It also documents demolition of Danube bridges, the Inn bridge and railway bridge over the Inn towards the end of the war. These local events form part of the historical background. For explosive ordnance assessment, compare earlier uses and wartime impacts with the specific areas, later earthmoving and existing investigation results. For present-day assessment, use the findings for the property and changes documented since.

Divide demolition into specific work steps

This sequence matters for preparation: demolition of above-ground buildings and removal of foundations are different work steps. Clarify in advance which disturb the ground and which conclusions must be available for them. The specific planning note is not an investigation report and establishes neither the site's current clearance status nor conclusions about other properties in Passau.

The later administrative record includes the decision adopting the plan dated 27 January 2025 and the subsequently published building permit dated 27 January 2026 for housing on the former police site. These notices concern planning and building law. Explosive ordnance planning also needs the actual investigation reports and results plans. The project owner provides these with the current demolition or new construction plan. This allows usable conclusions and specialist work still needed for the next construction phase to be identified. The public notice from 2026 summarises the permit and its conditions only briefly. The complete permit documents therefore also belong in the project file for construction.

Working together

Roles and responsibilities at the location

Client and operator

The client describes the project and provides the available project records. The operator adds requirements for use, access and timing. A coordinating contact brings the parties together; individual tasks remain assigned to the named parties. Before commissioning, it is clearly recorded what information is missing, who will obtain it and what decision the result is intended to prepare.

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. Requirements and decisions of public authorities are addressed with the responsible bodies. The documents needed for a particular procedure depend on the location and project. The technical report describes the work carried out, including its documented area, depth and scope. Decisions reserved for public authorities are made by those authorities.

In Bavaria, municipalities generally provide local hazard response as public safety authorities. Where urgent action is needed, the police take the necessary measures. The explosive ordnance disposal service commissioned by the Interior Ministry supports response to specific hazards from legacy ordnance that has been found. The München disposal unit is responsible for Lower Bavaria. Prepare project-specific research and property investigation as separate specialist commissions. Distinguish these private services from the commissioned service's activities involving legacy ordnance that are free of charge under the Bavarian notice.

Investigation task

Which specialist task comes next?

Define investigation and preparation together

Specialist planning considers the specific question and existing site conditions. Describe necessary preparatory measures with their own prerequisites. A suitable method must provide the conclusions needed under the actual conditions. Document remaining limits and consider them in further planning before ground works rely on those conclusions.

Compare suitable specialist services

Commission contaminated land supervision and explosive ordnance services appropriately

Both tasks may concern the same construction section but have different investigation objectives. Clarify their respective services and handovers. A commission concerning soil reuse or contaminants does not automatically include explosive ordnance assessment. For construction, assign the conclusions needed to the relevant technical tasks, responsible parties and construction phases.

Compare investigation methods
Project types

Prepare demolition and new construction according to their respective ground disturbance

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

Clarify earlier history before the first earthworks

Plans of existing structures and historical records help assess the tasks on a developed property. Include existing investigation reports with maps. Specialist planning considers proposed demolition and new construction areas together. Available findings remain usable while areas and questions still unresolved are explicitly identified for further preparation.

Obtain documents on earlier buildings and alterations actually carried out. An older basement plan may show different dimensions or elevations from the present survey. Additions and plans of disused connections also help comparison. Specialist planning assigns this information to the proposed work areas. Unknown routes are recorded as outstanding points. The investigation commission can then address the conclusions needed while considering the limits of the available documents.

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

Match the investigation sequence to construction phases

Buildings, hard surfacing and below-ground structures may affect access and measurement conditions. Describe what will remain and what will be removed. Coordinate the specialist services needed with these work steps. Restricted access does not justify a general instruction to expose the ground concerned without appropriate prior clarification.

During demolition in stages, working spaces and surfaces change. Describe the proposed construction stages and associated ground disturbance in the same programme. Agree with a specialist which preparatory works are possible under which conditions before they begin. In the tender, assign the investigation task, documents to be provided, access and results handover to the parties involved. Unresolved conditions can then be discussed before contract award rather than only becoming apparent when a separate commission begins.

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

Hand over results for the next ground disturbance

After each agreed specialist service, it should be clear which areas and depths were addressed. The site management team receives the complete results and remaining limitations. Compare further ground works with these. A completed demolition phase does not alone establish the investigation scope for a later larger or deeper excavation.

The results plan shows the relationship between the area investigated and forthcoming ground disturbance. If the excavation expands or a foundation is deeper, identify the additional task. Investigation boundaries remain clear after organisational handover of the site too. Contractors receive the current plan version with the associated reports. For outstanding sections, agree the subsequent service needed before ground disturbance there. Usable earlier results remain part of the project file.

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 reliable programme distinguishes tasks already technically resolved from prerequisites still outstanding. If an area will be only partly accessible, account for this when commissioning work. Results handover and assessment also need time in the construction programme. Agree timing and the work required once scope, access, documents, construction conditions and the date a decision is needed are clarified.

Discuss the scope and schedule
Tasks at the site

Where demolition already disturbs the ground

01

Record foundations and basements

Draw which below-ground structures will be removed and how deep the works extend. Old building plans may help; keep unknown areas clear in the commission. The term building demolition is insufficient to describe the actual ground disturbance. Agree necessary prerequisites with the specialist designers before these works begin.

02

Include utilities and hard surfacing

Disused connections, shafts or hard-surfaced yards may be worked on before the new building itself. Include these items in the programme. An investigation commission planned later for the main excavation does not automatically cover earlier ground disturbance elsewhere. Early separate commissions also need clear area and depth references.

03

Plan access and investigation together

A developed property cannot immediately be fully investigated under every condition. Existing structures and interfering materials may affect measurements. This is not an instruction to expose the ground yourself first. Describe existing conditions with plans and photographs so technically appropriate preparations and the necessary investigation can be coordinated.

04

Answer different ground-related questions separately

Contaminated land, bearing capacity and explosive ordnance concern the same construction ground but need different technical conclusions. A chemical finding does not replace explosive ordnance assessment. Conversely, an explosive ordnance report does not establish permitted soil reuse. Record which report answers which question and for which work step it is needed.

Project documents

Documents that establish the next step

Distinguish above-ground and below-ground works

The general term demolition may include activities with different effects on the ground. Draw foundations, basements and connections separately where known. Identify missing details. Necessary specialist planning can then address the actual ground disturbance rather than relying on an incomplete description of building demolition.

Include early separate commissions

Removal of a shaft or connection may be commissioned before the new building. These activities still belong in the common ground disturbance overview. State their locations, depths and dates. Necessary clarification takes place before each work; a later investigation commission does not automatically cover preparatory ground disturbance retrospectively. After clearance work actually carried out, the clearance record documents the areas addressed, methods, findings and remaining tasks. Assign this evidence to the relevant commission and its actual spatial scope.

Construction sequence

Coordinate investigation and construction sections

Provide the demolition plan for the initial discussion

Supply the proposed work steps with plans of existing structures and investigation results. Mark unclear areas and proposed deeper ground disturbance. This identifies the further information needed. An enquiry can also be made with incomplete documents, provided their limits are openly identified and resolved specifically later.

Coordinate the construction phase with us

Check the transition to new construction again

Compare the later excavation and its connections with the documented scope of earlier specialist services. Identify additional areas and depths clearly. Give the site management team the current plan and assigned reports. Agree additional investigations for outstanding tasks before each ground disturbance.

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 assessment and other old records help place the basis for suspicion in its spatial context. The available images, their evidential value and the limits of the area considered matter. The absence of an identifiable indication must be distinguished from a technically surveyed ground area. The assessment is considered together with the planned intervention and other available findings. It can support the choice of a survey, but is not a measurement of the present-day subsurface or confirmation for all future works.

Understand aerial photograph assessment

Magnetometric survey

Magnetometric methods detect magnetic anomalies. Whether they can address the specific survey task depends, among other things, on the expected objects, ground conditions, interference and required survey area. Fences, utilities or existing structures may affect interpretation. A measurement signal is therefore not described as ordnance solely because of its strength. Method, interpretation and any further investigation are planned as a connected specialist task.

Understand the scope of magnetometry

Electromagnetic methods

Electromagnetic investigations can be suitable for particular metallic targets and site conditions. Their suitability must be explained for the task, rather than inferred simply from the availability of equipment. Interfering installations, accessible areas and the findings required must also be considered. Results are documented with their location and survey conditions. The specialist assessment determines whether a supplementary method is needed; this remains a project-specific decision.

Understand electromagnetic surveying

Ground-penetrating radar

Under suitable conditions, ground-penetrating radar can provide information about subsurface structures and reflections. Ground conditions, moisture, installations and the particular survey task affect interpretability. An anomaly is not automatically ordnance, and an area with no apparent anomalies is not general evidence for arbitrary depths. The specialist interpretation and its limits are documented with the instruction. A survey for another purpose is not adopted without checking as ordnance evidence.

GPR and limitations

Deep-ground and downhole surveys

For deeper groundworks, it may be necessary to establish whether a surface investigation can provide the required findings or another approach is needed. Preparation includes the location, depth, borehole layout and existing services. Creating access for the investigation must also be properly planned by specialists. A general depth figure or standard grid cannot replace that work. Findings remain limited to the areas actually investigated and the method used.

Prepare deep interventions

Survey during construction

If a necessary preliminary investigation cannot be completed, the specialists assess whether a planned approach during construction is suitable. This includes coordinated investigation, interpretation and communication of findings within the intended work sequence. Visual observation of excavated material is not an interchangeable substitute for a necessary survey. Site management needs a clear description of when specialist work will take place, how new findings will be handled and which areas remain unresolved.

Agree the approach during construction
Technical assessment

Coordinate the necessary measures with demolition

Establish the historical background

The Historical aerial photograph analysis may provide indications of possible wartime impacts together with other records. Include earlier investigation reports too. The objective is a traceable assessment of the proposed construction area. A note in a land-use plan alone determines neither the technical method nor the scope of every later measure.

If underlying information is incomplete, the necessary Historical aerial photograph analysis is brought together with other available files and land-use information. Include earlier investigation reports with their maps and appendices. The assessment distinguishes indications of wartime impacts from specialist services already performed. Consider later ground changes and demolition where documented. The resulting question determines which areas need further technical investigation. Gaps that cannot be resolved remain clear for further planning.

Plan the investigation under existing conditions

The Surveying must fit the question and actual access. Different construction phases may need consideration. Clarify which results are needed before removing below-ground structures and how remaining areas will be addressed. Measurement limits belong in the documentation and must remain clear to contractors.

For the Surveying, consider expected targets, ground composition, structures and the depths needed together. Metal debris, utilities and remaining structures may affect measurements or interpretation. For deep localised ground disturbance, clarify whether the proposed method covers the ground volume required. Any necessary deep survey or borehole clearance receives a defined location and depth reference. Describe access and necessary preparations with their technical prerequisites.

Define the work sequence

A Clearance plan can relate necessary investigation and clearance services to demolition and new construction. It assigns measures to the relevant ground disturbance. Observation during excavation alone does not replace a required prior investigation. Separate methods during construction require specialist assessment and suitable conditions; agree their sequence for the specific ground disturbance.

The agreed Excavation supervision connects suitable specialist work with the proposed sequence. Give necessary investigations and area clearance where applicable a defined spatial and technical scope. For any necessary Ordnance recovery, agree access and protective measures with the responsible parties. If a suspicious object is encountered, keep the affected works stopped and notify the police immediately. Their instructions determine the next steps. Document services performed with findings, assessment and remaining limits.

Next steps

What to compile for an enquiry in Passau

01

Compare existing structures and proposed ground disturbance

A location plan, existing structure plans and sections of the new building are helpful. Mark structures to be removed in advance too. If depths or utility routes remain unknown, identify these gaps. An initial technical discussion can then take place without treating unclear details as a settled design. Record the project location, construction task and technical decision needed in the initial enquiry.

02

Identify the land-use plan for the property

Passau's city planning department offers property-specific building advice and inspection of existing preparatory and binding land-use plans. The address and cadastral plot help identify the documents. Obtain relevant explanatory statements and appendices alongside the plan drawing. General planning information is distinct from the project's separate explosive ordnance assessment. Document review includes complete explosive ordnance reports and their appendices. Where underlying information is incomplete, carry out historical research and aerial photograph analysis.

03

Look for later reports relating to planning notes

A land-use plan may propose an investigation that has since been completed. Ask for the actual reports with maps and limitations. These documents may be usable for further planning. If the final report is missing, a planning note must not be treated as proof of investigation completed. Method selection considers targets, ground conditions, interference and required depth. The agreed surveying or suitable supervision addresses the defined scope; findings and measurement limitations receive specialist assessment.

04

Confirm the work scope before starting

The site management team needs existing results clearly allocated to each ground disturbance. If basements, the excavation or connections are designed differently, compare the changed scope. Give the current version to everyone involved. Outstanding areas and depths must remain distinct from sections already assessed. The report and results plans document the services performed. The next decision determines further specialist needs before the affected subsequent ground works.

The project file includes the investigation report, location plans, assessment and documentation of clearance work performed. A clearance record documents its actual scope. After ground surface changes, the elevation reference used remains important for interpreting depths correctly. For the transition to new construction, compare these records with the current excavation, new connections and preparatory investigation points. Obtain missing appendices specifically. The subsequent technical decision identifies the additional work needed before the next ground works.

Documentation

Commission investigation and report a find correctly

Findings and their scope

The Bavarian notice dated 13 August 2026 distinguishes project-specific preliminary investigation from hazard response involving legacy ordnance that has been found. Private specialist contractors carry out the commissioned property investigation. Local hazard response generally lies with the municipalities. Report an actual find to the police immediately.

Project responsibilities

FONTANA-EOD supports coordination of the specialist services needed for your Passau construction project. The BFR KMR describe principles for planning, investigation and documentation. They apply directly to federal properties. For a private project, clarify the specific requirements separately; they do not establish a general additional investigation duty for every property.

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.

Understand the results

Use technical statements for the next decision

Identify the first ground disturbance clearly

The main excavation may appear late in the construction programme even though utilities or foundations will be worked on earlier. Record these earlier tasks. Clarify which technical conclusions must be available for each. This relates preparation specifically to the actual construction sequence.

Understand investigation reports and their limitations

Look for later reports relating to older planning notes

A planning statement may propose a service that has since been carried out. Obtain the existing results documents with maps and limitations. The planning note alone does not prove that the work took place. For present-day works, compare and document the actual investigation status with the proposed ground disturbance.

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 demolition and redevelopment in Passau

Should explosive ordnance assessment begin only after demolition is complete?

Removing foundations or utilities may itself disturb the ground. Clarify beforehand which conclusions each work step needs and how investigation and demolition fit together under existing conditions. The process combines document review, necessary historical research and method selection with investigation or suitable supervision, assessment and documentation.

Does the Nibelungenstraße plan establish completed clearance?

No. The explanatory statement contains an investigation note for the specific planning area. The actual investigation status needs the investigation and results documents prepared later. They do not support a city-wide conclusion.

Is supervision for contaminated land also sufficient for explosive ordnance questions?

No. The specialist services have different objectives. Contaminated land supervision does not replace a necessary explosive ordnance investigation. Both tasks must be included in the construction sequence and commissioned with their respective scopes.

Can I enquire even if basement or utility plans are missing?

Yes. Send the documents available and identify missing details. Describe the proposed works as precisely as possible. The additions needed can then be agreed with a specialist.

What should I do if I encounter a suspicious object?

Stop work, do not touch or move the object, and keep other people away. Notify the police immediately from a safe distance on 110 and follow their instructions. The municipality carries out its local public safety tasks; the police and commissioned explosive ordnance disposal service carry out their respective hazard response tasks.

Which factors determine the cost of explosive ordnance assessment?

Research needs, area and depth, access, structures and metal interference affect the work required. Further factors include the appropriate method, interpretation and documentation and, where necessary, investigation of findings. Usable earlier reports help limit the additional commission to the questions still unresolved. Coordinate the specialist services needed with the actual demolition and new construction phases.

Must an area difficult to access be exposed before making an enquiry?

Do not do this yourself as a prerequisite for the enquiry. First describe existing structures and access problems with plans and photographs. Specialist planners and the parties involved coordinate appropriate preparations and necessary investigations before these themselves disturb the ground. Structures and interfering objects may limit measurements and interpretation; explain the achievable result for the actual conditions.

What needs checking when moving from demolition to new construction?

Whether existing results cover the new construction area and depth, and which additional specialist services are still needed.

Project enquiry

Prepare the first technical discussion

Describe demolition

Draw below-ground structures and early ground works. Add the cadastral plot, plan version and known gaps in records of existing structures.

Relate the sequence to results

Provide dates, depths and existing reports together. Assign the reports to the proposed work locations and identify the date a decision is needed for the next construction phase.

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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