Boundary & data map
Site-by-site inventory of energy, fuel, materials, water and waste flows. Reconciliation of 14 ERP instances into a single line-item dataset. Materiality assessment against ESRS double-materiality criteria.
ClientSTRABAG SE
SectorConstruction & Infrastructure
EngagementESG · Waste · IED permitting
Case 04 · 2024 · NDA
Auditing the footprint of 86,000 construction projects.
A Group-level ESG diagnostic across STRABAG's European operations — covering carbon accounting on 1,200+ active sites, waste-stream mapping under EU Circular Economy rules, and IED/IPPC permitting support for asphalt-mixing and concrete-batching plants. Delivered in 14 weeks.
The brief: prove ESG, waste and IED performance at construction-site resolution.
STRABAG operates one of the largest construction footprints in Europe — from Alpine tunnels to North Sea port expansions. By 2024, group management needed a single, defensible view of environmental and social performance across more than 1,200 active project sites and a tier-1 supplier base of over 8,000 companies.
The brief had four hard requirements. First, a Scope-1, -2 and -3 greenhouse-gas inventory aligned with the GHG Protocol and auditable against ISO 14064. Second, a waste-management diagnostic mapping the 71 distinct waste streams generated across demolition, earthworks, asphalt and concrete operations, with diversion pathways against the EU Waste Framework Directive. Third, IED / IPPC permitting support for 34 installations — primarily asphalt- mixing and concrete-batching plants — including BAT (Best Available Techniques) reference document (BREF) gap analyses. Fourth, a readiness review against the European Sustainability Reporting Standards (ESRS) ahead of the CSRD's first reporting wave.
Existing reporting covered the corporate layer well — but stopped at the site boundary. Site-level data was fragmented across 14 ERP instances, three subcontractor management systems, and project managers' local spreadsheets. The audit had to reach into that layer without slowing operations.
Detailed site data, supplier names and permit IDs are withheld under
NDA. This case describes methodology, structure of findings, and
measured outcomes at an aggregate level.
"We needed evidence we could hand to an auditor on day one — not a deck we'd spend six months defending." — Group CFO, kickoff briefing
Five phases, fourteen weeks.
A field-first methodology: data was collected at site level before being reconciled at group. The audit team embedded with STRABAG's sustainability, environment and permitting functions to keep the work close to operational reality.
Site fieldwork
42 site visits across DACH, CEE and Nordics. On-site measurement of Scope-1 emissions, waste-segregation audits, and worker interviews on safety, working hours and grievance channels.
Waste-stream diagnostic
Mapping of 71 waste streams across demolition, earthworks, asphalt and concrete operations. EWC-code classification, hazardous-waste screening, diversion pathways against the EU Waste Hierarchy.
IED / IPPC permitting
Permit review for 34 IED installations — asphalt-mixing and concrete- batching plants. BAT-AEL benchmarking, BREF gap analysis, emissions- monitoring plan per Annex VI.
Consolidation & reporting
Group-level GHG inventory reconciled to ISO 14064. ESRS gap analysis with a roadmap to first-wave CSRD disclosure. Findings presented to the Audit Committee and Supervisory Board.
What the audit actually found.
Three findings recurred across regions: a structural under-reporting of Scope-3 category 1 (purchased materials), a material gap in waste classification at the site-perimeter, and inconsistent BAT-AEL alignment across the IED installations.
Environmental
4.2 Mt CO₂e
Group-wide inventory, FY2023, baseline year
- Material gap in Scope 3Category-1 (purchased steel, cement, asphalt) accounted for 68% of inventory but had 41% data coverage.
- Fuel data qualityDiesel and gas-oil readings were 3× more accurate from telematics than from purchase-ledger reconciliation.
- IED stack-monitoring drift14% of continuous emissions monitoring systems (CEMS) on asphalt plants had >5% deviation from BAT-AEL ranges.
Waste
71 streams mapped
Across demolition, earthworks, asphalt and concrete
- Excavation spoil misclassified31% of sites coded inert excavation spoil as "waste", inflating diversion KPIs and breaching EU Waste Framework Directive guidance.
- Hazardous fraction under-countedAsphalt millings and contaminated soil were treated as inert in 19% of sites; the true hazardous share is ~2.3× higher.
- Backfilling loopholeRecovered concrete fines were routed to backfilling without Article 5 by-product verification, in 4 of 11 CEE countries.
Governance
34 permits reviewed
IED installations across asphalt, concrete and bitumen
- BREF gap22 of 34 installations were operating against pre-2018 BREF baselines; the cement and lime BREF update had not been incorporated into permit conditions.
- Permit renewal queue7 installations had permits older than 5 years without a review under Article 21(3) of the IED.
- No group-level permit registerPermit data sat in 6 different national systems with no consolidated view — now built.
What we handed over.
Eight artefacts, designed to survive a CSRD assurance engagement and usable by site managers without analyst support.
- 01
Group GHG inventory
ISO 14064-aligned, Scope 1-2-3, with methodology file and uncertainty analysis per category.
PDF · XLSX - 02
Waste-stream register
71 streams with EWC codes, hazardous-screening flags, and diversion pathways under the EU Waste Hierarchy.
PDF · DB - 03
IED permit pack × 34
Permit review files with BAT-AEL benchmarking, BREF gap notes, and emissions-monitoring plans per Annex VI.
PDF · secure - 04
Group permit register
Consolidated register of 34 IED installations across 6 national systems, with renewal-due dates and BREF versions.
DB · GIS - 05
ESRS gap analysis
Line-by-line readiness assessment against the 12 ESRS standards, with remediation roadmap to FY25.
PDF · tracker - 06
Site audit dashboard
Power BI layer over ERP data: per-site KPIs on emissions, waste, hours, grievances, supplier risk.
BI workspace - 07
Audit-committee pack
20-slide narrative deck with the seven decisions the committee needs to make, and a one-page evidence map.
PDF · Keynote - 08
Fieldworker toolkit
Updated site-manager handbook, waste-segregation posters in 11 languages, and weekly KPI capture template.
Print · digital
Twelve months on, what changed.
The audit closed in Q1 2024. The numbers below are measured at Q4 2024 — one full operational cycle after the recommendations entered the planning round.
+47%
Scope-3 category-1 data coverage, from 41% to 60% of material spend.
GHG inventory · FY24 vs FY23
−18%
Misclassified excavation spoil reported as "waste" after the EWC-code review and reclassification programme.
Waste register · Q3 2024
28/34
IED installations re-baselined against current BREFs, with the remaining 6 scheduled in the FY25 permit-renewal cycle.
Group permit register · Q4 2024
CSRDready
First-wave disclosure signed off by the Audit Committee, ahead of the FY25 deadline.
Audit Committee · Dec 2024
