Quarry audit.
Independent stockpile verification for auditors.
RICS-regulated third-party verification of quarry operator stockpile and extraction volumes — commissioned by external auditors to support year-end inventory assertions for publicly-listed aggregates, minerals and stone groups.
Third-party stockpile verification for the year-end audit.
A quarry audit is an independent verification of a quarry operator’s own stockpile and extraction volume figures, commissioned by the external auditor of a publicly-listed aggregates, minerals or stone group. Stockpile inventory sits on the balance sheet as a material asset and external auditors need independent, RICS-regulated, third-party evidence before signing off the financial statements.
Angell Surveys reviews the operator’s aerial survey methodology, independently re-computes a sample of stockpile volumes from the source imagery or point cloud, performs variance analysis against the operator’s reported figures, and documents any exclusions or reconciliations. The deliverable is a Final Report issued to the audit firm for inclusion in their year-end working papers.
Angell Surveys is a RICS-regulated practice (Firm 681790). Audit engagements are conducted by an MRICS Chartered Civil Engineering Surveyor with no commercial relationship to the audited operator — the independence the auditor requires.
What the audit covers.
Methodology Review
Review of the operator’s aerial survey methodology — sensor and platform, GCP control density, processing software, reference surface definition and accuracy reporting against measured residuals.
Independent Volume Calculation
Independent re-computation of each sampled stockpile volume from the source imagery or point cloud using Angell’s own software stack and reference surfaces — not a re-read of the operator’s spreadsheet.
Variance Analysis
Documented percentage variance between operator and Angell-verified figures for each stockpile, banded by materiality so the auditor can flag the ones that move the needle on the inventory line.
Reconciliation & Exclusions
Reconciliation of stockpiles present in the auditor’s schedule but missing from the operator’s list (and vice versa), plus documented exclusions where geometry, base definition or capping incorporation make a defensible volume impossible.
Final Report
Group-level executive summary, per-site sub-reports with photographic and computational evidence, and a methodology appendix — issued in PDF with revision control until the auditor signs the engagement closed.
Multi-Site, Multi-Year
Group estates audited as a single engagement, with continuity of methodology year on year so the auditor can compare like-for-like across reporting periods. Sample sizes adjusted to the audit firm’s materiality and risk profile.
Why an independent surveyor.
The independence the entity’s own measurements cannot satisfy.
Independence — RICS-regulated, no commercial relationship to the audited operator.
Audit-trail evidence — per-stockpile working papers ready for the audit file: input data references, computational steps, photographic evidence, documented variance.
RICS standards — every finding referenced against the RICS Measured Surveys of Land, Buildings and Utilities (3rd edition) accuracy bands. Published framework, not subjective opinion.
Engagement continuity — multi-year engagements compare current-year findings against prior-year baselines on a like-for-like basis.
Confidentiality — NDA-covered. Operator data, site names and figures remain confidential to the audit team and the audited entity.
Why your auditor brings us in.
Material balance-sheet item — stockpile inventory sits as a material asset on the balance sheet of any publicly-listed aggregates, minerals or stone group. Misstatement affects reported financial results.
External audit cannot rely on self-assessment — auditors cannot accept the audited entity’s own measurement as sole evidence for the inventory line. Independent verification is required by audit standards.
RICS-regulated, not operationally conflicted — Angell Surveys holds no minerals-extraction, aggregates-trading or operational interest. Our only deliverable is the audit report to the audit firm.
Methodology improvement — methodology findings flow back to the operator as recommendations for subsequent years, not just the year being audited.
How it works.
From audit-firm brief to filed working papers — a documented five-step engagement under NDA.
Audit Firm Brief
Audit firm’s corporate-capital-markets team commissions Angell ahead of the year-end cycle. Scope, sample and materiality agreed in writing.
Data Receipt
Operator aerial data — imagery, point cloud, stockpile list, reference surfaces — provided via secure transfer under NDA. Chain of custody documented.
Independent Compute
Per-stockpile volumes computed in Angell’s own software stack against documented reference surfaces. Operator figures held back from the calc until completion.
Variance & Findings
Variance analysis, methodology findings, reconciliation of operator vs auditor schedule differences and documented exclusions assembled into draft reports.
Final Report
Draft issued to the audit team for query. Revisions resolved until the engagement is signed closed. Final revision is filed into the audit working papers.