HIA vs EIA Heritage Chapter: When Each Is Required
If the proposal is EIA development under the EIA Regs 2017, the heritage impact is presented as a chapter of the Environmental Statement, not as a standalone HIA. The chapter follows the CIfA-IEMA 2021 Principles of Cultural Heritage Impact Assessment. For non-EIA development, a standalone HIA is the right vehicle. The two approaches can share underlying significance and impact analysis, but the document architecture differs.
When EIA applies
The Town and Country Planning (EIA) Regulations 2017 catch projects listed in Schedule 1 (mandatory) or Schedule 2 (screening) where significant environmental effects are likely. Heritage is a Schedule 4 information requirement: every Environmental Statement must include 'a description of the material assets and cultural heritage' affected. For Schedule 2 projects, the LPA screens; for Schedule 1, EIA is automatic.
What the EIA Heritage Chapter contains
- Baseline conditions, designated and non-designated assets in the study area.
- Methodology, sensitivity-and-magnitude matrices per CIfA-IEMA 2021.
- Assessment of construction-phase, operational-phase and cumulative effects.
- Mitigation hierarchy, avoid, reduce, remedy, compensate.
- Residual significance of effect after mitigation.
Can an HIA be re-used as an EIA chapter?
Partially. The significance assessment and the descriptive elements transfer. The impact-evaluation framework usually has to be rewritten in EIA terminology (sensitivity, magnitude, significance-of-effect matrix). The mitigation hierarchy needs to be expressed in EIA conventions. Allow approximately 30 to 50% additional consultant time for the chapter format over the HIA equivalent.
Who writes the chapter
Usually a heritage consultancy with EIA experience, working as a sub-consultant to the lead EIA consultant. CIfA-Registered Organisations and IHBC firms with EIA-chapter track record are the typical instructions.