Legislation and guidance Hazardous substances consents (HSCs) are regulated by the Planning (Hazardous Substances) Act 1990 (P(HS)A 1990), the Planning (Hazardous Substances) Regulations 2015 (PHSR 2015), SI 2015/627 in England and the Planning (Hazardous Substances) (Wales) Regulations 2015 (PHSWR 2015), SI 2015/1597 in Wales. Nuclear installations and radioactive substances are governed by a separate set of statutory controls. The government in England has published Planning Practice Guidance (PPG) on hazardous substances, which explains planning controls relating to the presence of hazardous substances in England and how to handle development proposals around hazardous establishments. The Health and Safety Executive (HSE) has also published guidance on hazardous substance consents, including HSE’s role as a statutory consultee on applications for HSC. Purpose of hazardous substance consents The presence of a hazardous substance on, over or under land above a threshold quantity requires an HSC from the relevant Hazardous Substances Authority (HSA) who will usually be the local planning authority (LPA). Examples of hazardous substances include ammonium nitrate, bromine, chlorine, and natural gas stored in quantities above the threshold