Budgeting a hazardous substances consent application

A hazardous substances consent application is cheaper than most applicants expect on the fee side and dearer than they expect on the evidence side. The fee is a flat sum set by regulations, not scaled to tonnage or site area. The hazardous substances consent cost that decides your budget is the technical work behind the form: a substance inventory, a plan showing where each quantity will sit, and enough process detail for the regulator to judge what a release would do to the people around you.

Consent is a separate permission from planning permission. You can hold one without the other, and a new storage installation usually needs both.

When consent is needed

Consent is required under the Planning (Hazardous Substances) Act 1990 where a hazardous substance is, or is to be, present on, over or under land at or above its controlled quantity. The substance list and the controlled quantities sit in Schedule 1 to the Planning (Hazardous Substances) Regulations 2015. Stay below the controlled quantity for every listed substance and no consent is needed, however unpleasant the material is to handle.

The duty attaches to presence rather than to use. A distributor keeping drums in a yard is in the same position as a manufacturer feeding the same substance into a process. Pipelines and tanks above and below ground count.

Consent attaches to the land, and the Act treats a change in the person in control of part of the site as a trigger for revocation unless an application to continue the consent is made. That matters on sale, on a lease of part of a yard, and on a group reorganisation that moves the operating company. The continuation application is a small piece of work and an expensive one to forget.

Controlled quantities and how they are counted

The thresholds in Schedule 1 are quantity-based and substance-specific, and they are aligned with the lower-tier qualifying quantities used in the major accident hazard regime. Two traps catch people.

The first is aggregation. Quantities of substances in the same hazard category are added together under the rules in the Schedule, so three separate tanks, each comfortably below the individual figure, can still take the site over a category threshold.

The second is the maximum rather than the average. The relevant quantity is the amount that may be present, which is normally the design capacity of the vessel or the maximum stock the operation is set up to hold, not the stock sitting there on the day you measure. Build the consent around the worst case you will ever run, because a consent pitched at today's throughput becomes an obstacle the first time a supplier changes delivery sizes.

What the application has to contain

The regulations prescribe the form and content, and the substance of it is a technical schedule rather than a planning narrative. Expect to supply:

1. The name and the Schedule 1 category of each hazardous substance, with the maximum quantity sought for each.
2. A site plan at an identified scale showing the boundary, and a separate plan or plans showing the location of each vessel, store or pipeline with the quantity held at each point.
3. A description of how each substance is kept and used, including vessel type, capacity, pressure, temperature and bunding.
4. The ownership certificates and the notice to anyone else with an interest in the land.

The expensive part of that list is the third item. A process safety engineer or a competent process chemist normally writes it, because the regulator reads it as a description of containment and failure modes rather than as a specification. If you brief that person from an existing plant description you already hold, the cost falls sharply. If they have to work it up from drawings, it does not.

The regulator's role and the consultation zones

The hazardous substances authority is normally the district or unitary council, with exceptions named in the Act, and the Health and Safety Executive is consulted on the application. The HSE assesses the consequences of a release and advises the authority. It also maintains the consultation distances around consented sites that then shape what the authority can approve nearby.

Those zones are the real commercial consequence of a consent. Once a site holds consent, the HSE advises on development proposed within the consultation distance, and the advice is graded by the sensitivity of the proposed use and its distance from the source. A housing scheme on the adjoining field becomes harder, and the owner of that field will notice. If you are the one buying land near an existing consented site, check the position before you exchange, not after.

The Environment Agency is consulted where there are water or pollution implications. None of this replaces an environmental permit, a COMAH safety report or the duties under the fire safety legislation, all of which run on their own timetables and budgets.

Conditions and what they cost you later

Conditions on a hazardous substances consent are tighter and more literal than planning conditions. They typically fix the maximum quantity of each substance, the location at which it may be kept, and the type and specification of the containment. Some fix the form in which a substance may be held, for example a solution of a stated concentration rather than the concentrate.

The practical effect is that an operational change which would be invisible in planning terms can breach the consent. Moving a tank twenty metres to free up yard space, swapping to a larger IBC, or taking delivery in a stronger concentration all touch conditions that name a figure. Each of those needs a fresh application or a variation, with its own fee and its own eight-week clock.

Build headroom into the original application. It costs nothing extra in fee terms to apply for the quantity you will realistically need in five years, provided the HSE can still advise acceptably on the consequence distances.

Fees, timescales and the shape of the budget

The application fee is prescribed and flat, so check the current figure in the regulations before you budget rather than carrying over a number from an earlier project. The standard determination period is eight weeks from a valid application, which can be extended by agreement, and publicity and consultation run inside it.

A realistic budget for a single-site consent on an existing industrial unit has four lines, and only one of them is the fee.

Where a new building, tank farm or extraction plant is also proposed, the planning application runs alongside and brings its own evidence. That is where a Planning Statement and, for a site near sensitive receptors, air quality and noise work come in. Our note on what a planning agent's fixed fee includes sets out where the boundaries of an agent's scope normally sit, which is worth agreeing in writing when two consent regimes run in parallel.

One more budgeting point. If part of the site has operated above a controlled quantity without consent, deal with that first and take advice on it, because the enforcement route is not the same as the planning one. The lawfulness question for planning purposes is handled through a certificate, and our guide to budgeting a lawful development certificate application explains that cost separately.

Before you commit, read the Schedule 1 entries for your substances and write down the maximum quantity for each. That single sheet tells you whether you have a consent application at all, and it is the thing your engineer will ask for first. If you also need the planning documents that sit alongside it, browse the 66 PlanScope report types and start with the Planning Statement.

This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. For specialist technical reports, qualified professional input may be required.