Environmental Statement further information and its cost

A request for further information on an Environmental Statement is the most expensive event in the life of an EIA application, and the cost is rarely the consultant's re-drafting fee. It is the programme. Under regulation 25 of the Town and Country Planning (Environmental Impact Assessment) Regulations 2017, an authority that considers the statement inadequate can require more information, and the material then has to be publicised again with a fresh period for representations of not less than 30 days. On a 16-week determination for EIA development, one request typically adds two to four months once you count the survey window you have missed.

When an authority can require further information

Regulation 25 gives the local planning authority, or the Secretary of State on a called-in application or appeal, the power to require further information where the Environmental Statement does not contain the information reasonably required to assess the likely significant effects of the development. The test is adequacy, not disagreement. An officer who dislikes your conclusion cannot use regulation 25 to force a different one, but an officer who cannot follow your method, or who finds a receptor unassessed, can and will.

Statutory consultees drive most requests. Natural England on a habitats matter, the Environment Agency on water quality or flood mechanisms, National Highways on the strategic road network, the county ecologist on survey coverage. Each of them writes a holding objection that lists what is missing, and the case officer converts the list into the request.

The regulations also require the Environmental Statement to be prepared by competent experts, and the authority to have access to sufficient expertise to examine it. That is why a chapter written without the relevant specialist input attracts a request almost automatically. An AI-assisted draft chapter can structure the argument and flag the gaps, and the assessment itself has to come from the competent expert who signs it.

What a request typically asks for

Requests cluster around a short list of recurring gaps:

• Baseline survey coverage: a season missed, a survey done outside the accepted window, or a study area drawn too tightly.
• Method transparency: model inputs, assumptions and sensitivity tests not given, so the result cannot be reproduced.
• Cumulative assessment: committed development omitted, or the list of schemes not agreed with the authority.
• Mitigation certainty: measures described without the mechanism that secures them, whether condition, obligation or management plan.
• In-combination effects on a European site, where a Habitats Regulations Assessment needs information the Environmental Statement did not supply.
• Residual effects: the significance conclusion stated without showing the step from magnitude and sensitivity to the judgement.

None of those are exotic. All of them are cheaper to fix before submission than after, because after submission the fix carries re-publicity with it.

An addendum or reissued chapters

You have two formats, and the choice affects cost more than people expect.

An addendum is a standalone document that answers the request and cross-refers to the original chapters. It is quick, it costs little in drafting terms, and it leaves the reader stitching two documents together. Where the request is narrow, an addendum is right.

Reissued chapters replace the originals in full, with change bars or a schedule of amendments. Drafting costs more, the figures and appendices have to be reprinted, and the reviewer gets one clean document. Where the request goes to the assessment method rather than a detail, reissuing is the safer route, because a significance conclusion that has moved cannot sit in an addendum without confusing everyone who reads the pair.

The third option, a consolidated Environmental Statement, is sometimes requested on large schemes after two rounds of further information. Budget it as a full re-production: typesetting, figures, non-technical summary, printing and the digital copies for deposit.

Re-publicity and the extra consultation period

This is the part that bites. Further information supplied under regulation 25 has to be publicised in the same way as the original statement: a notice in a local newspaper, a site notice, copies made available, and a period for representations of not less than 30 days. The authority cannot determine the application until that period has run.

Direct costs are modest and real: newspaper notice fees, printing and binding of deposit copies, and the charge some authorities make for making documents available. The consultant's fee for preparing the notices is trivial next to the four weeks of held programme, and the risk that a fresh round of representations raises a new issue that generates a second request.

A good case officer will tell you informally what is coming before the formal request lands. Use that window. The gap between "the ecologist is unhappy" and a written regulation 25 request is often three weeks, and survey work started in that gap can save a season.

What one request does to a 16-week determination

EIA development carries a 16-week statutory determination period under the Development Management Procedure Order 2015, and an extension of time is almost always agreed once further information is in play. Build the timeline out honestly:

The season risk dominates everything else. A request for a further year of bat activity transects, a spring botanical survey, or traffic counts in a neutral month outside August and December can push determination past the next committee cycle and into the following year. That is where the money goes: prelet dates, funding conditions, option agreements with expiry dates, and the standing cost of a project team on a scheme that cannot start.

Where scoping would have prevented it

Most regulation 25 requests trace back to a scoping stage that was rushed or skipped. Formal scoping under the 2017 Regulations gives you a scoping opinion from the authority, informed by statutory consultees, that records what the assessment must cover. It is not binding on the authority in the sense of preventing a later request, and it is strong evidence that you assessed what you were told to assess.

Three things in scoping pay for themselves many times over:

1. A written agreement on the cumulative schemes list, with a cut-off date.
2. Method statements for the contentious chapters, signed off with the relevant consultee before survey work starts.
3. A survey programme mapped against the calendar, showing which windows you are relying on and what the fallback is if one is missed.

Where a chapter is likely to be contentious, an Environmental Impact Assessment draft structured to the scoping opinion makes the gaps visible early, while there is still time to commission the work. The Environmental Statement itself must be prepared by competent experts, so treat any draft as the framework they work into.

Building a contingency into the EIA budget

Assume one request. Not as a pessimistic scenario, as the base case.

A workable contingency has three parts. First, a money line of a defined percentage of the technical fees, agreed with each consultant as a scope for one round of response rather than an open-ended retainer. Second, a programme line of at least 12 weeks between submission and the date you need a decision. Third, a survey line that keeps one seasonal window in reserve, which in practice means submitting early enough that a missed spring is recoverable in the same year.

Application fees themselves are indexed annually on 1 April, so check the current fee schedule rather than last year's figure, and remember there is no further fee for supplying information under regulation 25. The same pattern shows up in contaminated land investigation programmes and in daylight and sunlight evidence, where the second round of work costs more than the first.

And if the authority fails to determine within the agreed period, the fee refund provisions are a separate question from the further information process, covered in the fee refund rules for non-determination.

See PlanScope pricing if you want a fixed cost for the drafting layer of an evidence base: one free report, £50 per report, or £150 per month for unlimited reports on the Professional tier.

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.