Compliance assessment scheme

As Scotland's environmental regulator, we issue a range of licences designed to control activities that could lead to pollution or environmental damage. Compliance with these licences is important in ensuring that the environment and human health are protected.

We believe that the industries and businesses we regulate should find it as easy as possible to understand their responsibilities; enabling them to comply with the regulations and realise the many economic benefits of good environmental practice.

Our compliance assessment scheme (CAS) has been designed to demonstrate the level of compliance associated with specific licence conditions.

The compliance assessment scheme now applies to our four principal regulatory regimes namely:

Regulatory regimes in CAS
  • Pollution Prevention and Control Regulations (PPC) - Part A and Part B
  • Waste management licensing (WML)
  • Controlled Activity Regulations (CAR) - Point source and water resources
  • Radioactive Substances Act (RSA)


These regulatory regimes cover industrial processes; waste treatment and disposal; emissions to air; discharges to water, abstraction and impoundment of water and radioactive substances.

The scheme was first introduced in 2009 for sites covered by the Pollution Prevention and Control Regulations and has been phased in to cover approximately 10,000 licences. We use a risk based system to identify which sites get a site based inspection in any given year. The highest risk sites and poorly performing sites will receive multiple site based inspections per year and the lowest risk sites will receive a site based inspection every five years. The results of our sampling, site data returns and desk based inspections are also used to calculate the annual compliance result. Should a site have an environmental incident this is also fed into the scheme along with any subsequent follow-up inspections.

Because of the risk based system the number of sites reported within the scheme fluctuates year-on-year.

In addition to the annual published result, we will publish inspection reports for those regulated under Part A of the Pollution Prevention and Control (Scotland) Regulations 2012 (PPC 2012). The report will be displayed for those sites with an inspection carried out from 1 January 2014. Reports will be updated on the results page periodically. The result of the inspection will contribute towards the overall Compliance Assessment Scheme score for that year (e.g. 12/06/2014 will count towards the 2014 assessment score). Should you require further information on how we assesses compliance, please refer to Compliance Assessment Scheme.

We have carried out minor reviews and modified the scheme since its inception in 2009 with any changes documented in the CAS manual of that year. We are currently undertaking a significant review of the Scheme; we held a public consultation from 14 August to 10 November 2017; accompanied by a series of stakeholder workshops to discuss proposals and gain feedback. The consultation closed on 10 November and the consultation responses have been reviewed. The feedback we have had from stakeholders highlighted a number of key areas which require further consideration. Against this backdrop, SEPA will undertake further work to refine our proposals.

We always knew we were being highly ambitious in trying and design changes that could be put in place on the 1st of January. We strived to meet this ambition, but it's clear we need some more time to make sure any changes improve the accuracy and usefulness of CAS for the public, regulated businesses and ourselves.

SEPA’s current Compliance Assessment Scheme, in operation since 2009, will remain in force whilst further work is undertaken.