Performance evaluation and pollution control

First, let us consider what is pollution prevention: One of the commitments of the environmental policy (5.2); prevention of pollution is what is done by an organization to reduce or control the creation, emission, and discharge of any waste or pollutant related to the environmental aspects. 
So, while determining environmental aspects and impacts (6.1.2), you should identify any creation, emission, and discharge of any waste or pollutant. Develop action plans (6.1.4) to prevent, reduce or control pollution. Those action plans will be translated into operation improvement (8.1) and emergency prevention and response (8.2). Performance evaluation (9.1) will check if results are according to what was planned.

You can find more information about ISO 14001 below:

• Glossary of Environmental Management Words - https://advisera.com/14001academy/blog/2019/08/27/key-iso-14001-benefits-to-customers/nowledgebase/glossary-of-environmental-management-words/
• How to measure the effectiveness of your EMS according to ISO 14001:2015 - https://advisera.com/14001academy/blog/2016/09/05/how-to-measure-the-effectiveness-of-your-ems-according-to-iso140012015/
• Enroll for free in this course – ISO 14001:2015 Foundations Course - https://advisera.com/training/iso-14001-internal-auditor-course/
• Book – The ISO 14001:2015 Companion - https://advisera.com/books/the-iso-14001-2015-companion/