Effectiveness of the EMS

First, what does effectiveness stand for? Effectiveness is about achieving planned results.
What are the main planned results for an environmental management system? Its environmental objectives.

So, does your organization have good environmental objectives? Are those environmental objectives in line with the environmental policy commitments (Continual improvement, Prevention of pollution, compliance with legal and other requirements)? Are those environmental objectives about the most significant environmental aspects and impacts of your organization? Fuel consumption? CO2 emissions? Used lubricant oils? Used tires and other wastes?
Are your environmental objectives being met?

The following material will provide you information about environmental management systems:

• How the transportation business can benefit from identifying environmental aspects according to ISO 14001 - https://advisera.com/14001academy/blog/2016/05/09/how-the-transportation-business-can-benefit-from-identifying-environmental-aspects-according-to-iso-14001/
• 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/