TerraConsult have recently assisted a client with a successful Environmental Permit Surrender Application for a pre-Landfill Directive ‘inert’ landfill that closed in 2003. The site was in a rural location and had been restored back to agricultural use for some time.
Monitoring of the site demonstrated that it was benign apart from high concentrations of methane being present within the in-waste boreholes. Monitoring also demonstrated that the gas flow from the boreholes although usually negligible was occasionally significant in the context of a surrender application. This meant that the site did not fit within one of the landfill gas completion criteria given in the Environment Agency Landfill Surrender Guidance (EPR 5.02). The application process also highlighted that the two gas monitoring points per hectare standard described in the Guidance and drawn from Waste Management Paper 27 - Landfill Gas was an absolute requirement for a successful surrender application.
A review of the site and the data led us to believe that a successful application could be made. Therefore two extra monitoring locations were designed and installed and an accelerated period of monitoring was completed as agreed with the Environment Agency. The data from the new wells continued to show that the site did not fit into a completion criteria scenario.
This non-compliance with the Guidance became obvious during the early part of the monitoring period and enabled TerraConsult to carry out extra targeted monitoring visits, including during the extreme low pressure from Storm Caroline and utilise continuous monitoring to better understand the behaviour of the ground gas system.
The monitoring data coupled with TerraConsult many years of experience in the interpretation of ground gas monitoring allowed several strands of evidence to be developed. These demonstrated to the Environment Agency that the waste within the site was in a satisfactory state and would not pose a risk to the environment. Consequently, the Permit was successfully surrendered.
Please contact Ben King or one of my colleagues at TerraConsult if you wish to discuss the possibility of surrendering a closed landfill site permit.