Understanding groundwater protection

What to include in your mitigation, Verification Plan and Verification Report for groundwater monitoring required for planning applications and discharge of conditions

To avoid unacceptable risks to groundwater in accordance with NPPF policy 174(e) a verification plan that includes proposals for groundwater-monitoring should be prepared by a ‘’Competent Person’ and included in the planning application. This should ideally include:

• Detailed proposals for a groundwater-monitoring programme to encompass regular monitoring for a period before, during and after ground works.
• A schedule for decommissioning boreholes prior to construction works,
• A borehole location plan (with scale & North arrow) for cross-referencing,
• An intended programme/ frequency of monitoring,
• A schedule of in-situ field and laboratory chemical parameters,
• Details of how the installed monitoring wells will be protected and how they will be replaced if they are damaged, and
• A contingency action plan including the list of potential mitigation measures that will be implemented, should unexpected changes in groundwater quality be noted as a result of decommissioning or redevelopment works. 

Please note that the groundwater monitoring wells will need to remain in place until the regulators have confirmed that monitoring is no longer required.

The Environment Agency does not provide ‘good practice’ guidance but further guidance on groundwater monitoring can be found in the following:

• BS ISO 5667-22:2010 Water quality¹. Sampling. Guidance on the design and installation of groundwater monitoring points
• BS ISO 5667-11:2009, BS 6068- 6.11²: 2009 Water quality³. Sampling. Guidance on sampling of groundwaters (A minimum of 3 groundwater monitoring boreholes are required to establish the groundwater levels, flow patterns but more may be required to establish the conceptual site model and groundwater quality. See RTM 2006⁴ and MNA⁵ guidance for further details)
• BS ISO 18512:2007 Soil Quality⁶. Guidance on long-term and short-term storage of soil samples
• BS EN ISO 5667:3- 2018⁷. Water quality. Sampling. Preservation and handling of water samples
• Guidance on the design and installation of groundwater quality monitoring points Environment Agency 2006 Science Report SC020093⁸ NB. The screen should be located such that at least part of the screen remains within the saturated zone during the period of monitoring, given the likely annual fluctuation in the water table. In layered aquifer systems, the response zone should be of an appropriate length to prevent connection between different aquifer layers within the system.
• The verification report should be undertaken in accordance with the following guidance: Verification of Remediation of Land Contamination⁹

Decommissioning boreholes

To ensure that redundant boreholes are safe and secure, and do not cause groundwater pollution or loss of water supplies in line with paragraph 174 of the National Planning Policy Framework and The Environment Agency’s Approach to Groundwater Protection¹⁰: the  Verification report for the decommissioned boreholes should include records of:

• the reason for abandonment
• groundwater level prior to decommissioning
• any removal of casing or attempts to remove the casing
• the depth, position and nature of backfill materials
• problems encountered during decommissioning.

Further detailed decommissioning borehole advice can be found in these links:

• Using Science to create a better place¹¹
• Decommissioning redundant boreholes and wells¹²
• Good practice for decommissioning redundant boreholes and wells¹³

1. https://knowledge.bsigroup.com/products/water-quality-sampling-guidance-on-the-design-and-installation-of-groundwater-monitoring-points/standard
2. https://standardsdevelopment.bsigroup.com/projects/2006-01734
3. https://standardsdevelopment.bsigroup.com/projects/2006-01734
4. https://www.gov.uk/government/publications/remedial-targets-worksheet-v22a-user-manual
5. http://www.ukhydrogeologist.co.uk/documents/guidance-on-the-assessment-and-monitoring-of-natual-attentuation-of-contaminants-of-groundwater.pdf
6. https://knowledge.bsigroup.com/products/soil-quality-guidance-on-long-and-short-term-storage-of-soil-samples/standard
7. https://knowledge.bsigroup.com/products/water-quality-sampling-preservation-and-handling-of-water-samples/tracked-changes/preview
8. https://www.gov.uk/government/publications/guidance-on-the-design-and-installation-of-groundwater-quality-monitoring-points
9. https://www.gov.uk/government/publications/land-contamination-risk-management-lcrm/lcrm-stage-3-remediation-and-verification
10. https://www.gov.uk/government/publications/groundwater-protection-position-statements
11. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/290727/scho0106bkct-e-e.pdf
12. https://online-befirst.lbbd.gov.uk/planning/?fa=downloadDocument&id=215514&public_record_id=26717
13. https://webarchive.nationalarchives.gov.uk/20140328154120/http:/cdn.environment-agency.gov.uk/LIT_6478_8cbe6f.pdf