Sundon Reservoir, Bedfordshire

June 2021

Risk Management Limited were employed on behalf of Affinity Water to undertake a Phase II Site Investigation at an existing reservoir to inform the design and construction of a new water condition plant.

Intrusive fieldwork consisted of 6 No. drive-in-sampler boreholes up to 9m depth, 2 No. hand auger boreholes up to 2m depth, TRL Dynamic Cone Penetrometer (DCP) tests up to 1.20m depth, 2 No. Soil Resistivity tests using a Wenner 4-point array, 3 No. falling head permeability tests and dynamic headspace analysis for Volatile Organic Compounds (VOC’s) using a Photo-inonisation Detector (PID).

Laboratory testing was undertaken in line with the Consulting Engineers, Mott MacDonalds, specification and included Natural Moisture Content tests, Atterberg Limit tests, Particle Size Distribution tests, Resistivity, MCV, MCV-Moisture Content Relationship, Lab CBR tests, Organic Matter, Carbonate Content, pH and Sulphate tests and Soil and Groundwater Contamination tests.

Groundwater and gas monitoring was undertaken over 4 visits and included purging, micro-purging and sampling of groundwater using either dedicated bailers or a Peristaltic Pump and low flow cell.