KEY MESSAGES
The former WWTP is part of our National Industrial past and part of the history of South Cambridgeshire.
The land at the former WWTP needs to be cleaned up (remediated) as the soil and groundwater are currently contaminated with chemicals from the site’s past use. This needs to be done, whatever the future of the Site may be.
As the land is already contaminated, doing nothing is not an option. The soil and groundwater need to be cleaned.
The land is destined for commercial end use and as, such, must be cleaned to a high standard. This takes into account the most sensitive of people who might come into contact with it.
The clean-up is likely to take 18 months.
The clean-up is being closely monitored by SCDC and the Environment Agency with advice from the UK Health Security Agency to make sure it is being undertaken properly and that the works do not pose an unacceptable risk to human health or the environment.
The works at this WWTP Site are very different to the works undertaken in 2010/2011 on the main production Site. At this Site, not only are the works significantly smaller than previous works, but we are also able to remove a significant proportion of the odorous contamination in situ before any excavation works.
The works have been planned so that the most contaminated material is identified and treated first.
The remediation is taking place both in-situ and ex-situ, meaning:
In Situ: Soil Vapour Extraction (SVE) will remove potential odorous materials before the ground is excavated.
In Situ: A plume of contaminated groundwater will be treated in situ via the injection of remediation products.
Ex-Situ: Soils will be excavated and treated at the surface, but the volume of this is a fraction of that treated in 2010.
Ex-Situ: Contaminated groundwater will be pumped from excavations and treated by a water treatment system.
Wind conditions are monitored, and the weather forecast is used to schedule works, the purpose of which is to minimise odours in the direction of Hauxton and Harston villages.
The works are continually monitored on Site. Air quality around the Site is checked several times per day (and more frequently if required). Air monitoring tubes are collected on a 28-day cycle and sent to an accredited laboratory for analysis.
Some local residents in the first phase of the remediation of the production Site (2010/2011), reportedly experienced headaches or nausea as a reaction to the odour. However, the forerunner to the UK Health Security Agency (the Health Protection Agency) and NHS Cambridgeshire advised that the levels of compounds identified, either from the remediation works or the deodorising system used on Site, were very unlikely to pose a health risk.
If a particularly odorous volume of soil is discovered and the wind is carrying it towards the village, works on that part will cease and the soil will be covered until the conditions change and work can continue.
It is not possible to eliminate all odours from the treatment process, but they are mitigated as far as practicable.
All treatment processes being used on Site are well-established techniques for treating a variety of different organic contaminants and are in use across many contaminated sites in the UK.
If the soil cannot be successfully treated, it will not be introduced back to the Site, but it will be taken away.
Once the works are complete, the Site will no longer pose a significant risk to the surrounding area and, following an agreed monitoring period, will be suitable for redevelopment.
We are wanting to work with the local community to remove the contaminants from their environment.
