Teesworks - Some Risks

Teesworks - Environmental - Conceptual Site Models

Teesworks - Site Plans

Teesworks - Ecological Impact Assessments

Teesworks - Risk Assessments

The Teesworks' planning documents contain a lot of material related to the environmental state of the Teesworks' site and the impact of the planned works. While the documentation is extensive, it is surprising that while the extreme level of contamination of the Teesworks' Site was regularly stated during the compulsory purchase process to acquire a large part of the site from SSI, little extreme remediation was necessary to enable the development.

Having examined most of the publically available planning and marine license documentation, there are many assumptions that have been made in deciding how to develop the Teesworks' site that undermine the risk assessments that have been used to determine a minimum level of safe remediation that is necessary. Fundamentally, this makes the redevelopment of the site unsafe both for the natural environment and for the long term occupation of the site.

Firstly, there are three errors that have been made in the assessment of the nature of the site contamination:

1/ The level of contamination has been set based purely on sampling with no accounting for what is likely to be worse level of contamination which would be expected based on the history of the site.

2/ A particular type of contamination (DNAPLs) which should have driven the approach to remediation has been downplayed, resulting in the measures necessary to cope with this type of contamination not being taken. DNAPLs are dense non-aqueous phase liquids, as they are dense they concentrate at the highest impermeable strata below ground, they are effectively reservoirs of contamination which require explicit careful remediation. The appropriate methods for remediation of DNAPLs were not considered during the planning application process, despite DNAPLs being detected.

3/ Compounding the previous errors, the risk assessments are based on the assumption that contamination measured on site was representative of the contamination of the site. However, this will only be the case if the contamination is not localised and if it is uniformly dispersed by/in the water table. This is in fact stated as an explicit limitation by Arcadis in their assessment of the site contamination measurements - contamination measurement limitations.

4/ 200 Tonnes Oil Spil, each of the 2 million tonnes being dumped at sea contains at least 100g of oil, so 200 tonnes of oil is being dumped into the sea off the Tees Estuary.

Secondly, a high level approach to assessment of risk was taken that eliminated potential hazards based on inappropriately applying conclusions from one type of risk to another, specifically that if human health had been deemed to be protected, then the health of the natural environment would be protected as well.

Arcadis acknowledge this "It should be noted that ground conditions between exploratory holes may vary from those identified during this ground investigation; any design should take this into consideration. It should also be noted that groundwater levels may be subject to diurnal, tidal, seasonal, climatic variations and those recorded in this report are solely dependent on the time the ground investigation was carried out and the weather before and during the investigation."

Basically the results could be different tomorrow, 50cm away etc..

Page 3(8) - Arcadis