Chromium-6 is the cancer causing chemical, made famous by the Erin Brockovich court case and film. ‘Unexpectedly’ high levels of Chromium-6 have been found at HS2 work sites across the Colne Valley, thought to derive from vast cement works. Levels of 77 ug/l (parts per billion) have been recorded in run off at the HS2 Western Valley Slopes site and concentrations of 45 ug/l (ppb) have been found in water in the cofferdams in the Colne Valley lakes above the aquifer!
HS2 Ltd do not know why such high levels of chromium-6 are being generated but they know it happened in the cofferdams when the concrete plugs were setting. Most forms of chromium are harmless but chro-mium molecules can be converted into harmful chromium-6 by industrial processes and chemical reac-tions. The Colne Valley sands and gravels contain high levels of manganese which can react with chro-mium in cement and convert chromium molecules into toxic chromium-6. Different forms of chromium can convert back and forth in water and in the human body, depending on environmental conditions.
After the Brockovich case, the state of California set a public health goal of 0.02 ppb for drinking water. UK Government guidelines state that a level of 5 ug/l (ppb) of chromium-6 is the concentrations in groundwater below which the danger of deterioration in the quality of the receiving groundwater is avoided. In the Colne Valley however HS2 are working directly in four inner source protection zones where naturally filtered groundwater is intended for human consumption.
Throughout 2022 HS2 Ltd has been pile driving holes up to 80m deep into the chalk aquifer under the Colne Valley floor for the supports of the Colne Valley Viaduct. There are now nearly 300 holes filled with bentonite fluid, waiting to be filled with concrete. The gigantic concrete pour for the viaduct foundations is due to start at the end of January 2023 when all the pile driving is finished. This is a public health disas-ter waiting to happen.
What can be done ?
1. HS2 must find out and tell us, why high levels of chriomium-6 are being generated at their works.
2. HS2 must make a plan to prevent chromium-6 being made during concrete use.
3. Frequent, routine monitoring for chromium-6 needs to be undertaken at each viaduct pier and HS2 outfall.
4. The data should be available to the water company, local authority and the public for independ-ent scrutiny.
5. Tap water taken from the impacted sources needs regular testing for chromium-6. There should be no cover up.
What you can do.
Please send an urgent email (use write to them) to your MP asking the following:
Dear Sir / Madam
There are clear warning signs that HS2 cement works in the Colne Valley are producing higher levels of chromium-6 than anticipated or desired. In January 2023 HS2 plan to pour vast amounts of cement into 300 very deep holes in the chalk aquifer for the concrete support pillars of the Colne Valley Viaduct. This presents an unassessed danger to public water resources and tap water supplies in West London and sur-rounding areas.
Therefore as a matter of urgency, please ask HS2 Ltd to:
Explain the high levels of chromium-6 at their Colne Valley sites, what environmental factors are driving these levels and what can be done to mitigate the situation? How can chromium-6 be prevented from being generated and prevented entering the aquifer from the concrete foundations of the viaduct. What monitoring can be put in place, if any, and who can oversee this?
The risk assessment for the Colne Valley Viaduct did not consider chromium-6, this needs to be rectified. None of us want to drink water containing chromium-6, the cancer causing chemical made famous by Erin Brockovich.
This picture shows Arthur Pendragon blessing the aquifer and drinking water against increasing impacts of HS2
