Dungeness in Danger
by Dennis LeggettSo why worry?
The Marsh overall has been defended. Sea levels have steadily risen (Appendix C ), but Government policies have coped with the effects. Modern technology and engineering gave the confidence, during the Second World War, to flood Pett Levels and other parts as defence measures. We now can monitor beach gravel movements to assess the changes produced by longshore drift and wave energy. (See Appendix A) Thus instead of building sea walls we can use grabs, lorries and bulldozers to relocate gravel that has been shifted along the beaches. The capacity to drain marshes and regulate river flows increases. The sea defences have remained intact, despite gravel losses and at the cost of river flooding which can overwhelm drainage control.
So why worry about Dungeness Power Stations?
The reasons are various and are not derived from the debates on the value of nuclear power. Concerns lie with the unstable condition of the site. The argument is:
• The present defence systems of the Area demand increasing capacity as the land sinks and storms increase. They can never be classed as totally safe. If they are overwhelmed by storms essential services to the Power Stations, such as the removal of extremely dangerous radio active waste, the supply of carbon fuel for maintenance vehicles and generators, as well as gravel for sea defences, will be threatened.
• In particular the migration of the Ness threatens the Power Station. Its gravel ridges started accreting to the south of its present position, about 2000 years ago. It appears to have migrated north and east as it grew. At present the coast fronting the Power Stations would erode at an estimated rate of 6 metres a year if unprotected. An average of 100,000 cubic metres gravel are relocated each year to maintain the sea defences bounding Pett Levels, Walland Marsh and Romney Marsh . Of these 30, 000 cubic metres go to the defence of the Power Station. Future demands will be greater.
• Present estimates of future needs are based upon a small database of past events. It is not closely related to future increases the magnitude of which are presently unforecastable.
• Before gravel is relocated along a beach some is lost. Replacement sources are increasingly difficult to find.
• Nuclear reactors pose a biological threat to human life for at least a century after decommissioning, accepting minimal estimates, and given adequate entombment of the reactor cores.
• Within this time frame large areas of Greater Romney Marsh are unstable.
Approximately half the Marsh was lost to the sea within 60 years during the last major perturbation.
The probability of disaster becoming reality is not remote. Greater storm frequency and violence are forecast by reputable agencies such as Munich Re, (See Appendix C), and the UN Intergovernmental Panel for Climate Change. Tidal waves have been and can be generated by rock or ice subsidence. For example the Florida coast is threatened by part of an Azores island the size of the Isle of Wight, subsiding into the sea. On the night of October 16th 1987 a 'hurricane' struck the East Sussex coast, the full fury of its seas not quite reaching the Power Stations. The tide that night was low. (Appendix B) Mentioned earlier is a report of the sea reaching the Power Stations as a result of storms. In the event of storm driven surges combining with Spring Tides that cannot be contained, we could witness a marine induced Chernobyl.
Surely we should be planning for the decommissioning of the nuclear power stations in the near future? The technical requirements need to be itemised, dare I say, made concrete. The timetable for the initial and long term stages should be confirmed and initiated soon. Most important of all, confrontation should be avoided by looking to the futures of the work-force, most of whom could be retained during the lengthy process of decommissioning..
To produce and execute the plan an independent, multidisciplinary taskforce is required to quickly evaluate the present state of knowledge of the Area, ascertain the exact specifications for decommissioning and set a starting date.
next: Appendix A (Waves and Surges)