Someone’s had a word with Amec. Certain sentences have mysteriously disappeared from the new water report to support Aggregate Industries' revised planning application to quarry Straitgate Farm. Amec's previous report had talked about uncertainty and steps in the water table related to faulting:
But that's gone in the new report:
The old report talked about incomplete parameterisation of the detailed groundwater dynamics of the Site.
But that's been removed too:
Amec's last report said there was likely to be other unmapped local faulting.
The new report now says may.
Clearly someone has taken a red pen to the old report and removed anything which indicates uncertainty over where the maximum groundwater level lies.
Two piezometers have now been installed in the middle of the site, but have produced less than 12 months of data, and certainly no new maximums. Possibility for steps in the water table related to unmapped local faulting will not have gone away.
It remains the case that the maximum groundwater contours across an extraction zone of more than 60 acres have been modelled from just six high water points. Last year, we asked DCC:
Since AI now intends to dig right down to the maximum water table, perhaps you could ask Amec to confirm the specific level of accuracy (in +/- m) to which their maximum groundwater contours are mapped?
DCC asked Aggregate Industries and Amec for an answer. Amec now says:
Monitoring over the exceptionally wet winters of 2013 and 2014 allow this surface to be defined with confidence. 6.2.2
But Amec still hasn't got the confidence to provide the level of accuracy (in +/- m) this surface is mapped to. It is this level that AI would quarry down to. Amec assures us that:
Groundwater levels would be lower than this elevation for the vast majority of the time 4.2.17
Which won't sound like a maximum groundwater level to most people. Furthermore, it's very unlikely that during four years of monitoring, Amec will have captured the highest groundwater levels. It is for this reason and others that it is standard to leave at least 1m unquarried above the maximum recorded level. The EA has so far agreed. This was their last response to the Minerals Plan:
Amec says, and this is priceless:
4.1.3 In discussion with the EA they indicated that they would like to see the maintenance of a 1m unsaturated “freeboard” above the highest recorded groundwater level. AI have confirmed their willingness [NOT] to meet this requirement by adopting the following approach to the proposed method of working:
by saying:
Budleigh Salterton Pebble Beds (BSPB) will be excavated down to the elevation determined from the highest recorded winter water level.
So that:
in all circumstances except the few weeks that it will take to strip the BSPB and replace the overburden – there will be at least 1 metre of overburden above the High Winter Water Table. 5.3.6
In other words, confirming AI's willingness to NOT leave the 1m freeboard that the EA requires.
How would AI's scheme work?
Continuous groundwater level monitoring throughout the life of the quarry will ensure that this level is confirmed. 6.2
But look at the latest groundwater results - the ones that have not informed AI's application. Piezometer PZ05 failed in October 2016 and is still not active.
Amec assures local residents reliant on the site for their drinking water that:
No working down to the winter water level will be undertaken during the winter months (unless required in an emergency situation)
What an emergency situation might be, Amec does not say. To AI, running low of gravel stocks could be an emergency.
For anyone wondering what assurances there would be for restoring water supplies if problems were to occur. In 2015, the EA had said:
We therefore recommend that a Section 106 agreement is put in place prior to the commencement of the works. This would require the ‘making good’ of any derogation to an agreed list of water supplies by the provision of alternative supplies
DCC requested that AI produce a "Heads of terms of a s.106 agreement to replace private water supplies affected by workings":
This should include very clear proposals for responses to allegations of derogation of water supply, including timescales and methodology for action.
A draft Heads of Terms was provided "for discussion with DCC", set out in Item 11 here. Many local people were not happy with "If we dispute that the derogation is caused by our working we may..." etc etc.
But in this application? Nothing. There's no draft Section 106, and nothing about making good. Surely if AI's so confident that its unorthodox seasonal working scheme would not impact private water supplies, it could offer a Section 106 with all the bells and whistles? After all, what's it got to be worried about?
