Hydrogeology Meeting

A virtual meeting took place yesterday, called by Professor Brassington, chaired by Devon County Council (1), with personnel from the Environment Agency (4), Aggregate Industries (1), Consultants Wood (2), and various other stakeholders (5), to discuss the hydrogeology at Straitgate Farm. Prof Brassington proposed the subject of the meeting to be: 

My view of the conceptual model of the system at Straitgate Farm differs from that put forward by Wood — in particular the rate of vertical flow of recharging waters through the unsaturated zone and the impact of reducing the unsaturated zone on spring water pH.  I would like to discuss the technical evidence behind the assumptions made by Wood and those that I have used. 

Prof Brassington prepared two notes for circulation before the meeting: Infiltration rates and unsaturated hydraulic conductivity and Recharge velocities through the unsaturated zone.

The Environment Agency's response to the recent consultation has now been deferred, pending:

1. Wood (on behalf of AI) to provide written response to Professor Brassingston’s circulated meeting notes for the EA and DCC to review. 

2. Wood (on behalf of AI) to provide the MPA with a drawn together note on the existing data on water chemistry and pH.

Goodness, it’s revolving doors at AI as yet another CEO takes the helm

Dragan Maksimovic has today been announced as the new CEO of Aggregate Industries.

He replaces Guy Edwards, "who has decided to pursue other career opportunities." It was just a few months ago that Mr Edwards – who only took on the CEO position in December 2018 – commented on the Straitgate application.

Mr Maksimovic is apparently: 

…delighted to join Aggregate Industries, one of the leaders in the construction industry. The UK is one of the most important markets for LafargeHolcim and I am very excited to be offered the opportunity of leading the organisation on its successful path. I am committed to making AIUK the leading company in the UK for sustainable and innovative building solutions, and with my strong and passionate team by my side, I look forward to the challenge.

Mr Maksimovic will be Aggregate Industries’ fifth CEO during the time that the company has been struggling to gain permission to quarry Straitgate Farm. This is clearly an indication of just how long the Straitgate Farm fiasco has been staggering on, but could it also be an indication of deeper problems?

AI’s conceptual groundwater model is based on a BIG mistake

Aggregate Industries and consultants Wood, previously Amec Foster Wheeler, tell us that Straitgate: 

...is underlain by Budleigh Salterton Pebble Beds (BSPB) deposits which form part of the Sherwood Sandstone Principal Aquifer. 

On that we can all agree. It’s the rest that’s a problem. The above consultants have previously argued: 

...recharge reaches the water table in the BSPB through unsaturated thicknesses of between approximately 3 and 10 m within between 1 and 3 days. This is consistent with the conceptual model for relatively rapid recharge occurring in the BSPB (i.e. days rather than weeks or months). 

The problem? It's not days. It’s years. The British Geological Survey Permeability Index says: 

Even in the Sherwood Sandstone... recharge can take several years to reach the water table

Professor Brassington says the same: 

According to Wang et al (2012) the unsaturated zone velocity for the Sherwood Sandstone Group falls in the range 0.6 – 2.3 m/year with a mean of 1.06 m/year (these values were summarized by Chilton and Foster (1991)). The values for unsaturated zone flow rates are several orders of magnitude (three to five) lower than flow velocities in the saturated zone. 

Scientific papers echo this – that for Sherwood Sandstone the flow rate of water percolating through the unsaturated layer is measured in metres per year (m/a), not metres per day:

Isn't this embarrassing? This is something hydrogeologists are supposed to learn about at university as undergraduates, that the water flow in the unsaturated layer above the water table can be many times slower than in the saturated layer below the water table, that percolating water moves more easily through the underlying strata when all of the pores are filled with water (saturated) than when some of the pores are filled with air (unsaturated). In other words, according to BGS again: 

vertical flow under unsaturated conditions will be slower than under similar saturated conditions (often considerably so) 

The ‘unsaturated hydraulic conductivity’ is not a constant but rather a function of the volumetric water content. Hence at low volumetric water contents (e.g. late summer and early autumn) the hydraulic characteristics and behaviour of contrasting lithologies in the unsaturated zone may be quite different to their behaviour in the saturated zone. 

Click on the drawing below for a lesson in water flow in unsaturated soils from the University of California, Davis, or this course from a university in Syria.

 

What difference does all this make? It means that Aggregate Industries' conceptual model of how the groundwater behaves at Straitgate Farm is fundamentally flawed. Removing the unsaturated layer – which is what the company wants to do – would in time permanently change the chemistry of the groundwater, making it forever more acidic for those that have long been dependent on it – be they people, a Grade I listed house with mediaeval fishponds, livestock farms, or wetland habitats in ancient woodland. In relation to the Cadhay spring for example, Prof Brassington says: 

The water takes almost 15 years to make this journey and if all but 1 m of the unsaturated zone is removed this reduces some 50% of the total travel time. 

This reduced period will mean less time for rock/water interaction and will result in a less chemically mature groundwater that is more acidic.

The impact on the travel time also means that the deterioration of the groundwater chemistry will be a permanent change and it will not be possible to reverse it. 

The concern for the 100 people or so who obtain their water supply from these springs is that the water make up will substantially change and a reduction in the pH will mean that the water is too acidic for drinking without treatment and it will dissolve metal pipework and storage tanks. 

So, why have Aggregate Industries’ consultants got something so fundamental so very wrong? Did they make a simple blunder one day and found it difficult to backtrack and say sorry? Was it to stack the argument in favour of their paymaster? Or was it because they need to go back to the classroom?

 

LLFA objects again to Straitgate proposal

Devon County Council's Flood Risk Management Team – in its role as Lead Local Flood Authority – has objected to the proposal by Aggregate Industries to quarry Straitgate Farm:

   

 It is now the second time the LLFA has objected to the application:
 

Without further information, ‘Natural England may need to object to the proposal’

Since submitting its first planning application to quarry Straitgate Farm back in 2015, Aggregate Industries has been granted 6 years by Devon County Council to resolve the various problems that have arisen.

 

And yet, there are still a multitude of substantive issues the company must resolve. Would it ever be able to resolve them? Are the complexities of Straitgate Farm simply beyond the capabilities of Aggregate Industries and its paid-up army of consultants? 

What hope is there to resolve the complicated issues, when it can’t even get the basics right? Take soils. 

Straitgate Farm comprises best and most versatile agricultural land. The Devon Minerals Plan says: 

The site should be restored to enable resumption of agricultural use. To ensure the site is restored to an appropriate grade of agricultural land quality, proposals should assess the Agricultural Land Classification and detail proposed soil management techniques should be used throughout the site working and restoration stages. The working and restoration phasing should minimise the area of land not in cultivation, as soil is best conserved by being farmed rather than stored where some deterioration may occur. 

Restoration back to BMV would obviously be a tall order, given that topsoils would be stored 3m deep for up to 12 years. The company's supporting statement claims "The long term after-use would be light intensity agricultural grazing." Land that could only support "light intensity agricultural grazing" is by definition not BMV. Soils suffer significant deterioration when stockpiled in piles more than 1m deep for long periods of time. They suffer rapid loss in organic carbon levels and soil organisms. Earthworms are key for soil quality but do not survive at depths greater than 1m. Soils stored in bunds become anaerobic within a few weeks. Soils stored for longer than a year suffer irreversible impacts. 

Natural England has now responded again to the application. It is the fifth time this statutory agency – the one charged with protecting our natural environment and the one now "cut to the bone" – has had to deal with the proposal – excluding the multitude of responses in relation to the site's inclusion in the Minerals Plan, and Aggregate Industries' in-tandem applications to import material to Blackhill and Hillhead. Previous Natural England responses for Straitgate can be found here, here, here and here. 

Natural England first warned Aggregate Industries about soils back in 2015: 

as the site is BMV, the same area of BMV land should be restored. If there is no topsoil in an area it cannot be returned to grade 3a. 

Details are needed on the restored profile. Para 3.42 refers to a restored profile of 1m, whereas the usual target profile would be 1.2m. The MAFF ALC survey shows that there are two distinct subsoils, which should be stripped and stored separately ready for replacement, however there is only reference to a single subsoil in the supporting documents.

In 2017, Devon County Council tried to help the company: 

Given the nature and extent of the comments and requirements from Natural England regarding soil storage it would be helpful if you could update the soils management strategy to include the comments made by NE. Additionally, I would wish AI to comment on the relationship between the NE requested condition that soils should not be stripped in the winter months, the ongoing farm management and soils storage methodology. 

A soils management report was duly produced – the one recently consulted on – claiming "no loss of best and most versatile land." It was a big claim, and a questionable one, particularly given all the material needed to buttress the A30. 

But nothing was written about soil movements during the winter, or – remembering the Mineral Plan's advice that "soil is best conserved by being farmed rather than stored" – how soil storage would work with ongoing farm management. Nothing was written about separately storing the "two distinct subsoils" that Natural England had referenced in 2015. 

So here we are, in 2021, with Aggregate Industries still not having worked out something as basic as how and where it will store all the soils. Is the company just incompetent? Natural England now says: 

As submitted, the application could have potential significant effects on soils. Natural England requires further information in order to determine the significance of these impacts and the scope for mitigation. The following information is required: • The degree to which the best and most versatile land should be capable of being reclaimed without loss of quality. Without this information, Natural England may need to object to the proposal. 

The Soil Management Scheme and the detailed area plans submitted do not clearly identify the origin, intermediate and final locations of soils for use in the restoration, as defined by soil units (topsoil T1 and subsoils S1 and S2), together with details balancing the quantities (demonstrating the site has storage capacity), depths, and areas involved. We would expect restored soil profile to resemble pre working soil profile … if the grade is to be maintained. 

...the Soils and Agricultural Land Classification Report (ES Ch 14) states that there is Grade 2, 3a and 3b soils present on site…. reports should detail how it is intended to restore an equivalent area of Grade 2 and 3a of the soils on site being disturbed by these proposed works, specifically with soil volumes and restoration profiles provided. 

Without the separate stripping and storage of the subsoil S1 and S2, the accurate detailing of their storage location, and the restoration as described in the ES Ch 14 above it is our advice that this would [compromise] the ability to achieve high standards of restoration and to restore the land to agricultural best and most versatile quality. 

Aggregate Industries has had so much time – more than enough time, most reasonable people would think – to sort these things out. What is the point of statutory consultees providing response after response if Aggregate Industries just ignores them?

The Great MWWT Hoax – AI’s groundwater model has been sketched by hand

We have long argued – as have others, including Professor Brassington and Dr Rutter – that Aggregate Industries' model of the maximum groundwater levels – the MWWT, the base of any quarry, denoted by the contours below, originally guesstimated across 55 sloping acres from 'maximum' water levels recorded in just 6 boreholes – is not accurate. How on earth could it be?

Meanwhile, in the land of fairy tales, Aggregate Industries’ consultants – Amec Foster Wheeler now Wood – have over many years been peddling the story that the MWWT – the determinant of the recoverable resource and hence the proposal’s monetary worth – was generated by a clever and super accurate computer algorithm, NOT by the hand of some easily persuadable human. 

Lots of people were taken in by this story, including the Environment Agency. 

Documents were produced on the subject, following a meeting we had with the Environment Agency in September 2017, when Aggregate Industries was asked to supply:

A description of the tolerance levels and interpolation method used to produce the ‘Maximum Winter Water Table’ grid 

At this point, consultants had every chance to come back and say we used a sharp pencil and our immense brain power. But they didn’t. Consultants said: 

Four alternative grid interpolation methods were selected: Simple linear Kriging; A Radial Basis Function; Inverse Distance to a Power; Triangulation with linear interpolation. Each of these methods represents an exact interpolator in which the input data point will be preserved and respected by the interpolation algorithm…. The grid determined by Radial Basis Function was therefore adopted as being a more conservative preferred method for estimating the maximum water table distribution. 

Clearly, consultants accepted they were estimating, but no indication of the accuracy of this estimation was supplied, so in February 2018, the Environment Agency asked again. The consultants came back with more nonsense: 

The description of how the MWWT grid was calculated explained that two of the interpolation methods used produced realistic results (in line with expected hydrogeological behaviour and professional judgement). One method, ‘Radial Basis’ produced a grid that was generally higher than the other grid prepared by a Kriging method. As the MWWT was subsequently based on the higher of the two interpolated surfaces (i.e. Radial Basis interpolation) this could be considered to represent the upper limit of interpretation, with the Kriging interpolation representing the lower limit of interpretation and therefore the difference between these two realistic grids could be considered as reflection of the ‘tolerance’. 

It was a bogus argument. The Environment Agency asked more questions, and were told:

The generally higher Radial basis grid is subtracted from the generally lower Kriging basis grid to give an indication of “tolerance”….The Radial grid formed the basis for the final composite MWWT (shown in Figure 5), which also underwent final adjustment (upwards) to take further account of hydrogeological professional judgement. 

More gibberish, but the Environment Agency was satisfied. In June 2018 it wrote: 

We have reviewed the document and we are satisfied that it answers our questions about the derivation of the Maximum Winter Water Table grid.

But all the radial basis and kriging talk was baloney. A mathematician has analysed the MWWT, and has concluded "it is not a radial basis function, per se": 

If a sensible, well conditioned parameter and an appropriate generating function are chosen, a radial basis function will be a well behaved mathematical surface with continuous, smoothly differentiable contours between interpolation points... The only conclusion is that AI have defined their MWWT by hand.

And indeed, if we look through the myriad of documents, we find a map showing "hand contoured groundwater levels for February 2014 (mAOD)" submitted with the 2015 application, and again thereafter:

If we overlay these hand drawn contours over the MWWT (before recent changes) we find miraculous agreement over large areas. Check out the agreement along the 141mAOD contour, the 145m contour, the 148m contour, the 150m contour; the hand drawn contours are grey, the MWWT contours are blue. 

No mathematical model, no matter how clever, radial basis, kriging or otherwise, could produce such agreement from just – as it was originally – 6 numbers. A similar overlay with the MWWT recently supplied (and recently adjusted for elevated groundwater levels along the eastern boundary) shows corresponding agreement – see below – to areas not recently tweaked. 

This means that consultants have not only been spinning a long and convoluted yarn to the Environment Agency, but have used whatever professional judgement they have – which may of course be biased, compromised, subject to errors or simply lacking – to guesstimate the levels that their fee-paying client may dig down to; in other words, deciding exactly how much money Aggregate Industries could lay its hands on. Anybody smell a massive conflict of interest? 

And knowing that the MWWT has been drawn by hand, on the back of a proverbial fag packet for all we know, means there is certainly NO basis for claiming cm accuracy of these contours, and EVERY basis for not trusting them, and EVERY need to add a very large safety margin above them to accommodate "professional judgement". 

Who can trust a single word Aggregate Industries' consultants say any more?

How can local people be expected to make sense of this nonsense?

In a letter of 7 April 2021, Aggregate Industries wrote: 

We would now ask that our application is progressed to the next available committee and confirm our agreement to a time extension until the 30th September 2021 in order to achieve this.

Has the company given up caring whether its application to quarry Straitgate Farm makes any sense? As we’ve posted, major fundamental issues have still not been resolved, not least on the issue of surface water and how a scheme could be produced that satisfies the interconnected issues of flooding, stream flow, groundwater recharge, and airport safeguarding – without losing even more resource. 

But it’s not just that. The documentation is a shambles. It’s difficult to see how any consultation could be valid given the quagmire of contradictions. It’s difficult to see how any subsequent decision taken at committee could be robust. 

For example: The Supporting Statement for the Straitgate Farm application should be one document that can be relied upon – but not so. The document reminds us that: 

8.2. This application is inextricably linked to another planning application to import the sand and gravel from Straitgate Farm into Hillhead Quarry. 

The Hillhead Supporting Statement echoes that: 

1.1.2. This planning application is inextricably linked to another separate planning application to win and work 1.5 million tonnes of sand and gravel at Straitgate Farm. Both this application and the Straitgate Farm application are supported by a common Environmental Statement. 

And a common Environmental Statement may be how things this started, but matters have moved on. 

Aggregate Industries says the July 2018 Transport Assessment – the one now being consulted on – "supersedes previous assessments", but it makes no assessment of the impacts of the multi-million mile haulage plan to Hillhead. That job falls to the previous, superseded TA, the one still live for the Hillhead application. Confused? That TA is now seriously out of date: the traffic count for Clay Lane is from 2016, the count for the M5 from 2015; the collision data up to the end of 2015. However, it does claim: 

7.5 Processed material will be sold into the local aggregates market. Approximately 90% of material will be sold into the Exeter market travelling via the A38 and M5. Approximately 10% will be sold into markets adjacent to Hillhead accessed via the A38. 

This is in clear disagreement with the new Greenwash Report which assumes – in order to show that hauling material 46 miles for each load is magically the most sustainable option – that only 34% heads to the Exeter/M5 market. 

The Straitgate Supporting Statement cites the widening of Clay Lane to be "of great benefit to residential amenity and carry significant weight in the decision making process" and furthermore that: 

5.4.8 Critics will, no doubt, point to the distance which the Straitgate Farm minerals will need to travel to Hillhead for processing and, if current market conditions prevail, the distance those processed minerals will have to travel to their end destination. 5.4.11 The Applicant considers that the highway infrastructure improvement measures included in both planning applications are sufficient to outweigh the negative impact of transporting the Straitgate minerals to Hillhead Quarry for processing and, therefore, overcome the apparent conflict with Policy M22.

The application was originally advertised and consulted on that basis. Indeed, the Hillhead Supporting Statement crows: 

7.12. The planning application to import Straitgate Farm mineral into Hillhead Quarry for processing was generally very well received, particularly the proposal to widen a 400 metre section of Clay Lane to accommodate two way traffic.

Even the planning red line boundary for the Hillhead application still includes:

The problem? The application to widen Clay Lane was approved separately in 2018. The stated benefits can no longer support the Straitgate application, to "overcome the apparent conflict with Policy M22". So why has the Supporting Statement not been updated to spell out the correct situation? 

Clearly the public have been consulted on incorrect information, clearly councillors risk being misled. 

It doesn’t stop there. Straitgate’s Supporting Statement claims:

8.7. The maximum number of vehicle movements generated as a result of this proposal is 86 loads per day, or 172 movements per day.

This is mirrored in Hillhead’s Supporting Statement which says: 

3.4.2. The maximum number of loads from Straitgate Farm to Hillhead Quarry is 86 per day.

Does Aggregate Industries know what maximum means? The TA that "supersedes previous assessments" claims: 

6.1.2 During intensive periods of working this would have the potential to increase to 216 HGV trips per day...

And what about the poor pedestrians? Straitgate’s Supporting Statement claims: 

3.4.5 In order to allow pedestrians using Birdcage Lane a route which avoids any interaction with lorries accessing the site, it is proposed to install a permissive footpath running parallel with Birdcage Lane just inside the tree belt around the periphery of the fields from the Exeter Road junction northwards... 

The new draft S106 formalises this: 

i) AIUK shall create a new permissive footpath adjacent to Birdcage Lane as shown on plan referenced SF/2 Rev B prior to the commencement of quarrying operations and maintain such permissive public footpath for the duration of the permitted development.

Brilliant. But quite how a new permissive footpath opening up near the site entrance – an entrance with up to 216 HGV movements per day – and connecting with OSM Footpath 87 to the south and east, OSM Footpath 88 to the north and WH Footpath 1 to the south, "avoids any interaction with lorries accessing the site" is anybody’s guess. 

And then there’s the orchard. Aggregate Industries has taken an unnaturally keen interest in the Straitgate Farm Orchard. Straitgate’s Supporting Statement claims: 

3.8.14 Immediately to the south of Straitgate farmhouse is a dilapidated orchard. The orchard is shown on Ordnance Survey Maps dating back to the late 19th century and could be considered as an important part of the setting of the grade II listed farmhouse. 3.8.15 The Applicant recognises the value of the orchard both to biodiversity and to the heritage asset and proposes to restore the orchard to its former glory by propagation from existing apple trees, growing them on and replanting in a grid pattern. Cuttings will ensure local providence and the restored orchard will provide an attractive feature. 

How many cuttings would be taken to restore the orchard? "Cuttings will be taken from 10 trees as agreed with the nursery." 

Fab. So, why does the new Greenwash Report assume that "17,200m2 of restored orchard" would be planted "at a density of 2,250 trees/Ha" – a staggering 3,870 trees that would supposedly sequester annually an impossible "9.3 tCO2e"? 

The problem doesn’t stop at the orchard. Straitgate’s Supporting Statement claims: 

3.8.18 Consultation with the CAA ecological advisers has indicated that satisfactory mitigation will be achieved to negate the potential for bird strike if the proposed vegetation height can be restricted to 4-5m which is the height typically attained after some years by the shrub species proposed for the planting scheme. Additionally, they recommend restricting the spatial extent of tree planting to copses, hedgerows and shelterbelts as opposed to extensive woodland planting, and the proposed restoration planting scheme follows this advice.

So again, given those restrictions, why does the Greenwash Report assume a planting density of 2,250 trees/Ha, a stocking density typically employed for conifer forests? Clearly the report’s author knows as much about tree planting as he does about the available gravel at Hillhead. 

All in all, the whole thing's a mess. 

AI’s downgraded resource means Straitgate planning application “benefit” misstated

According to Aggregate Industries' new resource statement, the resource available at Straitgate Farm has been downgraded again, and now stands at: 

1.06 million tonnes of saleable aggregate (1.33 million tonnes of as raised (unprocessed) aggregate to be hauled from the site)

Back in March 2017, Aggregate Industries had claimed: 

3.9.1 The proposed development would release 1.5 million tonnes of as-raised sand and gravel equivalent to 1.2 million saleable tonnes of quality aggregate into the Devon marketplace

However, in July 2017, we warned that AI’s extraction plans are now down to 6 fields and 1.1 million tonnes; in fact, 1.13 million saleable tonnes to be exact – based on Aggregate Industries’ own numbers. 

This figure has now been revised down yet again, after the "maximum" water table – the base of any quarry – turned out not to be the maximum at all and had to be revised upwards.    

So, as the public are pushed through yet another consultation, we find that even the descriptions of Aggregate Industries’ two in-tandem proposals – "Extraction of up to 1.5 million tonnes of as raised sand and gravel..." and "Importation of up to 1.5 million tonnes..." – are incorrect and misleading.

And that goes for the myriad of documents referencing such numbers too.

Because there are not "up to 1.5 million tonnes". The "benefit" of each application is being exaggerated. 

In fact, if 1.5 million tonnes were ever quarried at Straitgate the maximum water table would have been breached, against conditions proposed by the Environment Agency. 

The resource at Straitgate Farm is down from 20 million tonnes in 1965, down from 7.25 million tonnes in 2011, down from 3.6 million tonnes in 2012, down from 1.66 million in 2015, down from 1.2 million in 2017, and is now 1.06 million. It’s an amazing amount to lose, down 36% since 2015 alone.    

And Aggregate Industries hasn’t even started digging yet. Typically when the diggers do start they lose even more – as evidenced locally at Venn Ottery, Marshbroadmoor, Houndaller, and Chard Junction.    

And judging by the number of times the "maximum" water table has been exceeded, the base of any quarry would in all likelihood have to be raised again.  

Aggregate Industries now claims: 

In respect of the revised Mineral Resource Assessment based on the latest modelling of the Maximum Winter Water Table the revised figure of the reserve is still over 1 Million saleable tonnes which will make a significant contribution to the supply of sand and gravel within Devon and will help to maintain the adequate and steady supply that this allocated site was identified to deliver as part of the adopted Devon Minerals Local Plan.

But even that statement is wrong. It’s not a reserve. On this side of the debate, we’re still talking about a resource, and an ever shrinking one at that.   

And that shrinking "benefit" is the one Devon County Council must weigh against the increasing list of problems – the irreversible damage to water supplies, the 2.5 million mile climate-damaging haulage plan, the heady and as yet unassessed mix of up to 216 extra HGVs a day and 4x daily cattle crossing on Ottery’s busiest road, the grubbed up ancient hedgerows, the felled veteran oaks, the loss of prime agricultural land and the setting of a Grade II listed Devon longhouse, the increased risk of flooding from infiltration plans that can't work, and a whole host of other issues.

TA: ‘HGV’s will only be permitted to travel south on Birdcage Lane’

We’ve wondered before whether anyone sense checks Aggregate Industries' documents. Does this blooper take the prize? 

The newly submitted Transport Assessment was written in 2018. Aggregate Industries & Co. have had 3 years to check it. It's even at Revision E. And yet, this clanger: 

4.3 Proposed Access Arrangements

4.3.2 The access will comprise a 6.0 m wide road with the junction formed by a 15 m bellmouth radius to the south and 6 m radius to the north; the smaller radius reflects that HGV’s will only be permitted to travel south on Birdcage Lane. 

Which from our perspective, and others who have objected to this madcap proposal, would seem perfect – but some might wonder how HGVs would actually get into the site. 🤔 

These documents are clearly meant to tick boxes, not be read.

AI would use ‘reasonable endeavours‘ to provide replacement water within 24 hrs. Why does Straitgate’s S106 give less protection to water users than Greystone’s?

Picture the scene. People living around an East Devon farm have enjoyed uninterrupted spring water for generations. Then along comes a hungry aggregates business, digging down to goodness knows what depth, causing goodness knows what problems to drinking water supplies.

Think it couldn’t happen? An eminent hydrogeologist has warned such a scheme would cause ‘irreversibly damage’ to water sources. 

Devon County Council and Aggregate Industries have a plan, a Section 106 – a legal safeguard should such problems arise.

By including a Draft Heads of Terms S106 with the planning application to quarry Straitgate Farm, Devon County Council, the Environment Agency and Aggregate Industries clearly accept the possibility of harm to water supplies to more than 100 people, to livestock farms, to a Grade I listed tudor manor house with mediaeval fishponds, to wetland habitats in ancient woodlands. 

It is therefore crucial – given what is at stake, and for the wellbeing of all those people and businesses – that the S106 wording is fit for purpose. Is it? Be the judge.  

How much effort would the company expend in putting things right? The company says it would use "reasonable endeavours": 

In all cases AIUK shall use all reasonable endeavours to ensure where required arrangements (whether temporary or permanent) shall be put in place for alternative supplies within 24 hours of being notified by the MPA or the Environment Agency or an interested Third Party.

Why "reasonable endeavours"? Why not "best endeavours"? 

A "reasonable endeavours" obligation is the least onerous type of endeavours clause. Crucially, the obligor is not normally required to sacrifice its own commercial interests and may be entitled to consider the impact on their own profitability… 

Amazing. Not being prepared to pull out all the stops for people who have lost their drinking water is disappointing, to say the least. What happens elsewhere? The S106 for Aggregate Industries' Greystone Quarry in Cornwall is phrased rather more generously:

In the event that there is interference or contamination with any of the private water supplies... then [Aggregate Industries et al.] shall forthwith at its own expense, as soon as reasonably practicable, and in any event within 24 hours, make temporary or permanent arrangements for the provision of alternative or additional water supply to the users of the private water supplies...

But what if Aggregate Industries, with its massive water-disturbing-hole-in-the-ground, should say "Not our problem, guv"? Then what? 

If AIUK shall dispute that such contamination interference or inability to draw a satisfactory water supply is partly or wholly attributable to the winning and working of minerals within the subject land and the question is referred to arbitration…

Arbitration? 

Any dispute between the parties on any matter arising under this agreement shall be referred to an Arbitrator for arbitration in accordance with the Arbitration Act 1996...

That would certainly be a nice job for a pack of lawyers and experts, and would take goodness knows how long. Years? Aggregate Industries is unlikely to take things lying down. 

But what about how? Consider a livestock farm and all its fields, how would that be provided for? How would alternative water supplies be provided to a Grade I listed house and its mediaeval fishponds, or to wetland habitats in ancient woodlands? How would alternative supplies be deployed in a rapid manner, given many of these are miles from a mains supply? 

Without knowing how, the Council is unable to properly assess this little scheme. According to a top planning lawyer: 

If there’s a problem which might be caused by the development, the LPA must know how that problem will be mitigated, and then assess such mitigation.

So, in all the time Aggregate Industries has had to prepare for its planning application, we are still not told how. How can we be sure the company knows how? What happens elsewhere? The S106 for Greystone does talk about some of the hows:

4.8 In the event of a decline in yield as indicated, AIUK would take responsibility for the "immediate provision of a temporary water supply" (e.g. water bowser). This would be kept in place until a long-term solution could be provided, as follows: 

4.9... 

4.10... 

4.11... 

And what about usage charges? Who would pay these if connection to the mains were possible? Nothing is included in the S106 about that, despite this email from Devon County Council to Aggregate Industries’ consultants back in 2015: 

Please also note that those on private water supplies may not wish to be connected to the mains and may wish for a more natural supply from a new borehole or well. Additionally, the provision of a 30 year mains water supply may not be considered acceptable to those who currently enjoy free water. If a natural free source is lost then the responsibility for its replacement should be taken on in perpetuity. 

What happens elsewhere? Let's look at that Greystone S106 again:

The fallback position would be the provision of mains water. AIUK would cover the costs for mains water connection and usage at any property where the water supply is affected by the quarry development.

So why is Straitgate different? Are there too many people dependent on water from the site? 

What is Devon County Council's input in all this? Has it had any say? It looks like it has, according to this email to Aggregate Industries, released through an FOI, from March 2019:

My next job is to send over some commentary on the draft s.106 HoT – I have been looking at the Greystone s.106 which also has some interesting points.

So it’s disappointing we’ve ended up where we are, particularly given that Devon County Council wrote to Aggregate Industries in January 2019 suggesting:

As you are aware I am waiting for an updated heads of terms setting out properties to be monitored and you may wish to consider the points raised given your confidence that the proposed development would not impact on third party water supplies? We have had this discussion about the s.106 being generous with those concerned landowners if you are confident in your hydrogeology assessments and I would suggest that this is indeed reflected in the detail of the s.106 agreement. It would certainly help to address one of the most likely causes for concern for the determining committee. I believe that the legal agreement for the management and monitoring of water supplies needs to be complete before determination and not just a general heads of terms. The way it works is going to be a material consideration and we need the detail as I have previously indicated.

And what are we now being consulted on? An ungenerous draft general heads of terms, bereft of any detail, short of any comfort. Much of the wording is still as it was in 2018, in this Regulation 22 response,  when a top planning lawyer described it as "unfit for purpose". 

At paragraph 2.8.1(i), draft wording has been proposed setting out the circumstances under which the applicant would be required to provide alternative water supplies and/or compensate for the disruption. With respect to the lawyer who (presumably) drafted this provision, it is so full of caveats, provisos, legal tests, consultation requirements and optionality as to be unfit for purpose.

What does Aggregate Industries say? In an email to Devon County Council in February 2019: 

The wording in 2.8.1(i) were those provided by Devon County Council and AIUK have agreed to the principle. The wording could no doubt be improved but this is something perhaps for DCC to address. AIUK will require all the caveats, provisos, legal tests etc in order to protect our interests and to ensure we only need to respond, in the unlikely event, to problems we have caused. 

Which tells you everything you need to know. 

How would the whole thing be policed? How frequently would the maximum water table be reviewed?

The annual report would be provided to the MPA and the Environment Agency for each year of the life of the permission by the 28th February the following year. 

Once a year, for a company with a record of non-compliance with previous Section 106 agreements concerning water? One Devon County Council monitoring report in 2018 claimed "No report on File since 2011", despite the S106 conditioning that hydrological reports were to be submitted annually. Once a year, for a site where the maximum water table keeps being exceeded. Once a year, where if the water table had been exceeded the previous spring, and diggers had continued digging below the water table, no one would be any the wiser. 

How much is at stake? Quite a bit actually. 

A planning lawyer has now had the chance to study the proposed S106 and concludes:

the draft heads of terms proposed by the applicant are woeful and worrying in equal measure... One does not need to be a lawyer to recognise the enormous and unacceptable scope for delay and legal argument in the above draft heads. The draft terms are littered with phrases which immediately doom the effectiveness of the maintenance provisions, such as "in the opinion of", "in consultation with", "on the balance of probability", "satisfactory supply", "necessary or appropriate", "to the extent that the same is attributable", "all reasonable endeavours". Not content with such a litany of subjective legal phraseology, there is also a draft term – the nail in the coffin - allowing recourse to arbitration (which itself is one of the slowest methods available for dispute resolution) in the event that AIUK dispute there being a problem with the water supply. In terms of ensuring a safe and continuous water supply post-permission, the draft heads are, to all intents and purposes, categorically and undeniably unfit for purpose. … The scale of the problems which will be caused to Cadhay by the proposed draft obligations is potentially devastating. By way of mitigation of these substantial risks, though, AIUK offers delay, legal wranglings, obfuscation and everything but direct and immediate action.

We need to be preserving English oaks, not cutting them down

This oak tree is what Aggregate Industries’ consultants call T5. 

It is the smallest of the oak trees likely to be lost by a quarry at Straitgate Farm.

Aggregate Industries claims: "Three mature oak trees will be lost to the development, two of which grow within hedgerows and one located within a field". This ignores Trees F, G and H which are "likely [to] be damaged by the development and need to be felled." 

In all, six mature oaks are likely to be lost, as well as two substantial beech trees and other mature trees during site access works. Aggregate Industries’ consultants dismiss these trees as having “little impact on the amenity of the area”. 

What will replace them? In Aggregate Industries' alternative universe, the land of smoke and mirrors, the ripping out of 1.5km of ancient hedgerow up to 4m wide – habitat for protected dormice and bats – and the felling of 6 mature oak trees, replacing natural history hundreds of years old with saplings and tree tubes, will show a net biodiversity gain! It defies logic and common sense. 

And, oh yes. "A minimum of ten oak trees will be planted and allowed to grow to maturity." How very generous.

AI to drill boreholes at Penslade for ‘monitoring of the watertable’

Last week, Aggregate Industries was granted permission, DCC/4235/2021, to drill nine boreholes at Penslade, a site adjacent to Hillhead near Uffculme, that – like Straitgate Farm – is designated a Preferred Area for sand and gravel extraction in the Devon Minerals Plan, but – unlike Straitgate Farm – has 8 million tonnes and is 23 miles closer to the company's processing plant. 

In fact, where Straitgate would yield less than 1 million tonnes of material – if the company ever works out how to design effective infiltration areas – the area around Penslade Farm would give Aggregate Industries access to some 23 million tonnes – more than 70 years' worth based on sales of 300k tonnes per year. The statement below, from the Minerals Plan, hardly needed saying:

Policy M12 proposes two new locations for mineral working... In the event that Straitgate Farm proved to be incapable of being delivered, then the other site, West of Penslade Cross, would have adequate resources to enable sand and gravel supply to be maintained for the Plan period.

Most of this area is owned by Aggregate Industries. In relation to the boreholes, the company says: 

The boreholes will be between 23m and 38m in depth and piezometers will be installed to enable the monitoring of the watertable as required by the Devon Minerals Local Plan.

The Minerals Plan specifies "groundwater monitoring for a minimum 12 month period." 

This has been in the pipeline some time. In 2017, we posted Plans to install piezometers at Penslade: 

at a meeting last week, AI's Head of Geological Services confirmed that budgets are now in place to install piezometers at Penslade… 

You might ask, however, why these plans were only submitted in the middle of a consultation to quarry Straitgate Farm, a proposal that would see minerals worked "over a period of between 10 and 12 years" and would not start until 2023? Was it coincidence, or did Aggregate Industries sense things going pear-shaped with the Straitgate application again? 

In 2017, on being questioned about Penslade by Devon County Council, Aggregate Industries reckoned: 

It is envisaged that groundwater monitoring will be undertaken for a minimum of 3 years prior to submission of a planning application in some 5 years hence.

but went on to say that the site "subject to planning, would come on stream approximately 2030."

Aggregate Industries will obviously be hoping for more success with Penslade than with Straitgate, where boreholes were first drilled in 2013, and where 8 years later, in 2021, the company is still floundering. In its first application for Straitgate back in 2015, Aggregate Industries had been hoping on the site "being available from early 2016". It wasn't to be. The application was pulled following a complete fiasco. In March 2017, another application was submitted with the hope that mineral would start being imported from Straitgate into Hillhead Quarry by "mid 2018". 

The fact that Aggregate Industries has been able to function quite happily for the last 5 years with just the sand and gravel from Houndaller – a reserve of some 2.9 million tonnes at the last count, enough to last for 10 years – clearly means it can survive quite happily without Straitgate.

Responses to AI’s submission of further information

Aggregate Industries’ latest submission of information in relation to its planning application to quarry Straitgate Farm, has prompted numerous concerns by members of the public. Some notable objections include Devon County Councillor Jessica Bailey, the Devon Gardens Trust, and the legal representative of Cadhay. Our response can be found here. 

The Environment Agency's response has been deferred pending a meeting with Professor Brassington, which will also be attended by Devon County Council, Aggregate Industries and consultants Wood.

As things stand, the EA’s drainage condition couldn't be satisfied

How surface water would be dealt with in any proposal to quarry Straitgate has fundamental implications for flooding, groundwater recharge for springs and water supplies, stream flows and airport safeguarding. 

Even Aggregate Industries recognises pre-emptive planning is key to flood defence:

The Great British weather has only become more erratic in recent years, with torrential storms and heavy rain frequently causing widespread flooding and misery – and the reality, unfortunately, is that it is likely to get worse. 

The issue at Straitgate is so sensitive that the Environment Agency has already said that a number of conditions "must be secured on any planning permission", including: 

8. The working and restoration infiltration design shall ensure that drainage mimics the pre-excavation drainage. This shall be achieved following the principles described in the July 2017 Hydrogeology/Drainage Regulation 22 responses report.

But as we’ve already pointed out – here, here, here and here – Aggregate Industries’ infiltration plans could not work as described, post-extraction drainage could not mimic pre-excavation drainage. 

This issue stretches back a long way. It’s not as if Aggregate Industries hasn’t been warned. 

In 2015, the Environment Agency said: 

The development should be designed so that drainage from the site mimics, as closely as possible, the natural hydrograph in perpetuity – this will ensure that the hydrographs of springs and water courses in the area are not adversely impacted. 

In 2017, the Environment Agency was concerned that the company had not resolved the issue: 

We object to the planning application, as submitted, because the applicant has not supplied adequate information to demonstrate that the risks posed to groundwater can be satisfactorily managed. We advise that this further information should be requested under Regulation 22 of the Environmental Impact Assessment regulations. 

On infiltration areas, in particular: 

8. The working and restoration infiltration design should be described in detail. How will it ensure that drainage will mimic the pre-excavation drainage? 

A Regulation 22 request was duly made by Devon County Council. A meeting was held between personnel from the Environment Agency, Aggregate Industries and its consultants. Minutes were produced. On the subject of infiltration areas: 

MW [from the Environment Agency] said that the final restoration profile should mimic the current one so as to ensure recharge is not inadvertently moved from one sub-catchment to another thereby ensuring the headwater flows remained similar.

Aggregate Industries produced a response, "the July 2017 Hydrogeology/Drainage Regulation 22 responses report." Don’t worry, they fibbed: 

2.9.4 The majority (i.e. 2/3) of the planned extraction area will be at either post-restoration or pre-extraction stage, with natural runoff patterns following the slope gradient, and infiltration to the relevant sub-catchment. 2.9.8 The restoration has therefore been designed to ensure the site is restored to baseline conditions (i.e. ‘mimic’ them), with some betterment provided where possible. 

It was fiction. The final restoration profile could not mimic the current profile; there would not be "natural runoff patterns following the slope gradient" given that the base of any quarry, the revised MWWT – the blue contours – does not mimic the existing topography – the brown contours – as shown below:

And the 2/3 claim? Could just 1/3 of the site be worked at any one time? Of course not.

It is proposed to quarry Straitgate in three phases. When it comes to Phase 3, the Flood Risk Assessment says: 

3.2 Phase 3 area... Soils will be placed onto the Phase 1 area to restore this area to final the landform... Overburden will be placed within Phase 2 area, with the exception of the eastern infiltration area which is to be left open. 

In other words, as phase 3 is started, phases 1 and 2 have not yet been restored. And this is still what’s proposed, according to the newly delivered Soils Management document. i.e. 

For phase 1: 

This stage is illustrated by Drawing SF / 5-1 Rev B. The soils that are stripped from this initial phase may remain in store for a period of approximately 10 years… 

For phase 2: 

Some of the soils from Phase 2 may need to go into storage and extend the original Phase 1 bunds in the east of the site. The soils that are put into storage from this second phase may remain in store for a period of approximately 8 years… 

For phase 3:

All of the soil resources from Phase 3 will then be direct placed into the previously worked out void, as shown in Drawing SF / 5-3 Rev B. 

Again, all phases being worked at the same time – not 2/3 "at either post-restoration or pre-extraction stage". In fact, by the end of phase 2, 2/3 of the site would be excavated, and would stay this way until the end of phase 3. It was a simple thing, but Aggregate Industries still couldn’t come clean.

AI’s surface water plans rely on 3rd party culvert – and revised MWWT contours show more water would be directed towards it

Don’t laugh, but Aggregate Industries' plan for Straitgate Farm – the one it’s been working on for the last decade – is reliant on someone else's small, easily-blocked, 300mm culvert.

A large portion of surface water run-off from any quarry at Straitgate Farm would be discharged to the Cadhay Bog watercourse, via the above third party culvert that runs underneath a neighbouring field.

This issue has been around some time. In 2013, Aggregate Industries' consultants concluded:

There is extensive evidence of natural flooding across the eastern extent of Straitgate Farm. The capacities of roadside ditches and streams have not been adequate to deal with recent levels of rainfall in the area. 

In 2015, for Aggregate Industries' previous application, the Environment Agency recognised in this Devon County Council Regulation 22 document that the existing culvert would need to be improved "to reduce the risk of flooding, which has been seen to have a significantly adverse impact on surrounding settlements." A meeting was held: 

It was agreed by DCC and the EA that the previous comments regarding de‐culverting off‐site watercourses which had been made on biodiversity grounds would not be pursued as there was a possibility that this could increase downstream flooding. 

In any case, Aggregate Industries claimed the issue wasn't anything to do with them, because they wouldn't increase the amount of surface water running off the site: 

3.12 Improvements to the existing drainage should focus on increasing roadside ditch capacity and ensuring that culvert inlets and outlets are suitably maintained to avoid blockages from vegetation or siltation. 3.13 There is a need for work on the existing drainage beneath Birdcage Lane to improve conveyance and prevent episodes of flooding along the road, this should however be the statutory responsibility of the local highways department if it can be demonstrated by AI that watercourse peak flows are not increased by extraction activities at Straitgate Farm.

And no increase in surface water run-off is what Aggregate Industries is still attempting to claim:

2.13.7 Two discharge points are proposed: One serving the ancillary area and upper portion of the access road north of the Cadhay Bog Stream which will discharge directly to the watercourse at ‘Point A’ on Figure 2.6 below; and The remaining section of the access road south of the Cadhay Bog Stream will discharge to the roadside ditch in the far south-east of the site, which drains northwards to join the Cadhay Bog stream, as shown on Figure 2.6 as ‘Point B’. 2.13.8 This arrangement ensures that the runoff from these developed areas (ancillary area/access road) is managed within the Cadhay Bog sub-catchment, and the final rate and volume of flow discharged to the Cadhay Bog stream replicates the natural rate and volume. 

But that's just wishful thinking. In the real world, with extreme weather events becoming more unpredictable, and with a quarry upslope removing the majority of the unsaturated layer, who knows what would happen? What allowance for improving this culvert has been made in this application? None. And it doesn’t matter how many discharge points there are, both Point A and Point B would feed into the one 300mm culvert: 

Given that it was recognised this culvert struggled to take the existing run-off from the site, it was surprising that the introduction of a quarry in its upslope catchment, together with access road, 50mx50m loading/stocking/lorry parking area, wheel wash, weighbridge, tip off bay, and lagoon (variously described as 1,286m2 to less than 600m2, or 20mx20m) had not prompted a little more thought.

But with the recent submission of revised maximum winter water table contours – the proposed base of extraction – matters have taken a new twist. 

We have already posted that the revised base of extraction does not mimic existing ground elevation contours to maintain pre-extraction run-off characteristics. 

Overlaying the revised MWWT contours over the Extraction and Ancillary Development plan shows that the base of extraction would direct more surface water to the Cadhay Bog water course than existing ground levels. More surface water would flow towards the loading area, down the swale adjoining the access road, into the lagoon, and towards the ditch on Birdcage Lane.  And all of that would then need to pass through the one 300mm culvert.

What could possibly go wrong?

The Flood Risk Assessment has made no allowance for increased run-off from the revised extraction contours. The swale capacity makes no allowance for this. The lagoon capacity makes no allowance for this. The ditch capacity along Birdcage Lane makes no allowance for this. The 300mm culvert makes no allowance for this. Clearly, it's another major failing.

And how much water can already flow down the Cadhay Bog watercourse on a bad day?