FAQs
What is currently happening at Rock Common Quarry?
Rock Common Quarry is an active sand quarry. The sand that is dug from the quarry is fed into a hopper and transported by a conveyor belt system under The Hollow, to a ‘processing area’ where it is ‘washed’ and/ or ‘graded’ and left to dry before leaving the site.
Sand has been extracted from the quarry for over a century. In recent years the average amount of sand extracted from the site has been about 50,000 tonnes per year, but has been as high as 300,000 tonnes in the past.
Is there any more sand to extract?
Most of the usable sand from the quarry has now been extracted. It is estimated that there is up to a further 150,000 tonnes of sand reserves that remain in the quarry to be extracted.
What is the current scheme to restore the quarry?
The quarry is operated in accordance with a planning permission granted in 2004 (reference WS/15/97). This planning permission includes a subsequent ‘restoration’ scheme.
This involves reducing the steepness of the sides of the quarry (to 50 degrees) and filling the hole that has been created by sand extraction with water. The maximum water depth would be about 30m.
Why can’t the current ‘approved’ restoration scheme take place?
There are a number of difficulties with the approved restoration scheme. It no longer reflects best practice, because very deep lakes with steep underwater slopes are dangerous, and of little biodiversity benefit.
The main problem is that the lake would be likely to become contaminated. The quarry is close to the former Windmill landfill area, located on the north side of The Hollow. The way this landfill was created means that it is very likely that contaminated liquid (leachate) would travel through the ground from the landfill site and end up in the waterbody of the quarry. This would pollute the lake.
Why can’t Rock Common Quarry just be left as it is?
The bottom of the quarry is well below the level of ‘groundwater’ in surrounding land. This means that water is permanently entering the quarry. At the moment, this is pumped out of the quarry on a regular basis, to prevent the quarry filling with water.
If the quarrying and water pumping stopped, the quarry would naturally fill up with water. This waterbody would become contaminated for the reasons explained under the Question ‘Why can’t the current ‘approved’ restoration scheme take place?’.
What are the alternative restoration options?
A number of different restoration options for the site have been considered.
An option is to restore the site in accordance with the approved plans. The problems with this Option have been set out under the Question ‘Why can’t the current ‘approved’ restoration scheme take place?’.
An alternative option is to ‘do nothing’ once the sand extraction has finished. The problems with this Option have been set out under the question ‘Why can’t Rock Common Quarry just be left as it is?’
An alternative option is to leave the quarry empty once the sand extraction has finished and continue pumping water out of the quarry. However, the current quarry sides are steep and will erode if left as they are. This would also leave a large empty hole, which would have long term risks of accidents in the event of trespass, and the 40m deep ‘bowl’ would look out of keeping with the character of the wider landscape.
Finally, there is the newly proposed restoration scheme, which mitigates these challenges above and benefits the biodiversity and wider landscape.
What is the proposed new restoration scheme and what will it look like?
The proposed new restoration scheme would create a far better landscape for nature with 3 shallow lakes with gently sloping edges.
It includes the importation of soils to raise the ground level in the quarry so that it is above surrounding groundwater levels but below the edges of the quarry. A series of new shallow lakes would be formed. The scheme would create a haven for biodiversity and provide public access.
It is intended to use part of the site as a visitor destination, co-located with ecotourism accommodation to form a gateway to explore the local area, including the South Downs National Park. This element will be the subject of a separate application in due course.
Why is the new restoration scheme the best option?
Due to a combination of the depth of the quarry, the level of surrounding groundwater, and the proximity of the adjacent former Windmill landfill site, the approved restoration scheme, or a ‘do nothing’ option, would be likely to lead to contamination of the water that would fill the quarry.
The best way of resolving this is to raise the ground level in the quarry so that it is above the surrounding natural groundwater level. This will prevent water pollution that would otherwise be likely to occur.
The new proposed restoration scheme, would also provide a much better biodiversity haven, with public access.
When will work start on the new restoration scheme and how long will it take to complete?
Work on the new restoration scheme would not start until planning permission has been granted. It is hoped this will occur this year.
It is likely extraction of the remaining sand reserves would continue for about 3 years. In parallel with this, work on the restoration scheme would start in 2022.
It is estimated it would take 8-10 years to complete the restoration work.
How much soil will be brought into the quarry and where will it come from?
The new restoration scheme requires about 2.7 million cubic metres of soils to be brought into the site. Up to about 345,000 cubic metres of soils would be brought in each year.
The soils would be clean and ‘inert’ and typically be sourced from construction projects, such as soil dug out to make way for foundations for new houses.
These soils arise in areas of new housing and construction projects, and are likely to be predominantly sourced within a 10 mile radius of the site.
How will the soil be delivered to the site?
The soil would be delivered to the site by road, using tipper trucks. Each truck can carry about 9 cubic metres of soil.
How much traffic will there be and what route will it take?
Sand extraction and processing is proposed to continue from the site for about 3 years. Access to the quarry for this use would be via the A24 only. This reflects the existing operating arrangements, which are controlled by planning condition.
The restoration scheme requires about 2.7 million cubic metres of soils to be brought into the site. It is estimated that up to 345,000 cubic metres of soil would be delivered each year. This would be delivered by tipper trucks which are each able to carry about 9 cubic metres of soil. There would be an average of about 150 inbound trips (300 total two-way trips) per day.
All vehicles delivering soils to the site (and subsequently leaving) would be along The Hollow, via the A283. The majority would be travelling to, and from, the Washington roundabout.
Because these materials are being brought in from local areas these vehicles will already be on the road and Rock Common will enable a local destination for inert material to be recycled and reused.
How will soil get into the quarry?
Soils would be delivered to a reception area that is to be created on the north side of The Hollow. This area has an existing lorry access. There is an existing tunnel under the road that would contain a conveyor belt to transport the material into the quarry. Once it is in the quarry it will be moved by machine to its final position.
What will be the hours of work to create the new restoration scheme?
The hours of operation of the existing quarry operation are limited (by planning condition) to 07:00-18:00 Monday to Friday; 07:00-13:00 on Saturdays; and no operations are permitted on Sundays or public and bank holidays (except for water pumping, and maintenance of plant and equipment).
Works associated with the proposed restoration would be limited to the same operating hours.
Will it be noisy or dusty?
There are existing planning conditions which control the level of noise that can be emitted from the site. It has been calculated that noise arising from the proposed restoration scheme would be below these existing noise controls levels.
The potential impact of dust from the scheme has also been carefully considered. It has been concluded that in general, there would be little impact arising from dust, including from associated traffic.
Mitigation measures have been recommended for a small number of properties that are very close to the quarry. These include how material is stored, using compacted roadways within the quarry, limiting vehicle speeds within the site, using wheel washing facilities, and placing screens around specific areas of the site where works are taking place close to the top level of the quarry.
What will be the effect on wildlife?
As part of the preparation of this application there have been extensive surveys of existing flora and fauna within and around the quarry. This has confirmed the presence of a number of bird species, (including some rare species), mammals, reptiles, insects and amphibious species.
The impact of the proposed restoration scheme on these species, has been carefully assessed. A range of measures have been proposed as part of the restoration scheme to protect existing species and/or provide replacement habitats.
The new proposed restoration scheme aims to have a positive impact on wildlife, in comparison to the approved restoration scheme. The shallow lakes will create a unique habitat in the local area and provide habitat for a much more diverse ecosystem than the currently approved scheme.
Will it affect the South Downs National Park?
The quarry is located close to the northern edge of the South Downs National Park. The quarry is visible from the higher parts of the downland, including close to Chanctonbury Ring.
The proposed restoration scheme would provide a final landscape which is more ‘naturalistic’ and reflective of the surrounding area, in comparison to the approved restoration scheme, which would result in a single, large, steep-sided lake.
The proposed restoration scheme would have a positive impact on the setting of the South Downs National Park.
What is going to happen to water currently being pumped into the Honeybridge Stream?
At the current time, groundwater that naturally discharges into the quarry is pumped into the Honeybridge Stream which is close to the western edge of the site.
Under the approved restoration scheme, this pumping would cease and the water would fill up the quarry. This would significantly reduce the water flow in Honeybridge Stream, and may harm its biodiversity.
The proposed restoration scheme includes building a well-like structure. It would be used throughout the construction period to continue pumping groundwater from the quarry into the Honeybridge Stream.
Once the scheme has been completed, water could continue to be pumped through the well to maintain the flow rates in the Honeybridge Stream.
If the pumping were to cease in the future, this would be done with careful consideration of the ecology of Honeybridge stream and could be done over a number of years. The proposed restoration scheme would prevent water pollution coming from contaminated liquid (leachate) from the adjacent former Windmill landfill area.
Will there be public access to the quarry when the restoration scheme is completed?
The proposed restoration scheme would provide a network of footpaths in the restored quarry.
An existing Public Right of Way, which runs along the western boundary of the quarry, would connect to this new footpath network to provide public access to the northern part of the restored quarry, and connect to The Hollow.
The Wiston Estate intend to provide public access across the northern part of the restored quarry by creating ‘permissive paths’.
Why does this restoration scheme not show the future eco-lodges?
The long term aim of The Wiston Estate is to use part of the restored quarry as a visitor destination, co-located with ecotourism accommodation, to provide a gateway to explore the local area, including the South Downs National Park.
These details are not included in the restoration scheme, as this part of the proposal requires a separate planning application to a different Council (Horsham District Council rather than West Sussex County Council).
Details of the scheme will be prepared in the future and shared with the public as part of a separate application.
Where can I see the planning application documents and how can I comment?
All of the documents that comprise the application pack have been submitted electronically to West Sussex County Council. They will make these documents available on their website (www.westsussex.gov.uk). To make it easier to find, a link to the application documents is provided on this website, together with a summary of the key documents.
West Sussex County Council are required to publicise the application and will invite comments on it. They will set out the time period for this, as part of their advertising of the application.
Any comments that you wish West Sussex County Council to take into account, should be submitted direct to them quoting the application reference number. These can be submitted either electronically, or in writing.
