Woodsmith Mine Tunnel

From Wikishire
Jump to: navigation, search
Woodsmith Mine Tunnel
Yorkshire
North Riding
Lockwood Beck site.jpg
Lockwood Beck site
Location
Carrying: Mined material
Beneath:
Location
Grid reference: NZ713115
Location: 54°29’39"N, 0°54’1"W
Structure
Length: 23 miles
History
Built April 2019 to (ongoing)
Information
Owned by: Anglo American PLC

The Woodsmith Mine Tunnel (also known as a Mineral Transport System [MTS]) is a tunnel 23 miles long tunnel being built beneath the Cleveland Hills in the north-west of the North Riding of Yorkshire. The tunnel is to stretch between the Woodsmith Mine at Sneatonthorpe near Whitby and the Wilton International complex by the River Tees, at the northern edge of the county. The tunnel has been in development since 2016, but cutting of the tunnel bore did not start until April 2019, with an original expected finish date of 2021.

When finished, the tunnel will be the longest tunnel wholly in the United Kingdom and will also house Britain's longest conveyor: at 23 miles, the tunnel will be exceeded only by the Channel Tunnel, though the latter, underground for 35 miles, it is not wholly within the United Kingdom. The estimated cost of the tunnel in November 2018 was £1.1 billion.

Background

York Potash Ltd put forward the idea of mining potash and polyhalite on the moors above Whitby in 2010. Originally, three options for moving the mineral out were considered; a pipeline, a tunnel or a railway. Whilst the intended end location is Wilton (for delivery to the Redcar Bulk Terminal), the developers also considered the Ports of Hull and of Immingham to the south. However the geology south through the Yorkshire Wolds was prohibitive for tunnelling as the chalk bedrock carries aquifers that are important for the region and would also need extra access/ventilation shafts, create more overburden and be of a significant extra cost than a shorter tunnel to Teesside.[1] A tunnel to Hull would have had to stretch for 60 miles and need an extra 62% of tunnelling effort, time and expense.[2]

Transporting the product out by way of a railway line involved crossing the River Esk at Larpool Viaduct, and then along the Esk Valley Line via two reversals in Whitby to gain the route towards Middlesbrough.[3]

A pipeline would have involved turning the potash and polyhalite into a slurry[4] which would have required a more labour and technically enhanced process at both ends of the transport system.[5] A pipeline would also be above ground and cause a lot of environmental damage.[6]

Both the pipeline and rail options were dropped in favour of a tunnel with conveyors in it during the planning stages, and through various submissions, the accepted plan was approved in June 2015.[7] The company, now Sirius Minerals, agreed to pay £130 million to the North York Moors National Park Authority to "protect and enhance the environment". This would be over the whole life of the project.[8]

To avoid damaging aquifers across the route, the tunnel is designed to stay deep within the Redcar Mudstone Formation. The Redcar Mudstone Formation is less permeable to water and the route also avoids any former ironstone workings in the Redcar area.[9]

The cost of the tunnel was estimated at £1.1 billion in November 2018,[10] and when complete, the tunnel will be the longest that is wholly within the United Kingdom.[11] The conveyor will be robust enough to transport between 10 and 20 million tonnes of polyhalite when the mine is in full production with the raw mineral being transported to Teesside for granulation and onward shipping.[12][13][14]

Route

The tunnel will run in a north westerly direction from the Woodsmith Mine site, passing under the River Esk, the Esk Valley railway line, the A169 and then up across the Esk Valley to its first ventilation/access Point at Lady Cross Plantation. It then crosses moorland and runs alongside the A171 road for some distance crossing under it just south of Lockwood Beck reservoir where the second access point is. It then turns in a more north/north westerly direction through Tocketts Wood and under first the A173 road and then the A174 until it arrives at the Materials Handling Facility (MHF) at Wilton.[15] After granulation, the finished product will be taken on another conveyor (this time above ground) to the export site at Redcar Bulk Terminal.[16]

The company claim that the entire route does not travel under any housing, but it does come close to some barns.

Details

Proposed cross-section of tunnel
  • Length - 23 miles
  • Overall diameter - 20 feet
  • Internal diameter - 16 feet
  • Minimum depth - 394 feet
  • Average depth - 820 feet
  • Maximum depth – 1,181 feet
  • Width of conveyor belt – 4 feet
  • Speed of conveyor – 13 mph

Outside links


References

  1. YPLA 2014, pp. 106–108.
  2. YPLA 2014, p. 106.
  3. Potash prospects mean freight my return to Whitby. Key Publishing. April 2011. 15. 
  4. Flanagan, Emily (30 September 2014). "Plans for biggest potash mine in Europe submitted". The Northern Echo. https://www.thenorthernecho.co.uk/news/11505430.plans-for-biggest-potash-mine-in-europe-submitted/. Retrieved 2 May 2019. 
  5. Smale, Katherine (5 November 2018). "UK first for shaft sinking innovation at £4.2bn potash mine". New Civil Engineer. https://www.newcivilengineer.com/latest/uk-first-for-shaft-sinking-innovation-at-42bn-potash-mine/10036829.article. Retrieved 2 May 2019. 
  6. "Woodsmith potash mine: showcasing the future of underground technology". Mining Technology | Mining News and Views Updated Daily. 25 February 2019. https://www.mining-technology.com/features/woodsmith-potash-mine-underground-technology/. Retrieved 15 April 2019. 
  7. Pidd, Helen (30 June 2015). "North York Moors potash mine gets £1.7bn go-ahead". The Guardian. https://www.theguardian.com/environment/2015/jun/30/north-york-moors-potash-mine-gets-17bn-go-ahead. Retrieved 13 April 2019. 
  8. Bounds, Andrew (10 March 2017). "Sirius Minerals and the battle to build Britain's deepest mine". Financial Times. https://www.ft.com/content/e993eece-0383-11e7-ace0-1ce02ef0def9. Retrieved 15 April 2019. 
  9. "Construction". http://siriusminerals.com/our-project/mineral-transport-system/construction/. Retrieved 14 April 2019. 
  10. Morby, Aaron (12 November 2018). "Strabag confirmed for potash mine tunnel fit-out | Construction Enquirer". www.constructionenquirer.com. https://www.constructionenquirer.com/2018/11/12/strabag-confirmed-for-potash-mine-tunnel-fit-out/. Retrieved 1 May 2019. 
  11. Whipple, Tom (13 April 2019). "Colossal bore gets priest's blessing to dig a giant tunnel at Yorkshire Mine". The Times (72820): p. 22. SSN 0140-0460. 
  12. Duke, Simon (22 April 2018). "I’m digging the biggest hole in Yorkshire, says Sirius Minerals boss Chris Fraser". The Sunday Times. https://www.thetimes.co.uk/article/im-digging-the-biggest-hole-in-yorkshire-says-sirius-minerals-boss-chris-fraser-9fx2l06zp. Retrieved 2 May 2019. 
  13. "Strabag to build tunnel for £3.2bn Yorkshire potash mine - News - GCR". Global Construction Review. 3 April 2018. http://www.globalconstructionreview.com/news/strabag-build-tunnel-32bn-yorkshire-potash-mine/. Retrieved 2 May 2019. 
  14. Copeland, Alexa (23 January 2019). "Sirius Minerals unveils impressive tunnel boring machine". The Northern Echo. https://www.thenorthernecho.co.uk/business/17376477.sirius-minerals-unveils-impressive-tunnel-boring-machine/. Retrieved 2 May 2019. 
  15. "MTS Route". http://www.constructionenquirer.com/wp-content/uploads/Screen-Shot-2018-04-03-at-23.45.52.png. Retrieved 15 April 2019. 
  16. Duke, Simon (2 May 2019). "Sirius raise $425m in new share offer". The Times (((72,836))): p. 44. SSN 0140-0460.