We understand that you are likely to have questions about the proposed Keuper Gas Storage Project.  Below are answers to some of the commonly-asked questions.

About Keuper Gas Storage Limited

Who is Keuper Gas Storage?

Keuper Gas Storage Limited was granted consent to build the project. INOVYN Enterprises is the land owner and its Brine & Water Business would be responsible for the solution mining of brine to facilitate this proposed development.

Where does the name “Keuper” come from?

The rocks from this area are part of the Mercia Mudstone Group, from the Triassic era.  Of particular interest is the Northwich Halite Member, of both mudstones and rock salt.

The former (old) name for this rock sequence was “The Lower Keuper Saliferous Beds” overlain by the “Middle Keuper Marl”. So the name Keuper has a long association with the rocks of this area and the Holford Brinefield.

What does INEOS already do in the UK?

INOVYN is a wholly owned subsidiary of INEOS. INOVYN has other sites in the UK, which in the North West includes INOVYN ChlorVinyls and INOVYN’s Salt Business at Western Point, Runcorn and INOVYN Enterprises’ Brine and Water Business in Northwich as well as another site at Newton Aycliffe. INEOS has sites at Hull, Seal Sands and Grangemouth.  Across the UK INEOS and INOVYN employs more than 3,500 people.

About the Keuper Gas Storage Project

What does the proposed development involve?

The KGSP involves creating underground cavities in salt rock, using tried and tested solution mining techniques, which INOVYN and its predecessors have been using for the last 80 years. This solution mining process produces brine, which is effectively concentrated salt water.  This will largely be used for the manufacture of chemicals by INOVYN in Runcorn and other customers. The chlorine that is used to treat 98% of the UK’s drinking water, keeping it germ free, is already produced at Runcorn using brine from Northwich.

Why have you chosen the Holford Brinefield area to store gas?

Controlled solution mining has taken place in the Holford Brinefield since the 1920s. Since that time, over 200 cavities have been safely solution mined in the area, with approximately 60 cavities in use for the production of brine today. 29 of these are currently used for natural gas storage.

The safe storage of gas in salt cavities is possible where salt is at the appropriate depth and thickness to allow the creation of suitable cavities and the Holford Brinefield is ideally suited to this. INOVYN Enterprises has extensive knowledge of the geology of the area from many years of analysis and study, backed up by recent surveys. This means that specialist subsurface engineers employed by KGSL can design safe gas storage cavities.

What would it look like?

The vast majority of the proposed development, such as the gas storage cavities and pipelines, would not be visible above ground once complete, although there would be some visible activity during the construction phase. The brine / gas wellheads will be visible but are less than 4m high. The drilling rigs are typically 25 to 30 metres in height, but are only present at each wellhead for approximately one month during construction.

The most visible part of the development would be the proposed Gas Processing Plant, which would be located on land off King Street, within the Holford Brinefield, to the north of Middlewich.  The proposed plant would cover an area of approximately four hectares and details of the layout and elevations of the plant can be found in the planning application and consent documentation.

As part of the application for a Development Consent Order (DCO), Keuper Gas Storage Limited carried out a full Landscape and Visual Impact Assessment, which looked at the existing landscape in the area and the likely impact of the proposed development on the local landscape.

About the process

How will the gas storage cavities be created?

The cavities would be created using a solution mining process, which is the process of using water to extract brine from salt rock.  Once cavities have been formed and are the correct size and shape for the storage of gas, any residual brine will be removed and replaced with gas. During cavity development, the shape of the cavity is controlled using a layer of nitrogen and monitored by sonar surveys.

What happens to the brine after it is removed from the cavities?

The brine would be sent to the existing brine reservoirs at Lostock Hollows, south of Lostock Gralam, Northwich.  From there, the brine would be sent for purification at Lostock Works to remove trace impurities in the form of a white solid known as ‘brine mud’ in preparation for distribution to customers. This purified brine would then be sent to customers such as the INOVYN site in Runcorn, to produce chemicals such as chlorine for water treatment and salt for use in food.

Although most of the brine produced by the KGSP will be used by INOVYN and its customers, some of the brine that is not required may be disposed into the Weaver Navigation or Manchester Ship Canal.  INOVYN Enterprises already has the necessary permits to do this under a process regulated by the Environment Agency.

When will the proposed development switch from extracting brine from the cavities to filling them with gas?

It is expected that construction of the infrastructure will commence in 2021. Solution mining to create the cavities could start from 2023 and gas storage could be operational from 2025 onwards.


Is underground gas storage safe?

INOVYN Enterprises and its predecessors have been drilling and operating within the Holford Brinefield for generations and have safely created and operated over 200 wells. The area is already home to a number of underground gas storage facilities. These cavities are well-maintained and tightly regulated. Safety is the number one priority for both operators and regulators.

How would you test the safety of the project?

During solution mining, the operating pressure, flow rate and composition of the brine produced would all be monitored. In addition, sonar surveys would be taken of the developing cavities to show that the development is in line with design.

Prior to filling with gas, each completed cavity would undergo extensive mechanical integrity tests.

Once operational, the Gas Processing Plant would be staffed 24 hours a day and controlled using modern computer control systems. Operation of the proposed facility would be regulated under the Control of Major Accident Hazards (COMAH) Regulations by the Health & Safety Executive, which requires regular monitoring and review.

How much gas would you store?

Each cavity could store approximately 40 million standard cubic metres (around 30,000 tonnes) of natural gas in total. Some of this gas remains in the cavity to maintain a minimum operating pressure. In total, the proposed development could provide approximately 500 million standard cubic metres of working gas storage to the UK’s gas transmission system.

Economic benefits

How many jobs will be created?

The KGSP will provide up to 30 operational jobs and up to approximately 300 jobs during construction. In addition, the proposed development would help to secure the jobs of existing INEOS employees at the Holford and Runcorn sites.

Will there be any jobs for local people?

INOVYN already employs many local people at its Holford and Runcorn sites and would seek to recruit as many of the new employees as possible from the local area.

Will INEOS use local suppliers?

The KGSP will bring a number of supply chain opportunities for local businesses, many of which will be best placed to provide quick turnaround times. Further announcements on opportunities to work with the Project will be communicated as it progresses.  If you would like to express an interest in the project, get in touch.

Project Timescales

How long will construction take?

It is expected that the majority of the proposed development would take place over a four to five year period, but additional works on cavities and some infrastructure may extend beyond this period.

When will the project be complete?

It is anticipated that the construction phase of the proposed development would start in 2021 and could be operational from 2025 onwards. That said, there would be an ongoing drilling, solution mining and cavity conversion programme, similar to the current activities in the adjacent area.

Have your say

Will you be consulting on the proposals?

As part of the Development Consent Order (DCO) application, KGSL consulted the local community and other stakeholders about the proposed development. KGSL carried out a two-stage consultation process.  An informal, or non-statutory, consultation period was held in early 2014 to introduce the proposals and seek feedback.  A second, statutory stage of consultation, started on Thursday 2nd October 2014 and ran until Thursday 27th November 2014.  We welcomed feedback during the consultation and the methods of contact are still open if you require any further details about the Project.

How does the Development Consent Order process work?

Unlike a planning application submitted to a local authority, a DCO application for energy infrastructure is decided by the Secretary of State for Business, Energy and Industrial Strategy. A DCO is required because the Keuper Gas Storage Project is regarded as a Nationally Significant Infrastructure Project (NSIP), for the storage of gas. The Planning Inspectorate is the agency responsible for operating the planning process for NSIPs.

What happens to my comments once I’ve given feedback?

All comments and feedback on our proposed development were recorded and formed part of the Consultation Assessment Report, which was be included as part of the DCO application.

Who should I contact to find out more?

If you have any queries or questions about the Keuper Gas Storage Project, please get in touch via any of the following methods:

Call us: 0800 689 1095 (Monday to Friday 9.00am to 5.30pm)

Email us: info@kgsp.co.uk

Write to us:

*These contact details will put you in touch with Font Communications, who are managing community engagement on behalf of Keuper Gas Storage Limited

Copyright INEOS 2014