FOI request detail

Northern Line extension

Request ID: FOI-2995-1718
Date published: 09 February 2018

You asked

Please could you please publish all emails and letters between TfL and the Battersea Power Station Development Corporation from 1 July 2017 to Monday 22 January 2018 regarding the Northern Line extension? In particular, on the extra costs arising from the BPSDC making changes to the project’s design and who should account for them? Thanks

We answered

TfL Ref: 2995-1718

Thank you for your request received by Transport for London (TfL) on 22 January 2018 asking for all emails and letters between TfL and the Battersea Power Station Development Corporation from 1 July 2017 to Monday 22 January 2018 regarding the Northern Line extension, in particular, on the extra costs arising from the BPSDC making changes to the project’s design and who should account for them.

Your request has been considered in accordance with the requirements of the Freedom of Information (FOI) Act and our information access policy. I can confirm we do hold the of the information you require.

Unfortunately, to provide the information you have requested would exceed the ‘appropriate limit’ of £450 set by the Freedom of Information (Appropriate Limit and Fees) Regulations 2004.

Under section 12 of the FOI Act, we are not obliged to comply with a request if we estimate that the cost of determining whether we hold the information, locating and retrieving it and extracting it from other information would exceed the appropriate limit. This is calculated at £25 per hour for every hour spent on the activities described.

We have estimated that it would significantly exceed the appropriate limit to provide a response to your current request. When requests for email correspondence are received the FOI Case Management team may use a search tool called Discovery Accelerator. This allows us to conduct company wide email searches using keywords, dates and email addresses. The more specific a requester can be as to what they are looking for, the more we can narrow the search and therefore stand a better chance of a more relevant or focused result. We have carried out a preliminary email search across TfL for the information you have requested and the search returned 5050 potential ‘hits’.  Each ‘hit’ is a single email, although that email will often consist of a chain of emails containing the search term at least once.

The preliminary search was conducted on an open basis on all emails within the specified time period between TfL and BPSDC.  In this instance we could not use any keywords because using a keyword such as ‘NLE’ or ‘Northern Line Extension’ would have excluded emails on the requested subject which didn’t specifically contain either of those keywords. We therefore needed to run a full search which would then require each individual ‘hit’ to be reviewed to locate and extract any relevant information.

To help bring the cost of responding to your request within the £450 limit, you may wish to consider narrowing its scope so that we can more easily locate, retrieve and extract the information you are seeking. For example, you could specify a particular employee whom you are interested in, such as the Director Of Strategy & Network Development or the Director of Major Projects, along with one or more specific keywords as the search would be more targeted.

If you want to refine your request or make a Freedom of Information Act request in future, please bear in mind that the Freedom of Information Act allows you to request recorded information held by us. You should identify the information that you want as clearly and concisely as you can, specifying the types of document that you are looking for. Although your request can take the form of a question, rather than a request for specific documents, we do not have to answer your question if it would require the creation of new information or the provision of a judgement, explanation, advice or opinion that was not already recorded at the time of your request.

Please see the attached information sheet for details of your right to appeal.

Yours sincerely

Sara Thomas

FOI Case Management Team

General Counsel

Transport for London

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