Waverley Borough Council Committee System - Committee Document
Meeting of the Executive held on 20/09/2004
Summary & Purpose
At a meeting on 12th July 2004, the Executive received a presentation on matters relating to the Godalming Key Site from the development team. Following this, members were minded to look sympathetically at the proposal from the developers for Phase 1 of the scheme, subject to the officers being instructed to submit a detailed report to the Executive on options available to secure remediation of the site and the implications for Waverley arising from the Key Site.
This report aims to provide Members with the information on the proposals for Phase 1 and the options available to secure remediation of Phase 2.
Quality of Life Implications
Prevention and Control
A large part of the site known as Godalming Key Site was formerly used as a gas works. There does not appear to have been any substantial remediation works since the closure of the gas works other than the removal of the gas holders and ancillary structures. Gas works sites are generally heavily contaminated and the contaminants may well leach into the surrounding area. The contaminants present at a gas works site are directly related to gas manufacture process. It seems likely that the principal structures of the gas works were in different locations during its operating period and consequently the contamination could be widespread across the site, with areas of more heavily contaminated ground likely to be in the vicinity of the main structures.
The development of the Key Site will ensure the remediation of the land and therefore remove the risk to the local environment.
There are no e-government implications.
Resource and legal implications
Waverley received a premium of £1.5m on the disposal of the site of Phase 1 (the former depot and car park). Under the terms of the contract, Waverley could potentially be entitled to a share of profit after a certain level is achieved. The proposals referred to in this report may affect whether or not that level of profit is reached, and the amount (if any) receivable by Waverley.
In addition, Waverley is contractually entitled to a small share of potential profits from the development of the remainder of the Key Site. This is further detailed in the (Exempt) report, together with a risk analysis.
Waverley has no ownership of the remainder of the Key Site and the developer is still in the process of acquiring all other ownerships. Members should refer to the (Exempt) Appendix for the full financial details arising from the site.
1. In July 2000, Roger Evans and Associates were commissioned by the Council to prepare a development framework for the Godalming “Key Site”, as identified in the Replacement Local Plan. The aim was to set out a coherent approach on design and access issues to encourage and guide proposals for redevelopment within the Key Site.
2. The main objectives for the site are to improve the townscape and to retain and secure a mixture of uses, which support and complement the well-being of the town and its centre. It was recognised that while the site was in a number of separate ownerships, the piecemeal development of each of them might not realise the location’s total design potential. Therefore, the Council sought a co-ordinated development of the Key Site.
3. It is known that the western part of the site contains up to 3 metres of made-up ground and the redundant underground structures related to the former gas works remains on the site. Past investigations have indicated the presence in the soil of pollutants typically related to this activity. Other pollutants have been identified in the groundwater of the site. It is understood that remediation could be achieved by the removal of the worst areas and providing an impervious barrier in areas to be landscaped.
4. Planning permission was granted in April 2003 to Belvedere Smith Properties (Key Site) LLP for the development of the Council’s former depot site (Phase 1). As a condition of planning and prior to the commencement of the development, a contamination survey was to be carried out and a remediation scheme proposed for the site. Connell Mott MacDonald carried out two surveys, a preliminary investigation in May 2003 and a main investigation in October 2003.
5. Following chemical analysis, the most appropriate remediation of the site is to provide a secant pile wall installation around the basement and proposed central landscaping area, excavation to remove significant contamination sources and in the soft landscaped areas to install a cover system, which includes an impervious barrier.
6. The purpose of the secant pile wall is to mitigate the amount of contaminated ground water being drawn out during the de-watering of the basement excavation. It was originally intended that steel sheet piling would be used but due to the lateral water pressure in the ground the sheet piles may rotate or be otherwise insufficient. The installation of the secant pile wall has resulted in additional costs.
7. Members will remember that at the Executive on 12th July 2004, the developers outlined their proposal for an additional floor to Phase 1 in order to recover the additional costs incurred due to the levels of contamination and to provide the necessary cash flow to meet their contractual retentions.
8. The cost of the secant piling, together with other additional costs will have affected potential profit for Phase 1. The financial commitment to the scheme as it currently stands means that a cash deficit could be carried through to Phase 2. Details are included in (
Exempt) Appendix B – to follow
9. As previously stated, it has always been the Council’s intention to seek a co-ordinated development of the Key Site. In order to ensure that the developer continues with the rest of the Key Site development and does not "walk away" after the completion of Phase 1, should he be successful with the planning application for the additional floor, the Council needs to look at ways to ensure remediation of the remainder of the site. Details are included in the (Exempt) Appendix.
10. Under the terms of the existing contract a sum of money (referred to in the (Exempt) Appendix) is already held by Waverley on deposit against the developer failing to proceed with the remainder of the Key Site. Should the developer not comply with his obligations under the existing contract, Waverley will become entitled to this sum unconditionally.
11. An alternative solution is set out in the (Exempt) Appendix.
12. An analysis of the risks for the Council is included in the (Exempt) report. However, failure to proceed as planned would result in a non-cohesive development and considerable delay before the site is remediated.
Link to Phase 2
13. The height of the new proposed scheme with an additional floor is no higher than the ridge level of the existing scheme. The proposed scheme now has a flat roof rather than a pitched one. The revised elevation provides the necessary link with the outline proposals for the rest of the Key Site development.
14. Due to the anticipated levels of contamination to the remainder of the site (Phase 2) and consequent remediation costs, it is necessary to maximise the development to the remainder of the site. The revision to Phase 1 provides a similar approach to the remainder of the proposed development.
15. From historical contamination survey data for the remainder of the site and from the findings of the surveys for Phase 1 it has been possible to surmise the likely levels of contamination to Phase 2. As Phase 2 will comprise the redevelopment of the areas of gas manufacture and other associated processes, it is likely these areas will be the most contaminated, particularly from previous experience of gas site remediation. It is anticipated that heavily contaminated ground will be encountered with higher concentrations of contaminants than found during Phase 1 works.
16. Phase 1 proved to be more contaminated than anticipated and therefore it is probable that there are areas of heavily contaminated ground within Phase 2 of the Key Site which will require a substantial amount of remediation at significant cost.
17. Black and Veatch Consulting were commissioned by Belvedere Smith Properties (Key Site) LLP in May 2004 to identify possible measures for dealing with soil and groundwater that are expected to be heavily contaminated in some areas of the site. Until full site investigations are carried out, the remedial options are based on current understanding of the site and are therefore only provisional.
18. Three scenarios have been drawn for the site and remedial options proposed:-
l. It is assumed that the range of contaminants present is limited and that the degree of contamination in the soil and groundwater is not as high as anticipated from a preliminary review of available site information.
The remediation of the site will involve the excavation of a relatively small volume of contaminated soil and given that the leaching potential of any remaining contaminated soil is low, it is anticipated no additional remedial works will be required. The estimated cost is referred to in the (Exempt) report.
ll. It is assumed that the range of contaminants and the degree of contamination in the soil and groundwater is similar to that encountered during Phase 1 of the development. The excavation of the basement and the general site works will involve the removal of a significant volume of contaminated ground and so there will be a reduction in the source of the contamination. It is anticipated however that a considerable volume of contaminated material will remain and that that contaminated material will have the potential to leach into the groundwater. It is envisaged that the most heavily contaminated sections of the site will need to be isolated from the ground water with an underground impermeable barrier such as a continuous secant pile wall. The estimated cost of the remedial works is referred to in the (Exempt) report.
lll. It is assumed that the site is heavily contaminated and that additional leaks and spillages from the industrial use since the closure of the gas works have increased the type and concentration of the contaminants present in the soil and groundwater. In order to remediate the site it is anticipated that the excavation of the basement and general site works will involve the removal of a significant volume of the contaminated ground and so there will be a reduction in the source of contamination. Tanks and pipes will be emptied and removed from site but it is anticipated that a considerable volume of contaminated material will remain on site and that these will continue to leach contaminants into the groundwater. It may be necessary to install a permeable reactive barrier to maintain the free flow of groundwater. The estimated cost of the works is referred to in the (Exempt) report.
19. It is anticipated that the contamination levels on the site will be high and the cost of remediation is referred to in the (Exempt) report.
The Executive is asked to consider the information and advice in the (Exempt) report and make a recommendation to Council.
There are no background papers (as defined by Section 100D(5) of the Local Government Act 1972) relating to this report.
Mr M Stevenson
: 01483 523455
Mrs J Turner 01483 523468