Blackstone lane - contamination

Dear Mrs Oliver,

Thank you for your request for information below which has been given
reference FOI 4649. Please quote this on any correspondence regarding your
request.

Stockport Council will respond to your request within 20 working days. If
there will be a charge for disbursements e.g. photocopying in order to
provide the information, we will inform you as soon as possible to see if
you wish to proceed; however such charges are usually waived if they
amount to less than £10.

Yours sincerely,

Corporate Information Services

Stockport Metropolitan Borough Council

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Dear Mrs Oliver,

I am writing in response to your request for information (ref FOI 4649)
regarding Blackstone Lane.

The information has been prepared by the relevant Council service and is
as follows and attached.

‘why did the further testing done in June 2011 only comprise 12 window
sample boreholes which were not dug on a grid pattern as they should have
been?’

                                                             

The process of undertaking a site investigation should be carried out on a
phased approach, which builds upon previous investigations. 

Prior to the current phase of site investigation works commencing, the
scope of investigation works were discussed and agreed between the
Environmental Consultant undertaking the current investigation and the
Councils Contaminated Land Team.

In their professional opinion, the agreed locations of these 12 window
sample bore holes are the most appropriate to be carried out at this site.
They have been positioned to investigate specific geological features,
identified through the  previous site investigation undertaken at the
site in 2004, as well as locations which it was felt that there was
insufficient geotechnical information available to characterise  parts of
the site following the consultants review of the 2004 investigation data.

The location of these window sampling locations also permit the current
programme of landfill gas monitoring which is being undertaken within site
as well as outside the landfill site . The results of initial monitoring
have been communicated to you previously.

In addition to this current programme of ground gas monitoring, in the
near future to provide further assurance of the development and
remediation works to be undertaken at the site there will be an additional
programme of gas monitoring commencing surrounding the landfill site.

The site investigation conducted in 2004 was conducted in accordance with
industry best practice for conducting site investigations in accordance
with BS10175:2001 Investigation of Potentially Contaminated Sites – Code
of Practice.  The current phase of investigation works are being
undertaken and reported in accordance with  BS10175:2011 Investigation of
Potentially Contaminated Sites – Code of Practice. Landfill gas
monitoring results shall be reported and remediation works specified in
accordance with CIRIA 665 : Assessing risks posed by hazardous ground
gases to buildings.

‘Please let me see evidence that this matter has been discussed with the
Environment Agency and please let me have on this site and not by post
minutes of the meetings held to discuss this development to see what
consideration is being given to the contamination issue.’

There is no legal requirement for the Council to have discussions with the
Environment Agency at this stage. The Environment Agency may be consulted
at the planning stage if the planning application meets the consultation
criteria. The Council’s Environmental Health Department are the lead
regulator for this site and are satisfied that the appropriate
investigations are being undertaken at this time.

 

An Environmental Consultant has been appointed to investigate the ground
conditions of the site and to propose an appropriate remediation strategy
to enable the proposed development to take place. The Council has already
disclosed to you a copy of the previous report produced by the
consultant.  This phase 1 report shall be submitted to the to the
planning department upon validation of the development application.  In
addition to this the consultants shall be required to submit an intrusive
Phase 2 site investigation (which builds upon previous investigation
reports), a remediation proposal which would permit the safe development
of the site and a remediation validation report upon completion of
remediation works. 

We do not have any minutes of meetings that refer to contamination issues,
but minutes where the proposed development of the land was discussed at
the Neighbourhood Management Board are attached.

With regard to the supplementary question submitted.

“With regards to the contamination investigations, my independent expert
asked What a Window Sample Probehole is and what it is expected to
show.?”

    

It is well recognised by environmental professionals that different
investigation techniques are carried out using different methods according
to ground conditions. As your independent expert will be able to verify,
window sampling is an intrusive technique which uses a tracked hydraulic
rig which can be used to bore down to depths of around 6.00 to 8.00 metres
below ground level. 

The use of this sampling techniques allows a core sample of soil to be
removed from the borehole, soils can then be analysed from different
depths.  The excavated core of material can be tested for contaminants as
well as used for geotechnical purposes , e.g. for foundation design.

A probe hole is formed using a rotary drilling rig which is used to push 
drill rods into the ground until they meet resistance from the bedrock
below.  One use of a Probe hole, could be to locate former mine shafts, 
if a mine shaft was encountered the drilling rods would continue into the
ground without resistance into a mine shaft.  

I hope that this answers your query. However if you are unhappy with the
way we have handled your request you are entitled to ask for an internal
review. Any internal review will be carried out by a senior member of
staff who was not involved with your original request. To ask for an
internal review, contact [email address] in the first
instance.

If you are unhappy with the outcome of any internal review, you are
entitled to complain to the Information Commissioner. To do so, contact:

Information Commissioner’s Office

Wycliffe House

Water Lane

Wilmslow

Cheshire

SK9 5AF

www.ico.gov.uk

01625 545 745

Yours sincerely,

Corporate Information Services

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Dear Mrs Oliver,

 

Thank you for your request for information below which has been given
reference FOI 4777. Please quote this on any correspondence regarding your
request.

 

Stockport Council will respond to your request within 20 working days. If
there will be a charge for disbursements e.g. photocopying in order to
provide the information, we will inform you as soon as possible to see if
you wish to proceed; however such charges are usually waived if they
amount to less than £10.

 

Yours sincerely,

 

 

Corporate Information Services

Stockport Metropolitan Borough Council

 

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Dear Mrs Oliver,

 

Thank you for your request for information below which has been given
reference FOI 4778. Please quote this on any correspondence regarding your
request.

 

Stockport Council will respond to your request within 20 working days. If
there will be a charge for disbursements e.g. photocopying in order to
provide the information, we will inform you as soon as possible to see if
you wish to proceed; however such charges are usually waived if they
amount to less than £10.

 

Yours sincerely,

 

 

Corporate Information Services

Stockport Metropolitan Borough Council

 

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Dear Mrs Oliver,

 

I am writing in response to your request for information below (Ref 4778).

The response to your request has been prepared by the relevant Council
service and is as follows:

 

No minutes of these meetings are taken; however please find attached the
meeting agendas.

 

If you are unhappy with the way we have handled your request you are
entitled to ask for an internal review. Any internal review will be
carried out by a senior member of staff who was not involved with your
original request. To ask for an internal review, contact
[1][email address] in the first instance.

 

If you are unhappy with the outcome of any internal review, you are
entitled to complain to the Information Commissioner. To do so, contact:

 

Information Commissioner’s Office

Wycliffe House

Water Lane

Wilmslow

Cheshire

SK9 5AF

 

[2]www.ico.gov.uk

 

01625 545 745

 

Yours sincerely,

 

Corporate Information Services

Stockport Metropolitan Borough Council

 

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Dear Mrs Oliver,

 

I am writing in response to your request for information below (Ref 4777).

 

The response to your request has been prepared by the relevant Council
services and is as follows:

 

Depending upon the nature of, and source of contamination, Section 7 of BS
10175: 2011 recommends employing a mixture of a) targeted sampling, which
focuses on known, suspected or point source areas of contamination, and;
b) non-targeted sampling, which characterises the contamination status of
a defined area or volume of a site or zone.

 

The standard recommends the use of non-targeted sampling be employed
through the main sampling strategy.  This method may employ a regular
sampling grid pattern.  Subsequent intrusive investigations may employ
targeted sampling to delineate or confirm an area of contamination
detected.

 

As previously stated the current investigation is built upon previous
intrusive site investigations, these have included the employment of a
non-targeted sampling distribution.  The distribution of recent sampling
has employed targeted sampling in order to further delineate the extent of
contamination and specific geotechnical features.    

 

Point 5.2.4 of BS10175 – Consultation with regulars, recommends that the
“relevant regulatory authorities should be consulted and involved in the
developing the investigation strategy”.  As previously stated the
Council’s Environmental Health Department are the lead regulator for this
site and have been involved in the development of supplementary site
investigation works. The Environment Agency may be consulted at the
planning stage if the planning application meets the consultation
criteria.

 

The Council has previously given you the notes of the meetings with the
Developer which the Council holds – please see answer to your FOI requests
with references FOI 4391 and FOI 4649.

 

The Council has done financial checks on the developer and the guarantor.
The Scrutiny Committee acknowledged that  “THi Riverside was a fairly new
company but were satisfied that the imposition of a financial guarantor
(GB Solutions) to underwrite all of the obligations of THi Riverside would
mitigate this risk”.  

 

The Executive report considered that £0.6m should be considered to deal
with remediation issues on the Blackstone Fields site on top of the usual
construction costs to allow the development to be built. However on top of
this figure, an additional amount will be needed to allow for the
additional costs of foundation, piling etc. for putting buildings on this
particular site. Currently this additional cost is estimated to be between
£0.3m to £0.5m but these figures are subject to change, once further
investigatory works are undertaken. For the Dialstone site, the House
builder will have made an estimate of how much is needed for remediation
of that site but the Council does not hold this information.

 

If you are unhappy with the way we have handled your request for
information, you are entitled to ask for an internal review; however you
must do so within 40 working days of the date of this response. Any
internal review will be carried out by a senior member of staff who was
not involved with your original request. To ask for an internal review,
contact [1][email address] in the first instance.

 

If you are unhappy with the outcome of any internal review, you are
entitled to complain to the Information Commissioner. To do so, contact:

 

Information Commissioner’s Office

Wycliffe House

Water Lane

Wilmslow

Cheshire

SK9 5AF

 

[2]www.ico.gov.uk

 

01625 545 745

 

Yours sincerely,

 

Corporate Information Services

Stockport Metropolitan Borough Council

 

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