Haringey Heartlands Demolition and Site Preparation Works ......Haringey Heartlands Demolition and...

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Haringey Heartlands Demolition and Site Preparation Works ENVIRONMENTAL STATEMENT: NON-TECHNICAL SUMMARY 1 1. Introduction National Grid Property Holdings Limited (NGPH) and the Greater London Authority (GLA) (the ‘Applicant’) was granted by London Borough of Haringey (LBH) outline planning permission (Planning Application HGY/2009/0503) (hereafter referred to as the ‘2012 Planning Permission’) in March 2012 for the redevelopment of approximately 4.6 hectares of brownfield land known as ‘Clarendon Square. The 2012 Planning Permission relates to the following (hereafter referred to as the ‘Consented Development’): “Demolition of existing structures on the Site and the redevelopment to provide a residential led, mixed-use development, comprising between 950 to 1,080 residential units (Use Class C3); with 460sqm to 700sqm of office uses (Use Class B1); 370sqm to 700sqm of retail/financial and professional services uses (Use Class A1/A2); 190sqm to 550sqm of restaurant/café/drinking establishment uses (Use Class A3/A4); 325sqm to 550sqm of community/assembly/leisure uses (Use Class D1/D2); new landscaping, public and private open space, and energy centre, two utility compounds, up to 251 car parking spaces, cycle parking, access and other associated infrastructure works“. The Applicant is now seeking to obtain planning permission under Section 73 of the Town and Country Planning Act 1990 (hereafter referred to as S.73 Application). This will allow for the demolition of the existing structures on Site (excluding the Olympia Trading Estate); site preparation works (including remediation of soils); and the construction of two gas Pressure Reduction Stations (PRSs) (hereafter referred to as the ‘Site Preparation Works’) to be carried out in advance of the submission of any reserved matters application(s) for the Applicant’s wider redevelopment proposals for the Site, and discharge of ot her pre-commencement conditions associated with the 2012 Planning Permission. The development proposed in the S.73 Application is referred to as the ‘Proposed Development’. The S.73 Application would not alter the final built form, land use provision and quantum etc of the Applicant’s wider redevelopment proposals for the Site. Following consultation with LBH, the Applicant recognises that the Site Preparation Works would likely have the potential to give rise to significant effects on the environment. Accordingly an Environmental Impact Assessment (EIA) has been undertaken to assess the likely significant environmental effects of the Proposed Development. The EIA is reported in an Environmental Statement (ES), which has been prepared to accompany the planning application. The ES describes the methodologies used to carry out the EIA and sets out the likely significant environmental effects of the Proposed Development, taking account of a range of mitigation measures proposed to prevent, reduce or offset any adverse environmental effects of the Proposed Development. This document provides a summary of the ES findings in non-technical language.

Transcript of Haringey Heartlands Demolition and Site Preparation Works ......Haringey Heartlands Demolition and...

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1. Introduction

National Grid Property Holdings Limited (NGPH) and the Greater London Authority (GLA) (the ‘Applicant’) was

granted by London Borough of Haringey (LBH) outline planning permission (Planning Application

HGY/2009/0503) (hereafter referred to as the ‘2012 Planning Permission’) in March 2012 for the

redevelopment of approximately 4.6 hectares of brownfield land known as ‘Clarendon Square. The 2012

Planning Permission relates to the following (hereafter referred to as the ‘Consented Development’):

“Demolition of existing structures on the Site and the redevelopment to provide a residential led, mixed-use

development, comprising between 950 to 1,080 residential units (Use Class C3); with 460sqm to 700sqm of

office uses (Use Class B1); 370sqm to 700sqm of retail/financial and professional services uses (Use Class

A1/A2); 190sqm to 550sqm of restaurant/café/drinking establishment uses (Use Class A3/A4); 325sqm to

550sqm of community/assembly/leisure uses (Use Class D1/D2); new landscaping, public and private open

space, and energy centre, two utility compounds, up to 251 car parking spaces, cycle parking, access and

other associated infrastructure works“.

The Applicant is now seeking to obtain planning permission under Section 73 of the Town and Country

Planning Act 1990 (hereafter referred to as ‘S.73 Application’). This will allow for the demolition of the existing

structures on Site (excluding the Olympia Trading Estate); site preparation works (including remediation of

soils); and the construction of two gas Pressure Reduction Stations (PRSs) (hereafter referred to as the ‘Site

Preparation Works’) to be carried out in advance of the submission of any reserved matters application(s) for

the Applicant’s wider redevelopment proposals for the Site, and discharge of other pre-commencement

conditions associated with the 2012 Planning Permission.

The development proposed in the S.73 Application is referred to as the ‘Proposed Development’. The S.73

Application would not alter the final built form, land use provision and quantum etc of the Applicant’s wider

redevelopment proposals for the Site.

Following consultation with LBH, the Applicant recognises that the Site Preparation Works would likely have

the potential to give rise to significant effects on the environment. Accordingly an Environmental Impact

Assessment (EIA) has been undertaken to assess the likely significant environmental effects of the Proposed

Development. The EIA is reported in an Environmental Statement (ES), which has been prepared to

accompany the planning application. The ES describes the methodologies used to carry out the EIA and sets

out the likely significant environmental effects of the Proposed Development, taking account of a range of

mitigation measures proposed to prevent, reduce or offset any adverse environmental effects of the Proposed

Development.

This document provides a summary of the ES findings in non-technical language.

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Figure 1: Site Location

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Figure 2: Site Boundary of the Proposed Development

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2. EIA Methodology

EIA is a process which aims to ensure that the likely significant environmental effects of a Proposed

Development (which can be beneficial and / or adverse) are given due consideration in the determination of a

planning application. In accordance with the relevant legislative requirements and best practice guidelines, the

EIA was undertaken using established methods and criteria. This involved visits to the Site, along with

surveys, data reviews, consultation with a number of relevant statutory authorities, computer modelling and

specialist assessment undertaken by a team of qualified and experienced consultants.

The first stage of the EIA process involved undertaking a ‘Scoping Study’. The purpose of the study was to

identify the potentially significant environmental effects associated with the Proposed Development and

therefore the focus or scope of the ES. The Scoping Report which presented the findings of the Scoping

Study was submitted to LBH to support a request for their ‘Scoping Opinion’. A Scoping Opinion was received

from LBH in September 2013.

It was agreed with the LBH that the S.73 Application would need to include an assessment of the following

environmental topics:

Transportation and Access;

Noise and Vibration;

Air Quality;

Townscape and Visual;

Ground Conditions and Contamination;

Archaeology and Built Heritage;

Water Resources and Flood Risk;

Waste Management; and

Ecology.

In addition to the above, whilst LBH have confirmed that there are no relevant likely or reasonably foreseeable

schemes which should be considered cumulatively with the Proposed Development, the combination of

individual effects (for example dust, noise and visual effects) from the Proposed Development on a particular

receptor has been considered.

Each environmental assessment topic is reported in the ES as a ‘Technical Chapter’. Each Technical Chapter

describes how the assessment has been undertaken, the relevant environmental conditions on and adjacent

to the Site, and the potential likely significant effects of the Proposed Development. Each Technical Chapter

also describes a range of measures that would be incorporated to avoid, reduce, or offset any identified

adverse effects, and / or enhance potential beneficial effects. Such measures are referred to as ‘mitigation

measures’. The resulting effects (known as ‘residual effects’) following the implementation of mitigation are

also described.

3. Existing Land Uses and Activities

The Proposed Development is approximately centred on National Grid Reference 530840, 189870 and is

bound by: the B151: Mayes Road to the northeast; the B138L Hornsey Park Road to the east; the A504:

Turnpike Lane to the south; and the East Coast Mainline Railway to the west (hereafter referred to as the

‘Site’).

The Site is currently occupied by two gasholders located in the northeastern part of the Site; Mary Neuner

Road running north to south through the centre of the Site; the vacant Haringey Call Centre building in the

northern part of the Site; a car park and car compound operated by LBH in the north of the Site; and areas of

vacant hard standing and vegetation in the southern part of the Site.

Moselle Brook crosses the Site, in an underground channel, from west to east approximately mid-way through

the Site. A railway embankment forms the southwestern boundary of the Site, extending north up to the vacant

Haringey Call Centre building. An electrical sub-station is present on the eastern Site boundary.

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Figure 3: The Two gasholders viewed from Mary Neuner Road Figure 4: Electrical sub-station within the east of Site

The land uses and activities surrounding the Site are varied. Immediately to the north of the Site, along

Coburg Road, lie a number of four to five storey office buildings collectively known as ‘The Cultural Quarter’,

which accommodate commercial creative industries and the Mountview Theatre School. A Faith Miracle

Centre is located approximately 50m to the northwest of the Site on the junction of Coburg Road and Western

Road.

There are numerous two and three storey Victorian terraced houses located immediately adjacent to the

eastern boundary of the Site along Hornsey Park Road. Immediately to the south of the Site, along Clarendon

Road, there are seven two and three storey red brick buildings which accommodate a range of light industrial

and office units. Approximately 250m to the southeast, located on the junction of Turnpike Lane and Hornsey

High Street, is a modern six-storey residential development known as ‘Westpoint Apartments’ along with two

and three storey brick terrace buildings which contain small scale ground floor retail units with residential

above.

Immediately adjacent to the northeast corner of the Site, north of the northernmost gasholder, are a number of

low to medium rise light industrial units and adjacent to the northwest corner of the Site are a number of two

storey light industrial businesses. A major retail and residential complex known as ‘The Mall Wood Green

Shopping City’ and an associated multi-storey car park is situated approximately 250m northeast of the Site.

Only the lower two floors are occupied by retail stores, with the remaining floors occupied by residential uses.

Residential properties are located at the junction of Mayes Road and Brook Road, approximately 125m to the

northeast of the Site.

Wood Green Common, the closest green open space, lies approximately 400m to the north of the Site. Wood

Green Town Centre, including the Wood Green London Underground Limited (LUL) Station, is situated

approximately 600m northeast of the Site. Wood Green offers a range of retail, leisure and residential land

uses.

Other notable land uses in the vicinity of the Site include the East Coast Mainline Railway which runs

southeast to northwest immediately adjacent to the western boundary of the Site; the Hornsey Water Works

and associated filter beds and reservoir, approximately 200m west of the Site beyond the railway tracks; and

Alexandra Park and the Grade II listed Alexandra Palace situated approximately 600m and 900m northwest of

the Site respectively.

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4. Alternatives

In line with the EIA Regulations, the ES provides a description of the main alternatives to the Proposed

Development, considered by the Applicant and the projects demolition advisors. These include:

The ‘Do Nothing’ alternative;

Alternative Designs for the Demolition and Site Preparation Activities; and

Alternative Designs for the PRSs

The beneficial outcomes of leaving the Site in its current state would be minimal and the potential adverse

outcomes include: continued deterioration of the existing buildings and Site; continued increasing maintenance

costs of the small proportion of occupied and operational buildings on the Site; and the risk of the Consented

Development never being brought forward. By not bringing forward the Consented Development it would

mean that national, regional and local planning objectives would not be met; housing provision, employment

and other commercial opportunities would not be achieved; aspirations to improve pedestrian permeability to,

from and through the Site would not be achieved; Mary Neuner Road which runs through the Site would not

achieve its full purpose and potential; and significant opportunities to improve the quantum and quality of

public open spaces, together with the creation of Site vitality, a sense of place and community would be lost.

The demolition of the gasholders is a complex operation which would be undertaken by specialist contractors

and the preferred method of demolishing the gasholders has been identified by demolition advisors. Due to

the complexity of demolition process, an alternative demolition method is not considered appropriate and has

not been considered further.

Until demolition work has commenced, the method of remediation (e.g. stabilisation; solidification; and

bioremediation) cannot be determined. However, given that land has to be remediated prior to any future use

on the Site, no alternative has been considered.

The location and design of the PRSs are physically constrained by the provision of existing services across

the Site, along with the Applicant’s wider redevelopment proposals for the Site. As such, the details of the

PRSs remain as those presented in the Consented Development, and no alternatives have been considered

further.

5. The Proposed Development and Programme

The Site Preparation Works include the following activities, which may not necessarily be undertaken in the

following order:

Demolition of the gasholders and gasholder station;

Demolition of the vacant Haringey Call Centre;

Demolition of ancillary structures associated with the gasholders, gasholder station and call centre;

Remediation works;

Site surveys;

Site clearance;

Works of archaeological/ground investigation;

Erection of fencing or hoardings;

Provision of security measures or hoardings;

Erection of temporary buildings or structures associated with the Proposed Development;

Laying, removal or diversion of services;

Provision of construction compounds;

Removal of hard standing;

Construction of temporary access;

Provision of temporary highways access;

Provision of temporary internal estate roads;

Demolition of the PRS; and

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Construction of two PRSs

The Site Preparation Works are anticipated to commence in Quarter 1 2014 and be completed in Quarter 4

2015.

Due to the size of the Site, the ground remediation has been divided into two phases. The first phase would

take place within the south and west of the Site and would occur whilst the gasholders are demolished

(hereafter referred to as ‘Remediation Zone A’). Following demolition of the gasholders, the second phase of

remediation would take place within the north and east of the Site (hereafter referred to as ‘Remediation Zone

B’).

Figure 5 shows the structures within the Site which are to be demolished as part of the Proposed

Development.

Figure 5: Demolition and Remediation Zone Plan

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In order to control and manage the potential environmental effects associated with the Site Preparation Works,

a site-specific Environmental Management Plan (EMP) would be developed and implemented throughout the

duration of the works. This would specify a range of measures to manage the environmental effects that could

arise and would provide, for example, details of controls in relation to noise, vibration, and dust.

The EMP would be prepared in line with relevant legislative and best practice guidelines and would be agreed

with LBH. A Project Environmental Manager would implement the EMP and ensure that monitoring and

auditing is undertaken where this has been specified.

EMPs are an established method of managing environmental effects resulting from demolition works and they

are successfully adopted for other major schemes in urban areas.

6. Transportation and Access

The potential effects from the Proposed Development include short-term increases in vehicle movements from

construction vehicles associated with the Site Preparation Works on the existing highway network, including

the effects to pedestrian and cycle routes and the effects of the Site access on surrounding sensitive users. In

addition, the Proposed Development would generate some short-term employee trips from construction

workers.

The change in traffic volumes during the Site Preparation Works is predicted to be very low (less than a 2%

change) on the surrounding road network. Therefore, the Proposed Development would have little effect on

highway traffic. In addition, as the main effects on pedestrians would be from the additional vehicles on

pedestrian road crossing points, it is considered that the Proposed Development would result in a minimal

effect. The effect on cyclists would also be very limited as the intended vehicle routing as part of the Proposed

Development would not use any significant part of the local cycle routes.

The low change in traffic volumes from the Proposed Development would also result in a minimal effect on

Site Access and Servicing.

Whilst the Proposed Development is unlikely to cause any significant effects to transportation and access, in

accordance with best practice, a site-specific EMP would be implemented to closely control all vehicular

generations entering and leaving the Site during the Proposed Development.

A Transport Management Plan (TMP), which would detail the designated routes of vehicle movements

associated with the Proposed Development, would also be produced and submitted to the local planning

authority for approval prior to the commencement of works. This would be prepared in order to identify any key

area of potential conflict between vehicles and pedestrians/cyclists and would seek to make drivers aware of

any potential risks in regards to use of local cycle routes. This would ensure best practice in terms of

transportation management.

Overall, the transportation and access effects of the Proposed Development would not result in any significant

worsening of the operation of the local highway network and the Site access would not affect surrounding

sensitive users.

7. Noise and Vibration

The likely significant noise and vibration effects of the Proposed Development have been established in

accordance with published guidelines and best practice. The assessment included a review of comprehensive

baseline noise and vibration monitoring surveys undertaken in 2011 at the Site, together with the identification

of local receptors surrounding the Site which would be sensitive to noise and vibration (known as Noise

Sensitive Receptors (NSRs).

There are a number of NSRs within the vicinity of the Site. This includes residential properties on Hornsey

Park Road and at the junction of Mayes Road and Brook Road; users of the Faith Miracle Centre located at

the junction of Western Road and Coburg Road; users of Mountview Theatre School, immediately adjacent to

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the north of the Site; the commercial occupants of the creative industry units on Coburg Road to the north of

the Site; and users of Wood Green Common.

The Site Preparation Works would include activities that would be likely to increase noise levels and potentially

cause vibration. In particular, when activities are occurring closest to the Site boundary, this could result in

potential temporary increases of noise levels on surrounding streets and at NSRs. In addition, there would be

the potential for vibration generating activities to occasionally be perceptible to occupants of sensitive

receptors located within 10 to 15 metres of the Site boundary.

The implementation of noise and vibration control and management measures via the Site-specific EMP would

help to reduce noise and vibration disturbance to all sensitive receptors. The EMP would include measures

such as using low-noise machinery and equipment, enclosing and screening machinery, using low-vibratory

piling methods and the setting of, monitoring of, and adherence to specific noise and vibration threshold levels.

Given the small change (less than 2%) in vehicle trips on the highway network, there would be an insignificant

effect from noise and vibration from vehicles associated with the Proposed Development. In addition, there

would be no effect on Wood Green Common from the Proposed Development traffic noise.

Noise from the PRSs has the potential to effect existing and future NSRs. Suitable noise level limits, as

contained within the 2012 Planning Permission, have therefore been proposed to ensure that noise from the

operation of plant does not cause disturbance to both existing and future residents.

8. Air Quality

The Site Preparation Works could generate dust (referred to as demolition-derived nuisance dust) which could

cause a nuisance to surrounding sensitive uses (including residential dwellings and public parks). In addition,

emissions from plant such as excavators, bulldozers, concrete crushers and generators and from demolition

vehicles associated with the removal of waste materials could also have the potential to effect local air quality

conditions.

The air quality assessment for the likely demolition–derived nuisance dust effects from the Site Preparation

Works indicate that without mitigation, there would be the potential for short term negative effects at properties

between 10m and 200m from the Site. Due to the urban environment with built form acting as a screen, and

the distance dust in the air from demolition sites settles on the ground, the greatest effects are likely to occur

at sensitive uses between 10m and 100m from the Site. Consequently, it is considered that there would be no

effect beyond 200m from the Site.

The Site-specific EMP would include measures toreduce the creation of demolition-derived nuisance dust and

to mitigate dust created .

It is considered emissions from vehicles and plant associated with the Proposed Development would be

relatively small compared to local background air quality pollutant concentrations and existing traffic

movements. However, in order to mitigate any potential effects, routine environmental management

measures to control demolition traffic would be implemented. Measures would be discussed with LBH to

establish the most suitable access and haul routes for Site traffic, for example through a Site Traffic

Management Plan.

9. Townscape and Visual Effects

The townscape and visual effects assessment has assessed the likely significant effects of the Proposed

Development on the existing built environment and the general townscape. Consideration has been given to

the effects of the Proposed Development upon existing landscape features within the Site; the wider effects on

the landscape character of the Site and its surroundings; and the potential visual effects experienced by

receptors from representative viewpoints within and outside the boundary of the Site. .

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The Proposed Development has the potential to affect the townscape and visual quality of the Site and

surrounding environment, through changing the quality and value of parts of the identified Townscape

Character Areas and adding detractors to local views.

The implementation of good Site management, maintenance, and housekeeping would ensure that the

deterioration of townscape character and visual intrusion would be minimised, where possible. Since the use

of large scale plant such as tower or mobile cranes cannot be completely mitigated, some temporary, negative

and short term effects on townscape character would be inevitable during the Proposed Development.

The retention of the belt of mature lime trees on the Site boundary of Hornsey Park Road would mitigate

against any potentially significant adverse effects as a result of the construction of the PRS on Hornsey Park

Road. The PRS that would be located to the west of Mary Neuner Road would be in context to the other

industrial elements surrounding the Site and the existing railway line.

Visual effects from the Proposed Development would be limited owing to the dense intervening built form of

the Site and potentially sensitive visual receptors. Additional screening is provided by the dense vegetation

within the Grade II Registered Historic Park and Garden of Alexandra Palace and Park and the Register of

Public Parks, Gardens, Squares, Cemeteries and Churchyards of Local Historic Interest of Wood Green

Common.

10. Ground Conditions and Contamination

A desk-based assessment of the potential for ground contamination to exist at the Site was undertaken, based

on information obtained from historical maps, geological maps and previous Site Investigations (SI).

Previous SIs identified the presence of contamination within soil, surface water and groundwater. However,

the SI did not cover the entire Site as a result of access restrictions relating to the existing presence of the

current gasholders and the vacant Haringey Call Centre building on the Site. Further SI would therefore be

required once these structures are demolished and access is possible. In addition, the Applicant and project

demolition advisors have stated that the existing gasholder bases on the Site contain sludge.

The Proposed Development incorporates remedial works and the measures proposed include treatment or

removal of contaminated soils, water and sludge together with the creation of clean corridors for the proposed

new services. The final scope of the remedial works would be detailed within a Remediation Strategy that

would be prepared on completion of additional SI and submitted to LBH for approval.

All Site Preparation Works would be undertaken in accordance with legislative requirements and an EMP

would be implemented and followed, thereby minimising the risk of construction workers and the general

public being exposed to potentially contaminated soils, water, dust and ground gases.

The removal of existing hard-standing and the exposure of the soils to direct rainfall could potentially

temporarily result in the movement of contaminants into the Moselle Brook which crosses the Site within an

underground channel. However, a clay cut-off barrier would be installed to mitigate potential risks.

With standard mitigation measures and legislative controls in place, it is anticipated that there would not be

any significant effects due to ground conditions or contamination. Conversely, the Proposed Development

would remove exiting contamination from the Site. As such, the Proposed Development is likely to have

positive effects in relation to ground conditions and contamination at the Site.

11. Archaeology and Built Heritage

Archaeological potential at the Site is limited to remains pertaining to the Hornsey Gas Works, riverine alluvial

deposits formed along the former route of the Moselle Brook (prior to it being put in an underground channel)

and very limited potential for the survival of below ground heritage, in particular workers’ cottages associated

with the Welch’s Tobacco Company located to the north of the Site.

Site investigations of the underground channel of the Moselle Brook were carried out between 1997 and 2008

and no deposits of interest had been found. Consequently, alluvial deposits along the former route of the

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Moselle Brook could provide information of early pre-historic remains. However, investigations undertaken

between 1997 and 2008 did not record any alluvial deposits on the Site. It is considered that any potential

alluvial deposits are likely to have been impacted in the nineteenth and twentieth century relating to the

Hornsey Gas Works.

No structures on Site are designated and the gasholders have been assessed by English Heritage (EH) to be

undeserving of designation. However prior to any development, built heritage structures within the Site

(including the two surviving gasholders) would be recorded to a level and standard to be agreed with LBH and

EH. This is currently secured though a planning condition of the 2012 Planning Permission.

Given that the Site is located in proximity to three Archaeological Priority Areas, designated primarily due to

the known medieval activity in the vicinity, and the lack of evidence regarding the former course of the Moselle

Brook, a watching brief would be undertaken during groundworks in the area of the former Moselle Brook in

the east of the Site. This watching brief would also extend to the recording of any structures related to the

former operation of the Site, as well as the worker’s cottages previously located on the west of the Site.

12. Water Resources and Flood Risk

An assessment of the likely significant effects of the Proposed Development on surface water drainage,

groundwater flow and flood risk was carried out. This has been informed by topographical data for the Site, a

review of geological maps, borehole logs, groundwater maps and previous assessments for the Site. In

addition, the assessment has considered a Flood Risk Surface Water Briefing Note prepared by Waterman

Transport & Development for the Proposed Development. This Briefing Note has been based on the Flood

Risk Assessment (FRA) prepared in 2011 for the Consented Development.

As part of the Site Preparation Works, the removal of hardstanding; ground remediation; and dewatering of the

existing gasholders would have the potential to change existing surface water run-off. With the adoption of

best practice construction techniques it is considered that the risk would be low. To mitigate against potential

effects of overland flooding, an EMP would be implemented and existing surface water drainage flows and

connections maintained. All works would be subject to the relevant controls set out by the Environment

Agency and Thames Water.

Adequate protection would be given to the underground channel of the Moselle Brook during the

implementation of the Proposed Development in order to avoid structural damage and potential flooding. In

addition, works in proximity to the underground channel of the Moselle Brook would be subject to standard

best practice and mandatory regulatory controls. All works in proximity to the underground channel would be

undertaken in consultation and agreement with the EA and Thames Water. This would ensure that there

would be little or no overall risk posed by flooding from the Moselle Brook.

Removing the underground channel of the Moselle Bank is not a possibility for the Proposed Development.

This is because the existing channel is at a depth which would make the cross section of any open water

course deep and potentially hazardous in terms of safety. Furthermore, opening up the culvert, which runs

immediately to the west of the properties 123-151 Hornsey Park Road, may be problematic due to the

proximity to the rear gardens of existing residential properties. In addition, contamination from off-Site sources

would also be uncontrollable and would present an unquantifiable risk.

The Proposed Development would includ the laying, removal and diversion of existing services on Site.

However, no risk to groundwater flooding has been identified as the underlying aquifer is at least 30m below

ground level, and would not be affected by the realignment of existing services.

To prevent the risk of groundwater flooding during dewatering and infilling of the gasholders, dewatering would

be undertaken following consultation with the EA and carried out using standard techniques to be agreed with

the EA prior to any works being undertaken. As such no effect to groundwater flooding is predicted from the

Proposed Development.

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13. Ecology

A detailed desk study and a range of ecological surveys have been undertaken at the Site in July and

September 2013.

The potential ecological effects of the Proposed Development are largely confined to the area within the Site

itself. However, consideration has been given to the potential ecological effects which may spread beyond the

Site from the disturbance and disruption to species through lighting, dust, noise and vibration and changes to

water quality.

The closest statutory designated nature conservation sites, Railway Fields and Parkland Walk Local Nature

Reserve’s (LNR’s), both are located approximately 1.8km from the Site. Given the distance that separates the

two LNRs from the Site, it is considered there would not be any effects resulting from the Proposed

Development.

A number of non-statutory designated sites lie within the 500m of the Site, which include the New River (Sites

of Metropolitan Importance); Wood Green Reservoir (Sites of Borough Importance (SBI)); Alexandra Park

(SBI); Palace Gates (SBI); St Mary’s Churchyard (Sites of Local Importance). It is considered that indirect

effects of dust, noise and light pollution associated with the Site Preparation Works would likely give rise to a

temporary minor negative effect at these Sites within 500m. However, mitigation in the form of an EMP would

ensure that there would not be an effect on the non-statutory designated sites within 500m.

The Site consists of buildings and hard standing; species-poor semi-improved calcareous grassland; tall

ruderal vegetation; scrub; trees; amenity grassland and invasive species. These species are of value within

the boundary of the Site only. Given that the Proposed Development would remove all existing habitats on the

Site, there would be a short-term negative effect. However, there would be a beneficial effect from the

removal of butterfly bush and Japanese knotwood, which are both invasive species.

No evidence of roosting bats were recorded at the Site. However, the Site Preparation Works has the potential

to cause disturbance to bat species in habitats adjacent to the Site through indirect effects such as night time

lighting of the Site and dust from construction operators on adjacent habitats. Mitigation in the form of an EMP

would be implemented to control dust and night time noise and lighting of commuting and foraging routes for

bats adjacent to the Site.

The existing vegetation of the Site is considered to support common and local breeding bird species.

Consequently, the removal of vegetation and buildings would cause the loss of potential nesting, foraging and

perching opportunities for birds. Where possible Site Preparation Works would be undertaken outside of the

breeding bird season (i.e. undertaken between October – February inclusive). Where this is not possible,

check for any signs of nesting birds at buildings and within any vegetation would be undertaken by a suitably

qualified ecologist.

No evidence of reptiles was recorded at the Site as part of the surveys undertaken, and no effects from the

Proposed Development are anticipated.

The habitats on the Site provide opportunities for foraging and sheltering for common invertebrate species in

the form of scrub, trees and tall ruderal habitats. However, no protected invertebrate species were recorded

on the Site. Given that the Proposed Development would remove all existing habitats on the Site, in advance

of the submission of any reserved matters application, there would be a short-term negative effect on

invertebrates.

14. Waste Management

The Site Preparation Works associated with the Proposed Development have the potential to give rise to

significant volumes of waste material which would require appropriate handling and disposal to comply with

current legislation. As such, a qualitative assessment based upon the estimate of the amount of waste

generated by the Proposed Development, along with a review of the waste management practices to be

undertaken at the Site, has been undertaken.

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Haringey Heartlands Demolition and Site Preparation Works ENVIRONMENTAL STATEMENT: NON-TECHNICAL SUMMARY

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All waste materials removed from the Site would be carried out by a licensed contractor and all waste

materials would be disposed of at suitably licensed waste treatment and disposal facilities. At this stage, it is

not possible to identify which commercial waste treatment and disposal facilities would be used and therefore

an assessment of the potential effects of waste capacity at disposal and recycling facilities cannot be

completed. However, details on the facilities would be made available to LBH, as soon as an agreement is

made.

Waste management practices to be employed during the Proposed Development would be in line with the

relevant legislation and waste hierarchy. The implementation of a Site Waste Management Plan and the

Institution of Civil Engineers (ICE) Demolition Protocol would maximise the recycling and reuse of inert

demolition waste. However, given the quantity of waste material that would arise from the Site Preparation

Works, it is considered that there would be a short-term effect.

Any asbestos or other hazardous waste identified during the Proposed Development would be removed, and

disposed by specialist waste contractors in accordance with relevant legislation.

Given that the PRSs would be contained within pre-fabricated units, it is considered that the construction of

the two PRSs would not generate significant volumes of waste materials.

15. Cumulative Effects

Whilst LBH have confirmed that there are no relevant likely or reasonably foreseeable schemes which should

be considered cumulatively with the Proposed Development, the combination of individual effects (for example

dust, noise and visual effects) from the Proposed Development on a particular receptor has been considered..

During the Site Preparation Works, there would be some temporary combined effects of dust, noise, ecology

and townscape/visual/ heritage effects. However, the EMP would ameliorate these cumulative effects as far as

practically possible.

If you would like to receive further copies of this Non-Technical Summary or would like to purchase a copy of the Environmental Statement, please contact:

Waterman Energy, Environment & Design

Pickfords Wharf

Clink Street

London

SE1 9DG

Tel: 0207 928 7888

Email: [email protected]