McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
REP/004/21
Issue | 16 April 2021
This report takes into account the particular instructions and requirements of our client. It is not intended for and should not be relied upon by any third party and no responsibility is undertaken to any third party.
Job number 602709-00
Ove Arup & Partners Ltd 63 St Thomas Street Bristol BS1 6JZ United Kingdom www.arup.com
Document verification
Job title Old Brewery, Ashton Job number 602709-00 Document title Remediation Implementation and Verification Plan File reference
Document ref REP/004/21 Revision Date Filename 2021 -04-08_RIVP_BristolBrewery.docx Draft 1 25 Mar Description First draft 2021
Prepared by Checked by Approved by Agnieszka Name Jacob Mennell Lopez-Parodi Signature P1.0 9 Apr Filename 2021 -04-09_RIVP_BristolBrewery_ISSUE.docx 2021 Description For Issue
Prepared by Checked by Approved by Agnieszka Name Jacob Mennell Tarek Sadek Lopez-Parodi Signature Issue 16 April Filename 2021 -04-16_RIVP_BristolBrewery_ISSUE.docx 2021 Description Revised following external comments
Prepared by Checked by Approved by Agnieszka Name Jacob Mennell Tarek Sadek Lopez-Parodi
Signature
Filename Description
Prepared by Checked by Approved by Name
Signature
Issue Document verification with document ✓
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Contents
Page
1 Introduction 1 1.1 Limitations 1 1.2 Proposed development 1 1.3 Planning conditions 2
2 Site Information 4 2.1 Site location and description 4 2.2 Site history 4 2.3 Radon 4 2.4 Unexploded ordnance 5 2.5 Completed assessments and investigations 5
3 Site conditions 6 3.1 Ground and groundwater conditions 6 3.2 Visual and olfactory evidence of contamination 7 3.3 Summary of previous assessments 7
4 Revised Conceptual Site Model 10 4.1 Sources 10 4.2 Pathways 11 4.3 Receptors 12 4.4 Summary 12 4.5 Relevant pollutant linkages 16
5 Revised Risk Assessment 18 5.1 Human health 18 5.2 Ground gas 22 5.3 Summary of revised risk assessment 22
6 Remediation Objectives and Strategy 23 6.1 Site wide non RPL specific 23 6.2 RPL specific 26
7 Verification plan 31 7.1 Non RPL specific 31 7.2 RPL specific 33
8 Materials Verification 36 8.1 Excavation validation methodology 36 8.2 Materials verification criteria 36
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
8.3 Soil sample collection 39
Appendices
Appendix A Development Proposals
Appendix B BGS Radon Report
Appendix C Tier 1 Soil Assessment
Appendix D Arup GAC Derivation
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
1 Introduction
Ove Arup & Partners Ltd (Arup) have been appointed on behalf of McLaughlin & Harvey to provide multidisciplinary engineering services for the development of a multi-storey, mixed-use office and residential complex in central Bristol. Hydrock Consultants Limited (Hydrock) were commissioned by Change Real Estate to undertake a Ground Investigation and Interpretative Report for the site [1] [2]. This report should be read in conjunction with earlier reports produced by Hydrock. Hydrock investigations and assessments indicated that relevant pollutant linkages exist onsite which would require mitigation as part of the proposed development. Development proposals have since evolved, and therefore, where appropriate, Hydrock’s assessments and recommendations have been reviewed and revised. As such, the following Remediation Implementation and Verification Plan (RIVP) has been prepared. The Verification Plan aspect of this report provides guidance to the contractor on how to compile the Verification Report and what information needs to be collated during the proposed works. Measures to adequately manage unexpected contamination are also provided in this report.
1.1 Limitations This report has been prepared for the use by McLaughlin & Harvey and takes into consideration their particular instructions and requirements. It is not intended for, and should not be relied upon by, any third party and no responsibility is undertaken to any third party.
1.2 Proposed development The proposed development is to comprise commercial and residential accommodation, involving the extension and refurbishment of existing buildings and new structures. The development layout has been revised since the Hydrock reports were produced and includes: • Commercial 1-2 storey buildings to the north of the site, with courtyards between buildings covered in hardstanding with plants in planters; • Residential apartment block in the central east of the site; between 3-8 storeys with a first floor residential garden (hardstanding and planters) and ground floor car park, plant rooms and storage; and • Two residential two storey townhouses to the south-west, separated from the central site by Baynton Road. Patio and hardstanding are to cover the open space around the houses; these properties will be managed by the developer. A proposed development plan is included as Appendix A.
REP/004/21 | Issue | 16 April 2021 Page 1 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
1.3 Planning conditions The following report has been prepared to support discharge of pre- commencement conditions for planning permission 18/04367/F. The Hydrock Desk Study and GIR were produced in accordance with condition three sub parts i) and ii) of the below condition: 3) Land affected by contamination - Site Characterisation No development shall take place until an investigation and risk assessment, in addition to any assessment provided with the planning application, and has been completed in accordance with a scheme to assess the nature and extent of any contamination on the site, whether or not it originates on the site. The contents of the scheme should be submitted to and be approved in writing by the Local Planning Authority. The investigation and risk assessment must be undertaken by competent persons and a written report of the findings must be produced. The written report is subject to the approval in writing of the Local Planning Authority. The report of the findings must include: (i) a survey of the extent, scale and nature of contamination; (ii) (an assessment of the potential risks to: a. human health b. property (existing or proposed) including buildings, crops, livestock, pets, woodland and service lines and pipes c. adjoining land d. groundwaters and surface waters, e. ecological systems f. archaeological sites and antient monuments (iii) an appraisal of remedial options, and proposal of the preferred option(s). The following report has been prepared in support of condition three sub part iii). It should be noted that Section 2 and Section 3 of this report provide a summary of the Hydrock findings for clarity. Sections 4 and Section 5 provide a review of Hydrock findings and present a revised risk assessment in light of the Arup review. The assessments in this report should be seen to supersede the assessments presented in the Hydrock GIR. Further to the above, the report is looking to inform the discharge of Condition 4: 4) Land affected by contamination – Submission of Remediation Scheme No development shall take place until a detailed remediation scheme to bring the site to a condition suitable for the intended use by removing unacceptable risks to human health, buildings and other property and the natural and historical environment has been prepared, submitted to and been approved in writing by the Local Planning Authority. The scheme
REP/004/21 | Issue | 16 April 2021 Page 2 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
must include all works to be undertaken, proposed remediation objectives and remediation criteria, timetable of works and site management procedures. The scheme must ensure that the site will not qualify as contaminated land under Part 2A of the Environmental Protection Act 1990 in relation to the intended use of the land after remediation. Finally, the report provides recommendations should land affected by contamination be encountered, including a course of action to verify the success of any remediation measures. This supports the discharge of the below condition: 5) Land affected by contamination - Implementation of Approved Remediation Scheme In the event that contamination is found, no development other than that required to be carried out as part of an approved scheme of remediation shall take place until the approved remediation scheme has been carried out in accordance with its terms. The Local Planning Authority must be given two weeks written notification of commencement of the remediation scheme works. Following completion of measures identified in the approved remediation scheme, a verification report that demonstrates the effectiveness of the remediation carried out must be produced, and approved in writing of the Local Planning Authority.
REP/004/21 | Issue | 16 April 2021 Page 3 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
2 Site Information
2.1 Site location and description The site is centred at National Grid Reference 357220E, 171710N. The nearest post code is BS3 2EB. The site covers an area of approximately 1.2 ha and currently comprises several industrial units including a printing studio, storage warehouses, car dealership and vehicle repair garages. The entire site is currently covered by hardstanding.
2.2 Site history A review of Ordnance Survey and Bristol City Council mapping suggest that site development began pre 1844. This was likely post 1828 as mapping indicates farmlands to the north and east of the site during this time [3]. Several historic land uses have been identified within the site boundary including, engineering works, residential, bottling works, dairy, warehouses, depot and brewery. The brewery was present to the north - north-east of the site and it is thought that several of the existing onsite buildings pertain to its existence. Currently, site land use includes a printing studio, storage warehouses, car dealership and vehicle repair garages. Historical mapping indicates the presence of a large pond, orientated north-east – south-west in the southern portion of the site. This appears to have been infilled prior to 1903. Off site land uses include residential development, largely to the east and south, and a park to the north. Industrial development has occurred locally to the north and south-west.
2.3 Radon The Hydrock GIR [2] indicates that the site is situated within a Radon Affected Area with 3-5% of properties above the action level. An additional Radon Report has been obtained from the British Geological Survey (refer to Appendix B). The report indicates that the vast majority of the southern, central, and western site are within an area of 3-5% of properties at or above the action level. However, the northern site is shown to be in an area of 0-1% of properties estimated to be at or above the action level. However, due to the data resolution it is difficult to delineate a distinct radon boundary on site. Therefore, it is recommended that basic protection measures are included within the design and construction of buildings/extensions within the site. The Hydrock GIR states that, subject to a detailed design, radon protection measures may afford mitigation of any residual risk from ground gas. This is not necessarily the case, as stated in BS B485: ‘no assumptions can be made about measures installed to protect against radon being also protective against methane and carbon dioxide even when properly installed and verified’. The requirements for a gas resistant membrane are not necessarily suitable for radon protection
REP/004/21 | Issue | 16 April 2021 Page 4 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
measures. Further discussion on ground gas is included in Section 3.3.3 and Section 5.2
2.4 Unexploded ordnance Hydrock identified the site to be in an area with high unexploded ordnance (UXO) risk and therefore commissioned EOD Contracts Limited to conduct a specialist UXO desktop study [4]. The completed study indicated the risk posed by UXO to be low. It was recommended for UXO safety awareness training to be given to site personnel of all levels, alongside, selected individuals working on the project with relevant responsibilities. The awareness training should be delivered as part of the project safety induction by a competent individual. It was stated that this should be reinforced with specific safety briefings and toolbox talks to persons involved in intrusive earthworks.
2.5 Completed assessments and investigations Hydrock completed a Desk Study, which identified plausible pollutant linkages that required further assessment through an intrusive investigation [1]. Hydrock subsequently designed a ground investigation that was undertaken in January 2018 and comprised the following: • 8 dynamic sampled/ rotary cored boreholes to a maximum depth of 25.20m bgl; • 16 hand dug trial pits to a maximum depth of 1.77m bgl; • chemical testing of soil, water and soil leachate samples, and geotechnical testing of soils and rocks; • 8 installations in boreholes for ground gas and groundwater monitoring; • 1 falling head permeability test in BH04; and • 3 gas and groundwater monitoring rounds. In March 2018 an interpretive report based on the findings of the investigation was produced. The following reports have been provided to Arup: • Hydrock Consultants Limited. March 2017. The Old Brewery, Southville, Ground Conditions Desk Study, reference OBS-HYD-XX-GI-RP-G-1001-P1 [1]; • Hydrock Consultants Limited. March 2018. The Old Brewery, Southville, Ground Investigation Interpretative Report, reference OBS-HYD-XX-GI-RP- G-1002-P1 [2];
REP/004/21 | Issue | 16 April 2021 Page 5 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
3 Site conditions
The findings of the Hydrock ground investigation are presented in full in the Hydrock Ground Investigation Report [2]. The following section provides a summary of the pertinent findings.
3.1 Ground and groundwater conditions The ground conditions encountered at the site have been summarised in Table 1 below.
Table 1: Generalised stratigraphy
Stratum Descriptions Depth to Thickness top (m range (m) bgl) Made Ground Slightly sandy, silty angular to sub- 0 0.36 to 2.7 angular fine to medium sand or fine to coarse gravel of brick, ceramics, asphalt, occasional metal fragments, clinker, slate, ashy sand, concrete, red sandstone, siliceous and igneous material. River Terrace Deposits Soft light bluish grey/grey/brown locally 0.36 to 2.7 1.4 to 4.75 / Alluvium *1 mottled orangish brown, silty, sandy, CLAY with a slight organic odour and rare partially decomposed organic material and occasional layers of very soft dark brown pseudo-fibrous peat. Mercia Mudstone Firm reddish brown, slightly sandy, silty, 4 to 5.3 2.15 to 3.9 Formation CLAY becoming very stiff with depth and with layers of fine to medium sand. Very weak, locally weak, becoming 7.2 to 9.2 5.65 to 7.2 weak with depth, reddish brown, locally mottled, greenish grey, MUDSTONE locally tending to fine sandstone. Weak, locally very weak reddish-brown, 13 to 14.4 3.35 to 4.3 fine SANDSTONE. Weak, locally very weak, reddish-brown, 17.3 to Unknown fine SANDSTONE, 17.65 interbedded with weak, reddish-brown, CONGLOMERATE and MUDSTONE. Note: *1 No distinctive river deposits encountered based on description likely alluvium.
Groundwater was encountered as strikes during the investigation between 1.6 and 2.9m bgl within the alluvium. Groundwater was encountered at 1.6m bgl within the made ground at the location of the infilled pond, owing to an increased thickness of made ground in this area likely resulting from the historic filling of the pond. The material infilling the pond does not appear different from made ground underlying the wider site, indicating the pond was backfilled as part of a wider site development.
REP/004/21 | Issue | 16 April 2021 Page 6 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
A singular trial pit encountered groundwater at 0.46m bgl suggesting there may be discontinuous perched groundwater present within the made ground. Post works monitoring found groundwater level to very between 7.32 and 5.33m AOD across the site (circa 0.5 to 1.8m bgl).
3.2 Visual and olfactory evidence of contamination The Hydrock investigation identified visual and olfactory evidence of contamination within the made ground and alluvium strata, documenting the existence of asbestos sheeting, hydrocarbon odour, strong hydrocarbon odour, oily sheen and common man-made constituents within the made ground, as detailed in Section 3.1. Table 2: Visual and olfactory evidence of contamination
Location Evidence Depth (m bgl) Stratum Groundwater (m bgl) TP06 Asbestos sheeting 0.7 Made Ground No data TP10A Hydrocarbon odour 1.6 Made Ground No data and oily sheen BH01A Hydrocarbon odour 1.2-1.65 Alluvium 1.73-1.80 BH06 Strong hydrocarbon 1.4-1.7 Made Ground 0.81-1.26 odour BH06 Hydrocarbon odour 1.7-2.2 Alluvium 0.81-1.26
3.3 Summary of previous assessments The Hydrock geo-environmental assessment concluded that contamination existed within the made ground, with elevated lead, PAH, localised petroleum hydrocarbons and asbestos at two locations. It was concluded that this had the potential to impact human health, and therefore, a series of mitigation measures were recommended. The results of the Hydrock assessments are presented in the following section. Revised assessments have been undertaken by Arup where deemed necessary and included in Section 5 of this report.
3.3.1 Human health Hydrock completed a human health risk assessment on the basis that the development included a mixture of public open space, commercial and residential accommodation. The assessment used their in-house derived soil screening values for the ‘residential without plant uptake’ (RWPU) and ‘public open space’ (POS) land uses. Hydrock undertook statistical analysis on the made ground assuming a single averaging area, the results are summarised below:
• US95 exceedances of the RWPU criteria were identified for lead, benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, chrysene, dibenz(a,h)anthracene, and indeno(1,2,3,cd)pyrene.
REP/004/21 | Issue | 16 April 2021 Page 7 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
• US95 exceedances of the POS criteria were identified for benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene and dibenz(a,h)anthracene Elevated petroleum hydrocarbons were identified to the west and north of the site (BH06 and TP10A respectively). These did not exceed the POS criteria, however they did exceed the residential end use without plant uptake criteria. Asbestos was identified within the made ground in 4No. samples. These samples were taken from the centre of the site and western boundary (BH03 and TP06 respectively). Overall, the analysis found the made ground at the site unsuitable for residential without plant up take end use. The alluvium did not indicate any exceedances of the assessment criteria for either RWPU or POS.
3.3.2 Controlled waters Hydrock undertook a controlled waters risk assessment in accordance with the Environment Agency Remedial Targets Methodology [5], which provides a tiered approach towards risk assessment. Leachate and groundwater samples were screened against Water Quality Targets (WQT). The primary water body receptors were identified as the underlying Secondary A aquifer and River Avon circa 300m to the north. The aquatic ecosystem was identified as a secondary receptor. The WQT were selected with respect to human health (based on Drinking Water Standards) and for protecting aquatic ecosystems (Environmental Quality Standards). Elevated levels of leachable metals and PAH compounds were identified in the made ground. However, no PAH compounds were detected within the groundwater. In addition, Hydrock completed a review of the geochemical atlas of England and Wales. It was concluded that elevated metals in groundwater are likely to have originated from natural soils and therefore were considered not to pose a significant pollution risk to controlled waters. In summary, no measurable impact to controlled waters was identified by Hydrock’s assessment. Although, no petroleum hydrocarbons were measured above detectable concentrations in the groundwater, the report does identify the potential risk of groundwater contamination from petroleum hydrocarbons in the soils and therefore recommended that mitigation measures should be adopted but provided no specific details.
3.3.3 Ground gas Hydrock undertook a ground gas risk assessment in accordance with BS 8485:2015, CIRIA Report 665 [6] and NHBC [7]. Hydrock undertook three ground gas monitoring visits at times of relatively high atmospheric pressure (1015hPa – 1027hPa). Results indicated no methane and maximum CO2 levels of 4.9%v/v. Flow rates of between 0.3 and 0.7l/hr were recorded. Hydrock assessed the site to be within the Characteristic Situation 1
REP/004/21 | Issue | 16 April 2021 Page 8 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
(CS1 - very low hazard potential). It was determined that there is a low risk from ground gas subject to additional monitoring. Hydrock recommended that to be compliant with CIRIA Report 665, three additional monitoring visits would have to be undertaken. Failing this, design should account for the anticipated worst-case scenario conditions, however it was not stated what that scenario would entail. The assessment recommends gas protection measures to mitigate against nuisance odours generated from hydrocarbon and VOC contamination. The Hydrock assessment details an exceedance of carbon dioxide in soil under the HSE Workplace Exposure Limits at 1.5% for short term (15-minute exposure) and 0.5% for long term exposure. It was recommended that contractors and maintenance workers take all necessary health and safety precautions when working in enclosed spaces.
3.3.4 Plant life risk assessment The Hydrock assessment screened priority phytotoxic chemical concentrations against published values to determine risk to plant growth. Within made ground, statistical testing was utilised to assess concentrations relative to the US95.
Elevated concentrations of boron were found to be present within the made ground and alluvium. This was thought to relate to natural elevated levels within local soils. Copper and zinc concentrations within the made ground exceeded the generic screening criteria. On the basis of these exceedances, Hydrock concluded that mitigation may be required and recommended importing a clean growing medium for the proposed planting.
REP/004/21 | Issue | 16 April 2021 Page 9 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
4 Revised Conceptual Site Model
A conceptual site model was created by Hydrock in both the desk study and subsequent GIR. However, development proposals have since evolved, and it is understood that pollutant linkages previously identified may no longer be plausible. For this reason, a revised conceptual model has been developed and is presented in the following section. The potential risks to human health and the environment have been considered in the context of a conceptual source-pathway-receptor (SPR) model of the site, identifying: • The principal pollutant hazards associated with the site (the sources); • The principal receptors at risk from the identified hazards; and • The existence, or absence, of plausible pathways which may exist between the identified hazards and receptor. For risks to be present at the site, all three elements (source-pathway-receptor) of a plausible pollutant linkage must be present. Revised SPR linkages are described below based on the current development proposals.
4.1 Sources From a review of the existing environmental information pertaining to the site, including the Hydrock reports, a number of potential sources of contamination have been identified including made ground and historical land uses as detailed in Table 3. Although some evidence of hydrocarbon contamination has been encountered within the site area, no significant and/or on-going sources of contamination have been identified. However, it should be noted that the Hydrock Desk Study Executive Summary refers to future intrusive ground investigation being necessary to properly investigate a tank onsite. It is unknown where and when this tank may have existed as it is not referenced within the main body of report. Moreover, the Hydrock report documents a risk of unrecorded tanks and pits across the site. The Hydrock GIR makes no mention of such tanks onsite. Given the lack of evidence and further discussion on this feature, it is considered that this reference may be erroneous. However, further advice is given in Section 6.2.6 and 7.2.5 as to best practice for decommissioning and removal should a tank be encountered during the works. A number of off site sources have been identified in the vicinity of the site, from which contamination migration towards the site may occur primarily via groundwater. As discussed in Section 4.2, such lateral migration is unlikely to occur and therefore off site sources are unlikely to have significant impact on the site subsurface.
REP/004/21 | Issue | 16 April 2021 Page 10 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Table 3: Potential sources of contamination
Potential sources of Main potential contaminants associated with land use contamination Onsite Made ground Metals, metalloids, asbestos, PAH, petroleum hydrocarbons (including infilled pond) Evidence of Petroleum hydrocarbons, asbestos contamination Former brewery and VOCs, SVOCs (noted in Hydrock desk study as a source; GIR noted related works that there are no credible sources onsite) Warehouses Hydrocarbon fuels, lubricant, chlorinated solvents
Building fabric Asbestos
Ground gases from Carbon dioxide, methane organic material Natural soils Elevated metals
Deep geology Radon
Off site Former brewery and VOCs, SVOCs related works Workshops Hydrocarbon fuels, lubricant, chlorinated solvents
Malt house (incl. PAHs and TPHs, phenols, volatile organic compounds (VOCs), semi historical tanks) volatile organic compounds (SVOCs), BTEX Tobacco works (incl. PAHs and TPHs, phenols, volatile organic compounds (VOCs), semi historical tanks) volatile organic compounds (SVOCs), BTEX
4.2 Pathways For a risk to exist the source and receptor must be connected by a viable pathway. Potential pathways by which human receptors may be impacted upon are as follows: • Ingestion of contaminated soils and dust; • Dermal contact with soils and dust; and • Inhalation of vapours, dust and gases. During construction, the above pathways are likely to be viable. Particularly, during material sorting by hand to source stone for perimeter wall. However, the proposed development comprises only buildings and hardstanding in all three areas: commercial, a residential block of apartments and townhouses, and therefore, the only viable pathways would be inhalation of vapours and gases during permanent operation.
REP/004/21 | Issue | 16 April 2021 Page 11 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
For potential pathways by which controlled waters may be impacted, there is very limited potential for leachate generation as the site is currently and is proposed to be covered completely by hardstanding and buildings. The only area where there is potential for leachate generation is where groundwater infiltrates the made ground (i.e. in the area of the historical infilled pond), or if an ongoing source of contamination is present e.g. a leaking tank. However, when the cohesive nature of the ground encountered beneath the site is considered, it is unlikely that significant lateral migration of impacted groundwater would occur towards identified off site controlled waters receptors. Clay rich alluvium underlying the made ground is anticipated to act as a barrier to significant flow or contamination migration. It is therefore considered unlikely that any site contamination would migrate off site towards controlled water receptors. Furthermore, groundwater monitoring as part of previous investigations indicates water levels to be below that of the made ground (except for the infilled pond). It is therefore unlikely that there will be sufficient head in the made ground to drive contaminant flow into the underlying Secondary A aquifer. A preferential pathway for vertical migration through historic subsurface structures, for example, historical piles and/or service corridors may already be present onsite. In addition, some of the proposed buildings are likely to require deep pile foundations, depending on the type and method of piling, there is a potential for creation of new preferential flow paths for ground gas and groundwater vertical migration. New service corridors may also be created as part of the proposed development.
4.3 Receptors The receptors considered to be relevant to any existing contamination are identified as follows: • Site end users (commercial workers, residents of both apartment block and townhouses); • Construction workers involved in the development; • Maintenance workers following construction; • Onsite controlled waters, i.e. groundwater (Secondary A aquifers in alluvium deposits); • Building materials used in the proposed development; • Offsite residents, workers and users of the surrounding area; and • Offsite controlled waters, i.e. Secondary A aquifer and River Avon.
4.4 Summary The identification and justification of the plausibility of the above SPR linkages are presented in Table 4. SPR that are deemed ‘unlikely’ are not taken forward for further assessment.
REP/004/21 | Issue | 16 April 2021 Page 12 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Internally, the ground floor of the residential apartments will feature a well- ventilated carpark and plantrooms. The commercial buildings feature offices on the ground floor. The townhouses include ground floor residential accommodation, although it is understood external spaces will be covered by hard standing. Site end users will be isolated from site soils through building footprint effectively breaking the pathways for ingestion and dermal contact. It is considered that the only plausible pathway to end site users within the buildings is through the inhalation of vapours from volatile substances. Though this pathway is viable, it is considered to be a low risk. Externally, the site will be covered by hardstanding. The remainder of the site will be covered by building footprints. Raised planters (proposed in commercial area and residential outdoor space) will be provided with clean imported soils suitable for use as a growing medium. The external areas of the townhouses are proposed to be paving stone and patios. As the townhouses remain under the management of the developer, there is a minimal risk of uncontrolled land use change and exposure of subsurface soils. On this basis the only valid pathway is vapour inhalation, since building footprints and hardstanding will prevent dermal contact or ingestion routes and the generation of dust from site soils. It is not considered likely that a vapour inhalation scenario would be realised in external areas during the site use due to the potential for mixing with ambient air and subsequent dilution and dispersion. On this basis it is not considered that there are plausible pathways between the contaminants present in the site soils and end site users in external areas of the development. As the proposed end use does not allow for areas of soft landscaping it does not align with the end use scenarios on which generic published screening criteria are based. However, for the purpose of the initial screen a ‘residential without plant uptake’ (RWPU) and ‘commercial’ criteria have been adopted for the initial assessment, which is considered conservative. Exceedances of these are then discussed in relation to plausible pathways operating onsite. In regard to controlled waters, there is considered to be a limited potential for leachate generation and subsequent lateral migration. Soil leachate testing undertaken on made ground materials indicated the presence of leachable metals and PAH compounds. In addition, evidence of isolated hydrocarbon contamination in made ground has been recorded. However, due to limited potential for rainwater infiltration with minimal leachate generation and the cohesive nature of superficial deposits where groundwater is present, no measurable impact on groundwater quality has been identified. The final development will maintain the current infiltration regime, and therefore, no change to current risk levels in relation to controlled waters is anticipated. However, during construction works there will be an increase in potential for rainwater infiltration into the made ground as a result of removal of hardstanding. This will be temporary and unlikely to result in significant impact on identified controlled waters receptors due to limited lateral migration within superficial deposits.
REP/004/21 | Issue | 16 April 2021 Page 13 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Table 4: S-P-R likelihood
Potential Potential Receptor Possible Pathway Likelihood Comment Source Onsite End Site users: Direct dermal Unlikely It is anticipated that the likelihood of site end users coming into dermal Commercial workers, Inhalation of dust and asbestos Unlikely contact, inhalation of dust and ingesting contamination is unlikely, given residents of apartment Made ground fibres the future development will be entirely covered by hardstanding and (including block and town houses buildings. infilled pond) Ingestion Unlikely
Inhalation of vapours / ground Low Evidence of gas likelihood There is a risk of inhalation of gases and vapours, which will be taken contamination forward for further consideration and assessment. (petroleum hydrocarbons, Construction Workers/ Direct dermal Likely Construction workers and maintenance workers are considered likely to asbestos) Maintenance Workers Ingestion Likely come into direct contact with soils that may be contaminated, and perhaps
groundwater should deeper excavations be required or during piling Former activities. brewery and related works It should be noted that much of the risks presented to construction works Inhalation of vapours, dust and Likely can be mitigated through the appropriate health and safety management Warehouses asbestos fibres systems including the use of PPE. Advise from a specialist contractor will Contact with contaminated Likely be required in relation to asbestos. Building groundwater fabric Perched / deep Leaching into groundwater Unlikely Groundwater Body and subsequent flow beneath Limited potential for lateral contaminant migration due to cohesive nature of the ground beneath the site Ground gases (Secondary A Aquifer) site from organic Preferential pathway for Low Although the existing subsurface structures may already allow migration, material migration through historical likelihood new deep foundations may create new pathways and this will require and new subsurface structures assessment as part of detailed design, in the form of a foundation works Natural soils including piling. risk assessment.
REP/004/21 | Issue | 16 April 2021 Page 14 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Potential Potential Receptor Possible Pathway Likelihood Comment Source Building Direct contact with building Unlikely Attack of buried concrete from aggressive ground conditions has been Deep geology Materials/Potable pipes materials and ground gas identified as a hazard by Hydrock. They have undertaken concrete migrations classification appraisal and identified a suitable concrete class. However, Hydrock identifies a risk that unidentified aggressive made ground could Off Site occur. Former Off site Surface water Surface water run off Unlikely brewery and The River Avon is circa 300m from the site and the geology is anticipated related works (River Avon) Leachate and migration within Unlikely to include cohesive deposits, which prevent significant contamination subsurface. migration. It is therefore unlikely that any significant contamination could Workshops reach the River Avon receptor. Contaminated groundwater Unlikely and migration within the Malt house subsurface (incl. Off site residents and Ingestion and inhalation of Likely This can be mitigated by suitable dust suppression measures adopted historical workers during airborne dust and asbestos during works to limit this risk as part of site pollution control and health tanks) construction fibres and safety management.
Off site residents and Unlikely Future development will be entirely covered by hardstanding and Tobacco workers during buildings and therefore it is unlikely off site workers will come into works (incl. operations contact with dust and asbestos fibres. historical tanks) Off site surface waters Deposition of airborne dust Unlikely It is considered that suitable dust suppression measures will be adopted during works to limit this risk as part of site pollution control and health and safety management. Further, the River Avon is circa 300m from the site, it is therefore unlikely dust would extend this far. Off site groundwater Migration of contaminated site Unlikely The geology is anticipated to include cohesive deposits which prevent groundwater contamination migration to the local Secondary A aquifer. No licenced groundwater abstractions are reported within 1000m of the site.
REP/004/21 | Issue | 16 April 2021 Page 15 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
4.5 Relevant pollutant linkages The Relevant Pollutant Linkages (RPLs) that are considered to pose a risk to identified receptors will require further assessment. These are set out in Table 5 below. Table 5: Identified relevant pollutant linkages
RPL Potential Source Potential Possible Pathway Mitigation Measure No. Receptor Temporary linkages present during construction 1 Known risk (during Site neighbours, Inhalation/ingestion Suitable dust suppression construction): construction of dust measures to be employed made ground workers Dermal contact during construction. Suitable PPE adopted during works impacted by Ingestion contamination other with particular advice from
than asbestos (see specialists in relation to RPL2) asbestos. Best practice Health and Safety measures during
construction and maintenance works. Refer to Section 6.2.1. 2 Known Risk: Site neighbours, Inhalation and Suitable PPE adopted during Asbestos fibres in construction ingestion of dust and works with particular advice the made ground workers fibres from specialists in relation to asbestos. Best practice Health and Safety measures during construction and maintenance works. Refer to Section 6.2.2. 3 Unexpected Construction Dermal contact Adoption of contingency plan contamination workers Ingestion for unexpected contamination and watching brief by suitably Site neighbours Inhalation of qualified or briefed personnel. Controlled vapours/soil dust Refer to Section 6.2.3. waters
4 UXO Construction Encountering during UXO safety awareness workers and site earthworks or piling training to be given to site neighbours works personnel of all levels, alongside, selected individuals working on the project with relevant responsibilities. Refer to Section 6.2.4. 5 Piling arisings with Construction Dermal contact Foundation Works Risk contaminated soils. workers and site Ingestion Assessment required on neighbours confirmation of foundations Contaminated Inhalation of design. Refer to Section 6.2.5. perched water and Controlled dust/fibres groundwater waters Vertical migration along the pile 6 Unknown risk: Construction Dermal contact Any storage tanks and Possible onsite fuel workers, Ingestion associated infrastructure controlled encountered during works are tanks Inhalation of waters, to be decommissioned and vapours/soil dust residence removed as part of the
REP/004/21 | Issue | 16 April 2021 Page 16 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
RPL Potential Source Potential Possible Pathway Mitigation Measure No. Receptor Vertical and development. Excavations in horizontal migration this area may result in elevated in the sub-surface. vapour release and specific PPE to address this risk to construction workers should be provided. Refer to Section 6.2.6. Permanent Linkages 7 Vapours / ground Future site users Inhalation Confirmation of risk through gas (residents, Vertical migration further assessment. Refer to workers, along the pile Section 5. maintenance Foundation Works Risk workers) Assessment required on confirmation of foundations design. Refer to Section 6.1.4. 8 Radon Future site users Inhalation Design to incorporate basic (residents, workers) radon protection measures - likely to include a well- installed DPM modified and extended to form a radon barrier across the ground floor of proposed buildings. Refer to Section 6.2.7.
REP/004/21 | Issue | 16 April 2021 Page 17 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
5 Revised Risk Assessment
Plausible pollutant linkages have been identified in relation to human health and ground gas during the operation of the site. A revised risk assessment has been undertaken to confirm the risk present during the end use of the site. For temporary RPLs identified during the construction phase of the works, the Contractor shall undertake their own risk assessments, method statements and other necessary measures in relation to the safe management of contamination onsite. The above should be detailed in the Construction Environmental Management Plan to mitigate risks during construction. Recommendations pertaining to RPLs identified during the construction phase are provided in Section 6.2.
5.1 Human health The results of the chemical analysis undertaken on soil samples obtained from across the site during the Hydrock 2018 investigations have been reviewed and compiled in Appendix C of this report. The assessment in relation to human health is presented below.
5.1.1 Assessment criteria In order to facilitate the most appropriate assessment of the chemical analyses, consideration is required with regards to the end use of the site and the RPL identified as part of the revised CSM. As detailed in Section 1.2, the proposed development is covered by either hardstanding or building footprint, with a combination of residential and commercial end use. Discussion on the plausible pathways operating post development is included in Section 4.4 and concluded only the vapour and gas intrusion pathway to be viable. In order to assess the risks to human health, the chemical analysis results of soil samples obtained from the site have been screened against published C4SL and S4UL values. Where GACs have not yet been published for some contaminants, Arup derived in-house generic assessment criteria have been used. Appendix D details the derivation of such values.
5.1.2 End site users For the assessment of future site users, the revised CSM indicates that the entirety of the site is to be covered by hardstanding or buildings. The vapour inhalation risk from site soils is considered the only viable pathway for site end-users. The most sensitive receptor through the inhalation of vapours are considered to be future occupiers of the commercial and residential properties. Therefore, the results of soil testing have been initially screened against assessment criteria for a ‘RWPU’ and ‘commercial’ land use. These are considered to be overly conservative as the values consider the dermal, ingestion, and inhalation
REP/004/21 | Issue | 16 April 2021 Page 18 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
pathways, while the revised CSM has indicated only the vapour inhalation pathway to be present.
5.1.3 Averaging areas On account of the likely difference in chemical nature between the made ground and the underlying alluvium, these strata have been assessed in isolation. A review of available borehole logs suggests made ground stratum is of similar composition across the entire site, including the infilled pond, and for this reason all made ground will be included as one averaging area. Where data sets are large enough, and there is sufficient confidence that sampling was non-targeted, statistical analysis has been undertaken in line with CL:AIRE guidance: ‘Comparing Soil Contamination Data with a Critical Concentration’ [8]. The assessment will help to identify whether contamination within the made ground has impacted the alluvium below and/or if there are any natural background concentrations of contaminants within the natural soils.
5.1.4 Tier 1 soil assessment The following assessment is based on the applied RWPU and ‘commercial’ screening criteria for the assessment of vapour risk to site end users.
5.1.5 Made Ground The results from the 35No. made ground soil samples collected as part of the 2018 Hydrock investigation indicated the following: Inorganics • Asbestos was detected in 4No. samples as a hard cement type material, loose fibres or loose fibrous debris. Concentrations were recorded between from 0.001% to 0.015% wt. Heavy metals • Beryllium exceeded the residential criteria of 1.72mg/kg in 7No. samples with concentrations of 1.8-4mg/kg. • Copper exceeded the residential criteria of 7130mg/kg in 1No. sample with concentrations of 16000mg/kg. • Lead exceeded the residential criteria of 310mg/kg in 7No. samples with concentrations of 320-2100mg/kg. TPHs and BTEX • No exceedances of the residential or commercial screening criteria were identified. Evidence of visual and olfactory contamination has been detailed in Section 3.2. With the exception of BH01A, TPH and BTEX testing has been undertaken where visual and olfactory evidence of contamination has been noted. Testing did not identify elevated levels of volatile petroleum compounds.
REP/004/21 | Issue | 16 April 2021 Page 19 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
PAHs • Naphthalene exceeded the residential criteria of 2.33mg/kg in 2No. samples with concentrations of 5.5 and 2.9mg/kg; • Benzo[a]anthracene exceeded the residential criteria of 5.3mg/kg in 4No. samples with concentrations between 17 and 87mg/kg; • Chrysene exceeded the residential criteria of 29.66mg/kg in 3No. samples with concentrations between 37 and 78mg/kg; • Benzo[b]fluoranthene exceeded the residential criteria of 3.95mg/kg in 7No. samples with concentrations between 4.1 and 99mg/kg. Benzo[b]fluoranthene exceeded the commercial criteria of 44.3mg/kg in 3No. samples with concentrations between 47 and 99mg/kg; • Benzo[a]pyrene exceeded the residential criteria of 5.3 mg/kg in 7No. samples with concentrations between 3.5 and 88mg/kg; • Dibenz[ah]anthracene exceeded the residential criteria of 0.31mg/kg in 11No. samples with concentrations between 0.46 and 11mg/kg. Dibenz[ah]anthracene exceeded the commercial criteria of 3.53mg/kg in 3No. samples with concentrations between 4.7 and 11mg/kg.
5.1.6 Alluvium The individual analytical results of 3No. samples taken from the alluvium indicate no exceedance of the RWPU or commercial assessment criteria.
5.1.7 Potential contaminants of concern The tier 1 assessment has identified a number of heavy metals, asbestos and PAH exceedances. However, as detailed in Section 4.5, the site is to be covered by either hardstanding or building footprint, and therefore only the vapour intrusion pathway is considered viable. Consequently, only contaminants that are considered volatile have been considered further. Naphthalene is considered the only exceedance relevant to the vapour intrusion pathway. Naphthalene has the highest vapour pressure of the PAHs at 36.81Pa at 25°C [9]. It is therefore the only contaminant statistical analysis has been undertaken on.
5.1.7.1 Statistical analysis Statistical analysis of contaminant concentration has been undertaken in Microsoft Excel. Where results are indicated as below the limit of detection (LOD), the value has been taken as the LOD, providing a conservative estimate of contaminant concentrations. When the results are plotted, the data displays a log symmetrical distribution, with a minor number of elevated points controlling the mean value. The vast majority
REP/004/21 | Issue | 16 April 2021 Page 20 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
of points are significantly below the RWPU assessment criterion of 2.33mg/kg, which is reflected by a median value of 0.16. The results of the analysis have been summarised in Table 6 below. Table 6: Naphthalene summary statistics
Summary Statistics Result No. of samples 35 (2 exceedances) Maximum 5.5 Upper quartile 0.59 Median 0.16 Lower quartile 0.05 Minimum 0.05 Mean 0.56 Standard deviation 1.08 Interquartile range 0.54 80% confidence interval 0.32 – 0.8 95% confidence interval 0.19 - 0.93 99% confidence interval 0.06 – 1.06
As the dataset has a log symmetrical distribution, the apparent confidence interval may be somewhat exaggerated. This is because the addition of further elevated values not previously included in the sampling set could significantly increase the mean contaminant concentration. In this case the CL:AIRE guidance recommends a sample size of closer to 50 to increase the likelihood of such values being included. However, as the 99% confidence interval is significantly below the RWPU assessment criterion, even if this confidence interval is somewhat exaggerated, there is still sufficient confidence that the value would be below the RWPU criterion.
5.1.8 Conclusions Historical mapping indicates that site development occurred at a similar time, and when land use changed, buildings appear to have been repurposed, not demolished. Available borehole logs confirm the above, displaying made ground of similar composition across the site. There is, therefore, confidence that statistical analysis can be undertaken with the ability to average test results across the entirety of the made ground. Statistical analysis indicates a 99% confidence interval significantly below the assessment criteria for naphthalene (2.33mg/kg for RWPU). There is, therefore, confidence that the mean level of contamination on the site is low relative to an appropriate level of risk. No further action is therefore deemed necessary. The analysis indicates that limited vapour generation is occurring onsite. For this reason, RPL 7 is not considered viable with respect to vapour and will not be considered further.
REP/004/21 | Issue | 16 April 2021 Page 21 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
5.2 Ground gas The results from the Hydrock ground gas monitoring rounds indicated maximum CO2 levels of 4.9%v/V and no methane. In accordance with BS 8485:2015, this characterises the site as CS1. From a review of the nature of the made ground encountered during the ground investigations and identified historical features such as infilled pond, in accordance with BS 8485:2015 the site has a low ground gas generation potential. Therefore, the existing three monitoring rounds are considered sufficient to characterise the site. Consequently, the completed ground gas risk assessment and derived site classification is considered to be adequate. Therefore, no additional monitoring or gas protection measures are considered necessary. Hydrock recommended gas protection measures to mitigate against nuisance odours generated from hydrocarbon and VOC contamination, however, the revised assessment does not indicate significant hydrocarbon or VOC contamination onsite. Therefore, no additional mitigation measures are required. The analysis indicates that limited ground gas generation is occurring onsite. For this reason, RPL 7 is not considered viable with respect to ground gas and will not be considered further.
5.3 Summary of revised risk assessment The revised risk assessments have been undertaken for the current project proposals as outlined in Section 1.2, where the site will be entirely covered by hardstanding or building footprint. Currently no landscaping is proposed. Raised planters will be provided with clean imported soils suitable for use as a growing medium. Should the proposed development change, revised assessments would need to be undertaken. The results of the revised risk assessment have alleviated RPL 7 as there is not significant ground gas or vapour generation occurring onsite. Therefore, the following RPLs have been considered further: • Made ground impacted by contamination other than asbestos - RPL1; • Asbestos fibres in the made ground - RPL 2; • Unexpected contamination - RPL 3; • UXO - RPL 4; • Piling arisings with contaminated soils - RPL 5 • Possible onsite fuel tanks - RPL 6; and • Radon - RPL 8.
REP/004/21 | Issue | 16 April 2021 Page 22 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
6 Remediation Objectives and Strategy
The following section retails the remediation strategy to mitigate against the risks posed by the RPLs identified in Section 4.5. The mitigation should ensure that no short or long term risks of harm or pollution are posed to the identified receptors during or post construction.
6.1 Site wide non RPL specific Construction of the proposed development will not require significant earthworks as no basements are proposed. Minor earthworks will take place as part of the demolition works potentially followed by some site levelling, which will require excavation and placement of materials across the site to achieve the development level. These activities will require implementation of generic measures to mitigate risks to the identified receptors.
6.1.1 Watching brief Based on the site history there is a potential to encounter unexpected contamination. There is also a risk of encountering unidentified underground storage tanks – refer to Section 6.2.6 for more details. Therefore, a watching brief is recommended. A watching brief is to be undertaken onsite throughout the ground works. The method for implementing the watching brief should be described in the construction method statement produced by the contractor for the works. The watching brief will involve full time specialist personnel and should be defined onsite, communicated to staff involved in the ground works (toolbox talks, etc.) and reported on. The watching brief will identify any soils encountered and displaying visual or olfactory evidence of contamination and ensure these are managed appropriately, in accordance with this document. Where it is necessary to sample and test soils for classification purposes, this should be undertaken in an appropriate manner by specifically experienced and qualified staff. The watching brief will observe and record any materials excavated as part of the works, either during grading, foundation construction, service or utility excavations, ensuring these are managed and removed from site appropriately and that any imported clean backfill is placed into any excavations and/or used in filling works.
6.1.2 Earthworks and material management Grading and earthworks will likely be required to reach formation level outside of the buildings. Service and utility trenches will also require excavation to facilitate the proposed development. At present, based on development proposals, there is little scope for the re-use of site won materials on the site.
REP/004/21 | Issue | 16 April 2021 Page 23 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
On account of the presence of asbestos, in addition to the presence of metals and PAHs, site won materials are only deemed suitable for re-use below hardstanding. Any materials displaying bulk asbestos and/or visual or olfactory evidence of contamination are not considered suitable for re-use in the development. All materials destined for off site disposal are to be managed in accordance with current waste management guidance. If dewatering is required as park of construction, there will be a requirement for it to be discharged off site. The permission of the regulators must be obtained prior to discharge. Applications for discharge consents should be commenced in advance of construction to allow any constraints to be identified, e.g. discharge consents often define maximum limits for suspended solids. Should the groundwater display any visual or olfactory evidence of contamination the water should be sampled and analysed, treated and/or disposed of. In accordance with current regulations, any dewatering activities from engineering works will require a temporary license where abstracting more than 20 cubic metres of water a day over a period of less than 28 days. A full licence will be required for most types of water abstraction over 20 cubic metres a day.
6.1.3 Removal of subsurface obstructions The Hydrock ground investigation [2] identified remnants of concrete foundations and buried services across the site. Hydrock anticipate obstructions associated with present and historical site development including foundations, floor slabs and buried services. There is also a potential for an unidentified underground storage tank to be present onsite. Where present, subsurface obstructions will require removal. As detailed in Section 6.1.1, a watching brief shall be maintained for the duration of these works and any encountered contamination should be removed and verified in line with Section 7 of this document.
6.1.4 Decommissioning of existing monitoring wells Numerous monitoring wells are present across the site, these should be decommissioned prior to demolition works. Boreholes should be decommissioned in line with the EA guidance [10]. In accordance with that guidance the Contractor shall: • Remove all pipework and headwork, and • Backfill the wells with clean, uncontaminated materials such as concrete, bentonite or cement grout. It is envisaged that this work will be undertaken as part of the initial site clearance works.
REP/004/21 | Issue | 16 April 2021 Page 24 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
6.1.5 Remediation of contaminated made ground No remediation of made ground is required. Although elevated levels of metals and PAHs have been identified, as part of the proposed development, made ground soils will be covered by hardstanding or building footprint, providing a pathway break between the identified contaminants and receptor. It is recommended that raised planter pots include a clean imported growing medium, in accordance with the proposed mitigation measures for asbestos as outlined below. The imported soils should enable healthy plant growth, in accordance with BS3882 [11]. The presence of PAHs and metals within the subsurface should be recorded in the Health and Safety file for the site, particularly to inform any future maintenance workers of risks posed from contaminants within the subsurface. To mitigate against future exposure of maintenance workers to potentially contaminated site soils clean service corridors will be constructed across the site provided with acceptable backfill complying the specification outlined in Section 8.
6.1.6 Remediation of asbestos impacted made ground No remediation of made ground due to the presence of asbestos fibres and ACM is required. Although asbestos has been identified, as part of the proposed development, made ground soils will be covered by hardstanding or building footprint, providing a pathway break between the asbestos impacted soils and receptor. Landscaping will be limited to contained planter pots placed on hardstanding, only the requirements of the landscape architect and chemical criteria set out in Section 8 are relevant. The presence of asbestos within the subsurface should be recorded in the Health and Safety file for the site, particularly to inform any future maintenance workers of risks posed from asbestos within the subsurface. With respect to the health and safety of future maintenance workers, it is not recommended that materials containing asbestos are re-used in any service runs. Any service trenches will require lining and backfilling with clean imported fill, meeting the requirements as set out in Section 8. A permit to work system shall be instigated for all intrusive maintenance works proposed below the marker sheet during development or operation of the site. This shall include future tree planting or any similar activities.
6.1.7 Contaminated groundwater No contaminated groundwater has been encountered within the site, however there is a risk localised groundwater contamination. The contractor shall acknowledge the risk of encountering contaminated groundwater during the works and adopt appropriate health and safety briefings and PPE as considered necessary.
REP/004/21 | Issue | 16 April 2021 Page 25 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
Should construction works require dewatering there will be a requirement for encountered groundwater to be discharged. Considering the site setting, discharge options would include either discharge into the ground (although likely to be limited due to cohesive nature of the natural ground) or sewers. This may require a discharge permit from the regulators or a permit from the sewer operator. Applications for the permits should be commenced in advance of construction to allow any constraints to be identified, e.g. discharge consents often define maximum limits for suspended solids. Should the groundwater display any visual or olfactory evidence of contamination the water should be sampled and analysed, treated and/or disposed of.
6.2 RPL specific
6.2.1 Working with contaminated made ground soils – RPL 1 Construction workers and site neighbours have the potential to be exposed to contamination present in the site soils during the period of construction works as detailed under RPL 1. In order to mitigate against the potential harm, specific site safety and control measures should be implemented onsite and these shall be detailed by the Contractor in their Construction Environmental Management Plan (CEMP). A summary of the outline guidance that should be included is provided below: • Appropriate measures to protect construction workers may include training in and enforcement of hygiene procedures, use of personnel protective equipment and the implementation of pro-active dust control measures; • Procedures and protocols to prevent construction workers, visitors and neighbours from being exposed to contaminated materials; • Monitoring of excavation works to identify unforeseen areas of contamination (a watching brief – refer to section 6.1.1); and • Systems to record and monitor the movement and deposition of waste materials leaving or being transported to other parts of the site.
6.2.2 Working with asbestos impacted made ground soils – RPL 2 Construction workers and site neighbours (via dust generation) have the potential to be exposed to asbestos fibres present within the subsurface during the period of construction works as detailed under RPL 2. Work with asbestos in the UK is controlled by the health and Safety Executive and the Control of Asbestos Regulations 2012 (CAR) [12]. The Contractor should undertake specific assessments and mitigation described in the CAR. Works with asbestos lagging and some other materials are likely to require a licensed contractor and may require notification to the HSE in advance. The following published guidance on asbestos should also be reviewed and applied where applicable:
REP/004/21 | Issue | 16 April 2021 Page 26 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
• CIRIA C765 guidance on Asbestos in soil and made ground – good practice site guide. • Specific advice on works with ACM in accordance with current guidance including CIRIA [11] and HSE guidance [13]. • Reference to relevant standards and regulations [12] [14] [13]. To mitigate against the potential harm, specific site safety and control measures should be implemented onsite and these shall be detailed by the Contractor in their Construction Environmental Management Plan (CEMP). The services of a specialist asbestos contractor should be sought to confirm the required mitigation measures, including consideration of: • Sufficient hygiene units, decontamination units, welfare facilities and PPE, specific to asbestos, provided by the Contractor for the duration of the works. • Proactive prevention of dust generation by damping down etc, as set out in BRE 456 [15]. • Boundary fencing to control access to the worksite. • Boundary and representative personnel air/dust monitoring during work with made ground to confirm the absence of fibre release and exposure during the works. • Supervision of works onsite and staff briefing on the hazards and correct working methods. • Wheel washing system for vehicles entering or leaving the site if come into contact with potentially contaminated made ground to prevent the spread of contamination off site. The contaminated land officer at Bristol Council shall be notified prior to the onset of the proposed earthworks
6.2.3 Unexpected contamination – RPL 3 On the basis of the site history and potential for contamination, there is a risk that previously unidentified contamination may be present onsite and this has been identified as RPL 3. In order to mitigate against risk to the identified receptors a contingency plan to be implemented on encountering previously unencountered contamination is presented below: • Procedures and protocols to prevent construction workers, visitors and neighbours from being exposed to contaminated materials. • Monitoring of excavation works to identify unforeseen areas of contamination – watching brief. • Preventing dust generation during excavation and handling of potentially contaminated materials • Impacted soils should be excavated, stockpiled, and sampled. The materials shall be stockpiled separately from other materials in a designated area which shall be either on hardstanding or lined with an impermeable membrane and
REP/004/21 | Issue | 16 April 2021 Page 27 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
bunded to prevent migration of leachate or soils from the stockpile. The materials will need to be covered with an impermeable membrane to prevent dust, rain run-off, and leachate generation. • Sampling should be undertaken by a suitably qualified and experienced person, who is aware of the remediation objectives. The laboratory analysis should be undertaken in accordance with MCERTS validated methodology. • On receipt of the testing results an assessment will be required as to the nature of contamination present and the potential risk to human health and the wider environment. This will determine whether the soils are suitable to remain onsite, require treatment or potentially offsite disposal to a licensed waste facility. • Notification of the unexpected contamination shall be made to the contaminated land officer at Bristol City Council and it should be recorded in the validation report for the works.
6.2.4 Unexploded ordnance – RPL 4 Previous assessment for the site has indicated that the risk from Unexploded Ordnance (UXO) onsite is low [1] [4]. The UXO report made the following recommendations with respect to the management of UXO on the site: • UXO Safety and Awareness Briefings – All personnel working on the site should receive a general briefing concerning the identification of a UXO, what actions they should take to keep people and equipment away from such a hazard and to alert site management. Poster and information concerning the general nature of the UXO threat should be held in the site office and displayed for general information on notice boards, both for reference and as a reminder for ground workers. The safety and awareness briefing is an essential part of the Health and Safety Plan for the site and helps to evidence conformity with the principles laid down in CDM.
6.2.5 Piling works and contaminated pile arisings – RPL 5 The assessment of potential introduction of new contaminant pathways with respect to the proposed piling works onsite is to be assessed in a Foundation Works Risk Assessment (FWRA) for the site, to be undertaken in accordance with Environment Agency guidance [15]
6.2.6 Potential for below ground fuel infrastructure – RPL 6 If any underground fuel storage tanks and associated infrastructure are encountered during the works these shall be decommissioned and removed from site. This shall be undertaken in line with the Pollution Prevention Guideline (PPG) 27 [16], although it is noted that this guidance is withdrawn, its main principles shall still be followed onsite. A summary of the proposed remediation measures are provided below. On encountering fuel tanks or fuel infrastructure onsite:
REP/004/21 | Issue | 16 April 2021 Page 28 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
• A specialist contractor shall be appointed to access the tank and confirm contents if any. • Content of the tanks shall be emptied via vacuum tanker and removed by a specialist contractor to a suitably licenced waste facility. • Empty tanks will be cleaned and pipe work flushed and any washing collected by vacuum tanker and disposed of at a suitably licensed recycling facility. • Following cleaning, tanks shall be vented and the atmosphere within the tank tested for volatile gases. • Once confirmed as clear tanks can be broken/crushed prior to being removed and exported to a suitably licenced waste facility. • Connected pipework will be inspected disconnected and removed to a suitably licenced waste facility. • Inspection of soils by geo-environmental engineer for visual or olfactory evidence of hydrocarbon contamination in location of fuel tanks and infrastructure following removal. • Upon identification of any contaminated material, the excavation shall be extended as necessary laterally and in depth until all contaminated material is removed. If contaminated material is still present at the base of the made ground an assessment shall be made as to whether further excavation is needed. This shall be based on a decision made between the Contractor and the Project Manager, and with regulatory agreement. • The Contractor shall record the remediation works undertaken. This shall include sketches of excavation size with accurate measurements of the perimeter and depth of the excavations, supported by photographic evidence, and shall include records of the vertical/horizontal location of contaminated materials and its approximate volumes. This information shall be prepared for inclusion in the verification report. • On completion of excavation works, validation shall be undertaken in accordance with the requirements presented in Section 8. • The excavation shall be suitably backfilled on completion in accordance with all requirements of the specification for the scheme. • Soils arisings management shall be undertaken as detailed in Section 6.1.2 and Section 7.1.1. • If no evidence of contamination is noted, excavations will be backfilled with arisings. • Any contaminated groundwater encountered during the excavations shall be removed prior to discharge as detailed in Section 6.1.2.
6.2.7 Radon– RPL 8 The building design should incorporate basic radon protection measures to mitigate against elevated radon levels, with the majority of the site within an area of 3-5% of properties at or above the action level.
REP/004/21 | Issue | 16 April 2021 Page 29 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
The design will likely feature a well-installed DPM modified and extended to form a radon barrier across the ground floor of proposed buildings. Guidance detailed in BRE Report BR211 on protective measures for new buildings should be followed [17].
REP/004/21 | Issue | 16 April 2021 Page 30 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
7 Verification plan
The following measures shall be completed as part of the remedial works and will be documented by the Contractor in the form of a Validation Report.
7.1 Non RPL specific
7.1.1 Earthworks and materials management Should any site won made ground materials be re-used on the site, a record of the origin, volume and location of placement shall be kept by means of a material tracking plan. Record of materials validation prior to reuse, such as materials description and photographs, will need to be presented in validation report. Surplus arisings from earthworks or these not suitable for reuse will require off site disposal. All waste transfer notes and haulage tickets are to be kept and included in the validation report to confirm all materials removed from site were managed and disposed appropriately, in accordance with current waste management guidance. A record of any groundwater sampled and analysed and/or removed or treated is to be kept and included in the report. A record of any dewatering activities and any associated licenses and/or permits are to be kept. Where temporary stockpiling is proposed, stockpiles shall be formed so as to prevent the spread of contamination. Measures shall be taken to restrict dust and surface water run-off from temporary stockpiles, to include placement of the material on an impermeable layer which is robust enough to withstand trafficking by vehicles, bunded to prevent run-off and with a closed drainage system, which collects in a sump to allow for specialist disposal of any surface water within the stockpile area. A stockpile register shall be kept by the Contractor.
7.1.2 Decommissioning of monitoring wells Complete and accurate records shall be kept of the abandonment procedures of decommissioned monitoring wells for inclusion in the Validation Report. The following records shall be kept: • Depth of excavation of headwork and pipe work • Details of the backfill chosen to mimic the natural geology (alluvium and Mercia Mudstone) including volumes of backfill used and depth of each layer (if different layers are required to mimic the geology). • Details of the construction of the impermeable plug and cap. • Any problems encountered during the procedure. • Abandoned/decommissioned monitoring well locations should be marked onsite drawings.
REP/004/21 | Issue | 16 April 2021 Page 31 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
7.1.3 Verification of imported materials Materials imported to site from an off site source should be sampled and tested at a frequency of the following: • 4No. Samples if imported volume is between 20m3 to 250m3 • 4No. Samples per 250m3 (if imported volume is greater than 250m3). The results will be screened against the verification criteria for either materials placed at the site surface as detailed in Table 7 and Table 8 or for placement beneath hardstanding or buildings (Table 8 if re-used near or below the water table and Table 9 for placement below hardstanding). A desk study is required for the location of each source of imported materials. Confirmation that the source is acceptable through review of up to date test results and desk study information to ensure that an appropriate suite of analyses has been undertaken, will be undertaken in advance, prior to the materials being brought to site. Validation sampling shall be undertaken by a suitably qualified person (i.e. environmental engineer/scientist). The results of verification testing will be provided to the employer’s representative on receipt and included in the Validation Report. Materials sourced from a registered supplier in bulk or bagged form (e.g. quarry or builders merchants etc.) shall be accompanied (from each supplier) with the relevant testing certificates and will not require additional testing.
7.1.4 Verification of site won materials It is envisaged that site won soils (made ground and natural strata) will be suitable for re-use without testing if reused beneath hardstanding and building footprints providing that they are above groundwater table, geotechnically suitable, free from ACM and significant visual and/or olfactory evidence of contamination. Site won made ground materials placed below groundwater table should be sampled and tested at a frequency of the following: • 4No. Samples if reused volume is between 20m3 to 250m3 • 4No. Samples per 250m3 (if reused volume is greater than 250m3). The results should be screened against the verification criteria set out in Table 8. Where no testing is required, visual verification against the criteria set out in Table 9 will be required. Results of any material verification should be included in the Validation Report.
7.1.5 Temporary stockpiling If clean, imported soil is to be stockpiled for any length of time, it is important that it is stockpiled correctly to avoid damage to the physical and chemical quality
REP/004/21 | Issue | 16 April 2021 Page 32 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
of the soil. The Contractor will provide a detailed methodology for the stockpiling of topsoil and subsoil, but it is recommended that the guidance provided in the Defra publication “Construction Code of Practice for the Sustainable use of Soils on Construction sites” [18] is followed. Any materials displaying evidence of contamination shall be stockpiled separately in a designated area and in an appropriate manner i.e. on an impermeable and bunded surface. Stockpiles shall be covered with an impermeable membrane to prevent dust creation, rain run-off and leachate generation
7.1.6 Contaminated groundwater All correspondence pertaining to discharge consents, pumping and/or treatment and disposal from site of contaminated groundwater should be retained and included in the Validation Report. This is to include volumes of groundwater discharged from site, either to sewer or by tanker.
7.2 RPL specific
7.2.1 Working with contaminated made ground soils – RPL 1 and 2 The following information shall be collated by the Contractor as part of the Verification Report: • Details of site welfare provisions; • Details of PPE requirements adopted during the works with specific focus on any specialist advice and requirements; • Results of personnel monitoring and boundary fence monitoring for asbestos fibre detection; • Records of correspondence with the HSE and the Local Authority/EA with regards to contamination; • Records of any notifiable works with regards to asbestos contamination and remediation; • Details suitably qualified personnel (contaminated land specialists etc.) to supervise works onsite and brief staff of the hazards and correct working methods; • Details of methods used to prevent generation of dust, fouling of highways etc; and • Details of any complaints arising from site users or neighbouring site users during the works.
REP/004/21 | Issue | 16 April 2021 Page 33 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
7.2.2 Unexpected Contamination – RPL 3 Should areas of unexpected contamination be found onsite during the proposed works, the following validation records and details shall be compiled as part of the Validation Report: • Records of the visual and olfactory identification during the watching brief (site diaries etc). • Location, extent of contamination and extent of excavation provided on mark ups of the approved for construction drawings. • Validation records of visual inspection of the excavation including materials description and photographs by a suitably qualified person (i.e. environmental engineer/scientist). As set out in Section 8.1.
7.2.3 Unexploded Ordnance – RPL 4 The following information shall be collated as part of the Validation Report • Records of the site inductions and briefings supplied and attendees.
7.2.4 Piling arisings with contaminated soils and piling pathways - RPL 5 A foundation works risk assessment is to be completed. Depending on the results of the FWRA, groundwater monitoring and sampling may be required during and post completion of the works. The results of this monitoring; undertaken to demonstrate no discernible impact of the piling works on the quality of the groundwater, should be included in the verification report.
7.2.5 Potential below ground fuel infrastructure – RPL 6 The removal of fuel infrastructure shall be in accordance with PPG 27 [19]. It should be noted that this has now been withdrawn but there has been no replacement guidance and as such it is still considered to be relevant in principle. The following records shall be obtained as part of the removal of fuel infrastructure on the site and included by the Contractor in the Verification Report: • Details of the persons responsible for the decommissioning of the infrastructure including: o Name of company and registered address; o Copies of licenses/certificates for undertaking the works; and o Details of the decommissioning, including volumes and type of removed product/fuels, cleaning records, waste transfer notes, details of the receiving waste facility and records of them receiving the wastes.
REP/004/21 | Issue | 16 April 2021 Page 34 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
• Location and extent of removed and (if applicable) remaining infrastructure detailed on an as built service drawings of the site. • Details of equipment removed, tanks, pipes, pumps etc. lateral extents and depths of excavations (surveyed). • Records of watching briefs undertaken during the removal of the infrastructure, observations of contamination, and remedial measure undertaken on this contamination. Sampling and testing are required to validate that all contaminated materials have been removed. This is set out in Section 8.
7.2.6 Radon– RPL 8 Verification to be undertaken in line with BRE Report BR211 [17]. Complete records should be kept of the radon protection measures installed. These should be detailed within the contactors Verification Report.
REP/004/21 | Issue | 16 April 2021 Page 35 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
8 Materials Verification
8.1 Excavation validation methodology Following excavation of contaminated materials, verification of the excavation will be required. This shall be undertaken on a visual basis. The following records of validation shall be compiled by the Contractor for inclusion in the Validation Report: • Records of the visual and olfactory identification during the watching brief (site diaries etc). • Records of the location and the nature of potential source (reference of fuel tank, interceptor etc.), if encountered. • Details of the location, extent of contamination and extent of excavation provided on mark ups of the approved for construction drawings. • Validation records of visual inspection of the excavation including materials description and photographs, details of excavation face and base.
8.2 Materials verification criteria
8.2.1 Chemical validation criteria for imported soils Table 7 sets out chemical validation criteria required for soils to be imported to the site for use as planter growing medium and service trench backfill with respect to human health. No specific criteria are proposed for general engineering fill for use beneath hardstanding and buildings with respect to human health. However, such materials shall be free of bulk asbestos and any visual or olfactory evidence of contamination, as set out in Table 8. Should imported materials be placed below the groundwater table, criteria set out in Table 8 shall be met. The landscape architect for the development should specify additional criteria as to ensure materials imported to site can achieve healthy plant growth. As a minimum imported topsoil shall also meet requirements of BS3882:2015 [11]. No import of materials classifying as hazardous waste is permissible. The validation criteria in Table 7 below are based on published guidance comprising C4SLs and S4ULs for RWPU. Table 7: Materials import criteria in relation to human health (planters and service trench backfill)
Soil analysis determinand Unit Criteria Arsenic mg/kg 37 (C4SL) Cadmium mg/kg 150 (C4SL)
REP/004/21 | Issue | 16 April 2021 Page 36 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
Soil analysis determinand Unit Criteria Chromium (III) mg/kg 907 Copper mg/kg 7130 Mercury (inorganic) mg/kg 56 Nickel (MS) mg/kg 181 Lead mg/kg 310 (C4SL) Zinc (MS) mg/kg 40400 Cyanides mg/kg 24 Asbestos (Note 2) No ACMs and <0.001% fibres Naphthalene mg/kg 2.3 Acenaphthylene mg/kg 2893 Acenaphthene mg/kg 2995 Fluorene mg/kg 2795 Phenanthrene mg/kg 1292 Anthracene mg/kg 30604 Fluoranthene mg/kg 1526 Pyrene mg/kg 3661 Benzo(a)anthracene mg/kg 11 Chrysene mg/kg 30 Benzo(b)fluoranthene mg/kg 3.95 Benzo(k)fluoranthene mg/kg 106 Benzo(a)pyrene mg/kg 5.3 (C4SL) Indeno(123cd)pyrene mg/kg 45 Dibenzo(a,h)anthracene mg/kg 0.31 Benzo(ghi)perylene mg/kg 355 TPH (Note 1) mg/kg 5000 Aliphatics >C5 - C6 mg/kg 42 Aliphatics >C6 - C8 mg/kg 104 Aliphatics >C8 - C10 mg/kg 27 Aliphatics >C10 - C12 mg/kg 132 Aliphatics >C12 - C16 mg/kg 1061 Aliphatics >C16 - C35 mg/kg 11925 Aromatics >C5 - C7 mg/kg 0.38 Aromatics >C7 - C8 mg/kg 880 Aromatics >C8 - C10 mg/kg 47.2 Aromatics >C10 - C12 mg/kg 252 Aromatics >C12 - C16 mg/kg 1800 Aromatics >C16 - C21 mg/kg 1400
REP/004/21 | Issue | 16 April 2021 Page 37 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
Soil analysis determinand Unit Criteria Aromatics >C21 - C35 mg/kg 1930 Note: 1. Materials exhibiting visual or olfactory evidence of hydrocarbon contamination or other potential contamination shall not be re-used within the development. The acceptance criterion for total petroleum hydrocarbons has been set at <5000mg/kg with the speciation of target values for the more sensitive hydrocarbon fractions. 2. Any imported material shall not contain evidence of ACM, bulk asbestos or asbestos fibres and shall comply with the criteria set above in the table
Table 8: Site won and imported materials verification criteria in relation to controlled waters (for use below groundwater table)
Determinand in soil Unit Acceptance Reference leachate criteria pH - 6 - 9 FEQS Arsenic µg/l 50 FEQS Cadmium µg/l 0.25 FEQS Chromium µg/l 4.7 FEQS Copper µg/l 1* FEQS Mercury µg/l 0.05 FEQS Nickel µg/l 4* FEQS Lead µg/l 1.2 FEQS Zinc µg/l 10.9* FEQS Cyanide (Total) µg/l 1 FEQS Phenol µg/l 7.7 FEQS Naphthalene µg/l 2 FEQS Benzo(a)pyrene µg/l 0.01 LOD Fluoranthene µg/l 0.01 LOD Anthracene ug/l 0.1 EQS Petroleum Hydrocarbons Materials exhibiting visual or olfactory evidence of hydrocarbon contamination shall not be placed below groundwater table. Note: * bioavailable
8.2.2 Site won materials Generally, there is limited scope for reuse of site won materials as part of the development. However, it is understood that stone from site is to be used for repairing and rebuilding the site perimeter wall. Suitable stones will be selected by hand and stored on site until reuse. Stone should be free from any visual or olfactory evidence of contamination. Where it is proposed to re-use other site won materials, it is considered that site won materials are suitable for re-use beneath hardstanding where the following criteria, as set out in Table 9 below, are met (in addition to any geotechnical
REP/004/21 | Issue | 16 April 2021 Page 38 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
requirements). In addition, should site-won made ground materials be placed below the groundwater table, criteria set out in Table 8 shall be met. Table 9: Site won criteria (below hardstanding).
Soil analysis determinand Unit Acceptance criteria (all sites)
Asbestos (see note 1) % w/w No bulk asbestos Hydrocarbons - No visual or olfactory evidence of hydrocarbons Note: Any site won material shall not contain evidence of ACM, bulk asbestos or asbestos fibres and shall comply with the criteria set above in the table.
8.3 Soil sample collection Samples shall be collected in accordance with: • BS 10175:2011+A1:2013 Investigation of Potentially Contaminated Sites - Code of Practice • BS 5930: 1999+A1:2010 Code of practice for site investigations • CIRIA Report 132. A Guide for Safe Working on Contaminated Sites, 1996 The size and type of sample and container, method of sampling and time limitations for carrying out specific analyses shall be commensurate with the range of tests to be carried out. The Contractor shall take all steps necessary to avoid cross contamination of different sampling points and shall take samples which are representative of each of the materials encountered. A clean stainless-steel trowel shall be used to collect soil samples for chemical testing, which shall be cleaned between samples. Solid samples shall be taken from the position at the time of excavation. Subsampling from bags or from excavations left open for sampling shall not be deemed appropriate for validation purposes. All soil and water samples to be selected for hydrocarbon analysis shall be stored appropriate containers to ensure samples are not classed as deviating. Soil samples for metals analysis shall be stored in plastic containers. Soil samples for leachability analysis shall be stored in plastic tubs. Soil samples for volatile hydrocarbon analysis shall be stored in glass vials. A single sample shall therefore comprise a number of different containers as described above. All soil and liquid samples shall be below a maximum of 8°C during storage and transport to an MCERTS accredited laboratory.
8.3.1 Sampling frequency Sampling frequency of imported materials is presented in Section 7.1.3 and Section 7.1.4.
REP/004/21 | Issue | 16 April 2021 Page 39 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton, Remediation Implementation and Verification Plan
References
[1] Hydrock Consultants Limited, “The Old Brewery, Southville, Ground Conditions Desk Study,” 2017. [2] Hydrock Consultants Limited, “The Old Brewery, Southville, Ground Investigation Interpretative Report,” 2018. [3] Bristol City Council, “Bristol - Know Your Place,” 26 July 2019. [Online]. Available: https://maps.bristol.gov.uk/knowyourplace/. [4] EOD Contracts Ltd, “Explosive Ordnance Desk Top Study,” 2018. [5] Environment Agency, “Remedial Targets Methodology. Hydrogeological Risk Assessment for Land Contamination,” 2006. [6] S. O. S. M. H. H. H. C. G. Wilson, “Assessing risks posed by hazardous ground gases to buildings,” 2007. [7] R. W. P. Boyle, “Guidance on evaluation of development proposals on sites where methane and carbon dioxide are present,” 2007. [8] CL:AIRE, “Comparing Soil Contamination Data with a Critical Concentration,” 2020. [9] Environment Agency, “Review of the Fate and Transport, Draft Technical Report P5- 079/TR1,” 2003. [10] The Environment Agency, “Good Practice for Decommissioning Redundant Borehols and Wells, LIT6478/657-12.,” The Environment Agency, 2012. [11] BRE, “Specification for Topsoil, BS3882:2015,” 2015. [12] Statutory Instrument, “The Control of Asbestos Regulations, No. 632,” 2012. [13] Health and Safety Executive, “Online Guidance,” [Online]. Available: https://www.hse.gov.uk/asbestos/. [Accessed 07 04 2021]. [14] CIRIA, “Asbestos in soil and made grund: a guide to understanding and managing risks,” 2014. [15] BRE, “Control of dust from construction and demolition activities, BRE 456,” 2003. [16] The Environment Agency , “Piling and Penetrative Ground Improvement Methods on Land Affected By Contamination: Guidance on Pollution Prevention, NC/99/73,” The Environment Agency , Solihul, 2001. [17] BRE, “BRE Report BR211: Radon: Protective measures for new buildings,” 2015. [18] DEFRA, “Construction Code of Practice for the Sustainable use of Soils on Construction Sites,” 2009. [19] The Environment Agency, “Installation, Decommissioning and Removal of Underground Storage Tanks: PPG27,” The Environment Agency.
REP/004/21 | Issue | 16 April 2021 Page 40 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Appendix A Development Proposals
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
P5 P5 revision revision CM DA SH checked by K2 JC A group.co.uk drawn by - PL0051 PL0051 J - - K1 A A - - B H3 ction with the specificationction with DR DR - - H1 H2 G 00 00 - - 16 Moray Place EH3 EDINBURGH 16 Moray 6DT scale 1 : 250@A1 SW SW - - in size. Plant area upated in A Watercore. A in upated in size. Plant area tank B. to under Stair added H3. added
FOR PLANNING CDA CDA - - FOR INFORMATION - and all relevant drawing informationand all relevant drawing Comprehensive Design Architects to be advised of any and site conditions thisdiscrepancies drawing between immediately 5260 5260 internal job no job internal E1911 dwg no www.cda 1111 225 0131 T: client key plan title project BREWERY, OLD BRISTOL drawing title SITE WIDE PROPOSED GROUND FLOOR PLAN date 18.09.19 status S2 no job internal E1911 dwg no P5 16.12.19Comercial unit updated. J1 reduced park Car layout P4P3 15.10.19 Issued for PlanningP2 08.10.19 Issued for InformationP1 04.10.19 Issued for Information 18.09.19 Issued for Information SD CG JC SH SH JC SH CM Comprehensive Design Architects 16 Moray Place Edinburgh EH3 6DT 16 Moray Notes Rev Date Description drawn chkd 1. Do not scale off this drawing in to be read conjun 2. Drawing to check3. Contractor all dimensions on site stated otherwise unless millimeters in are Dimensions 4. Registered Office: Comprehensive Design Architects Limited Registered in Scotland: SC311114 © Comprehensive Design Architects Ltd. Allrights reserved (DESIGN AND MANAGEMENT) CONSTRUCTION 2015 REGULATIONS is in to be read This conjunction drawing CDA's with and Risk Hazard AssessmentStandard ofarchitectural matters (CDM) series drawings. Works the out into be carried Construction accordance with the Principal by Contractor. Phase plan prepared 20m
T E E R
T use B1/A1/A3/A4/C1 S H (K2)
T 95 m²
R 1,025 ft² O N 10m Commercial Space B1/A1/A3/A4/C1 use B1/A1/A3/A4/C1 5m (K1) 195 m² 2,103 ft² Commercial Space 0 Northern Northern Courtyard
S N I S Alterations to vehicle access from to Street North provide vehicle crossover A E M C Entrance to Cycle Street use B1 Entrance to Building A and retained Existing wall boundary asreconstructed required C A
'Street'
Existing facades Cycle Street Cycle 140L 140L 15 16 (e) Cycle Parking 17 (H2) 70 m² 753 ft² Bins 1100L 1100L 1100L 1100L 18.4 m² 197.85 ft² 'Street' (e) Cycle Parking 18 360L Plant 5.9 m² Commercial Space 360L Plant (J1) 10.8 m² 13.0 m² 162 m² 240L 116.69 ft² B1 use B1 1,742 ft² Generator 240L 19 (H4) Commercial Space 135 m² 1,458 ft² Plant 6.2 m² 8.9 m² Comms 95.8 ft² 66.64 ft² (e) 20 Bin Store Bin Commercial Space (e) (e) 10 11 12 13 14 21 22 23 24 25 26 (H1) 383 m² 4,121 ft² 89 Commercial Space 7 UP Existing kerb raised dropped to provide levelpedestrian pathway Courtyard 37 36 35 34 33 32 31 30 29 28 27 6 38 point for 2 no. vehicles 39 (e) denotes electric(e) vehicle charging 345 1100L 1100L 1100L 1100L 1100L 40 140L 140L 46 Bins 2 31.2 m² 41 1100L 335.35 ft² 360L 360L 360L 240L 240L 240L 240L 140L 1 47 B1 use B1 42 PrivatePark Car (G1)
231 m²
2,484 ft² Control Point Control 45 44 43 Commercial Space 16 m² 171 ft² Cycle Parking
Commercial Plant Room Plant 18 m² ACCESS 13.4 m² 190 ft² 143.81 ft² Substation
Plant ACCESS 57.0 m² 28.6 m² 613.54 ft² Water Tank
B1 use B1
BAYNTON ROAD ACCESS D
Accessfor maintenance
A
O
R
Entrance to Building B
ON
T H 0-02 0-01
3B5P 3B5P
46 m² 44 m² S A Widening of footpath to be implemented as of part S278 agreement
T
E
E
R
T
S
D
R
O
F
N
R
U
D
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Appendix B BGS Radon Report
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
GeoReports
Radon Report Advisory report on the requirement for radon protective measures in new buildings, conversions and extensions to existing buildings. The report also indicates whether a site is located within a radon Affected Area
Report Id: BGS_316164/20845
Client reference: 602709-00
GeoReports
Search location
. Contains OS data © Crown Copyright and database right 2021. OS OpenMap Local: Scale: 1:5 000 (1cm = 50 m) Search location indicated in red
Site Address: CROSSFIT FORT ASHTON BAYNTON ROAD BRISTOL BS3 2EB
Area centred at: grid reference obtained from Ordnance Survey AddressPoint"] Radius of site area: 150 metres
Date: 08 April 2021 Page: 2 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
Radon Report: UK
When extensions are made to existing buildings in high radon areas, or new buildings are constructed in these areas, the Building Regulations for England, Wales, Scotland and Northern Ireland require that protective measures are taken against radon entering the building.
This report provides information on whether radon protective measures are required. Depending on the probability of buildings having high radon levels, the Regulations may require either: 1. No protective measures 2. Basic protective measures 3. Full protective measures This is an advisory report on the requirement for radon protective measures in new buildings, conversions and extensions. The report also indicates whether a site is located within a radon Affected Area
Requirement for radon protective measures
The determination below follows advice in BR211 Radon: Guidance on protective measures for new buildings (2015 edition), which also provides guidance on what to do if the result indicates that protective measures are required.
Is the property in an area where radon protective measures are required for new buildings or extensions to existing ones as described in publication BR211 (2015 edition) Radon: Guidance on protective measures for new buildings?
BASIC RADON PROTECTIVE MEASURES ARE REQUIRED FOR THE REPORT AREA.
More details of the protective measures required are available in BR211 Radon: Guidance on protective measures for new buildings (2015 Edition). Additional information and guidance is available from the Building Research Establishment website (http://www.bre.co.uk/radon/).
Whether or not the radon level in a building is above or below the radon Action Level can only be established by having the building tested. The PHE provides a radon testing service which can be accessed at www.ukradon.org or by telephone (01235 822622).
If you require further information or guidance, you should contact your local authority building control officer or approved inspector.
Date: 08 April 2021 Page: 3 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
Radon Affected Area % Homes estimated to be at or above the action level 0-1 % 1-3 % 3-5 % 5-10 % 10-30 % 30-100 %
. Contains OS data © Crown Copyright and database right 2021 Scale: 1:10 000 (1cm = 100 m) Search area indicated in red
Is the property in a radon Affected Area as defined by Public Health England (PHE) and if so what percentage of homes are estimated to be above the Action Level? YES
Additional Information
THE PROPERTY IS IN A RADON AFFECTED AREA WHERE 3 TO 5% OF HOMES ARE ESTIMATED TO BE AT OR ABOVE THE ACTION LEVEL.
PHE recommends a radon 'Action Level' of 200 Becquerels per cubic metre of air (Bq m-3) for the annual average of the radon gas concentration in a home. Where 1% or more of homes are estimated to exceed the Action Level the area should be regarded as a radon Affected Area.
This report informs you whether the property is in a radon Affected Area and the percentage of homes that are estimated to be at or above the radon Action Level at this location. Being in an Affected Area does not necessarily mean there is a radon problem in the property; the only way to find out whether the radon level is above or below the Action Level is to carry out a radon measurement.
Date: 08 April 2021 Page: 4 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
PHE advises that radon gas should be measured in all properties within radon Affected Areas and that homes with radon levels above the Action Level (200 Bq m-3) should be remediated. Householders with levels between the Target Level (100 Bq m-3) and Action Level should seriously consider reducing their radon level, especially if they are at greater risk, such as if they are current or ex smokers. Whether or not a home is in fact above or below the Action Level or Target Level can only be established by having the building tested. PHE provides a validated radon testing service which can be accessed at www.ukradon.org.
The information in this report provides an answer to one of the standard legal enquiries on house purchase in England and Wales, known as Law Society CON29 Enquiries of the Local Authority (2016); 3.14 Radon Gas: Do records indicate that the property is in a “Radon Affected Area” as identified by PHE. The data can also be used to advise house buyers and sellers in Scotland and Northern Ireland.
If you are buying a new build property in a Radon Affected Area, you should ask the builder whether radon protective measures were incorporated in the construction of the property.
If you are buying a currently occupied property in a radon Affected Area, you should ask the present owner whether radon levels have been measured in the property. If they have, ask whether the results were above the radon Action Level and if so, whether remedial measures were installed, radon levels were re-tested, and if the results of re-testing confirmed the effectiveness of the measures.
Further information on radon is available from PHE at www.ukradon.org. What is radon?
Radon is a naturally occurring radioactive gas, which is produced by the radioactive decay of radium which, in turn, is derived from the radioactive decay of uranium. Uranium is found in small quantities in all soils and rocks, although the amount varies from place to place. Radon released from rocks and soils is quickly diluted in the atmosphere. Concentrations in the open air are normally very low and do not present a hazard. Radon that enters enclosed spaces such as some buildings (particularly basements), caves, mines, and tunnels may reach high concentrations in some circumstances. The construction method and degree of ventilation will influence radon levels in individual buildings. A person’s exposure to radon will also vary according to how particular buildings and spaces are used. Inhalation of the radioactive decay products of radon gas increases the chance of developing lung cancer. If individuals are exposed to high concentrations for significant periods of time, there may be cause for concern. In order to limit the risk to individuals, the Government has adopted an Action Level for radon in homes of 200 becquerels per cubic metre (Bq m-3). The Government advises householders that, where the radon level exceeds the Action Level, measures should be taken to reduce the concentration.
Date: 08 April 2021 Page: 5 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
Radon in workplaces
The Ionising Radiation Regulations, 1999, require employers to take action when radon is present above a defined level in the workplace. Advice may be obtained from your local Health and Safety Executive Area Office or the Environmental Health Department of your local authority. The BRE publishes a guide (BR293): Radon in the workplace. BRE publications may be obtained from the BRE Bookshop, Tel: 01923 664262, email: [email protected]: www.brebookshop.com Contact Details
Keyworth Office British Geological Survey Environmental Science Centre Nicker Hill Keyworth Nottingham NG12 5GG Tel: 0115 9363143 Email: [email protected]
Wallingford Office British Geological Survey Maclean Building Wallingford Oxford OX10 8BB Tel: 01491 838800 Email: [email protected]
Edinburgh Office British Geological Survey Lyell Centre Research Avenue South Edinburgh EH14 4AP Tel: 0131 6671000 Email: [email protected]
Date: 08 April 2021 Page: 6 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
Terms and Conditions
General Terms & Conditions This Report is supplied in accordance with the GeoReports Terms & Conditions available on the BGS website at https://shop.bgs.ac.uk/georeports and also available from the BGS Enquiry Service at the above address.
Important notes about this Report • The data, information and related records supplied in this Report by BGS can only be indicative and should not be taken as a substitute for specialist interpretations, professional advice and/or detailed site investigations. You must seek professional advice before making technical interpretations on the basis of the materials provided. • Geological observations and interpretations are made according to the prevailing understanding of the subject at the time. The quality of such observations and interpretations may be affected by the availability of new data, by subsequent advances in knowledge, improved methods of interpretation, and better access to sampling locations. • Raw data may have been transcribed from analogue to digital format, or may have been acquired by means of automated measuring techniques. Although such processes are subjected to quality control to ensure reliability where possible, some raw data may have been processed without human intervention and may in consequence contain undetected errors. • Detail, which is clearly defined and accurately depicted on large-scale maps, may be lost when small-scale maps are derived from them. • Although samples and records are maintained with all reasonable care, there may be some deterioration in the long term. • The most appropriate techniques for copying original records are used, but there may be some loss of detail and dimensional distortion when such records are copied. • Data may be compiled from the disparate sources of information at BGS's disposal, including material donated to BGS by third parties, and may not originally have been subject to any verification or other quality control process. • Data, information and related records, which have been donated to BGS, have been produced for a specific purpose, and that may affect the type and completeness of the data recorded and any interpretation. The nature and purpose of data collection, and the age of the resultant material may render it unsuitable for certain applications/uses. You must verify the suitability of the material for your intended usage. • If a report or other output is produced for you on the basis of data you have provided to BGS, or your own data input into a BGS system, please do not rely on it as a source of information about other areas or geological features, as the report may omit important details. • The topography shown on any map extracts is based on the latest OS mapping and is not necessarily the same as that used in the original compilation of the BGS geological map, and to which the geological linework available at that time was fitted. • Note that for some sites, the latest available records may be historical in nature, and while every effort is made to place the analysis in a modern geological context, it is possible in some cases that the detailed geology at a site may differ from that described.
Copyright: Copyright in materials derived from the British Geological Survey's work, is owned by UK Research and Innovation (UKRI) and/ or the authority that commissioned the work. You may not copy or adapt this publication, or provide it to a third party, without first obtaining UKRI’s permission, but if you are a consultant purchasing this report solely for the purpose of providing advice to your own individual client you may incorporate it unaltered into your report to that client without further permission, provided you give a full acknowledgement of the source. Please contact the BGS Copyright Manager, British Geological Survey, Environmental Science Centre, Nicker Hill, Keyworth, Nottingham NG12 5GG. Telephone: 0115 936 3100. © UKRI 2021 All rights reserved. This product includes mapping data licensed from the Ordnance Survey® with the permission of the Controller of Her Majesty’s Stationery Office. © Crown Copyright 2021. All rights reserved. Licence number 100021290 EUL
Report issued by
Date: 08 April 2021 Page: 7 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845 GeoReports
BGS Enquiry Service
Date: 08 April 2021 Page: 8 of 8 © UKRI, 2021. All rights reserved. BGS Report No: BGS_316164/20845
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Appendix C Tier 1 Soil Assessment
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
Arup CLEA v1.071 GACs Sample No. 890163 890164 890168 890169 890170 890188 890190 890191 890192 890198 890199 890200 890202 890204 890205 890206 Exceedances Sample Ref. BH01 BH01 TP02 TP03 TP03 BH04 TP04 TP05 TP05 BH06 BH06 BH07 TP08 TP12 TP10 TP10 Commercial: Depth 0.6 1.2 0.5 0.2 0.7 0.2 0.2 0.2 0.7 0.5 1.5 1 0.2 0.5 0.3 1.3 Residential without plant uptake: Stratum MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG
Strong Evidence of hydrocarbon contamination odour, Residential without No. of homegrown No. of Analytical Parameter Units Limit of Detection Acredditation Status Commercial Exceedances produce Exceedances
Stone Content % 0.1 None <0.1 <0.1 < 0.1 < 0.1 < 0.1 14 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 Moisture Content % N/A None 7.30 13.00 23 29 30 16 3.5 7 25 14 29 27 14 8.9 17 15 Total mass of sample received kg 0.001 None 1.70 1.60 1.6 1 1 1.2 1.3 1.4 1.1 1.6 1.3 1.7 1.7 1.6 0.95 0.98 Asbestos in Soil Screen / Identification Name Type N/A ISO 17025 Asbestos in Soil Type N/A ISO 17025 Not-detected Not-detected Not-detected Not-detected Not-detectedNot-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Asbestos Quantification (Stage 2) % 0.001 ISO 17025 Asbestos Quantification Total % 0.001 ISO 17025 Asbestos Quantification - PCM (low level) % 0.0001 ISO 17025 Asbestos Quantification - Total (low level) % 0.0001 ISO 17025 General Inorganics pH - Automated pH Units N/A MCERTS 20.00 7.90 8.10 10.4 8.4 8.2 8.4 12.2 8.7 9 8.3 7.8 8.2 11.7 10.6 9.1 9 Free Cyanide mg/kg 1 MCERTS < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1.0 < 1.0 < 1.0 Water Soluble SO4 16hr extraction (2:1 Leachate Equivalent) g/l 0.00125 MCERTS 0.26 0.21 0.17 0.062 0.045 0.062 0.0058 0.029 0.13 0.035 0.29 0.036 0.04 0.16 0.07 0.16 Fraction Organic Carbon (FOC) N/A 0.001 NONE 0.074 0.040 0.026 0.017 0.015 0.0071 < 0.0010 0.013 0.055 0.02 0.066 0.023 0.012 0.012 0.059 0.059 Total Phenols Total Phenols mg/kg 1 MCERTS < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 1.1 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 Speciated PAHs Naphthalene mg/kg 0.05 MCERTS 193.00 0 2.33 2 1.2 0.73 0.19 0.16 0.16 < 0.05 < 0.05 < 0.05 0.41 < 0.05 2.90 < 0.05 0.47 < 0.05 0.18 0.23 Acenaphthylene mg/kg 0.05 MCERTS 83200.00 0 2893.27 0 < 0.05 < 0.05 0.13 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 0.14 0.4 Acenaphthene mg/kg 0.05 MCERTS 83700.00 0 2995.03 0 < 0.05 < 0.05 0.18 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 0.23 < 0.05 1.1 < 0.05 < 0.05 < 0.05 0.4 1.1 Fluorene mg/kg 0.05 MCERTS 63000.00 0 2794.85 0 < 0.05 < 0.05 0.18 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 0.21 < 0.05 1.4 < 0.05 < 0.05 < 0.05 0.42 1.1 Phenanthrene mg/kg 0.05 MCERTS 21900.00 0 1291.72 0 1.5 1.2 3.2 0.21 0.27 < 0.05 < 0.05 < 0.05 2.1 < 0.05 2.4 < 0.05 1.2 1.3 3.4 13 Anthracene mg/kg 0.05 MCERTS 523000.00 0 30603.88 0 < 0.05 0.34 0.54 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 0.35 < 0.05 0.43 < 0.05 0.27 0.34 0.97 4.3 Fluoranthene mg/kg 0.05 MCERTS 22600.00 0 1526.40 0 1.2 2.9 5.9 0.48 0.52 < 0.05 < 0.05 < 0.05 3.5 < 0.05 0.56 < 0.05 1.1 2 6.5 33 Pyrene mg/kg 0.05 MCERTS 54200.00 0 3661.13 0 1.2 2.7 5 0.4 0.5 < 0.05 < 0.05 < 0.05 3 < 0.05 0.8 < 0.05 0.94 1.7 5.7 27 Benzo[a]anthracene mg/kg 0.05 MCERTS 167.00 0 10.97 4 0.94 2.7 3.2 0.38 0.47 < 0.05 < 0.05 < 0.05 2.1 < 0.05 < 0.05 < 0.05 0.62 1.2 3.7 17 Chrysene mg/kg 0.05 MCERTS 346.00 0 29.66 3 1.1 2.3 2.6 0.34 0.47 < 0.05 < 0.05 < 0.05 2.1 < 0.05 < 0.05 < 0.05 0.63 0.9 3.3 14 Benzo[b]fluoranthene mg/kg 0.05 MCERTS 44.30 3 3.95 9 1.5 4.1 3.4 0.45 0.57 < 0.05 < 0.05 < 0.05 2.7 < 0.05 < 0.05 < 0.05 0.65 1.4 5 22 Benzo[k]fluoranthene mg/kg 0.05 MCERTS 1170.00 0 105.64 0 0.45 1.4 1.9 0.19 0.21 < 0.05 < 0.05 < 0.05 1.2 < 0.05 < 0.05 < 0.05 0.28 0.63 1.3 6 Benzo[a]pyrene (C4SL for RWPU) mg/kg 0.05 MCERTS 35.20 3 5.30 7 1.2 3.7 2.8 0.33 0.41 < 0.05 < 0.05 < 0.05 2.4 < 0.05 < 0.05 < 0.05 0.53 1.1 3.5 15 Indeno[123-cd]pyrene mg/kg 0.05 MCERTS 501.00 0 45.00 0 0.7 2.4 1.4 0.16 0.18 < 0.05 < 0.05 < 0.05 1.3 < 0.05 < 0.05 < 0.05 < 0.05 0.63 1.6 7.6 Dibenz[ah]anthracene mg/kg 0.05 MCERTS 3.53 3 0.31 11 0.2 0.63 0.31 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 0.3 < 0.05 < 0.05 < 0.05 < 0.05 0.15 0.46 2.1 Benzo[ghi]perylene mg/kg 0.05 MCERTS 3930.00 0 355.14 0 0.76 2.2 1.6 0.18 0.22 < 0.05 < 0.05 < 0.05 1.2 < 0.05 < 0.05 < 0.05 < 0.05 0.73 1.9 8 Total PAH Speciated Total EPA-16 PAHs mg/kg 0.8 MCERTS #N/A 0 #N/A 0 12.00 27.20 32.3 3.28 3.98 < 0.80 < 0.80 < 0.80 23.1 < 0.80 9.71 < 0.80 6.65 12.1 38.5 173 Heavy Metals / Metalloids Arsenic C4SL mg/kg 1 MCERTS 640.00 0 40.00 0 13.00 20.00 19 20 20 24 7.7 10 32 9.7 20 18 15 24 8.3 9.8 Beryllium mg/kg 0.06 MCERTS 11.70 0 1.72 7 0.95 1.10 1.2 1.8 1.8 0.67 0.33 0.19 4 1.8 1.6 1.1 1.6 0.94 3 2.4 Boron mg/kg 0.2 MCERTS 236000.00 0 10775.16 0 3.40 3.80 1.4 4.9 4.7 1.4 2.5 1.1 3 0.9 7.4 1.5 11 1.4 1.2 1.2 Cadmium C4SL mg/kg 0.2 MCERTS 410.00 0 150.00 0 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 1.1 0.2 0.6 1 0.3 0.7 < 0.2 0.4 1.9 < 0.2 0.4 Chromium (VI) mg/kg 1.2 MCERTS 32.80 0 6.00 0 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 Chromium (IV) C4SL mg/kg 1 MCERTS 8570.00 0 907.00 0 6.90 21.00 16 48 46 20 9.6 12 25 13 15 20 13 13 12 14 Copper mg/kg 1 MCERTS 68300.00 0 7130.00 1 47.00 47.00 180 40 34 14 12 24 110 52 86 58 68 16000 69 55 Lead C4SL mg/kg 1 MCERTS 2300.00 0 310.00 7 51.00 48.00 380 140 100 56 21 41 320 54 160 110 80 900 52 88 Mercury (Inorganic) mg/kg 0.3 MCERTS 1120.00 0 56.00 0 0.30 < 0.3 0.8 < 0.3 < 0.3 < 0.3 < 0.3 < 0.3 0.9 < 0.3 0.6 0.6 < 0.3 < 0.3 < 0.3 < 0.3 Nickel mg/kg 1 MCERTS 983.00 0 181.40 0 34.00 31.00 22 35 34 13 5.9 7.1 41 31 26 20 20 33 50 40 Selenium mg/kg 1 MCERTS 12261.00 0 430.00 0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 Vanadium mg/kg 1 MCERTS 6360.00 0 651.17 0 12.00 25.00 21 53 54 21 10 8.1 33 20 25 28 23 23 35 32 Zinc mg/kg 1 MCERTS 730000.00 0 40400.00 0 83.00 120.00 260 160 120 120 37 120 310 48 130 98 130 1900 92 100 Monoaromatics Benzene (C4SL for RWPU) ug/kg 1 MCERTS 26597.88 0 890.00 0 < 1.0 < 1.0 Toluene ug/kg 1 MCERTS 56293712.79 0 880000.00 0 < 1.0 < 1.0 Ethylbenzene ug/kg 1 MCERTS 5705504.84 0 82400.00 0 < 1.0 < 1.0 p & m-xylene ug/kg 1 MCERTS 5923263 0 79000 0 < 1.0 < 1.0 o-Xylene ug/kg 1 MCERTS 6603100.73 0 88300.00 0 < 1.0 < 1.0 MTBE (Methyl Tertiary Butyl Ether) ug/kg 1 MCERTS 5705505 0 378.00 0 < 1.0 < 1.0 Petroleum Hydrocarbons TPH - Aliphatic EC5-EC6 mg/kg 0.001 MCERTS 3190.00 0 42.42 0 < 0.001 < 0.001 TPH - Aliphatic >EC6-EC8 mg/kg 0.001 MCERTS 7780.00 0 103.56 0 < 0.001 < 0.001 TPH - Aliphatic >EC8-EC10 mg/kg 0.001 MCERTS 2000.00 0 26.81 0 < 0.001 2.2 TPH - Aliphatic >EC10-EC12 mg/kg 1 MCERTS 9690.00 0 132.32 0 < 1.0 23 TPH - Aliphatic >EC12-EC16 mg/kg 2 MCERTS 58800.00 0 1060.82 0 < 2.0 630 Aliphatic >EC16 - EC21 mg/kg 8 MCERTS 648000.00 0 11924.63 0 < 8.0 1200 Aliphatic >EC21 - EC35 mg/kg 8 MCERTS 648000.00 0 11924.63 0 < 8.0 2300 Aliphatic >EC16 - EC35 mg/kg 10 MCERTS 648000.00 0 11924.63 0 < 10 3500 TPH - Aliphatic >EC35-EC44 mg/kg 8.4 NONE 648000.00 0 11924.63 0 < 8.4 590 0 0 TPH - Aromatic >EC5-EC7 (benzene) mg/kg 0.001 MCERTS 27.00 0 0.38 0 < 0.001 < 0.001 TPH - Aromatic >EC7-EC8 (toluene) mg/kg 0.001 MCERTS 56293.71 0 880.00 0 < 0.001 < 0.001 TPH - Aromatic >EC8-EC10 mg/kg 0.001 MCERTS 3460.00 0 47.20 0 < 0.001 < 0.001 TPH - Aromatic >EC10-EC12 mg/kg 1 MCERTS 16200.00 0 251.73 0 < 1.0 34 TPH - Aromatic >EC12-EC16 mg/kg 2 MCERTS 36200.00 0 1800.00 0 < 2.0 600 TPH - Aromatic >EC16-EC21 mg/kg 10 MCERTS 26600.00 0 1400.00 0 < 10 1200 TPH - Aromatic >EC35-EC44 mg/kg 8.4 NONE 28400.00 0 1930.00 0 < 8.4 99 890207 892297 892513 892514 892515 892516 893580 893581 893626 893627 893628 893629 893630 893715 893720 893721 893722 893742 918738 918739 918740 918741 918742 918743 918744 918745 918746 890189 890203 890201 TP15 BH01A BH03 BH03 BH05 BH05 BH01 TP13 TP06 TP06 TP06 TP06A TP06B BH02 TP09 TP01A TP16 TP10A BH03 BH03 BH03 BH04 BH05 TP04 TP08 TP10 TP12 BH04 TP08 BH07 0.5 1.5 0.8 1.6 0.3 1 0.25 0.5 0.2 0.5 0.7 0.2 0.4 0.5 0.6 0.5 0.5 1.55 0.3 1.2 1.6 0.2 1.6 0.5 0.2 1.3 0.5 0.5 0.7 1.5
MG MG MG MG MG MH MG MG MH MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG MG ALU ALU ALU
Hydrocarbon Hydrocarbon Asbestos sheeting odour, oily odour identified sheen
< 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 32 < 0.1 52 < 0.1 19 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 9.2 < 0.1 15 7.4 8.2 < 0.1 < 0.2 < 0.3 < 0.4 < 0.1 < 0.1 < 0.1 8 22 21 25 15 15 5.7 14 6.9 6.1 12 25 21 26 18 26 4.5 23 25 13 6.2 25 9.1 2.8 9.6 30 30 37 1.3 1.1 1.5 1.2 1.5 1.8 1.9 1.6 1.8 1.7 1.6 1.6 2 1.5 1.5 1.6 1.4 1.2 1.4 1.6 1.3 1.4 1.1 0.91 1.2 1.1 1.3 1.2 Chrysotile Amosite Chrysotile Chrysotile & Amosite Not-detected Not-detected DetectedNot-detected Not-detected Not-detectedNot-detected Not-detected Detected Detected Detected Not-detected Not-detectedNot-detectedNot-detected Not-detectedNot-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected Not-detected < 0.001 < 0.001 0.015 0.001 < 0.001 < 0.001 < 0.0001 < 0.0001 0.0152 0.001
11.6 6.9 7.8 7.8 7.8 8 7.6 11 8.2 10 10.9 9.9 11.6 9.1 9.9 8.1 8 7.6 7.8 8.2 8.3 8.1 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1.0 < 1 0.057 0.13 0.023 0.033 0.048 0.029 0.045 1.9 0.023 0.17 0.18 0.14 0.11 0.16 0.66 0.19 0.019 0.068 0.086 0.2 0.06 0.41 0.023 0.051 0.048 0.055 0.016 0.011 0.029 0.02 0.027 0.006 0.034 0.03 0.015 0.042 0.022 0.043 0.0026 0.04 0.033 0.026 0.011 0.042
< 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0
2.30 1.00 0.70 0.18 < 0.05 < 0.05 0.73 < 0.05 < 0.05 < 0.05 5.50 0.40 < 0.05 < 0.05 < 0.05 1.30 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 2.5 0.24 0.27 < 0.05 < 0.05 < 0.05 0.25 < 0.05 0.75 < 0.05 1.2 0.32 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 6 2.5 0.63 < 0.05 < 0.05 < 0.05 0.11 < 0.05 5.8 < 0.05 7.7 0.31 < 0.05 < 0.05 < 0.05 < 0.05 0.68 < 0.05 0.17 < 0.05 < 0.05 < 0.05 9.1 2 0.57 < 0.05 < 0.05 < 0.05 0.21 < 0.05 5.2 < 0.05 8.5 0.19 < 0.05 < 0.05 < 0.05 < 0.05 0.57 0.25 0.27 < 0.05 < 0.05 < 0.05 64 17 7.1 1.9 0.33 1.4 3.3 0.52 91 1.5 100 5.4 < 0.05 0.52 0.36 1.4 4.8 2.5 3.1 < 0.05 < 0.05 < 0.05 20 4.5 1.7 0.32 < 0.05 0.33 0.6 < 0.05 23 0.45 28 1.5 < 0.05 < 0.05 < 0.05 < 0.05 1.1 0.6 0.52 < 0.05 < 0.05 < 0.05 77 17 11 2.9 0.47 3.2 7.3 0.5 120 4 160 13 < 0.05 0.5 0.3 1.2 5.6 3.6 3.1 < 0.05 < 0.05 < 0.05 76 14 10 2.5 0.42 3 6.4 0.42 79 3.4 140 10 < 0.05 0.45 0.26 1.3 4.8 3.1 2.8 < 0.05 < 0.05 < 0.05 55 8.5 6.3 2.1 0.28 1.5 3.8 0.29 46 2.3 87 8.7 < 0.05 0.35 0.2 0.54 2 1.7 1.1 < 0.05 < 0.05 < 0.05 37 7.2 5.3 1.9 0.28 1.5 2.5 0.25 42 1.8 78 7.6 < 0.05 0.36 0.24 0.42 1.9 1.9 1.3 < 0.05 < 0.05 < 0.05 55 6.6 5.7 1.8 0.32 1.8 3.5 0.27 47 3 99 10 < 0.05 0.36 0.2 0.56 2.6 1.9 1.2 < 0.05 < 0.05 < 0.05 19 6.5 5 1 0.26 1.2 2.3 0.15 27 1.2 41 6.1 < 0.05 0.28 0.13 0.5 0.8 1.3 0.76 < 0.05 < 0.05 < 0.05 47 8.5 7.3 1.6 0.3 1.9 3.5 0.27 39 2.4 88 11 < 0.05 0.39 0.23 0.58 2.3 1.9 1.2 < 0.05 < 0.05 < 0.05 20 4 3.5 0.74 0.15 0.91 2.1 < 0.05 20 1.4 36 7.7 < 0.05 < 0.05 < 0.05 0.35 1.1 1 0.53 < 0.05 < 0.05 < 0.05 4.7 0.88 0.81 0.18 < 0.05 < 0.05 0.52 < 0.05 5.3 0.46 11 2.3 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 22 4.4 4.8 0.85 0.21 1.3 2.2 < 0.05 21 1.7 42 9.4 < 0.05 < 0.05 < 0.05 0.45 1.2 1.2 0.6 < 0.05 < 0.05 < 0.05
516 105 71.1 18 3.02 17.9 39.3 2.67 569 23.5 936 93.9 < 0.80 3.21 1.92 8.55 29.5 21 16.6 < 0.80 < 0.80 < 0.80
11 16 22 33 12 17 8.6 12 17 11 36 24 8.9 25 17 15 15 18 6.9 14 13 14 0.46 1.5 1.7 1.4 0.74 0.88 0.63 0.82 0.2 0.12 0.73 1.3 0.5 1.6 2.1 1.1 0.21 1.2 0.95 1.5 1.6 0.8 2.9 4.7 1.7 2.5 1.9 0.9 2.7 6.4 0.8 1.2 2 2.1 1 3.7 3 4.3 0.9 2.4 3.3 4.6 3.8 4.2 0.7 < 0.2 2 < 0.2 0.8 0.9 0.6 < 0.2 1.1 0.6 < 0.2 0.8 < 0.2 < 0.2 < 0.2 0.4 0.8 0.5 < 0.2 < 0.2 < 0.2 0.5 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 < 1.2 13 22 19 32 21 22 7.8 16 9.1 8.3 16 16 12 21 24 17 5.9 23 8 36 43 17 71 73 140 94 44 77 33 220 41 20 58 110 33 100 73 65 8.2 66 44 23 68 59 89 140 250 2100 100 140 40 530 120 42 220 500 67 240 150 150 38 740 33 53 48 130 < 0.3 2.2 1.4 21 0.4 0.4 < 0.3 < 0.3 0.5 0.3 0.8 1 0.3 0.9 < 0.3 0.5 < 0.3 9.3 < 0.3 < 0.3 < 0.3 0.7 12 48 31 37 14 16 21 25 8.4 6.2 21 24 9.7 29 35 23 4 2.6 35 32 27 16 < 1.0 2.1 1.1 1.2 < 1.0 < 1.0 1.2 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 1.1 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 19 28 32 34 21 26 11 22 9.7 9.1 21 26 14 29 38 22 11 40 15 39 46 21 130 200 400 1100 180 290 80 64 150 84 170 170 71 150 310 110 75 560 100 100 120 94
< 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0
< 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 1.3 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 1.0 30 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 2.3 < 2.0 500 < 2.0 < 2.0 2 < 2.0 2.5 17 < 8.0 700 < 8.0 < 8.0 < 8.0 < 8.0 < 8.0 54 < 8.0 920 < 8.0 < 8.0 12 < 8.0 34 62 < 10 1600 < 10 < 10 12 < 10 34 120 < 8.4 390 < 8.4 < 8.4 < 8.4 < 8.4 12 15
< 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 0.001 < 1.0 24 < 1.0 < 1.0 < 1.0 < 1.0 1.9 1.3 < 2.0 360 2.3 5 2.1 5.7 18 11 12 500 12 25 26 64 210 75 < 8.4 220 < 8.4 11 < 8.4 18 170 28
McLaughlin & Harvey Old Brewery, Ashton Remediation Implementation and Verification Plan
Appendix D Arup GAC Derivation
REP/004/21 | Issue | 16 April 2021 \\GLOBAL\EUROPE\BRISTOL\JOBS\271XXX\271182-00\4.50_REPORTS\4.52 GEO\RIVP\2021-04-16_RIVP_BRISTOLBREWERY_ISSUE.DOCX
Generic assessment criteria (GAC)
Generic assessment criteria (GAC) and Category 4 screening levels (C4SL) have been used as initial screening tool to assess whether further action may be necessary to mitigate an identified pollutant linkage, based on the results of the investigation of the potential sources and plausible pollutant linkages identified by the conceptual model. Where all reported sample concentrations are below the screening values and the site complies with the assumptions behind the assessment criteria, then it can be regarded as suitable for use without remediation. If the results exceed the screening assessment criteria then either further detailed assessment is provided or recommendations for mitigation such as risk management procedures and remediation have been provided. GAC values have been calculated using the Contaminated Land Exposure Assessment (CLEA) model software (v1.07) developed by the Environment Agency and published in 2015. The model estimates human exposure to soil contaminants for those potentially living, working and/or playing on contaminated sites over long time periods (chronic exposure). The CLEA model does not include short-term (acute) risks to humans or risks from groundwater to humans. The CLEA model includes the following generic land uses, for which GAC can be developed by the user: • Residential development including homegrown produce consumption (assumed to be from private gardens within the development) • Residential development without homegrown produce consumption • Allotments • Commercial • POSresi Public Open Space forming part of a residential development • POSpark Public Open Space park Soil organic matter content can influence the retention and transport of organic contaminants in soils and generic criteria have been developed for soil organic matter content of 1, 2.5 and 6%. This is in line with UK guidelines. The soil testing results have been compared to generic screening criteria based on the proposed land use at the site and conservative organic matter content assumptions. Chemical, physical and toxicological data sources Data published by the Environment Agency for CLEA Full toxicological and physical/chemical data has been published by the Environment Agency for eleven chemicals. The data for these chemicals is embedded within the CLEA v1.07 software. In addition, physical/chemical data for selected organic pollutants for use in environmental risk assessment has been published by the Environment Agency1,2 which has been used where available. Category 4 Screening Levels and Lead The revised Statutory Contaminated Land Guidance published in April 20123 presented a new “four category system” for considering land under Part 2A. This ranged from Category 4, where there is no risk that land poses a significant possibility of significant harm (SPOSH), to Category 1, where the risk that land poses SPOSH is unacceptably high. The Statutory Guidance stated that “new technical tools and advice may be developed and used.... to help regulators and others conform to this Guidance.” To support this, Defra funded a research project to deliver: • A methodology for deriving C4SLs for five generic land-uses comprising residential, commercial, allotments and public open space (park and residential); and • A demonstration of the methodology, via the derivation of C4Sls for six substances: arsenic, benzene, benzo(a)pyrene, cadmium, chromium (VI) and lead. The output of this research has been published as a Final Project Report with appendices detailing the individual contaminants and a Defra Policy Companion Document4. C4SLs “are designed to reflect a more pragmatic approach to contaminated land risk assessment (albeit still strongly precautionary)”. They represent a risk that is higher than “minimal” and describes land that is clearly not contaminated land. It is recognised that C4SLs were designed to support the Statutory Contaminated Land framework i.e. Part 2A assessments and were not specifically designed for use within the National Planning Policy Framework. In their Policy Companion Document4, Defra stated that C4SLs could be used in planning matters. This was later clarified in a letter from Lord de Mauley to Local Authorities5, which stated that the “Impact Assessment agreed during the revision of the Part 2A Statutory Guidance was developed on the basis that C4SLs could be used under the planning regime, as well as within Part 2A. This intent is reflected within DCLG’s Planning Practice Guidance on Land Affected by Contamination, which was revised on 12 June 2014 and now includes reference to the use of C4SLs in risk assessment under planning”. As a precautionary measure, because C4SLs do not represent “minimal risk”, Arup continues to use GACs as an initial screen and then C4SLs to further assess the risk if necessary. The exception to this is lead, for which Arup has not developed a GAC and therefore uses the C4SL for lead as a GAC in the generic screening of soil data. For several land uses, the lead C4SL is lower than the published background level for lead. As such Defra recommends a “pragmatic approach” whereby the use of the ‘normal’ background concentration is used as
1 Environment Agency (2003) Review of the Fate and Transport of Selected Contaminants in the Soil Environment. Technical Report P5-079/TR1 2 Environment Agency (2008) Compilation of data for priority organic pollutants for derivation of Soil Guideline Values. Science Report: SC050021/SR7 3 Defra (2012) Environmental Protection Act 1990: Part 2A: Contaminated Land Statutory Guidance. 4http://randd.defra.gov.uk/Default.aspx?Module=More&Location=None&ProjectID=18341 5 Defra, 3rd September 2014, Letter from Lord de Mauley, Parliamentary Under Secretary to All Local Authorities. an assessment criterion when the land-use and domain permit it, “so as not to disproportionately target land where there is widespread diffuse pollution of lead”.6 LQM/CIEH S4ULs Generic Assessment Criteria (GAC) together with supporting physical/chemical and health criteria values have been published by LQM/CIEH in the document “The LQM/CIEH S4ULs for Human Health Risk Assessment”7. Arup has critically reviewed the data within this document and generated GACs using CLEA v1.07 for the contaminants within it, using the input parameters provided in the S4UL document. In some cases, the Arup GACs differ to those generated by LQM, as a result of different exposure assumptions and input parameters being used, where Arup felt these were more appropriate or precautionary. CL:AIRE/EIC/AGS GAC In January 2010, CL:AIRE, together with the AGS and EIC, published peer-reviewed GACs for 35 contaminants, together with the supporting chemical, physical and toxicological data8 using the CLEA methodology. Arup has critically reviewed the data within this document and generated GACs using CLEA v1.07 for the contaminants within it. The Arup GACs differ to some of those generated by CL:AIRE/EIC/AGS, as a result of the use of an updated version of the CLEA software and different exposure assumptions. Exposure assumptions made in Generating Arup GACs In generating the Arup GAC, the exposure assumptions used to develop the C4SLs have been adopted in preference to those described in the Environment Agency’s SR3 publication9. These revised exposure assumptions are embedded within the CLEA v1.07 software, alongside the unmodified SR3 exposure assumptions. When reporting GAC for many organic compounds, the CLEA software does not cap exposure at the solubility or vapour saturation limits, meaning that GACs can be generated which exceed the theoretical saturation limit. Where this has occurred when generating the Arup GACs, the saturation limit has been quoted in parentheses next to the GAC. For sites where the vapour pathway will dominate the exposure in the developed condition of the site, if no other pathways are considered to be active (the soil being covered with buildings and hardstanding) and where the soil concentrations measured on site exceed the theoretical saturation limits, consideration has been given to the possibility that free product may be present. The Environment Agency advises that where the vapour pathway is the only route of exposure considered, and the resulting assessment criterion exceeds the theoretical saturation limit, exposure is unlikely to reach the relevant HCV and the risk based on the assumed conceptual model is likely to be negligible. The Arup GAC for phenol are based on the approach taken by LQM/CIEH in developing their S4ULs, namely in order to be protective of direct bodily contact with phenol- contaminated soils and account for uncertainties in the modelling, the GAC has been limited
6 Defra (2014) Development of Category 4 Screening Levels for Assessment of Land Affected by Contamination (SP1010): Policy Companion Document, March 2014 7 Copyright Land Quality Management Limited reproduced with permission; Publication number S4UL3213. All rights reserved. 8 CL:AIRE/EIC/AGS (2010) Soil Generic Assessment Criteria for Human Health Risk Assessment 9 Environment Agency (2009) Updated technical background to the CLEA model. Science Report: SC050021/SR3. to a level at which the corresponding soil solution concentration would be 1g/L (i.e. 0.1% by weight). Two GACs have therefore been derived for phenol; one set at the chronic exposure level calculated using CLEA v1.07 or the soil concentration associated with a soil solution of 0.1% by weight. Depending on the conceptual site model, either GAC could be selected. Arup GAC for chronic and acute inorganic cyanide exposure A chronic exposure GAC has been derived by Arup using the CLEA v1.07 software and toxicological information published by the Environment Agency for this contaminant in the TOX5 report10. Physical/chemical information for inorganic cyanide has been collated by Arup for the purposes of deriving a GAC. An acute exposure GAC has also been derived by Arup. The TOX 5 report notes that free and simple cyanide have a high acute toxicity and that the conceptual exposure model should be based on a single short-term exposure event, although an approved methodology for this assessment is not provided. In the absence of further guidance from the Environment Agency/DEFRA the TOX5 assumptions for toxicity have been used. A soil ingestion rate for an acute, one-off episode of pica (the exploratory, deliberate eating of soil) has been ascertained from a review of suitable reference documents. The technical support document to the CLEA model (SR3) summarises some of the literature in this area and highlights how approximately one child out of 600 children whose soil ingestion rates were studied exhibited pica behaviour at an observed ingestion rate of up to 13.6 g/day, although the same child was found to have an overall mean ingestion rate of five to six grams per day11. ATSDR assume that soil-pica children ingest 5000mg (5g) of soil per day, although an expert panel noted that this ingestion rate appeared to be supported by only a few subjects in soil ingestion studies (two children in Massachusetts and several children in Jamaica). It was agreed that ATSDR should err on the side of caution and use the 5g ingestion rate until more data had been collected.12 Based on this information, the One Time Soil Ingestion Rate (OTSIR) adopted for an acute episode of pica (the exploratory, deliberate eating of soil) is based on a one-off dose of 5g (equivalent to one teaspoon), a value which has also been used by the UK Health Protection Agency in the assessment of acute cyanide exposure13. It is noted that the Scotland and Northern Ireland Forum for Environmental Research (SNIFFER) methodology for the calculation of an acute cyanide value has now been withdrawn (2003)14. However, in the absence of further guidance the methodology described below (taken from the SNIFFER cyanide worksheet has been used to derive a numeric assessment value for short-term exposure (soil ingestion) of free cyanide. The relevant equation is: RTC = (TF BW) /OTSIR
10 Defra and the Environment Agency (2002) Contaminants in Soil: Collation of Toxicological Data and Intake Values for Humans. R&D Publication TOX5. 11 Defra and Environment Agency (2009) Updated technical background to the CLEA model. Science Report: SC050021/SR3 12 http://www.atsdr.cdc.gov/child/executive_summary.html 13 http://www.sobra.org.uk/content/presentations/Dec%202012%20conference/Yolande%20Mackin.pdf 14 SNIFFER (April 2000). Framework for Deriving Numeric Targets to Minimise the Adverse Human Health Effects of Long-term Exposure to Contaminants in Soil (Report No: SR 99(0) F). The second edition of the SNIFFER method was published in April 2003 (Report No: LQ01). where: RTC = reference target concentration (mg kg-1 bw) or Acute Generic Assessment Criteria (Acute GAC) TF = appropriate toxicological factor (mg kg-1 bw), TF = lowest published lethal dose (LDLO) /uncertainty factor (UF), or Tolerable Daily Intake (TDI) BW =- body weight (kg) OTSIR = one-time soil ingestion rate (kg soil) There is very little toxicological data on the lowest known acute dose of cyanide. Defra and the Environment Agency (2002) report a TDI of 0.012mg/kg bw/day. For a residential scenario, a female child is assumed to be the critical receptor, in line with CLEA guidance. For a one-time soil ingestion it is suggested that 9.8kg should be used as a default body weight (mean female body weight for an 18-month-old child given in SR1), given that children of this age would be expected to exhibit the type of hand-to-mouth exploratory behaviour which could lead to acute soil ingestion. There is evidence that pica behaviour has been observed in older children, but an 18-month-old is selected for the development of a GAC as a conservative measure, since the bodyweight will be lower. 5g (0.005kg) of soil has been selected as an appropriate OTSIR. The acute cyanide GAC for an 18-month-old child in a residential/allotment exposure scenario is therefore as follows: Acute cyanide GAC = (0.012 mg kg-1 bw x 9.8kg bw)/0.005 kg = 23.5 rounded to 24 mg kg- 1 For a commercial scenario, the female worker is taken to be the critical receptor in line with CLEA guidance and it is suggested that the 70kg body weight should be used (mean adult body weight SR1) and 5g (0.005kg) of soil as an appropriate OTSIR, as for the child exposure scenario. The acute cyanide GAC for an adult in a commercial exposure scenario is therefore as follows: Acute cyanide GAC = (0.012 mg kg-1 bw x 70kg bw)/0.005 kg = 168 mg kg-1 This methodology is not applicable to acute inhalation of inorganic free cyanides. It is noted that the commercial scenario criteria assumes a female worker is the critical receptor and the calculated criteria is therefore not applicable to commercial land-uses which are designed for children, this may include crèche, playground or leisure facilities. Screening protocol for asbestos Recent guidance15 confirms that the assessment of asbestos on the basis of comparison with a generic screening criterion is not appropriate. As a precautionary measure, the asbestos laboratory detection limit (0.001%) has been taken as the initial screening criterion.
15 Ciria (2014) Asbestos in soil and made ground: a guide to understanding and managing risks. Publication C733. Screening protocol where no GAC exists Some contaminants have been analysed but no GAC or other authoritative UK screening value (e.g. C4SL, SGV) exists. Where GACs have not been developed, this is usually due to a low level of confidence in the available data on the toxicity of the contaminant, to the extent that the development of a GAC using the data may not be sufficiently protective of health. Comparing chemicals against GACs for chemically similar compounds (termed “surrogates” here) can be appropriate in some cases, and is the approach commonly adopted for volatile and semi-volatile chemicals. Where volatile chemicals are present in excess of their respective laboratory limits of detection, they are considered to be of potential concern to health. Where volatile chemicals are not present above the laboratory limits of detection, they have been ruled out as potential contaminants of concern. This approach is considered to be in line with the principle of ‘As Low As Reasonably Practicable’ (ALARP), in that if the contaminants were present in significant quantity as a result of previous on-site processes, they would be capable of detection in parts per million quantities (the level of detection typically used for VOCs).