WRITTEN SCHEME OF INVESTIGATION FOR ARCHAEOLOGICAL MITIGATION DURING THE CONSTRUCTION PHASE OF BRIGHTON AND HOVE WTW/SRC INFRASTRUCTURE
RPS 1st Floor West Cottons Centre Cottons Lane London SE1 2QG
Telephone: 020 7939 8000 Facsimile: 020 7939 8098/99
RPS Ref: JLH0015
Date: February 2008 Revised July 2008
COPYRIGHT The contents of this document must not be copied or reproduced in whole or in part without the written consent of RPS Brighton and Hove Wastewater Treatment Project Infrastructure WSI
CONTENTS
Page No
SECTION 1: INTRODUCTION 1
SECTION 2: ARCHAEOLOGICAL AND TOPOGRAPHICAL BACKGROUND 3
SECTION 3: ARCHAEOLOGY SURVEY PROCEDURES 12
SECTION 4: BIBLIOGRAPHY 15
FIGURE 1: LOCATION OF INFRASTRUCTURE SITES
FIGURE 2: ARCHAEOLOGICAL SITES AND FINDS IN THE STUDY AREAS FOR
PENSTOCK SHAFT, MARINE GATE SHAFT, MARINE DRIVE
(ROEDEAN) PUMPING STATION AND ROEDEAN WAY SHAFT
FIGURE 3: ARCHAEOLOGICAL SITES AND FINDS IN THE STUDY AREAS FOR
OVINGDEAN, ROTTINGDEAN AND SALTDEAN SHAFTS
FIGURE 4: ARCHAEOLOGICAL SITES AND FINDS IN THE STUDY AREAS FOR
SALTDEAN EAST SHAFT, PORTABELLO PUMPING STATION AND
MERIDAN CAR PARK SHAFT
FIGURE 5: ARCHAEOLOGICAL SITES AND FINDS IN THE STUDY AREAS FOR
PEACEHAVEN WTW/SRC AND FRIAR’S BAY HEAD SHAFT
FIGURE 6: MARINE GATE SHAFT SITE SHOWING 2004 ARCHAEOLOGICAL
SURVEYS
FIGURE 7: MARINE DRIVE PUMPING STATION SITE SHOWING PROPOSED
TRENCHES
FIGURE 8: ROEDEAN WAY SHAFT SITE SHOWING 2004 ARCHAEOLOGICAL
SURVEYS
FIGURE 9: OVINGDEAN SHAFT SITE
FIGURE 10: ROTTINGDEAN SHAFT SITE Brighton and Hove Wastewater Treatment Project Infrastructure WSI
FIGURE 11: SALTDEAN SHAFT SITE
FIGURE 12: SALTDEAN EAST SHAFT SHOWING 2004 ARCHAEOLOGICAL
SURVEYS
FIGURE 13: PORTABELLO PUMPING STATION SITE SHOWING 2004
ARCHAEOLOGICAL SURVEYS
FIGURE 14: MERIDIAN WAY SHAFT SITE
FIGURE 15: FRIAR’S BAY (HEAD CHAMBER) SHAFT SITE SHOWING 2004 TRIAL
TRENCH
APPENDIX 1: 2006 GEOTECHNICAL INVESTIGATION RESULTS
(ARCHAEOSCAPE)
APPENDIX 2: TRIAL TRENCHING METHODOLOGY FOR MARINE DRIVE
(ROEDEAN PUMPING STATION) (RPS IN ASSOCIATION WITH
ARCHAEOLOGY SOUTH-EAST)
APPENDIX 3: WATCHING BRIEF METHODOLOGY (AFTER ARCHAEOLOGY
SOUTH-EAST)
APPENDIX 4: SPECIFICATION FOR ARCHAEOLOGICAL EXCAVATION (IF
REQUIRED) (RPS IN ASSOCIATION WITH ARCHAEOLOGY
SOUTH-EAST)
APPENDIX 5: BRIGHTON & HOVE WWTW ROUTE INFRASTRUCTURE
PROPOSAL FOR ENVIRONMENTAL ARCHAEOLOGICAL
LABORATORY ANALYSIS AND REPORTING FOR AN
ENVIRONMENTAL ARCHAEOLOGICAL ‘WATCHING BRIEF’
AS REQUIRED (ARCHAESCAPE)
APPENDIX 6: SPECIFICATION FOR ARCHAEOLOGICAL WATCHING BRIEF ON
POTENTIAL PLEISTOCENE DEPOSITS (ARCHAEOLOGY SOUTH EAST) Brighton and Hove Wastewater Treatment Project Infrastructure WSI
SECTION 1: INTRODUCTION
1.1 RPS have been instructed by Southern Water Services (SWS) to produce this Written Scheme of Investigation (WSI) detailing the methodologies to be adopted by the archaeological contractor and paleo-environmental contractor to mitigate the impact of the construction of the pipeline infrastructure shaft sites and pumping stations associated with the Brighton and Hove Wastewater Treatment Project within Brighton & Hove and Lewes District, East Sussex. These works would be undertaken under the project management of RPS Archaeology and Historic Environment.
1.2 The transfer infrastructure will extend from Black Rock in Brighton, past Ovingdean, Rottingdean, Saltdean then on to Peacehaven and Friar’s Bay. The pipeline itself will be bored through the solid Chalk and therefore would have no impact on archaeology. However, various shaft sites and pumping stations are required along the infrastructure route and these may have some archaeological potential (Figure 1).
1.3 An Environmental Impact Assessment (EIA) has been undertaken and associated Environmental Statement (ES) been produced by RPS on behalf of SWS to identify the likely environmental effects of a proposed Wastewater Treatment Works and Sludge Recycling Centre (WTW and SRC) and its associated infrastructure (2008). The ES reported on the likely environmental effects of the development, together with the measures proposed to mitigate any adverse effects identified. The mitigation proposals within the ES (as proposed in the 2005 ES and unchanged in the 2008 ES) were accepted as appropriate by the County Archaeologist for East Sussex. The Peacehaven WTW/SRC site is the subject of a separate WSI (RPS 2008).
1.4 An outline archaeological strategy for the Project was proposed to the East Sussex County Archaeologist (in his capacity as advisor to both East Sussex and Brighton & Hove) in a meeting of 6/2/04 and outline agreement was reached on the evaluation procedure for both the East Sussex and Brighton & Hove elements of the Project. The evaluation procedures to be adopted for potential effect areas along the course of the pipeline route were agreed in a site meeting with the County Archaeologist on 25th March 2004 and consolidated in a Written Scheme of Investigation (WSI - RPS 2004). Minor variations to the requirements were subsequently agreed. The surveys
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were designed to provide site-specific information on the presence and survival of any archaeological deposits likely to be affected by the Project. The County Archaeological Officer stated that he would require archaeological watching brief (preferably strip and map) at each shaft / pumping station site as part of the Project even in the event of negative results from the evaluations (as a precaution). This requirement forms the basis of this WSI.
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SECTION 2: ARCHAEOLOGICAL AND TOPOGRAPHICAL
BACKGROUND
2.1 The scheme is located on a rolling landscape of Newhaven Chalk Downland. Solid geology comprises Upper and Middle Chalk and is overlaid in places by Clay-with- Flints and undifferentiated Head. The soils in the valley floors (e.g. at Rottingdean and Ovingdean) are deeper and retain colluvial deposits.
Archaeological Evaluation and General Archaeological Background
2.2 A complementary suite of archaeological evaluation surveys was carried out from March to August 2004 (Archaeology South East - November and August 2004 (4 reports); Stratascan, July 2004 (3 reports) - see Bibliography). The reports were included as appendices of the Culturall Heritage Chapter of the 2005 and 2008 Environmental Statement (Southern Water, 2005, 2008). These reports, in addition to the geotechnical survey data (provided as Appendix 1) informed the potential for buried archaeology at the potential impact locations.
2.3 The following programme of evaluation work was agreed with the County Archaeologist and implemented for the Project:
Evaluation of the Marine Gate Shaft site comprising geophysical (magnetometer survey) and 4% sample trial trenching (25m x 2m trench) based on the results of the geophysics (Figure 7).
Evaluation of the Roedean Way Shaft worksite comprising geophysics and excavation of a 30m x 1.6m trial trench (Figure 8).
Evaluation of an area adjacent to Saltdean East Shaft worksite comprising geophysics and excavation of a 10m x 1.6m trial trench (Figure 12).
Evaluation of the Portobello Pumping Station and associated shafts comprising geophysical survey and two 30m x 1.6m trenches (Figure 13).
Evaluation of the Peacehaven WTW/SRC site, including access road. This comprised fieldwalking survey (part of which was previously completed by the
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Brighton and Hove Archaeological Society), geophysical survey, auger bore hole survey and dry valley trench for palaeo-environmental modelling and assessment of the dry valley deposits, and targeted trial trenching, based on the results of the above.
Evaluation of the Friar's Bay Head Chamber Shaft comprising a 15m x 1.6m trial trench (geophysics not viable due to bramble cover with ecological constraints) (Figure 15).
2.4 In addition it was agreed that palaeo-environmental and archaeological assessment would be undertaken for geotechnical borehole and test pitting for the Project (Archaeoscape 2006 – see Appendix 1).
2.5 The County Archaeological Officer agreed that some of the sites were unsuitable for survey at this stage. These included Penstock (not considered necessary due to location below the wave cut platform) Marine Drive, Ovingdean, Rottingdean, Saltdean and Meridian Way. Other than the locations at which the tunnelled pipeline would rise to meet the pumping station/ shaft sites the pipeline did not require evaluation due to its depth (well below the level at which archaeological deposits might be affected).
2.6 Brighton & Hove Archaeological Society ("BHAS") were consulted at the outset of the project due to their local experience. In addition the western area of the Peacehaven WTW/SRC site had been fieldwalked by the BHAS early in 2004. Their willingness to provide the data from this exercise proved a valuable contribution to the evaluation of the archaeological potential of the site.
2.7 Black Rock Penstock Shaft: (Figures 1 & 2) The archaeological strategy in relation to the Black Rock Penstock Shaft has been agreed with the County Archaeologist. This site is below the cliff line and in an area heavily disturbed / truncated by modern development. In situ archaeological remains of Holocene date will no longer be present here. Raised Beach deposits of the Norton Raised Beach (located above within the cliff exposure) would not be directly affected by the shaft, however Mott McDonald boreholes suggests that ‘Raised Beach’ shingle deposits may be located at depths between 3.5 and 5.5m below present ground levels. These might be associated with the Pagham Raised Beach which is lower and younger than the Norton Raised Beach seen in the cliff section (Matt Pope pers. comm.). The
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associated deposits are unlikely to contain buried landsurfaces and are of lower palaeo-archaeological potential than those of the Norton Raised Beach. A watching brief has been agreed as appropriate for the limited shaft works here as a precaution. Procedures for these works are provided within Appendix 6.
2.8 Marine Gate Shaft Site: (Figures 1, 2 & 6) The archaeological evaluation strategy in relation to the Marine Gate Shaft has been agreed and carried out to the County Archaeologist's satisfaction. The c.860m2 work site is located on rough grassland adjacent to the A259. Geophysical surveys and trial trenching procedures conducted here reflect the potentially relatively undisturbed nature of the site which is located within an ASA (Archaeologically Sensitive Area). The ASA (ASA 639) is a non- statutory designation made by the County Archaeologist of East Sussex County Council for areas with high levels of previous archaeological findings. In this case the ASA extends from the Kemp Town Gas Works to just west of Roedean School and covers archaeological finds including three early Bronze Age burials, a Bronze Age cremation, Roman stray finds including coins and pottery, a Roman coffin, and a now unlocated Anglo-Saxon burial mound site (from which a sword was recovered). A Bronze Age metal hoard, a group of Bronze Age or possibly Anglo-Saxon barrows are not precisely located and might have been located within the ASA. None of the recorded find spots on the East Sussex Sites and Monuments Record were located within or close to the Marine Gate Shaft Site although map evidence suggested the location of the 19th century Black Rock Coastguard Station might lie close to the Shaft Site. The ASA also covers the Marine Drive Pumping Station site (below).
2.9 The Shaft Site lies to the east of the Raised Beach deposits whose eastern extent has been identified within the cliff line and within the Kemp Town Gasworks compound. Geophysical survey by Stratascan in July 2004 failed to identify any clear archaeological features, although modern disturbance made interpretation difficult. The subsequent trial trenching by Archaeology South East was also devoid of significant archaeology. As a result no further archaeological works are required ahead of the construction phase. An archaeological strip and map/watching brief is to be conducted as part of the Project during the initial groundworks (see methodology below and appendices).
2.10 Marine Drive (Roedean) Pumping Station: (Figures 1, 2 & 7) The archaeological strategy to date in relation to the pumping station has been agreed and carried out to
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the County Archaeologist's satisfaction. The final location at Marine Drive was discussed and archaeological strategies agreed on 14/6/04. The County Archaeologist agreed that archaeological surveys within the 3600m2 worksite area, on a traffic 'island' of the A259, will be undertaken only when the working conditions are safe to do (i.e. when road closure has taken place). Despite the location within the ASA, it is unlikely that there would be an adverse effect on archaeology due to probable modern disturbance associated with the road construction. Indeed borehole results from 2005 (Appendix 1) record 1.26m of 'made ground' above 'head' and weathered chalk at one location within the traffic island. However, in the event that archaeological remains are found by the evaluation the design of the Project allows for a window for archaeological excavation to be undertaken ahead of construction (see methodologies below).
2.11 Roedean Way Shaft: (Figures 1, 2 & 8) The archaeological evaluation strategy in relation to the shaft has been agreed and carried out to the County Archaeologist's satisfaction. The c.800m2 site is located on rough grassland adjacent to the A259. The closest sites recorded on the SMR relate to a Roman and medieval pottery scatter, perhaps indicative of settlement, to the east. The Roedean dry valley is located to the east of the Shaft Site. The geophysical survey was conducted in July 2004. Results indicated heavy modern disturbance which was confirmed by trenching to comprise 20th century disturbance to a depth of up to 1.2m over most of the 32m trench length. Given the low potential of this site for survival of significant archaeological features no further archaeological works would be required ahead of the construction. However a precautionary archaeological watching brief will be undertaken during the topsoil strip phase as part of the Project (see methodologies below).
2.12 Ovingdean Shaft: (Figures 1, 3 & 9) The archaeological evaluation strategy in relation to the shaft has been agreed and carried out to the County Archaeologist's satisfaction. The shaft site (c.2550m2 worksite) is located within the c.200m wide Ovingdean Valley. Two probable Neolithic barrows (RPS 71 & 72 - both Scheduled Monuments) are located c.450m to the east of the site but views from these to the Shaft site are concealed by St Dunstan's Hospital and by the topography. A further barrow (RPS 73) is located c.620m to the north-east and is visible from the shaft site. The effect of the shaft on the visual setting of the barrow is however insignificant. The construction of the shaft is likely to affect dry valley deposits although the small scale
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of the works in comparison to the extensive dry valley deposits does not constitute a significant effect. The recent use of the Ovingdean site as a depot means that is has been subject to construction damage via surfacing and other facilities. A geotechnical borehole has indicated 1.2m of made ground over 5.93m of gravely clay then sandy chalk rubble in a matrix of light brown clay (colluvial dry valley deposit) lying in turn above 2.77m of weathered chalk then in situ chalk. The County Archaeologist did not require evaluation due to the previous disturbance and practical considerations. An archaeological watching brief during groundworks and in particular for the removal of the present surfacing and during the extraction of dry valley deposits is however included within the Project (see methodologies below).
2.13 Rottingdean Shaft: (Figures 1, 3 & 10) The archaeological evaluation strategy in relation to the shaft has been agreed and carried out to the County Archaeologist's satisfaction. The location lies within a car park at the southern end of Rottingdean within the c.190m wide Rottingdean Dry Valley. The worksite is 390m2. As with Ovingdean the shaft is likely to affect dry valley deposits of probable prehistoric and later date. It is possible that scattered elements of the medieval village of Rottingdean could extend this far south and there is also some evidence of prehistoric burial evidence in the wider vicinity. However, the construction of the car park is likely to have at least partially truncated any archaeological remains that may have existed. Examination of a borehole at the car park by Archaeoscape (Archaeoscape 2006, Appendix A) identified modern coal and brick fragments to a depth of 2m suggesting disturbance of upper levels and noted that 'there is no evidence from the samples taken at Rottingdean of any specific or significant archaeological interest’. Examination of the geotechnical boreholes for the site in 2005 (Archaeoscape 2006) has indicated a depth of 1.2m of made ground above 'head' with in situ chalk at a depth of 7.8m. The County Archaeologist has not required prior evaluation of this small and disturbed site although watching brief/ strip and map will be conducted during the construction groundworks as a precaution. The watching brief will also entail monitoring of the extraction of dry valley deposits (see methodologies below).
2.14 Saltdean Shaft: (Figures 1, 3 & 10) The archaeological evaluation strategy in relation to the shaft has been agreed and carried out to the County Archaeologist's satisfaction. The shaft would be located on a grass verge at the corner of Saltdean Park Road and the A259 to the south east of the Saltdean Lido and would have a
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worksite of up to 980m2. The SMR records a possible Bronze Age ditch 175m to the north-east although there are few archaeological sites or finds recorded in the kilometre surrounding this location. Again the site lies within a Dry Valley. Recent archaeological evaluation within the Lido grounds did not provide evidence of archaeological remains. A nearby borehole assessed by Archaeoscape (CD 23.4) identified Made Ground to a depth of 4.01m suggesting much disturbance close to the shaft site. The verge location of the shaft site is apparently landscaped and therefore archaeological remains are unlikely to survive. Nevertheless a precautionary watching brief will be conducted during initial groundworks as part of the Project.
Brighton & Hove Project Elements Conclusions
2.15 The design of the Project has ensured that potential effects from the Brighton & Hove elements are minimised. Specifically potential effects upon archaeology from the pipeline construction are restricted to the interceptor locations since there will be no trench cutting from ground level. The infrastructure is designed such that it avoids effects on the important Palaeolithic period Raised Beach deposits, which extend eastwards across the coastal plain as far as the Kemp Town gasworks site. Construction below the wave cut platform (at the Penstock Chamber) rather than on the cliff top, in addition to avoiding more recent (Holocene) archaeology, has ensured that effects on potentially significant Pleistocene sediments, known to contain faunal remains including bones of animals known to have been hunted/scavenged by Palaeolithic hominid species, have been avoided.
2.16 Potential disturbance of evidence of the activities of the hominids themselves, such as tools and butchered animal remains, is also avoided. The potential of the shaft sites to contain significant archaeological remains is considered to be low based on the individual assessments and evaluations. However, the Project has further survey and mitigation works built in to ensure that any archaeological remains which may exist are investigated and recorded in accordance with the requirements of the archaeological advisor to Brighton & Hove. It is concluded that the Project within Brighton & Hove is unlikely to have an adverse effect on archaeology and that the Project is in accord with policy. Brighton & Hove granted planning permission on the 16th October 2005 subject to an archaeological condition.
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East Sussex Elements of the Project (Excluding Peacehaven WTW/SRC)
2.17 The Saltdean East Shaft: (Figures 1, 4 & 11) The archaeological evaluation strategy in relation to the shaft was agreed and carried out to the County Archaeologist's satisfaction. This shaft would be located on a grass verge adjacent to the A259, just west of the junction between the A259 and Hamsey Road. The worksite is approximately 800m2. The Portobello ASA lies some 50m to the east and south-east which includes an undated extant bank to the south east. The ASA also includes an extant Bronze Age barrow (SM 25477) 740m to the north-east whilst Iron Age pits have been excavated also within the ASA 490m to the north-east. Evaluation in July 2004 comprised geophysical survey which identified modern magnetic disturbance with no archaeological features apparent, followed by the excavation of a single evaluation trench. Made ground up to 0.8m depth was recorded within the trench and no archaeological features were encountered. The Project allows for an archaeological watching brief and/or strip, map and record’ procedures as a precaution during the groundworks associated with construction (see methodologies below). For the purposes of this document the following definitions apply:
Watching Brief - the Archaeological Contractor is provided with time and facilities to watch and rapidly intervene in the engineering works and recover the chance discovered resource. This will not normally result in delays to the construction programme
Strip, Map and Record - Methodology whereby the building contractor undertakes machine topsoil and subsoil removal under archaeological supervision and using a toothless bucket. The exposed geology may have archaeological features cut into it which are planned and investigated by the monitoring archaeologists ahead of any further ground reduction.
2.18 Portobello Pumping Station (and Associated Shafts): (Figures 1, 4 & 12) The archaeological evaluation strategy in relation to the pumping station has been agreed and carried out to the County Archaeologist's satisfaction. The site would include a c.2470m2 worksite area between the existing headworks and the A259. Significant archaeology is located within the Portobello ASA which extends northwards from the north side of the A259. The ASA includes a single extant Bronze Age barrow (SM 25477) 550m to the north which would not be visible from the top of the proposed
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structures. Iron Age settlement features are also known 330m to the north-west. The geophysical survey and trial trenching (two 30m x 1.6m trenches) evaluation was conducted in July 2004 and although the area was relatively undisturbed by modern activity no significant archaeological features, deposits or finds were present. The Project allows for a watching brief during topsoil stripping which would allow for excavation and recording of any archaeology not detected by the evaluation.
2.19 The Meridian Way Car Park Shaft Site: (Figures 1, 4 & 13) The archaeological strategy in relation to the shaft has been agreed to the County Archaeologist's satisfaction. The site is situated in the Meridian car park, close to the access road off Greenwich Way and would include a c.850m2 worksite. The surrounding area includes 4 ASA's associated with Mesolithic period flint scatters, and a number of Neolithic flint implements, however these were recorded within ploughsoils which have been removed at the car park site. The evaluation to the east, within the Peacehaven WTW/SRC site, area has highlighted later prehistoric farming and probably settlement cut features including two enclosures. The current land use of the site has made geophysical survey and trial trenching unfeasible and the County Archaeologist has agreed that evaluation of this heavily disturbed site was not necessary. However an archaeological watching brief will be conducted as part of the Project as a precaution (see methodologies below).
2.20 The Friar’s Bay Head Chamber Shaft Site: The archaeological strategy in relation to the shaft has been agreed and carried out to the County Archaeologist's satisfaction. The site is located at the eastern extent of the scheme the junction between Brighton Road and The Highway on rough grassland and scrub, in a relatively open location on the cliff top. The worksite area would be c.2,000m2. A Bronze Age barrow is located 500m to the west of the site within an ASA and a second ASA including an extant barrow is located 750m to the south-east at Peacehaven Heights. There is also a possible Romano-British occupation site c.130m to the north-west. The single trial trench excavated at the site in August 2004 located a single late 20th century feature but no significant archaeology was encountered. However an archaeological watching brief will be conducted as part of the Project as a precaution (see methodologies below).
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East Sussex Project Elements Conclusion
2.21 The Project has low potential to affect archaeology at the two shaft interceptor sites (Saltdean East and Meridian Way), at the Portobello Pumping Station, the WTW/SRC at Peacehaven and at the Friar's Bay Head Shaft based upon archaeological assessment and field evaluation. The pipeline links between would have no effect on buried archaeology due to deep tunnelled construction. The Project has further archaeological works built in to ensure that any unexpected archaeological remains that may exist are recorded in accordance with the requirements of the East Sussex County Archaeological Officer.
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SECTION 3: ARCHAEOLOGICAL SURVEY PROCEDURES
3.1 The following procedures have been devised following consultations with the County Archaeologist of East Sussex County Council.
Archaeological Trial Trenching at Marine Drive
3.2 The evaluation will comprise two trenches (4% sample comprising two trenches, 1X60m and 1X90m) within the currently grassed traffic island. The full procedures for the trial trenching to be undertaken by Archaeology south East under RPS management are provided as Appendix 2. Further mitigation may be required here, depending on the results of the trenching.
Strip, Map and Sample Procedures
3.3 A ‘strip, map and sample’ exercise will be conducted during the topsoil stripping at each of the works sites for the shafts and pumping stations. This basic methodology has been endorsed by the County Archaeologist with specific methods detailed below. The contractor will be required to strip topsoil/ploughsoil for the work-site areas utilising a toothless ditching bucket under constant archaeological supervision in order that archaeological features and deposits can be identified. Following the stripping of site areas the archaeological sub-contractor is required to provide a pre- excavation plan of features exposed using an EDM or GPS. This plan will form the basis of a site meeting/discussion between the County Archaeologist, the RPS archaeologist, the archaeological contractor and the client, to determine the appropriate level of recording response. The key variable will be the complexity and significance of the archaeology exposed. Low-grade landscape features (expected to be the norm) will be afforded the lower level of strip, map and sample works as set out in bullet points below, whilst should significant archaeological remains be encountered in certain areas these may be subject to preservation by record (excavation – see below and Appendix 4 for detailed methods).
3.4 To facilitate the strip, map and sample exercise a ‘window’ for a rolling programme of archaeological recording will be required. Thus archaeological works will follow the stripping programme, and will be completed and signed off prior to any further construction works in those areas. A detailed methodology for the planning and
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recording aspects of the strip, map and sample works is defined with Appendix 4. The variation from formal excavation with strip, map and record relates to lower levels of sampling. The following activities and levels of sampling are applicable to strip, map and sample:
Minimum of one experienced archaeologist to monitor two 360-degree mechanical excavators during site stripping (provided machines are working in close proximity and provided that the archaeologist complies with safe working practices as set out within the required Risk Assessment).
Features exposed will be marked up by the machine supervisors (using spray paint) for plotting (as per planning procedures in Appendix 4).
Those areas requiring full excavation will then be agreed with the County Archaeologist and would then be subject to procedures set out in Appendix 4.
For all remaining areas, i.e. those deemed suitable for the lower level of strip and map recording, up to 50% of total number of discrete features such as probable pits and post-holes (half sectioned as minimum – higher rates may be required by the County Archaeologists under some circumstances).
Large quarries or other features containing bulk homogenous fills may be suitable for machine excavation subject to agreement with the County Archaeologist.
Up to 5% excavation of slots per length of linear features.
All other recording procedures as per excavation (Appendix 4).
General Watching Brief
3.5 General watching brief is required during ground reduction for the shafts where within dry valleys (e.g. Rottingdean and Ovingdean) and for locations such as Marine Drive where topsoil stripping will only expose buried made ground and further watching brief will be required during the removal of the made ground. This will be conducted
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by Archaeology South East under RPS management and will provide a means by which archaeological artefacts and ecofacts, sealed within the colluvium, can be recovered during the site works. In addition the watching brief may provide an opportunity for further recording of soil sequences, particularly if these appear at variance with previously 2006 recorded dry valley sequences. Procedures for watching brief are included as Appendix 3 below. In the event that valley deposits of Holocene date containing stratified sequences are encountered (and are safely accessible) geo-archaeologists from Archaeoscape will attend site to assess significance and determine appropriate sampling strategies. A geo-archaeologist from Archaeology South East (Matt Pope) will be required to record and sample any deposits of Pleistocene potential (Appendix 6). This will be particularly applicable where underpinned shafts are dug to depth at Penstock and within the dry valley shafts. RPS will (on behalf of Southern Water) ensure that opportunity is provided to the County Archaeologist and the English Heritage Scientific Advisor to attend site and contribute to the formulation of any required sampling strategy.
Archaeological Excavation (if required)
3.6 Excavation of Enclosure A may be required if preservation in situ proves not to be a viable option following compaction analysis. In this case the work would be conducted by ASE, under RPS management, in accordance with the detailed excavation methodology provided within Appendix 4. In addition it has been flagged above that should significant archaeological remains be exposed during the strip, map and sample exercise that these areas would be subject to a review by the County Archaeologist, RPS and the Client. Such defined areas may then be subject to full archaeological sampling (ie at sampling ratios above those of strip and map). Where excavated, any significant archaeological remains would be subject to full assessment, analysis and publication, in line with English Heritage’s Management of Archaeological Projects (MAP 2) procedures.
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SECTION 4: BIBLIOGRAPHY
Archaeology South East, 2004. An Archaeological Evaluation at the Marine Gate Shaft Site, Brighton, East Sussex. P. Riccoboni, November 2004.
Archaeology South East, 2004. An Archaeological Evaluation at the Roedean Way Shaft Site, Brighton, East Sussex. S. Worrall, August 2004.
Archaeology South East, 2004. An Archaeological Evaluation at the Saltdean East Shaft and Portabello Pumping Station Sites, A259, Coast Road, East Sussex. S. Worrall, August 2004.
Archaeology South East, 2004. An Archaeological Evaluation at the Friar’s Bay (Head Chamber) Shaft Site, East Sussex. S. Worrall, August 2004.
Archaeoscape, 2006. An evaluation of geotechnical borehole and test pit data from locations between Brighton and Peacehaven, East Sussex. C.P. Green, 2006
Stratascan, 2004. Geophysical Survey Report. Marine Gate Shaft (Black Rock, Brighton) Brighton & Hove Waste Water Treatment Works. KT Donaldson, July 2004.
Stratascan, 2004. Geophysical Survey Report. Roedean Wat Shaft. Brighton & Hove Waste Water Treatment Works. KT Donaldson, July 2004.
Stratascan, 2004. Geophysical Survey Report. Saltdean East Shaft and Portabello Pumping Station. Brighton & Hove Waste Water Treatment Works. KT Donaldson, July 2004.
Southern Water, 2006. Brighton & Hove wastewater treatment project Appeal by Southern Water Services Limited. Appendices to the Proof of Evidence of Rob Masefield – Archaeology. May 2006
Southern Water, 2006. Brighton & Hove wastewater treatment project Appeal by Southern Water Services Limited. Proof of Evidence of Rob Masefield – Archaeology. May 2006
Southern Water, 2005. Brighton & Hove wastewater treatment project; environmental statement Chapter 6 Cultural Heritage (including figures and appendices) March 2005
Southern Water, 2008. Brighton and Hove Wastewater Treatment Project: Environmental Statement. January 2008.
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