Stafford Western Access Route
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SWAS/01 STAFFORD WESTERN ACCESS ROUTE GEOARCHAEOLOGICAL AND PALAEOENVIRONMENTAL REPORT commissioned by Amey November 2015 STAFFORD WESTERN ACCESS ROUTE GEOARCHAEOLOGICAL AND PALAEOENVIRONMENTAL REPORT commissioned by Amey November 2015 HA JOB NO. SWAS/01 PROJECT MANAGER Mike Kimber HAS NO. 1139 AUTHOR Emma Tetlow, Mike Kimber project info project NGR SJ 91725 23465 FIELDWORK Emma Tetlow, Robert Blackburn project team project PARISH Creswell GRAPHICS Rafael Maya-Torcelly LOCAL AUTHORITY Staffordshire County Council APPROVED BY Mike Kimber – Project Manager OASIS REF. headland3-228042 © 2015 by Headland Archaeology (UK) Ltd MIDLANDS & WEST Headland Archaeology Unit 1, Premier Business Park, Faraday Road, Hereford HR4 9NZ 01432 364 901 [email protected] www.headlandarchaeology.com PROJECT SUMMARY As part of archaeological investigations in the corridor of the Stafford Western Access Route, a two phase geoarchaeological review was undertaken. The first stage was a review of the existing borehole data produced by Sub Surface - Site Investigation, Geotechnical and Environmental Consultants. The second was a watching brief during a further stage of geotechnical works. The aim of both phases was to record the presence or absence of peat deposits across the development area (DA), and to investigate the geoarchaeological and palaeoenvironmental potential of these peats. The proposed road corridor crosses the eastern extreme of the Doxey Marshes SSSI which abuts the outskirts of the County Town of Stafford. Substantial deposits of peat, organic-rich deposits and humic silts and clays were recorded in Design Areas 1, 2 and 3. The depth varied spatially across the site, the peat found in borehole C-CP09A/R009A exceeded 10m with the base of the deposit at 13.5m. During the second phase, further investigations were undertaken within the town of Stafford and at Doxey Marsh to the west where additional deep peat sequences were located. File Name: SWAS-01-Reportv4.indd File 2015 by Headland Archaeology (UK) Ltd Archaeology Headland 2015 by © CONTENTS 1 INTRODUCTION 1 1.1 ARCHAEOLOGICAL BACKGROUND 1 2 METHOD 1 2.1 PHASE 1 1 2.2 PHASE 2 1 3 RESULTS 2 3.1 PHASE 1 BOREHOLE REVIEW 2 Design Area 1 (ILLUS 3) 2 Design Area 2 (ILLUS 4) 2 Design Area 3 (ILLUS 5 AND 6) 2 Design Area 4 (ILLUS 7) 2 Design Area 5 2 3.2 MINI-BOREHOLE REVIEW 2 Design Area 1 2 Design Area 2 2 Design Area 3 2 Design Area 5 2 3.3 WATCHING BRIEF 15 Section A – Doxey Marsh (ILLUS 9) 15 Section B – Greyfriars (ILLUS 10) 15 Section C – Sainsbury’s Supermarkets Ltd (ILLUS 11) 15 Section D – Doxey Road Railway Bridge (ILLUS 12) 15 4 DISCUSSION 15 4.1 PALAEOENVIRONMENTS 15 4.2 CULTURAL EVIDENCE 16 5 CONCLUSIONS 16 6 REFERENCES 22 7 APPENDICES 23 APPENDIX 1 BOREHOLE DATA 23 APPENDIX 2 WATCHING BRIEF BOREHOLES 27 LIST OF ILLUSTRATIONS ILLUS 1 Site location ix ILLUS 2 Site plan 3 ILLUS 3 Phase 1 - Design Area 1/Fence Diagram 5 ILLUS 4 Phase 1 - Design Area 2/Fence Diagram 7 ILLUS 5 Phase 1 - Design Area 3/Fence Diagram 8 ILLUS 6 Phase 1 - Design Area 4/Fence Diagram 9 ILLUS 7 Phase 1 - Design Area 5/Fence Diagram 11 ILLUS 8 Phase 1 - Mini Boreholes/Fence Diagram 13 ILLUS 9 Phase 2 - Section A/Fence Diagram 17 ILLUS 10 Phase 2 - Section B/Fence Diagram 19 ILLUS 11 Phase 2 - Section C/Fence Diagram 20 ILLUS 12 Phase 2 - Section D/Fence Diagram 21 File Name: SWAS-01-Reportv4.indd File 2015 by Headland Archaeology (UK) Ltd Archaeology Headland 2015 by © STAFFORD WESTERN ACCESS ROUTE (SWAS/01) 390000 390500 391000 391500 Doxey Marshes and central Staord Staord Staordshire 325000 INSETinset ILLUSillus 02 2 324500 0 200km STAFFORD 324000 illuswILLUS 202 DOXEY MIDLANDS & WEST Unit 1, Premier Business Park Faraday Road Hereford HR4 9NZ 01432 364 901 www.headlandarchaeology.com File Name: SWAS-01-Reportv4.indd File 323500 KEY development boundary CASTLETOWN natural England SSSI boundary N 0 500m scale 1:8,000 @ A3 2015 by Headland Archaeology (UK) Ltd Archaeology Headland 2015 by ILLUS 1 © Ordnance Survey © Crown copyright 2010 . All rights reserved. Licence no. AL 100013329 no. Licence reserved. rights 2010 . All copyright Survey © Crown Ordnance Site location HEADLAND ARCHAEOLOGY (UK) LTD STAFFORD WESTERN ACCESS ROUTE GEOARCHAEOLOGICAL AND PALAEOENVIRONMENTAL REPORT Anaerobic conditions, produced by these wet conditions will also 1 INTRODUCTION favour preservation of other fragile palaeoenvironmental evidence Staffordshire County Council is seeking planning permission to such as pollen, insects and waterlogged plant remains. This type of construct a new highway to the west of the county town, Stafford, evidence can be used to interrogate a number of questions including between Greyfriars Place, Doxey Road and Martin Drive. The works the nature of human activity in the area, land use, vegetation change associated with the proposed highway also require the creation of and other anthropogenic and natural factors. a flood compensatory storage site located within the Doxey and Tillington Marshes Site of Special Scientific Interest (SSSI). Drier areas of ground forming terraces, islands within, and on the fringes of the floodplain also have the potential to have been focus Headland Archaeology was commissioned to undertake a two for human activity, throughout prehistory and into the historic phase geoarchaeological review. The first stage was a review of the period. existing borehole data produced by Sub Surface – Site Investigation, Geotechnical and Environmental Consultants. The second was a watching brief during a further stage of geotechnical works. The aim of both phases was to record the presence or absence of peat 2 METHOD deposits across the development area (DA), and to investigate the The geoarchaeological review was undertaken in two phases, the first geoarchaeological and palaeoenvironmental potential of these consisted of the review of existing data from previous geotechnical peats. investigations. The second comprised an archaeological watching brief during a further phase of geotechnical investigations in September 2015. 1.1 ARCHAEOLOGICAL BACKGROUND The solid geology underlying the scheme is the Triassic Keuper 2.1 PHASE 1 Marls of the Mercia Mudstone Group, the drift geology include A geoarchaeological assessment was made of the records produced substantial deposits of alluvium (BGS 1974). This is overlain by by the developers’ geotechnical contractors, Sub Surface – Site glaciofluvial deposits (sand and Gravel) of the Devensian glaciation Investigation, Geotechnical and Environmental Consultants. All records (118,000–10,000 BP*). This area is thought to have been ice free by were made and provided by Sub-Surface geotechnical investigators 13,490 BP, nonetheless, periglacial conditions remained until the including borehole logs and fence diagrams. This initial phase of onset of enhanced climatic amelioration, a millennia later (Morgan borehole extraction and recording was not archaeologically monitored. 1973). Overlying the glaciofluvial deposits are discontinuous strips File Name: SWAS-01-Reportv4.indd File of alluvium (clay, silt, sand and gravel) associated with the River Sow. On receipt of the documentary evidence, the environmental archaeologist assessed the stratigraphy and sedimentology of each Areas of peat were identified during geotechnical investigations individual borehole. by Sub Surface (2015) and CC Ground Investigations. The peats and alluvial deposits are also associated with the Holocene activity of the River Sow. 2.2 PHASE 2 The results of each borehole have been discussed individually and describe: Such deposits may have the potential for holding both significant • Overview of the sedimentology/stratigraphy; archaeological and palaeoenvironmental evidence. Cultural 2015 by Headland Archaeology (UK) Ltd Archaeology Headland 2015 by evidence such as wooden trackways, bridges, revetments and • Presence/absence of archaeologically and palaeoenvironmentally sensitive deposits and their potential, if any. © fishing structures may be preserved as a result of waterlogging. 1 STAFFORD WESTERN ACCESS ROUTE SWAS/01 deeper and with four discrete units of organic rich material which 3 RESULTS suggest a more dynamic environment than seen in Area 1. A similar The results of the review and monitoring are described below; effect may be observed in B–CP02B/R002B which also suggests locations are shown on ILLUS 2; full stratigraphic information is given a greater degree of alluvial activity. Up to 4.8m of made ground in Appendices 1 and 2. In summary, the general distribution of overlay deposits in this area. deposits of palaeoenvironmental potential is as follows: Area Summary of deposit sequence Design Area 3 (ILLUS 5 AND 6) Phase 2/Section A Complex sequence of peat, organic rich and A single borehole was recovered from this area, as with Area 2, alluvial deposits approx 4m thick adjacent to the the stratigraphy is more complex with two units of gravelly peat River Sow; giving way to simple alluvium and intercalated by clayey peat. This finally gives way to a peat deposit then glacial deposits further from the river. with visible plant remains and shell and subsequently a silty clay with Phase 1/Design Area 1 Peat up to 10.9m thick in places present across shell. Up to 4.1m of made ground overlay these deposits. entire area overlying alluvium. Phase 1/Design Area 2 & Phase 2/Section B Thin layers of peat and organic rich deposits Design Area 4 (ILLUS 7) interleaved with alluvium with a total thickness Evidence of peat or organic rich deposits were absent in this area. of up to 13m. With the exception of one borehole, the made ground gave way Phase 1/Design Area 3 & Phase 2/Section C Layers of peat up to 3m thick interleaved with directly to unsorted glacial till. The exception was D-CP02 which organic rich alluvium with a total sequence contained several deposits of gravels, sands, clay and silt – the basal thickness of at least 15m. deposit also containing shell, which were interpreted as of alluvial Phase 1/Design Area 4 Alluvial sands and gravels.