Carloggas Farm St Stephen, St Austell Cornwall Archaeological Excavation and Watching Brief
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Carloggas Farm St Stephen, St Austell Cornwall Archaeological Excavation and Watching Brief for Good Energy CA Project: 4696 CA Report: 15093 June 2015 Carloggas Farm St Stephen, St Austell Cornwall Archaeological Excavation and Watching Brief CA Project: 4696 CA Report: 15093 Luke Brannlund, Project Supervisor prepared by Peter Busby, Project Supervisor date 9 June 2015 checked by Ian Barnes, Project Manager date 9 June 2015 approved by Laurie Coleman, Principal Fieldwork Manager signed date 28 June 2015 issue 01 This report is confidential to the client. Cotswold Archaeology accepts no responsibility or liability to any third party to whom this report, or any part of it, is made known. Any such party relies upon this report entirely at their own risk. No part of this report may be reproduced by any means without permission. © Cotswold Archaeology Cirencester Milton Keynes Andover Building 11 41 Burners Lane South Stanley House Kemble Enterprise Park Kiln Farm Walworth Road Kemble, Cirencester Milton Keynes Andover, Hampshire Gloucestershire, GL7 6BQ MK11 3HA SP10 5LH t. 01285 771022 t. 01908 564660 t. 01264 347630 f. 01285 771033 e. [email protected] © Cotswold Archaeology Carloggas Solar Farm, St Stephen, St Austell, Cornwall: Archaeological Excavation and Watching Brief CONTENTS SUMMARY ..................................................................................................................... 3 1. INTRODUCTION ................................................................................................ 4 The site .............................................................................................................. 4 Archaeological background ................................................................................ 5 Archaeological objectives ................................................................................... 5 Methodology....................................................................................................... 5 2. RESULTS (FIGS. 2-14) ...................................................................................... 7 3. DISCUSSION ..................................................................................................... 12 4. CA PROJECT TEAM .......................................................................................... 14 5. REFERENCES ................................................................................................... 14 APPENDIX A: CONTEXT DESCRIPTIONS .................................................................... 16 APPENDIX B: THE FINDS .............................................................................................. 30 APPENDIX B: THE WORKED STONE ........................................................................... 31 APPENDIX D: OASIS REPORT FORM .......................................................................... 33 LIST OF ILLUSTRATIONS Fig. 1 Site location plan (1: 25,000) Fig. 2 Overall field location plan (1: 3000) Fig. 3a Detailed plan showing trench locations and geophysical survey results, Fields A-C (1:1000) Fig. 3b Detailed plan showing trench locations and geophysical survey results, Fields D-G (1:1000) Fig. 3c Detailed plan showing trench locations and geophysical survey results, Fields H-J (1:1000) Fig. 3d Detailed plan showing trench locations and geophysical survey results, Fields K-M (1:1000) Fig. 4 Section (1:20) and photograph, Cornish Hedge between fields J & M Fig. 5 Sections (1:20) and photographs; Trenches 20 and 543 Fig. 6 Excavated area Trench 30, with rectified vertical photography (1: 100) Fig. 7 Sections (1:20) and photographs, excavation area Trench 30 (fogou) Fig. 8 Photograph, view of fogou facing north-west (scale 1m) 1 © Cotswold Archaeology Carloggas Solar Farm, St Stephen, St Austell, Cornwall: Archaeological Excavation and Watching Brief Fig. 9 Excavation area, Trenches 1A & 1B, with geophysical survey data (1:200) Fig. 10 Sections (1:20) and photographs, Trench1A Fig. 11 Sections (1:20) and photographs, Trench1A Fig. 12 Extract from the Tithe Map of 1839 Fig. 13 Extract from the Ordnance Survey map of 1881 Fig. 14 Subterranean void in field H (end of 2m scale) 2 © Cotswold Archaeology Carloggas Solar Farm, St Stephen, St Austell, Cornwall: Archaeological Excavation and Watching Brief SUMMARY Project Name: Carloggas Solar Farm Location: St Stephen, St Austell, Cornwall NGR: SW 9552 5412 Type: Watching Brief Date: 20 January 2014 to 14 January 2015 Planning Reference: PA13/06288 Location of Archive: To be deposited with Royal Cornwall Museum Site Code: CFC 14 An archaeological watching brief was undertaken by Cotswold Archaeology during groundworks associated with the development of the Carloggas Solar Farm, St Stephen, St Austell, Cornwall. In the eastern part of the site, a fogou was identified surrounded by a number of undated features. In the south-eastern part of the site, a number of possible Iron-Age/Romano features were identified, though the limited quantity of secure dating evidence precludes a detailed interpretation of the majority of the features. A series of former field systems were also noted across site, and two possible mining related voids were identified. 3 © Cotswold Archaeology Carloggas Solar Farm, St Stephen, St Austell, Cornwall: Archaeological Excavation and Watching Brief 1. INTRODUCTION 1.1 Between January 2014 and January 2015 Cotswold Archaeology (CA) carried out an archaeological excavation and a watching brief for Good Energy at Carloggas Farm, St Stephen, St Austell, Cornwall (centred on NGR: SW 9552 5412; Fig. 1). The watching brief was undertaken to fulfil Condition 10 attached to the planning consent for a solar farm and associated infrastructure (Cornwall Council (CC) planning ref: PA13/06288). 1.2 The excavation and watching brief were carried out in accordance with a brief (Cornwall Council 2013) prepared by Dan Ratcliffe (Historic Environment Planning Advice Officer), and with a subsequent detailed Written Scheme of Investigation (WSI) produced by CA (2014) and approved by Dan Ratcliffe and Phil Copleston (Senior Development Officer (Historic Environment). The fieldwork also followed the Standard and guidance for an archaeological watching brief (IfA 2009) the Management of Archaeological Projects 2 (English Heritage 1991) and the Management of Research Projects in the Historic Environment (MORPHE): Project Manager’s Guide (EH 2006). The excavation was monitored by Dan Ratcliffe 28 January 2014 and the watching brief was monitored by Phil Copleston on the 23 October 2014. The site 1.3 The proposed development is approximately 20.4ha in extent, and comprises two areas of agricultural fields of roughly equivalent size, located to the east and west of a minor road running between Gwindra and Goonabarn (see Fig. 1 for location and extent). The site is surrounded by undulating farmland, which rises from approximately 190m AOD in the southwest to 220m AOD in the northeast. 1.4 The underlying bedrock geology of the majority of the development area is mapped as St Austell Intrusion – Microgranite of the Permian and Carboniferous Periods. The south-eastern extent of the site crosses into Meadfoot group – Hornfelsed slate and sandstone. No superficial deposits were recorded (BGS 2015). In the north of the site, clay sand with angular granite boulders and stones were encountered at the base of excavations (Fields A, B, C, D, G, H and I: Fig. 2). In the southeast of the site silt clay with slate gravel was encountered (Fields E, F, I, J, K, L and M: Fig. 2). 4 © Cotswold Archaeology Carloggas Solar Farm, St Stephen, St Austell, Cornwall: Archaeological Excavation and Watching Brief Archaeological background 1.5 An archaeological desk-based assessment (CA 2013) and geophysical survey (Stratascan 2013) were completed in support of the planning application. The following is a summary of these documents. 1.6 Two Scheduled Monuments (SMs) are recorded near to the site. These comprise St Stephen’s Beacon Hillfort (SM ref 1003091), located c.300m north-east, and a prehistoric round (SM ref 1007291), located c.150m north-east of the site (Fig. 2) (CA 2013). 1.7 The site lies within an area of Anciently Enclosed Land (AEL), reflected in the extant agricultural character of the landscape. AEL can variously have prehistoric or medieval origins, and the farming settlements in these areas are typically documented from the 17th century or earlier (CC 2013). This site specifically is located in the vicinity of post medieval industrial remains: mineral extraction is known to the northwest (CA 2013). 1.8 The geophysical survey identified a number of probable archaeological anomalies which were interpreted as field boundaries, correlating to those illustrated on the 1839 Tithe Map. A series of anomalies in the southeast of the site were highlighted as being potentially indicative of enclosure ditches (Stratascan 2013). Archaeological objectives 1.9 The objectives of the archaeological works were: to monitor groundworks, and to identify, investigate and record all significant buried archaeological deposits revealed on the site during the course of the development groundworks; at the conclusion of the project, to produce an integrated archive for the project work and a report setting out the results of the project and the archaeological conclusions that can be drawn from the recorded data. Methodology 1.10 The fieldwork followed the methodology set out within the WSI (CA 2014). 5 © Cotswold Archaeology Carloggas Solar