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A staged programme of archaeological investigation, in advance of sand and gravel extraction, has been carried out at Kirkby-on-Bain since 1995. This has culminated in the excavation of an area of c.3250m2 after topsoil stripping in preparation for quarrying. Contrary to expectations, structural remains of late Neolithic date have been found along the eastern part of the site where the subsoil survives to a depth of up to 0.40m. Part of an enclosure ditch with a corner entrance is overlain by a double row of postholes extending for at least 40m along the same alignment as the filled-in ditch. A second enclosure ditch, apparently also of Neolithic date, lies to the west, again on the same alignment.
Provision was made for the cleaning, investigation and recording of up to 2500m2 of ground after topsoil stripping in preparation for sand and gravel extraction. The quarry company has exceeded this requirement but there is every reason to suspect that further features may survive in areas which have yet to be stripped of topsoil and subsoil.
Part of the site has already been stripped of topsoil and is already badly weathered. Extraction is continuing apace and there is limited time available to complete excavation of part of the site.
Lindsey Archaeological Services was commissioned by Woodhall Spa Sand and Gravel Company to carry out an assessment of the archaeological potential of their proposed quarry extension at Grange Farm (TF 238 617) in January 1995. This was required prior to determination of their planning application for sand and gravel extraction. Following evaluation of the site by trial trenching, planning permission was granted subject to the implementation of a scheme of archaeological works. The scheme required excavation of 1m2 pits set out in a grid pattern across the east field; cleaning of an area up to 2500m2 after topsoil stripping prior to sand and gravel extraction and recording of any features revealed.
The quarry is located in the Bain valley at the southern end of the Lincolnshire Wolds. The area assessed by desk-top study and geophysical survey area consisted initially of four fields west of Kirkby Lane, in Kirkby-on-Bain parish, covering c.15ha in extent. Later phases of assessment were confined to the two easternmost fields (c.7.5ha) which were scheduled to become the Phase 1 area of the extraction programme. A watching brief condition is still outstanding on the remainder of the site which constitutes the Phase 2 area for extraction.
A staged programme of archaeological investigation has been carried out in advance of quarrying comprising:
A scatter of worked flints was found by Peter Chowne during his fieldwalking survey of the Bain Valley (1983-6) but there was no other archaeological information about the site.
A magnetic susceptibility survey was carried out by Stratascan over the whole site and three areas, covering approximately 20% of the site, were selected for magnetometry.
The results were inconclusive but the survey pinpointed an enhanced zone of magnetism which coincided with the area containing the scatter of worked flints in north-east corner of the application area. The magnetometer survey failed to define any features, a result which, at the time, was interpreted as suggesting a low level of human activity.
Trial trenching was requested in order to confirm the findings of the geophysical survey. Twenty-six trenches were machine-excavated to the base of the modern ploughsoil, twenty to the west of a large drainage dyke and six to the east of the dyke. All but three measured 20m x 1.6m. They were regularly spaced across the site, but the pattern was varied to target the geophysical anomalies. Three trenches, c.5m x 6m were positioned over three circular anomalies, whilst one of the narrow trenches was placed across the most substantial linear magnetic anomaly.
The twenty trenches excavated in the larger of the two fields revealed a series of recently dug ditches/gullies and a few pits, only one of which contained any finds (a single sherd of Roman pottery). Apart from a possible modern ditch at the south end of the field there were no recorded archaeological features in the six trenches dug in the field adjacent to Kirkby Lane.
The flint scatter discovered by Peter Chowne (SMR primary record number 40125) was re-walked to define more precisely the distribution of artefacts. It extended nearly the full length of the field and, despite poor ground conditions (the field was set-aside land), some 400 artefacts were retrieved. This was followed by the hand-excavation of a 2m x 2m square trench over the densest concentration of flint found during fieldwalking. The ploughsoil was sieved to maximise artefact recovery. The subsoil was trowelled in two spits, each of 0.05m - 0.10m in thickness. One hundred and ten flints were retrieved.
The twenty-six evaluation trenches showed that there was a real absence of flint artefacts west of the modern drainage dyke and a further stage of investigation concentrated on the small eastern field adjacent to Kirkby Lane.
It was felt that, if ploughing had severely damaged the site, as demonstrated by excavations in 1981 to the east of Kirkby Lane and south-west of the present site (Chowne 1993), there was little likelihood that Neolithic features or deposits would survive. It was therefore considered that archaeological intervention after topsoil stripping would yield poor results.
After consultation with Daryl Garton a strategy of test pitting was devised in which a pit measuring 1m x 1m would be excavated per 20m x 20m grid. The grid covered the whole field, thus providing a 0.4% sample of the field. Careful plotting of artefact distribution across the full extent of the scatter would enable some spatial analysis of the material to be carried out and a provision for recording of stripped areas (up to 50m x 50m) during quarrying was also included in the scheme of works in case features should be present (Field 1996).
The test pits were positioned in the north-west corner of each 20m square using a Geodimeter total station theodolite. Each 20m square was given a grid number and the 1m square in the north-west corner was given a corresponding box number. Squares on the edge of the field which were not able to house a box in their north-west corner were still designated numbers for the plotting of fieldwalking finds. A total of sixty-four squares were fully investigated and four were partially excavated.
The topsoil was rapidly excavated by shovel in 50mm spits. All material from the topsoil was sieved and recorded in bulk (not individually plotted). Subsequent deposits were removed in 50mm spits using a trowel and each artefact encountered was individually plotted. Further finds from the spits, found during sieving, were bulk recorded. A north to south transect and an east to west transect were excavated fully to the gravels so that a profile of the stratigraphy of the site could be obtained. The few features encountered were excavated in the conventional manner.
The field had been walked over again prior to the start of excavations but lack of weathering of the ploughed soil, combined with poor light conditions, resulted in a very low retrieval rate (twenty-three flint artefacts and one sherd of pottery). It was therefore decided that during excavation of the test pits the area would be re-walked. The ground was walked at 5m intervals and finds were located to their test pit grid square (20m2). The site was fieldwalked twice using this method. Finds were also retrieved and allocated to the appropriate grid squares, but kept separate from the transect fieldwalking.
An area of 2500m2 had been allocated for the recording of archaeological remains once topsoil had been removed. The number of finds retrieved from each grid square clearly highlighted areas of considerable activity along the eastern boundary of the field. Neolithic pottery had been retrieved only from test pits at the north-east corner of the site.
Initially, three areas totalling c.250m2 were selected, all located along the eastern boundary, c.5m from the hedgeline. Only Area 1, had produced Neolithic pottery in the test pits. Area 2 was positioned mid-way down the field. Area 3, at the southern end, though having equally high numbers of flint artefacts on the surface did not have associated features appearing in test pits. These areas were expected only to produce artefacts in the subsoil. Subsoil in all three areas was to be removed by hand and the finds were allocated three-dimensional co-ordinates in the hope that clusters marking the positions of features could be identified.
Area 1 (30m x 30m, reduced to c.11m x 25m due to time restrictions)
A few features were exposed beneath the subsoil (which was deepest to the east). Thirteen flint artefacts were recovered from this area.
2.4.2 Area 2 (30 x 15.50m)
One hundred and eleven sherds of Neolithic pottery and a large number of flint artefacts were found in the subsoil. Remnants of a Neolithic ground surface survived beneath the subsoil into which were dug four possible Neolithic storage pits and four pit/posthole features which contained flints and pottery. Medieval ridge and furrow was also exposed.
A trench 41m x 4m wide was excavated extending west from Area 2 to obtain a cross section of deposits against the drain which formed the western boundary of the field. The drain appears to follow a natural watercourse which marks the limit of the flint scatter. No archaeological features were recorded but samples were taken for environmental analysis.
The zone between Areas 1 and 2 (Area 6) was sacrificed to enable sand extraction to commence. A few features were recorded during a watching brief on this area.
Area 3 (23m x 21m)
This area was disturbed by medieval ditches, as well as ridge and furrow, but a semi-circular structure comprising at least six postholes and measuring approximately 2.5m across survived, as did two gully terminals, pits and a handful of pits along a c.15m wide strip between two plough furrows.
Area 4 (20m x 20m)
The County Archaeologist requested that the ground between Areas 2 and 3 should be investigated to establish whether the density of archaeological remains was continuous. A north-south aligned Neolithic ditch together with the north-west corner of a possible later posthole structure (four postholes) cutting the ditch were found.
Area 5 (63m x 23m)
The presence of apparent structural remains in Area 4 led to a further extension and the whole strip between Areas 2 and 4 was opened up. Given the time and financial constraints it was decided that recording of finds in the subsoil would be abandoned in favour of obtaining a plan of any surviving features over as large an area as possible.
The Neolithic ditch in Area 4 continued into Area 5 and an east-west return was found. Two parallel rows of postholes were found, one of which was dug into the ditch fill. This row extended for at least 35m before its alignment ran into the eastern limits of the excavation and consisted of seven postholes. An eighth posthole at the north end may also have belonged to this alignment, extending the total length to 43m. A second row to the east, on a similar but converging alignment, comprised eight postholes and extended for at least 46m before running past the excavation limits at the south end. The north end of the alignment turned east with two more postholes/pits in the 6m gap between the corner of the post alignment and the edge of the excavations.
The limited investigation of the postholes carried out so far has yielded two sherds of Neolithic pottery and carbonised material (including hazelnuts). Part of a boundary ditch to the west, was also exposed. This had been cut through by a medieval plough furrow on a similar alignment.
The features have been recorded in plan and a sample of post-holes have been sectioned. They remain exposed and excavation of this area has not been completed.
A survey of mineral extraction and its impact upon archaeological sites in North Lincolnshire in 1976 identified the Bain Valley as one of considerable archaeological potential and led to excavation of a Bronze Age barrow at West Ashby in 1977. Further archaeological investigations were carried out at Tattershall Thorpe Neolithic settlement in 1981 (Chowne 1993).
The survival of structural remains on Neolithic sites is rare. Lincolnshire boasts only two or three examples, two of which, Newton Cliffs and Tattershall Thorpe, have been published (Chowne 1993). The features already recorded at Grange Farm Kirkby on Bain are undoubtedly truncated but survive well enough to enable the freatures to be allocated chronological phasing. Associated diagnostic pottery and flint has been found.
It is hoped that by recording as many of the surviving Neolithic features as possible and by studying the associated distribution of pottery and worked flint some understanding of the land use may be reached. The site appears to be located on the margins of land available for occupation because of intermittently wet ground conditions and it may only have been accessible on a seasonal basis. Contemporary occupation in the lower Bain Valley is known from Tattershall Thorpe and from further flint scatters (as yet not investigated). Whether these are discrete sites or indicative of transient occupation in the valley is not yet clear.
Given that the site will be totally destroyed by quarrying within the next 2-3 months the aims of the excavation will be:
The study of Neolithic and Bronze Age landscapes has been highlighted as a priority in the English Heritage Draft Research Agenda. The importance of the discoveries at Kirkby-on-Bain Quarry is enhanced by its proximity to other contemporary sites. It lies only 200m north-west of the excavations carried out by Peter Chowne in Tattershall Thorpe parish where post-holes and pits were found. The published account of these features is relatively short and could be re-examined in the light of these new discoveries to try and better understand how the landscape was being developed and exploited through the Neolithic and early Bronze Ages. A comparison of the flint assemblages may also be valuable. Of particular note at Tattershall Thorpe was the difference between the date range in the assemblages retrieved from the topsoil and the excavated features. The material found at Grange Farm appears to be more limited in date and there is considerable potential for comparing the differences in the two assemblages.
Further fieldwalking has located groups of flint (Mesolithic-Bronze Age in date) in the lower Bain Valley which point to the high potential for preserved remains beneath alluvial deposits adjacent to the River Bain. Much of this area is designated by Lincolnshire County Council for minerals extraction (Lincolnshire Minerals Local Plan 1991) and is under threat.
The accumulation of soil close to the eastern boundary hedge appears to have allowed features a greater chance of survival in a zone approximately 25m - 30m wide running parallel to this boundary. All areas excavated so far have revealed Neolithic remains. The edge of the quarry workings is 5m - 6m from the hedge, leaving a strip of c.20 - 25m wide available for investigation.
A new area between Areas 3 and 4 is proposed for excavation in order to reveal more of the structure in Area 4 and to expose the southern return for the ditch running through Areas 4 and 5.
Further excavation is proposed in three areas: Areas 5, 7 and 8. Archaeological recording will be carried out by a team of six experienced archaeologists, including a site director. The trenches will be hand-cleaned to reveal features in plan. Carefully selected cross-sections through all the features will be excavated and sampled as described below. All non-linear features containing material of high potential for environmental work will be fully excavated.
A full written (single context) and photographic record will be made of the site, to include site plans at a scale of 1:50 and section drawings at 1:10 or 1:20 as appropriate. A full photographic record will be made during the progress of the excavation to cover each feature together with general site shots. LAS operates a standard context recording system, developed by its staff over the past twenty years, based on MOLAS and CAS models.
Area 5 has been stripped of topsoil and subsoil. All exposed features have been fully planned, levelled, photographed and recorded. This area is currently exposed to weathering and is closest to the working quarry face. The quarry company intend to continue sand and gravel extraction immediately after Easter.
Requirements for further work:Area 7 area lies south of Area 4 and has not been disturbed. Neolithic features are likely to extend into this area from Area 4.
Requirements for further work:Area 8 lies to the south of Area 3 and has already been stripped of topsoil. The density of features in this area is not clear. After preliminary discussion with English Heritage and the County Archaeological Officer it has been agreed not to hand-excavate the subsoil in this area.
Requirements for further work:Environmental samples taken during the evaluation phases of the work have shown poor survival of anything but carbonised remains. Pollen and animal bone do not generally survive on the site and there is no survival of plant remains unless they are carbonised. It should be noted that the features sampled at this stage were not Neolithic in date.
Samples taken from Neolithic features during the 1997/8 season have produced hazelnuts and charcoal. Of the samples already processed three have produced enough hazelnuts to provide a C14 determination. The samples were taken from features containing associated diagnostic pottery and flint.
On the strength of the results obtained it is proposed that all excavated features should be sampled. In cases where the fill of the feature totals less then thirty litres then entire contexts of the feature will be taken as a sample. Where features contain more than thirty litres, then a thirty litre sample will be taken. Where a feature is obviously rich in remains the sample should be greater to allow for the retrieval of species less well represented.
Material will be processed during the of the excavation so that further sampling of features will be possible if necessary.. Wet sieving using a 0.5mm sieve. The flot will be dried and re-sieved to allow maximum retrieval of charcoal.
It is not anticipated that materials will require conservation, with the possible exception of fragile pottery which may need consolidation. A few pieces of Roman and Saxon pottery have been found (unstratified) which may mean that metal items of intrinsic interest could be present, although none has been found so far. All work required would be undertaken through the Lincoln Conservation Laboratory under the supervision of Robert White. Any conservation programme would be subject to recommendations arising from the Assessment Report.
Provision has already been made for post-excavation analysis and report preparation for the material excavated up to February 1998. This will be funded by the developer. Post-excavation analysis pertaining to the work funded by English Heritage will be carried out according to MAP2 specifications. The resulting Assessment Report and Updated Project Design will inevitably take account of the total assemblage of material. Any final report will need to integrate all seasons of investigation, some of which has been developer funded and some funded by English Heritage.
All finds (except metal, friable pot etc.) will be washed, marked and packed according to the Lincolnshire County Council Conditions for the Acceptance of Archaeological Project Archives. Processing of finds will be carried out by LAS before passing on to specialists for identification and assessment.
A short summary of the range quality and condition of the artefacts will be prepared. All of the artefacts from the excavation will be individually recorded and a database will be prepared to allow the sorting and plotting of the finds data by material, date, form or any other appropriate grouping at the analysis stage of the report. Environmental samples will be processed and an assessment report prepared. A copy of the paper archive will be made.
A full site matrix and a short summary comprising a descriptive account of the site will be prepared.
An Assessment Report and Updated Project Design will be prepared in accordance with Appendices 4 and 5 of MAP 2 and the draft minimum standards documentation guidelines.
It will contain:
Copies of the reports will be deposited with English Heritage, Lincolnshire County Sites and Monuments Record (SMR) and the City and County Museum, Lincoln and the National Monuments Record.
The deposition of a copy of the report at the SMR will be deemed to put all information in the public domain, unless a request is made for confidentiality. If material is to be held in confidence a timescale must be agreed with the Lincolnshire County Archaeological Officer. In normal circumstances the agreed term does not usually exceed six months.
It is proposed that the site paper archive and any archaeological finds should be deposited with the City and County Museum, Lincoln after completion of the site analysis and subject to agreement with the landowner. LAS and its sub-contractors follow the conditions laid down by the City and County Museum, Lincoln in its draft document Guidelines for the Transfer of Project Archives and will comply with their current requirements.
In addition to the Assessment Report and Updated Project, a short note summarising the main results of the project will be presented for publication to the Editor of Lincolnshire History and Archaeology with full acknowledgement to the original client and to English Heritage. The appropriate vehicle for more detailed publication will be the subject of further discussion subject to assessment of the excavation results. However, the importance of the site has already been demonstrated and it is provisionally intended to publish an account of the project results in the Proceedings of the Prehistoric Society.
Field, N. 1996 Kirkby on Bain: Sand and gravel extraction scheme of archaeological works Phase 1 Part A
English Heritage 1991 Management of archaeological projects English Heritage, London
English Heritage 1997 Draft research agenda English Heritage, London
Lincolnshire County Council 1991 Lincolnshire Minerals Local Plan
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