Viking CCS Pipeline Lincolnshire: Archaeological Metal Detecting Survey

All works were undertaken in accordance with the detailed methods set out within the WSI. Any significant variations to these methods were agreed with the Viking CCS Heritage Consultees and the Client prior to being implemented. The methods employed are summarised below. General The non-intensive survey was conducted using a series of regularly spaced transects laid out on two perpendicular axes orientated along the longest boundary within each field. The survey was conducted across the entire 26.3-hectare area using a ten metre transect spacing. The results of this non-intensive survey were presented to the consultant and was used to define any areas of intensive survey that may be required to clarify the extent, character, and complexity of the artefact distribution. Due to the general lack of finds (see results and finds sections below) it was decided no intensive survey was required (which would have been 2 metre spaced transects laid out on two perpendicular axes orientated on the same grid as the non-intrusive surveys). Prior to surveys commencing soil chemistry was analysed to inform the potential for metal artefact preservation. This was conducted using a Hanna Instruments HI-83141-1 portable pH/mV meter and was performed systematically across all fields included in the survey area. All transects were set out using a Global Navigation Satellite System (GNSS) with a marker at 30 metre intervals. Markers will consist of wooden canes with hazard tape flags which may be left out overnight on consecutive survey days but not over weekends or if there are any gaps in the survey programme. Surveys were completed by a team of five archaeologists, of which four will be prospecting along consecutive transects with metal detectors, while the fifth assess any recovered finds against the discard policy and subsequently bags, numbers, and spatially locates any finds retained for analysis. All retained finds were given a unique number with their spatial location recorded using a GNSS against Ordnance Survey (OS) National Grid and Ordnance Datum (OD) (Newlyn), as defined by OSTN15 and OSGM15 transformation. No artefacts will be recovered beyond the depth of the plough soil and will be excavated using appropriate tools with all efforts made to minimise ground disturbance. Metal detecting was undertaken using Garrett EuroAce detectors and pin pointers. Set out and spatial recording was undertaken using a Leica Captivate NetRover Global Navigation Satellite System or an equivalent instrument. It will be set to a minimum three-dimensional accuracy of 30 mm. Recording A Leica GNSS connected to Leica's SmartNet service surveyed the location of archaeological finds. All survey data is recorded in OS National Grid coordinates and heights above OD (Newlyn), as defined by OSTN15and OSGM15, with a three-dimensional accuracy of at least 50 mm. Finds strategy Strategies for the recovery, processing and assessment of finds were in line with those detailed in the WSI. The earliest find is a Roman nummus issued by the House of Valentinian, dating from AD 364-78. Previous geophysical survey of field 70, from which the coin was found, had suggested the presence of a potential trackway and series of enclosures or land divisions. A number of ditches and gullies have been confirmed during the in-progress evaluation, which are currently thought to be Romano-British. The coin evidence hints that the settlement activity might be able to be refined to a late Romano-British date. A second coin of unclear denomination is likely to be post-medieval or modern based on its size. The rest of the material is also post-medieval or modern, or remains undated, and is largely related to agricultural activity. No artefacts were recovered that relate to the nearby Anglo-Saxon cemetery at Welbeck Hill, or the Civil War earthwork adjacent to the pipeline route.