Seaton Carew Saltern, North Gare, Hartlepool: post-excavation assessment

A topographic and geophysical survey was conducted prior to excavation, the later providing a focus for the location of five 6m by 1m trenches. Due to time restraints only three trenches (1, 4 and 5) were excavated and recorded. The topographic survey recorded a probable saltern mound, an earth bank at the western edge of the survey area, and a dry river inlet to the east thought to relate to a medieval saltern. An earth bank on the eastern edge of the survey area is probably related to the modern car park. Anomalies in the geophysical survey reflecting probable burnt ash and other industrial waste deposits including slag, clinker, and possible brick rubble, have been detected broadly coextensive with the mound. Possible structural elements have been identified, including possible kerbs, and salt pans. An earth bank, of uncertain age and purpose, has been detected in the west of the survey area. Natural variation typical of wetland environments has been detected across the survey area. Occasional small areas of disturbed ground have been identified beyond the mound. Three trenches were excavated. Laminated deposits and layers of soil were recorded in trenches 1 and 2 forming the upper part of a mound; the base of the mound was not reached. These were interpreted as being waste deposits from the 'sleeching' process during salt production. Industrial residue was present in several of the deposits, including a large quantity of fuel ash slag, too large for domestic debris, which could also be related to salt production. Briquetage was however absent, which is unusual for this type of site. Bromine was also recorded within some of the industrial residues, potentially indicating they had been in contact with salt water. The samples comprise deposits of coal and cinder with some having large amounts of burnt concreted material possibly consistent with saltern waste residues. There are also assemblages of marine and brackish-water molluscs alongside a few fish bones. Charred plant macrofossils are absent and there are only traces of charcoal. Based on the palaeoenvironmental evidence there is nothing diagnostic in terms of dating the features, although the predominance of coal waste is consistent with a medieval or later date and may reflect the importance of this fuel for the industrial activity undertaken at this site.