Our specialist services Desk-Based Assessment The initial stage of formulating a site investigation strategy often involves an examination of the existing geological resources pertaining to an area, such as maps, archives and existing borehole records. Learn more Borehole Surveys ARCA offers a range of borehole drilling services for the investigation of sedimentary sequences buried too deeply for conventional excavation. Learn more Deposit Modelling ARCA has extensive experience of using geotechnical and other borehole data to generate deposit models, as well as composite stratigraphic cross sections. Learn more Pleistocene and Palaeolithic geoarchaeology ARCA is one of very few commercial organisations specialising in the Old Stone Age or Palaeolithic period. We investigate deeply buried stratigraphy dating back hundreds of thousands of years and potentially containing evidence of early or pre-modern human activity. Learn more