Slug Tests in 11 boreholes Period of data collection: July and September 2022. Slugs used were of diameters 10 cm and 5 cm. One to three repetitions of the test in each borehole. Measurements dones with an automatic pressure probe acquiring data every half second. Spreadsheet describing the groundwater observation network, including the boreholes in which the slug tests were conducted. One multiple spreadsheets file, (1.3Mo), one sheet per borehole: ASK113; FLA1; FLA2; FLA3; FLA4; ASK101; ASK102; ASK103; ASK105; HA16; RV09. Origin: MSCA Project Number: 885891 Project Acronym: IceAq Project title: Proglacial and subglacial aquifers: their evolution under climate change and the potential impacts in terms of resources and natural hazards, through the case of eastern Iceland Period of data collection: from May 2021 to September 2022, precise periods specified for each file. Area of data collection: Iceland, south-east of Vatnajökull, Suðursveit and Mýrar. Accessibility: The data can be read using e.g. the following open source softwares: LibreOffice (https://www.libreoffice.org).