Posiva publishes Working Reports and Posiva Reports. From the year 2006 nearly all the reports have been published on our webpage and they can be found in the databank. In the databank you can also find our Annual Reviews and some other publications as well. You can also find print-quality pictures and useful links in the databank.

Recent publications

Workreport 2018-28



Hydraulic Conductivity Measurements with HTU at Eurajoki, Olkiluoto, in Drillhole OL-KR56 in 2017


Pulkkinen, P., Hurmerinta, E.



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As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with the HTU-equipment in drillhole OL‑KR56 on the Olkiluoto investigation site. The objective was to in­vestigate the distribution of the hyd­rau­lic conductiv­ity in the sur­rounding bedrock volume. In OL-KR56 measurements were carried out between July and August 2017.

The total length of the drillhole OL-KR56 is 1201.65 m, of which 404.00 m was covered by 203 standard tests with 2 m packer separation as specified in the measurement plan. These numbers include two equipment tests measurement near the surface in OL-KR56. Double-packer cons­tant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted nor­mally 20 min­u­tes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended if longer times were needed to obtain correct results or when suited to the working schedule. Two tran­sient (Horner and 1/Q) in­terpreta­tions and one stationary-state (Moye) in­terpreta­tion were made in-situ immediately after the test.

The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Pöyry Finland Oy.


HTU, hydraulic conductivity, constant head test, hydraulic injection test


WR 2018-28_web (pdf) (7.1 MB)


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