Borehole Integrity Survey
In May of 2022 LabAnalysis, an Italian environmental survey company, were contracted, as part of a wider project, to assess the vulnerability of a series of boreholes to surface pollution on an industrial site and to investigate the possibility for water to transfer from a settling basin into those boreholes. To achieve this, a fluorescein tracing operation was designed and implemented.
Solution
Five boreholes were identified as survey points and portable monitoring stations were deployed to each, the fluorescein dye would be injected into the industrial settling basin. The monitoring stations were to provided real time data transmission through the 4G mobile telephone network allowing the concentration of dye at each of the selected bore holes to be monitored. Alarm levels were programmed into the system to alert the survey team of the arrival of the dye in the bore holes.
To meet the survey requirements LabAnalysis and Valeport Water, with its partner Fluotechnik proposed a system that comprised the EnviroLog 4G Telemetry System interfaced with Hyperion Fluorometers designed to sense the presence of fluorescein dye. A 60 metre cable, between the topside system and the fluorometers was needed to reach the required depth. The Hyperion fluorometers, setup in an RS485 Modbus mode, can be operated with cables of many hundreds of metres.
The EnviroLog 4G topside unit was programmed to power up the Hyperions to perform an observation every 15 minutes. The observation data would be stored locally, concatenated with previously recorded data and transmitted as a single data file every 6 hours to the data hosting service, valeport.cloud. Should a programmed alarm level for the dye be reached at any of the sites, then an immediate broadcast of data and SMS messages could be sent.
Feedback from survey team
- Real-time dye trace monitoring was achieved
- During the measurement campaign, by selecting a sophisticated telemetry system such as EnviroLog 4G, we were able to reprogram the system remotely. In this way, the measurement strategy could be adjusted to suit the situation, without the need to visit the site.