Your browser is no longer supported. Please upgrade your browser to improve your experience.

Dye tracing at depth

Posted February 22, 2023  |  Application Notes

As part of a project in the Dordogne, CPGF Horizon were contracted to investigate the susceptibility of a well to surface pollution. The project was further complicated by:
• The requirement to install equipment at a depth of more than 100 metres
• A complex installation - the cable had to pass through cable glands and packers to maintain the integrity of the well.


In order to meet the objectives of the project, Valeport Water together with its partners, Fluotechnik and PMH, supplied the required dye – Fluorescein and rented an EnviroLog 4G Telemetry system interfaced to two Fluorescein Hyperion fluorometers along with cabling of the required length.

The EnviroLog 4G system was programmed to wake up the Fluorometers and take a measurement every 5 minutes and telemeter the logged data, every 2 hours, to the web data hosting service Valeport.Cloud.  Here the data was displayed in both graphical and alpha numeric form and also available to download – see

Due to the complexity of the installation, Valeport Water provided technical support to CPGF Horizon during the installation phase.

Customer Feedback

  • Near real-time tracking of the dye tracing campaign was achieved without the survey team having to be on site for the full duration of the survey.
  • The EnviroLog 4G system is capable of two way communication. During the survey the system was remotely interrogated and the measurement scenario was successfully adjusted as required.  In this way the measurement strategy could be adjusted without the need for an engineer visit the site.  This functionality was recognised by the CPGF Horizon survey team, based in Poitiers, as major advance in their survey capability, by saving time and cost, for no loss in data quality coupled with greater control of the survey process.