[M-GI30] Near Surface Investigation and Modeling for Groundwater Resources Assessment and Conservation

[MGI30-04] A New Multilevel Well System Developed by Fiber Bragg Grating Technology

*Jui-Pin Tsai¹, YU-LI WANG², YEN-TE HO¹, Liang-Cheng Chang³, Tien-Hsing Dong⁴ (1.National Taiwan University, Taiwan , 2.University of Arizona, USA, 3.National Chiao-Tung University, Taiwan, 4.APOLLO TECHNOLOGY CO., LTD, Taiwan)

Keywords:Groundwater monitoring, Optical sensor, Fiber Bragg grating

This study introduces a new multilevel well developed by Fiber Bragg grating (FBG) sensors. This new monitoring system can measure depth-discrete groundwater pressure and temperature. A soft plastic tube is also installed inside the system and can conduct the hydraulic test or groundwater sampling. To examine the capability of the new well system, we have performed two field tests. In the first test, we install the FBG electric sensors (i.e. solinst levelloger) in a well, and their measurements are mutually compared. In the second test, a cross-well injection test is performed with 3 monitoring zones at each well to examine the capability of the new system. The study results show that the measurements of FBG sensors agree with those of electric sensors. We also successfully observe the depth-discrete pressure and temperature variations at each monitoring zones. These results indicate that the newly developed FBG multilevel well has the potential to be used in the field groundwater monitoring.