ambiguity that we see in some of our data sets that make the use of, for example, electrical geophysics less appealing to non-geophysicists (is that conductive feature a sandy unit in highly saline groundwater, or is it a clay unit?). We are also starting to improve the quality of our products by better incorporating ancillary data. I have rabbited on before about the use of NMR in groundwater work to help with this discrimination process, and foresee this as becoming more common - even though NMR is still an expensive technique to run. I am hoping to see more joint inversion of various data sets to produce maps of, what to me is one of the holy grails of the geo-hydrological world – hydraulic permeability (as well as other parameters that are of interest to engineers, etc.). An area of research that was not really on the radar 25 years ago is the study of uncertainty, and its propagation through to the various products that we generate. This is looking like a“growth industry”in the environmental field in general. I also think that there are now research/work opportunities that could not possibly have been foreseen in the mid-nineties: the growth of non- conventional energy sources and the often contentious fracking process. We need to do more to improve our ability to image hazards that have the potential to affect the integrity of the fracked well, thereby making the process safer and even, possibly, help to improve the public’s perception of the unconventional gas producing process. And finally Bob, in his article, reminded me of two technological aspects that I think are interesting and could usefully be revisited in environmental geophysics. The first is the careful correlation of soil types with response from, for example, “simple”terrain conductivity metres like the Geonics EM-38. I don’t do enough of this myself, but I suspect that correlations could be improved with the use of well- inverted data sets. The second is the Radiowave Electromagnetic Methods that were of interest in the mid to late 1990s. Coincidentally, I was recently reminded of this research in discussions with another group, and am motivated to look further into these methods and to see why we don’t hear much about them these days. Stay tuned! References Romig, P. R. 1994. Environmental geophysics – fad or future. 1994 SEG Annual Meeting. Los Angeles, CA: Society of Exploration Geophysicists. Whiteley, R. 1994. Environmental geophysics: Challenges and perspectives. Exploration Geophysics 25, no. 4: 189–196. 25 PREVIEW Environmental geophysics FEBRUARY 2019