Marcus Christian, a systems analyst with AECOM, took these pictures at an abandoned mine site near Clearlake CA.
"Sampling is for ppt mercury analysis so has to be very precise. Additionally, the streams are ephemeral so can only be sampled after sufficient rain. Something of an issue with the west coast drought."
"Had perfect weather on our last sampling event so figured it was time to get a few extra photos for this competition. Equipment was rented as always from Mike in the Sacramento office."
Rachel Avila is doing the sampling with a Geotech Geopump peristaltic pump.