08-14-2018, 02:09 AM
That was a good interview - maybe the best summary introduction to geothermal / PGV so far. Listening to Sherri ask her "innocent" but conveniently pointed questions is quite entertaining. Look forward to part 2 next week - thanks for sharing!
I do have to question one thing Dr Thomas said though - "when we look at the chemistry of the fluids we don't find high levels of toxic elements like arsenic or boron or ammonia in Hawaii's geothermal fluids because the rocks are not rich in those elements. ... Geyer's geothermal fields ... there is mercury, lead that has contaminated the streams..."
However, in the analysis of PGV brine arsenic (Ar) has been over 2000 ppm, and mercury (Hg) has been around 2 ppm, which is way higher than the Geyer's Geothermal field values of 0.2 ppm for arsenic and 0.005 ppm for mercury. PGV's brine does have Lead (Pb) as well, up over 4%, but I don't have numbers for boron or ammonia to compare which may be what he was trying to highlight? I'm sure someone can clarify this point hopefully.
PGV Brine Analysis (Table 1): http://pubs.geothermal-library.org/lib/grc/1028353.pdf
Geothermal Energy (Table 8.1 Contaminant concentrations) http://unesdoc.unesco.org/images/0013/00...33254e.pdf
I do have to question one thing Dr Thomas said though - "when we look at the chemistry of the fluids we don't find high levels of toxic elements like arsenic or boron or ammonia in Hawaii's geothermal fluids because the rocks are not rich in those elements. ... Geyer's geothermal fields ... there is mercury, lead that has contaminated the streams..."
However, in the analysis of PGV brine arsenic (Ar) has been over 2000 ppm, and mercury (Hg) has been around 2 ppm, which is way higher than the Geyer's Geothermal field values of 0.2 ppm for arsenic and 0.005 ppm for mercury. PGV's brine does have Lead (Pb) as well, up over 4%, but I don't have numbers for boron or ammonia to compare which may be what he was trying to highlight? I'm sure someone can clarify this point hopefully.
PGV Brine Analysis (Table 1): http://pubs.geothermal-library.org/lib/grc/1028353.pdf
Geothermal Energy (Table 8.1 Contaminant concentrations) http://unesdoc.unesco.org/images/0013/00...33254e.pdf