BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:EESS talk on "The End of the Pipe:  Using Aquatic Chemistry to Con
 trol Lead Concentrations in Tap Water"
DTSTART:20201124T121500
DTEND:20201124T130000
DTSTAMP:20260506T180720Z
UID:23584da5363002902ef3f3915c610a253ae378b7c10e3d6a2cbd28e5
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr Daniel Giammar\, professor\, Aquatic Chemistry Laboratory\,
  McKelvey School of Engineering\, Washington University in St.Louis\, USA\
 nAbstract:\nThe legacy of lead-containing materials used for water supply 
 poses challenges to tap water quality.  In contrast to drinking water con
 taminants that have their origins in the source water and can be removed a
 t a treatment plant\, the source of lead in drinking water is the pipe tha
 t connects a home to the water main and the plumbing within the home.  Co
 ncentrations of lead in tap water are governed by the chemical reactions b
 etween the water in the pipe and the scale of solid phases that develops o
 n the inner surface of the pipe.  Perturbations of the water chemistry ha
 ve resulted in high profile crises of lead in drinking water (e.g.\, Washi
 ngton\, DC and Flint\, Michigan).  However\, adjustment of the water chem
 istry is also a lever that can be used to minimize lead release to drinkin
 g water.\n\nBench-scale and pilot-scale experiments have explored the infl
 uence of water chemistry on lead in drinking water.  The effectiveness of
  orthophosphate as a corrosion inhibitor and its impact on the composition
  and structure of pipe scales was evaluated in a series of bench-scale exp
 eriments with lead pipes.  The responses of the lead pipes were examined 
 for scenarios involving (1) orthophosphate addition in advance of a change
  in disinfectant from free chlorine to chloramine and (2) application of o
 rthophosphate at a pH value higher than the range over which it is typical
 ly used.  The formation and stability of lead(IV) oxide (PbO2)\, a low so
 lubility solid that is only stable in the presence of free chlorine\, is a
 n example of the importance of oxidation-reduction reactions.  Redox reac
 tions are also relevant to the galvanic corrosion that can occur during pa
 rtial lead service line replacements.  More recent work is exploring the 
 influence of the blending of reclaimed wastewater and conventional sources
  on lead release.\n\nShort biography:\nProfessor Giammar is the Walter E. 
 Browne Professor of Environmental Engineering in the Department of Energy\
 , Environmental and Chemical Engineering at Washington University in St. L
 ouis.  Professor Giammar's research focuses on chemical reactions that af
 fect the fate and transport of heavy metals\, radionuclides\, and other in
 organic constituents in natural and engineered aquatic systems.  His rece
 nt work has investigated the removal of arsenic and chromium from drinking
  water\, control of the corrosion of lead pipes\, geologic carbon sequestr
 ation\, and biogeochemical processes for remediation of uranium-contaminat
 ed sites.  Professor Giammar is currently an Associate Editor of Environm
 ental Science & Technology.  Professor Giammar completed his B.S. at Carn
 egie Mellon University\, M.S. and Ph.D. at Caltech\, and postdoctoral trai
 ning at Princeton University before joining Washington University in St. L
 ouis in 2002.\n 
LOCATION:ZOOM
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR