Supplementary Material to Accompany the Manuscript; Dissolved Oxygen and Dissolved Inorganic

Supplementary material to accompany the manuscript; Dissolved oxygen and dissolved inorganic carbon stable isotope composition and concentration fluxes across several shallow floodplain aquifers and a diffusion experiment. Authors, Stephen R. Parker, Marissa N. Darvis, Simon R. Poulson, Christopher H. Gammons, Jack A. Stanford.

Figure Suppl. 1: Map of the Nyack field area showing wells sampled. The Middle Fork of the Flathead River (MFFR) flows from southeast to northwest along the eastern boundary of the floodplain. Beaver Creek, a springbrook channel, is shown in the orthofluvial portion of the site. Water table elevations are from Aug. 2009. Well site MFL2 is near the head of the floodplain and is the in the “Movie” area which is one of the main recharge zones for the aquifer. (Figure adapted from Smith et al. 2011)

Figure Suppl. 2: Map of Silver Bow Creek (SBC) field site showing wells sampled and the surface site reported (SBC-16a). SBC flows from east to west through the central portion of the site. The sampling sites SBC2 and 3 are shown for reference and were used by Gammons et al. 2011.

Figure Suppl. 3: Map of the Umatilla River floodplain field site. The Umatilla River flows east to west along the northern boundary of the floodplain. The wells sampled are shown (UMW, Å).

Figure Suppl. 4: Schematic of the diffusion tank experiment used to simulate diffusion of O2 from the atmosphere to the mixed water below through a simulated capillary fringe made with foam beads.

Table Suppl. 4: Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) analyses for selected analytes from the Umatilla, Nyack and SBC sites.

All concentrations are mg/L. PQL=practical quantifiable limit; b.d.=below detection; RL=reporting limit. Umatilla and Nyack analyses performed at Univ. of Montana, Biogeochemistry Lab following EPA method 200.7. SBC analyses were performed at the MSE Laboratory in Butte, MT following EPA method 200.7.

Table Suppl. 5: Ion Chromatography (IC) analyses for the Umatilla, Nyack and SBC sites.

All concentrations are mg/L. PQL=practical quantifiable limit; b.d.=below detection; NA=Not available. Umatilla and Nyack analyses performed at Univ. of Montana, Biogeochemistry Lab following EPA method 300.0. SBC analyses were performed at Montana Tech in Butte, MT following EPA method 300.0.

Table Suppl. 6: Summary of physical and chemical parameters for wells sampled in June 2008 at the MPTP site (adapted from Parker et al. 2012).

Table Suppl. 7: A summary of field parameters and analyte concentrations for river and well waters sampled at the Nyack site in Aug. 2008 (adapted from Smith et al. 2011).