5 the average concentration of paired samples from 10 m into the wetland (14.8 ± 4.5 mg kg−1). These values were not statistically different (p = 0.31; t = 1.02; df = 90). The average concentrations for PAHs were 2.7 times higher than samples from 1 m into the wetland, compared with 10 m inland (3427 ± 2,072 vs. 1168 ± 305 μg kg−1), and were not statistically significantly different from each other (p = 0.28; t = 1.08; df = 90). The variability from 1 to 10 m is such that there might be a 10-fold difference, either higher or lower, in the concentration

of PAHs and a lesser amount for target alkanes ( Fig. 3). These results are similar to those of Culbertson Doxorubicin nmr et al. (2007a) who demonstrated high spatial heterogeneity over as little as 5 m in the concentrations of oil remaining in salt marshes 20 years after the West compound screening assay Falmouth, MA, oil spill. The concentrations of target alkanes and PAHs measured in June 2011 and September 2011 along a 90 or 100 m transect (Fig. 4) illustrate how this small reduction from 1 to 10 m continues further into the wetland with only a slight attenuation in concentration, if any. It is not surprising that oil would be carried 100 m into the wetland

in light of the multiple high water events between 2010 and the end of 2012 (Fig. 5). The tidal range is nominally around 30–50 cm throughout these estuaries, whereas the three tropical storms and two hurricanes inundated the wetland between 50 and 100 cm water depth. The turbulence of the storms and water height also came with currents that would have mobilized oil in the wetlands, Dichloromethane dehalogenase bays, or even offshore, and brought it into and over the wetland and perhaps out again. There was not a good correlation between the five SCAT categories of shoreline oiling observed

during the active portions of the spill and the quantity of oil at the same sites that were measured in our study (Fig. 6). There was no difference in the average concentration of aromatics at all SCAT sites that were oiled or not. Further, there was no difference in the amount of oil amongst the SCAT categories for the specific site where the sample came from. These results agree with the conclusion of Michel et al. (2013; p. 4) that “these descriptors are not adequate by themselves to develop cleanup strategies and goals for each habitat type or shoreline segment.” The SCAT team assessments are a necessary first-order assessment for many purposes, including near real-time response operations, but these assessments may not be useful for quantifying relationships between dose and response, changes with time, or spatial distribution horizontally and vertically. Field observations comparing oil exposures along the marsh shoreline should consider taking their own site-specific measurements of oil concentration rather than rely on these surveys to define the relative exposure at the plot level (e.g., 1–10 m). The average concentration of target alkanes and PAHs for each sampling trip are in Fig.