ESTCP Project #1011, Rhizosphere
Table 1. Performance objectives.
Actual Performance Objective Met?
Visual inspection of plots
established on plots
following seeding and
Relate success of
Use statistically valid time-
Yes. Using biomarker and growing
series samples to develop
degree-day normalized data, statistical
equations to describe
significance was shown for planted plots
relative to un-planted plots.
Measure degrader numbers
Yes at Annette Island site. Significant
via MPN methods
effects at one of three sites. Microbial
data support chemical data results.
Use selective media
Yes at Annette Island site, significant
techniques to compare
changes in fungal and microbial
fungal and bacterial
populations were related to plant and
fertilizer treatments, respectively. At
Barrow, plants increased the amount of
fungal biomarkers relative to non-planted
Rate of degradation
Contaminant depletion rates, biomarker
and growing-degree day normalized
show greater depletion of specific
petroleum fractions relative to unplanted
Partial. Data show significantly greater
not expected to become
rates for planted treatments relative to un-
planted treatments. Rhizosphere-enhance
treatment is a long-term treatment
strategy useful to remote sites, large
areas, and locations/situations where
other alternatives do not exist.
3.2 Selecting Test Sites
To include a climatic gradation evaluation of rhizosphere-enhanced bioremediation, we chose
three sites on a south to north gradient of climatic conditions. Sites were selected to maximize
the potential for successful demonstrations and to meet DoD requirements associated with
ESTCP. We based our selection on the following criteria:
1. For maximizing future application and to gain the most information from the
demonstrations, we sought three sites, each in a different climatic zone in Alaska.