The Compatibility of Slurry Cutoff Wall Materials with Contaminated Groundwater

Temporal studies were conducted from mid- to late-harvest season of `Ruby Red' grapefruit (Citrus paradisi Macf.) to evaluate the effect of on- and off-tree storage, fruit size, and juice vesicle position on the development of granulation. Juice vesicle fresh and dry masses were highest at the stem and stylar positions of the fruit section and were not affected significantly by time of harvest or by storage. Juice vesicles isolated from each position were subjectively evaluated for the presence of granulation. Granulation was highest in stylar juice vesicles obtained from large fruit (≈600 g) that were harvested late in the season (March and May) and stored in air at 21 °C for 60 days. Large fruit harvested in March and May and examined immediately, and fruit harvested in January and stored for 60 days had low granulation scores. Thus, fruit remaining on the tree until May are less susceptible to the disorder than those harvested in March and held in storage until May. Levels of alcohol-insoluble solids (AIS), largely composed of pectins and other cell wall materials, were significantly higher in juice vesicles that were granulated. The results suggest that storage itself was not responsible for the marked accumulation of AIS in granulated juice vesicles. Rather, some interaction of fruit size with maturation, as well as other factors such as tree age and rootstock, likely contributed to the development of granulation.

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On-site and in situ bioremediation of wood-preservative contaminated groundwater

Water Science & Technology ◽

10.2166/wst.2000.0537 ◽

2000 ◽

Vol 42 (5-6) ◽

pp. 371-376 ◽

Cited By ~ 11

Author(s):

J.A. Puhakka ◽

K.T. Järvinen ◽

J.H. Langwaldt ◽

E.S. Melin ◽

M.K. Männistö ◽

...

Keyword(s):

Iron Oxidation ◽

Wood Preservative ◽

Pilot Scale ◽

High Rate ◽

Contaminated Groundwater ◽

Groundwater Temperature ◽

In Situ Bioremediation ◽

Contaminated Aquifer ◽

Fluidized Bed Process

This paper reviews ten years of research on on-site and in situ bioremediation of chlorophenol contaminated groundwater. Laboratory experiments on the development of a high-rate, fluidized-bed process resulted in a full-scale, pump-and-treat application which has operated for several years. The system operates at ambient groundwater temperature of 7 to 9°C at 2.7 d hydraulic retention time and chlorophenol removal efficiencies of 98.5 to 99.9%. The microbial ecology studies of the contaminated aquifer revealed a diverse chlorophenol-degrading community. In situ biodegradation of chlorophenols is controlled by oxygen availability, only. Laboratory and pilot-scale experiments showed the potential for in situ aquifer bioremediation with iron oxidation and precipitation as a potential problem.

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