Premium
A Nested‐Cell Approach for In Situ Remediation
Author(s) -
Luo Jian,
Wu Weimin,
Fienen Michael N.,
Jardine Philip M.,
Mehlhorn Tonia L.,
Watson David B.,
Cirpka Olaf A.,
Criddle Craig S.,
Kitanidis Peter K.
Publication year - 2005
Publication title -
groundwater
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 94
eISSN - 1745-6584
pISSN - 0017-467X
DOI - 10.1111/j.1745-6584.2005.00106.x
Subject(s) - in situ , environmental remediation , environmental science , computer science , chemistry , biology , contamination , ecology , organic chemistry
We characterize the hydraulics of an extraction‐injection well pair in arbitrarily oriented regional flow by the recirculation ratio, area, and average residence time in the recirculation zone. Erratic regional flow conditions may compromise the performance of the reactor between a single well pair. We propose an alternative four‐well system: two downgradient extraction and two upgradient injection wells creating an inner cell nested within an outer cell. The outer cell protects the inner cell from the influence of regional flow. Compared to a two‐well system, the proposed four‐well system has several advantages: (1) the recirculation ratio within the nested inner cell is less sensitive to the regional flow direction; (2) a transitional recirculation zone between the inner and outer cells can capture flow leakage from the inner cell, minimizing the release of untreated contaminants; and (3) the size of the recirculation zone and residence times can be better controlled within the inner cell by changing the pumping rates. The system is applied at the Field Research Center in Oak Ridge, Tennessee, where experiments on microbial in situ reduction of uranium (VI) are under way.