title: Improved slant drilling well for in situ remediation of groundwater and soil at contaminated sites.
abstract: Soil contamination has become a crucial issue in urban redevelopment. Japan has many contaminated sites on which manufacturing has been conducted over several decades. Site holders are now under pressure to manage chemical contamination; however, the use of heavy machinery is difficult in remedial operations on restricted sites, especially where there are still working factories. The slant well is a potentially useful technique in such settings, but its use is technically challenging because of the need for high drilling accuracy and the difficulty in sealing the slanted bores. In this study, we investigated an improved technique for slant drilling that can be used around existing structures to treat contaminated soil and groundwater. A key to this novel approach was the use of water-swelling materials as sealants. Research at a test site investigated the accuracy of drilling. Tracer tests were also conducted using sodium chloride and urea. The improved slant borings showed a deviation of less than 2% from the target bore. The spread of the two tracers at different depths was demonstrated. The proposed technique provides a useful approach to the treatment of brownfield sites in countries where in situ remediation has not yet been undertaken.
authors.affiliation: Takenaka Corporation, Research and Development Institute, 1-5-1 Ohtsuka, Inzai, Chiba, 270-1395, Japan. furukawa.yasuhide@takenaka.co.jp.|Yokohama National University, 79-1 Tokiwadai, Hotogayaku, Yokogama, 240-8501, Japan. furukawa.yasuhide@takenaka.co.jp.
authors.forename: Yasuhide
authors.identifier: http://orcid.org/0000-0003-0732-5142
authors.initials: Y
authors.lastname: Furukawa
authors.affiliation: Takenaka Corporation, Research and Development Institute, 1-5-1 Ohtsuka, Inzai, Chiba, 270-1395, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Mukai
authors.affiliation: Takenaka Civil and Engineering, 1-1-1 Shinsuna, Koutouku, Tokyo, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ohmura
authors.affiliation: Yokohama National University, 79-1 Tokiwadai, Hotogayaku, Yokogama, 240-8501, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kobayashi
mesh_terms: D052918:Environmental Restoration and Remediation / Q000379:methods*; D060587:Groundwater / Q000737:chemistry*; D007564:Japan; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical
keywords: Brownfield; In situ remediation; Slant drilling; Soil contamination