Methods and systems for in situ temporary containment of shallow contaminated soils

Patent metadata

Field	Value
Publication number	US-10399130-B2
Application number	US-201615744358-A
Country	US
Kind code	B2
Filing date	Jul 18, 2016
Priority date	Jul 22, 2015
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A method for installing an in situ, low-permeability temporary horizontal barrier at depth for vertical containment of a soil mass including installing a low permeability vertical barrier having walls located to contain a predetermined soil volume, the vertical barrier having a horizontal surface area in a plane perpendicular to its walls; and injecting low permeability reagents capable of forming a temporary horizontal barrier in a pattern suitable for creating a horizontal subsurface barrier joined to all of the vertical barrier walls to form an in situ barrier.

First claim

What is claimed is:

1. A method for installing an in situ, low-permeability temporary horizontal barrier at a depth for vertical containment of a soil mass, the method comprising:
installing a low permeability vertical barrier having a plurality of walls located to contain a predetermined soil volume, the vertical barrier having a horizontal surface area in a plane perpendicular to its walls;
injecting low permeability reagents capable of forming the in situ, low-permeability temporary horizontal barrier in a pattern suitable for creating a horizontal subsurface barrier joined to all of the vertical barrier walls to form the in situ low-permeability barrier; and
removing the in situ, low-permeability temporary horizontal barrier through application of a solution capable of dissolving the barrier.

2. The method of claim 1 further comprising implementing quality assurance and validation procedures after installation of the in situ, low-permeability barrier.

3. The method of claim 1 further comprising implementing remediation procedures.

4. The method of claim 1 further comprising site monitoring.

5. The method of claim 1 wherein the horizontal barrier degrades in a predefined duration due to environmental conditions.

6. The method of claim 1 wherein the low permeability reagents capable of forming the in situ, low-permeability temporary horizontal barrier are selected from the group consisting of sodium bentonite, enzyme-induced calcite precipitation, biopolymers, guar, microorganisms, vegetable oil, polysaccharide polymers, and xanthan gum.

7. The method of claim 1 wherein installing the vertical barrier comprises horizontal or direction drilling.

8. A system for installing an in situ, low-permeability temporary horizontal barrier for vertical containment of soil contaminants, the system comprising:
a low permeability vertical barrier having a plurality of walls located to contain a predetermined soil volume, the vertical barrier having a horizontal surface area in a plane perpendicular to its walls;
an injection tool including an injection channel and a plurality of distribution ports for boring into the predetermined soil volume and injecting low permeability reagents capable of forming the in situ, low-permeability temporary horizontal barrier to create a horizontal subsurface barrier joined to all of the vertical barrier walls to form an in situ barrier; and
removing the in situ, low-permeability temporary horizontal barrier through application of a solution capable of dissolving the barrier.

9. The system of claim 8 further comprising implementing quality assurance and validation procedures after installation of the in situ, low-permeability temporary horizontal barrier.

10. The system of claim 8 further comprising implementing remediation procedures including the injection and mixing of remediation agents in the treatment zone during placement and/or retrieval of the injection tool.

11. The system of claim 8 further comprising site monitoring.

12. The system of claim 8 wherein the horizontal barrier degrades due to environmental conditions.

13. The system of claim 8 wherein the low permeability reagents capable of forming the in situ, low-permeability temporary horizontal barrier are selected from the group consisting of sodium bentonite, enzyme-induced calcite precipitation, biopolymers, guar and xanthan gum.

14. The system of claim 13 wherein the reagent comprises sodium bentonite having a dosage in solution in the range of 10% w/v to 20% w/v.

15. The system of claim 13 wherein the reagent comprises xanthan gum having a dosage in solution in the range of 0.1% w/v to 1.0% w/v.

16. The system of claim 13 wherein the reagent comprises guar gum having a dosage in solution in the range of 0.5% w/v to 3.0% w/v.

Assignees

• Univ Arizona State
• Chevron Usa Inc

Inventors

• Halden Rolf U
• Kavazanjian Edward
• Jenck Alizee M
• Hamdan Nasser
• Hoelen Thomas

Classifications

• B09C1/00 Primary

  Reclamation of contaminated soil · CPC title

• E02D2600/20

  comprising details of connection between elements · CPC title

• E02D2250/003

  Injection of material · CPC title

• C08B37/0033

  Xanthan, i.e. D-glucose, D-mannose and D-glucuronic acid units, saubstituted with acetate and pyruvate, with a main chain of (beta-1,4)-D-glucose units; Derivatives thereof · CPC title

• E02D31/002

  Ground foundation measures for protecting the soil or subsoil water, e.g. preventing or counteracting oil pollution (not used, see subgroups and E02D31/00) · CPC title