Alaska Administrative Code
Title 18 - Environmental Conservation
Chapter 63 - Siting of Hazardous Waste Management Facilities
Article 2 - Requirements for Hazardous Waste or PCB Incinerators, Hazardous Waste Land Facilities, Chemical Waste Landfills, and Hazardous Waste Underground Injection Wells
18 AAC 63.120 - Geotechnical information required for hazardous waste land facilities and chemical waste landfills
Current through February 27, 2024
(a) In addition to the other applicable requirements of this chapter, each application for a hazardous waste land facility or chemical waste landfill must also include a proposed groundwater monitoring program that meets the requirements of
(b) An application for a hazardous waste land facility or chemical waste landfill must also include a geotechnical report that contains
(c) To conduct the tests and collect the data required under (b) of this section, not less than one subsurface boring must be made in proposed active portions for each hectare or portion of a hectare. Boring information may be supplemented with geophysical testing, such as resistivity, seismic refraction, and gravity surveys. Where feasible, borings must be located so that there is a minimum of one boring for each major geomorphic feature, such as a ridge, a lowland, or drainage swale, and all borings must extend not less than 30 meters below the anticipated bottom elevation of any installed or constructed liner.
(d) At each boring required under (c) of this section, representative substrate or rock samples must be collected from each geologic layer, or every two meters, whichever is less, using either Shelby-tube or split-spoon samplers. If a significant change in lithology, such as bedrock or frozen substrate, is encountered within the boring depth specified, continuous rotary-cut core samples must be collected and field identified. Refrigerated, freezing-point-depressed fluids approved by the department must be used for the coring of frozen rock or substrate. Field identifications of bedrock samples must be verified by laboratory inspection of hand specimen and thin section. Test holes must be cased and abandoned holes plugged in such a way as to preclude the possibility of having them conduct hazardous waste to the subsurface. Estimates of rock porosity must be made. Samples must be tested for
(e) Permeability of rock under (d)(5) of this section must be determined by a method that adequately accounts for the presence of joints and fractures; permeability of frozen substrate or rock must be determined only by procedures that have been approved in advance by the department. Samples collected for determination of permeability by the triaxial cell method must be collected by the standard undisturbed 7.6 centimeter diameter Shelby-tube soil sampling technique; nonstandard sampler and hammer combinations may be used as appropriate in coarse granular substrate.
Authority:AS 46.03.020
AS 46.03.313