Hawaii Administrative Rules
Title 11 - DEPARTMENT OF HEALTH
Subtitle 1 - GENERAL DEPARTMENTAL PROVISIONS
Chapter 23 - UNDERGROUND INJECTION CONTROL
Section 11-23-10 - Provision for artesian aquifer protection
Current through February, 2024
(a) Where an injection well is located in a caprock formation which overlies volcanic USDW under artesian pressure, the following conditions shall be applied:
(b) The locations of artesian aquifer areas are described generally. The major areas, which have an extensive caprock formation, include:
Other artesian aquifer areas are found in Valleys, where alluvium or other sedimentary material has been deposited to significant depths.
(c) If the ratio of the depth of the proposed injection well, to the estimated depth of caprock less fifty feet, is 1:2 or less, the applicant need not extend the depth of the injection well or wells in order to verify caprock thickness, prior to completion at the shallower proposed depth. The department shall estimate the depth of caprock by comparing lithology from logs of borings in the vicinity. If, however, artesian aquifer conditions are encountered, the applicant shall have the options as set forth in subsection (f). The following is a table showing the depths needed to achieve the 1:2 ratio:
Proposed depth of injection well: |
10 |
15 |
20 |
25 |
30 |
40 |
50 |
60 |
70 |
80 |
90 |
100 |
Minimum depth of caprock: |
70 |
80 |
90 |
100 |
110 |
130 |
150 |
170 |
190 |
210 |
230 |
250 |
(d) If the ratio of the depth of the proposed injection well, to the estimated depth of caprock less fifty feet, is greater than 1:2, the applicant shall have the depth of the injection well temporarily extended by fifty feet to verify that artesian aquifer conditions are not encountered within that r"nge. The fifty feet of extended hole shall be properly sealed by the tremie method, with a cement slurry that contains no more than five gallons of water per ninety-four pound sack of cement.
(e) Where a test well is planned for either a Single injection well or a multiple well field, the depth of the test well shall be extended fifty feet into confining materials beyond the proposed depth of the deepest well. If the test well is intended to be operational, the lower fifty feet shall be properly sealed as detailed in subsection (d) of this section.
(f) Where artesian aquifer conditions are unexpectedly encountered, the applicant may choose to: