7 Del. Admin. Code § 7301-10.0
Current through Register Vol. 28, No. 3, September 1, 2024
Section 7301-10.0 - Well Sealing10.1 General Requirements10.1.1 The sealing of a well shall be performed only be a Delaware licensed well driller or well driver.10.1.2 Within 30 days of the sealing of a well the water well contractor shall submit a well sealing report to the Department, in a format provided by the Department. The report shall be completed and signed by the well driller or well driver supervising the site work.10.1.3 The Department may require any well owner to have a well properly sealed if the Department determines that any of the following conditions apply: 10.1.3.1 The well has been abandoned or determined of no beneficial use or10.1.3.2 The well interferes with the withdrawal of a prior water user unless compensation for such interference is provided to the satisfaction of the Department, or10.1.3.3 The well is causing or is a potential source of contamination to waters of the State, or10.1.3.4 The well is having an adverse influence of waters of the State, or10.1.3.5 The well is deemed a potential safety hazard to the health and welfare of humans or animals, or10.1.3.6 The well is not constructed in accordance with the permit conditions or these Regulations, or10.1.3.7 The well was installed illegally.10.1.4 A well that interconnects aquifers shall be sealed unless otherwise approved by the Department.10.1.5 The Department may require or approve specific sealing procedures.10.1.6 The Department may require prior notification of the date of sealing.10.1.7 All wells being replaced, with the exception of public wells, shall be sealed within 15 days of completion of the replacement well unless approval for retaining the replaced well is granted by the Department pursuant to subsection 3.11 . Public wells shall be sealed within 30 days of completion of the replacement well.10.1.8 Wells that are unsuitable for their intended use shall be sealed pursuant to subsection 10.3 or reclassified pursuant to subsection 3.11.10.1.9 A well will not be considered sealed if only the supply line is sealed.10.2 Sealing and Fill Materials 10.2.1 Only concrete, Portland cement, sodium-based bentonite clay, or combinations of these materials or other materials approved by the Department shall be used to seal a well.10.2.2 Only drill cuttings, clay, silt, sand, gravel, and crusher run are considered acceptable fill material and may only be used pursuant to subsections 11.3 .6, 11.3.7, or 11.3.8.10.2.3 Portland cement grout and sodium-based bentonite clay grout shall meet the requirements pursuant to subsections 5.8 .12.1 or 5.8.12.2.10.3 Sealing Procedures 10.3.1 Prior to sealing, the well driller or well driver shall determine the condition of the well, its construction, and obstructions that may interfere with sealing. Obstructions shall either be removed or eliminated through the process of over-drilling, if necessary.10.3.2 Well casing not to be removed shall be cut off at or below grade.10.3.3 The Department may require that the well casing be ripped, perforated, or removed entirely to ensure that any previously un-grouted annular space or voids are filled with sealing materials.10.3.4 All wells shall be sealed with the appropriate sealing materials by pressure grouting through a tremie pipe from the bottom of the well upward to the ground surface, except as noted in subsections 10.3 .6, 10.3.7, or 10.3.8 unless otherwise approved by the Department.10.3.5 When Portland cement grout or concrete is used as a sealing material, it shall be emplaced in one continuous operation until grout returns to the surface.10.3.6 A dug well larger than 24 inches in diameter shall be filled and sealed by placing fill material in the well to a level approximately five feet below land surface, and placing sealing material above the fill. The top one foot of the well may be covered with fill material.10.3.7 For wells penetrating fractured or cavernous rock, coarse fill materials may be used to fill the cavernous portions of the well. The well shall be sealed from the bottom of the well to the cavernous zone and from the top of the cavernous zone to the land surface.10.3.8 Dewatering wells and shallow monitoring or observation less than 20 feet deep and two inches in diameter shall have the entire casing removed unless otherwise approved by the Department. After removal of the casing, the wells shall be sealed or filled with drill cuttings.10.3.9 Soil borings or uncased wells less than 20 feet deep shall be sealed or filled with drill cuttings or bentonite or cement grout.7 Del. Admin. Code § 7301-10.0
20 DE Reg. 180 (9/1/2016) (Final)