Laserfiche WebLink
the movement of poor-quality water, pollutants, or contaminants through <br />the destroyed well structure. <br />Material to be extracted from the original borehole shall be removed by <br />means of drilling, including overdrilling, if necessary. The enforcing agency <br />should be contacted to determine requirements for proper disposal of <br />removed materials. <br />Casing, filter pack, and annular seal materials may be left in place during <br />sealing operations, if the enforcing agency agrees they cannot or should not <br />be removed. In such a case, appropriate sealing material shall be placed in <br />the well casing, filter pack, and all other significant voids within the entire <br />well boring. Casing left in place may require perforation or puncturing to <br />allow proper placement of sealing materials. Sealing material may have to be <br />applied under pressure to ensure its proper distribution. <br />c.Monitoring wells shall, at a minimum, be destroyed in accordance with the <br />requirements of Section 23 of the Water Well Standards if located in an area <br />free of any known or potential contamination or pollution. <br />B. <br />Exploratory Borings. Exploratory borings shall be completely filled with appropriate sealing <br />material from bottom to top, if located in areas of known or suspected contamination or <br />pollution. Borings located outside such areas shall, at a minimum, be filled with sealing <br />material from ground surface to the minimum depths specified in Section 23 of the Water Well <br />Standards. Additional sealing material shall be placed below the minimum surface seal where <br />needed to prevent the interchange of poor-quality water, pollutants, or contaminants between <br />strata penetrated by the boring. <br />Appropriate fill or sealing material shall be placed below and between intervals containing <br />sealing material. Sealing material is often economical to use as fill material. <br />The boring shall be inspected immediately prior to filling and sealing operations. All <br />obstructions and pollutants and contaminants that could interfere with filling and sealing <br />operations shall be removed prior to filling and sealing. The enforcing agency shall be notified <br />as soon as possible if pollutants or contaminants are known or suspected to be in a boring to <br />be destroyed. Well destruction operations may then proceed only at the approval of the <br />enforcing agency. The enforcing agency should be contacted to determine requirements for <br />proper disposal of removed materials. <br />c.Placement of Material. The placement of sealing material for monitoring wells and exploratory <br />borings is generally described in Section 23 and Appendix B of the Water Well Standards. The <br />following additional requirements shall be observed when placing sealing material for <br />monitoring well or exploratory boring destruction. <br />1.Placement Method. The well or exploratory boring shall be filled with appropriate <br />sealing, and fill material where allowed, using a tremie pipe or equivalent, proceeding <br />upward from the bottom of the well or boring. <br />Sealing material shall be placed by methods (such as the use of a tremie pipe or <br />equivalent) that prevent freefall, bridging, and dilution of sealing materials, and/or <br />prevent separation of aggregate from sealants. Sealing material may be placed by <br />.-52-