N.J. Admin. Code § 7:9D-3.2

Current through Register Vol. 56, No. 21, November 4, 2024

Section 7:9D-3.2 - Specific requirements for the decommissioning of dewatering wells and dewatering wellpoints

(a) Any dewatering well constructed into confined aquifers shall be decommissioned only by a New Jersey master, journeyman or journeyman (Class B) well driller in accordance with N.J.A.C. 7:9D-3.1.

(b) Decommissioning of all other dewatering wells and dewatering wellpoints shall be performed by the licensed well driller of the proper class and shall be completed within five business days after the dewatering well or dewatering wellpoint is taken out of service.

(c) The well driller shall obtain written approval from the Department prior to instituting any modification in the decommissioning procedures. Applications shall be submitted pursuant to N.J.A.C. 7:9D-1.17.

(d) For all dewatering wells 25 feet or less in depth, that have not penetrated a confining layer, decommissioning shall be completed by employing one of the following methods:

1. If backfilling of the borehole is utilized:

i. Backfilling the hole with clean native materials;

ii. Tamping the backfill materials in layers to within several feet below proposed finished grade;

iii. Placing a minimum of a three foot concrete plug; and

iv. Backfilling the remaining portion of the hole with top soil or native soil materials; or

2. If decommissioning with an approved grout material, the decommissioning of the dewatering well or dewatering wellpoint shall be completed in accordance with 7:9D-3.1.

(e) If the casing and screen are completely removed from a dewatering well which is greater than 25 feet in depth but has not intersected a confining layer, the top 25 feet of the original borehole shall be cleared of all obstructions or drilled out to allow for the placement of a grout plug in accordance with 7:9D-3.1.

(f) If the casing and screen are left in place in a dewatering well greater than 25 feet in depth which has not penetrated a confining layer, the entire well/hole shall be decommissioned from the bottom of the well to the top in accordance with N.J.A.C. 7:9D-3.1. In order to prevent surface contamination from entering any annular space which has been gravel packed, the top 25 feet of the gravel pack and casing shall be removed to allow for the placement of a grout plug in accordance with N.J.A.C. 7:9D-3.1.

(g) Dewatering wells penetrating bedrock shall have that part of the well drilled into the bedrock formation sealed with neat cement grout. The balance of the hole shall be sealed in accordance with 7:9D-3.1, as applicable.

N.J. Admin. Code § 7:9D-3.2

Amended by 50 N.J.R. 171(a), effective 1/2/2018