N.J. Admin. Code § 7:14A-8.14 - Specific operating criteria and construction standards applicable to Class II wells

(a) This section establishes operating criteria and construction standards for Class II wells.

(b) Construction requirements for Class II wells are as follows:

1. Class II wells shall, at a minimum, be constructed in accordance with the requirements and specifications set forth in N.J.A.C. 7:9D. More stringent requirements shall be imposed, based on an evaluation of the nature of the injection fluid and/or of geological conditions, or where the Department otherwise determines that it is appropriate, based on considering potential impacts on ground water quality.

2. All new Class II wells shall be sited in such a fashion that they inject into a formation which has confining zones that are free of open faults or fractures within the area of review.

3. All Class II injection wells shall be cased and cemented to prevent movement of fluids into or between underground sources of drinking water. The casing and cement used in the construction of each newly drilled well shall be designed for the life expectancy of the well. In determining and specifying casing and cementing requirements, the following factors shall be considered:

i. Depth to injection zone;

ii. Injection pressure, external pressure, internal pressure, and axial loading;

iii. Hole size;

iv. Size and grade of all casing strings (wall thickness, diameter, nominal weight, length, joint specifications, and construction material);

v. Corrosiveness of injected fluids, formation fluids and temperatures;

vi. Lithology of injection and confining zones; and

vii. Type and grade of cement.

4. Appropriate logs and other tests shall be conducted during the drilling and construction of new Class II wells. A descriptive report interpreting the results of these logs and tests shall be prepared by a qualified log analyst and submitted to the Department. At a minimum, these logs and tests shall include:

i. Deviation checks on all holes constructed by first drilling a pilot hole, and then enlarging the pilot hole by reaming or another method. Such checks shall be at sufficiently frequent intervals to ensure that vertical avenues for fluid movement in the form of diverging holes are not created during drilling; and

ii. Such other logs and tests as may be needed after taking into account the availability of similar data in the area of the drilling site, the construction plan, and the need for additional information that may arise from time to time as the construction of the well progresses. For surface casings and for intermediate and long strings of casings, the following logs shall be used:

(1) Resistivity, spontaneous potential, gamma ray and caliper logs before the casing is installed;

(2) A cement bond, temperature, or density log after the casing is set and cemented; and

(3) Fracture finder logs, when intermediate and long strings of casing are intended to facilitate injection.

5. At a minimum, the following information concerning the injection formation shall be determined or calculated for new Class II wells:

i. Fluid pressure;

ii. Temperature;

iii. Fracture pressure;

iv. Other physical and chemical characteristics of the injection zone; and

v. Physical and chemical characteristics of the formation fluids.

(c) Operating, monitoring, and reporting requirements for Class II wells are as follows:

1. Operating requirements shall, at a minimum, specify that:

i. Injection pressure at the well head shall not exceed a maximum which shall be calculated so as to ensure that the pressure in the injection zone during injection does not initiate new fractures or propagate existing fractures in the injection zone. In no case shall injection pressure initiate fractures in the confining zone or cause the movement of injection or formation fluids into an underground source of drinking water; and

ii. Injection between the outermost casing protecting underground sources of drinking water and the well bore is prohibited.

2. Monitoring requirements shall, at a minimum, include:

i. Monitoring of injected fluids at time intervals sufficiently frequent to yield data representative of the fluids' characteristics;

ii. Monitoring of injection pressure, flow rate, and cumulative volume with at least the following frequencies:

(1) Weekly for produced fluid disposal operations;

(2) Monthly for enhanced recovery operations;

(3) Daily during the injection of liquid hydrocarbons and injection for withdrawal of stored hydrocarbons; and

(4) Daily during the injection phase of cyclic steam operations;

iii. A demonstration of mechanical integrity pursuant to 7:14A-8.12(c) at least once every five years during the life of the injection well;

iv. Maintenance of the results of all monitoring until the next permit review; and

v. Hydrocarbon storage and enhanced recovery may be monitored on a field or project basis rather than on an individual well basis by manifold monitoring. Manifold monitoring may be used in cases of facilities consisting of more than one injection well, operating with a common manifold. Separate monitoring systems for each well may not be required provided the owner or operator demonstrates that manifold monitoring is comparable to individual well monitoring.

3. Reporting requirements shall, at a minimum, include: An annual report to the Department summarizing the results of the monitoring required under (c)2 above. Previously submitted information may be included by reference.

i. Owners or operators of hydrocarbon storage and enhanced recovery projects may report on a field or project basis rather than an individual well basis where manifold monitoring is used.

Notes

N.J. Admin. Code § 7:14A-8.14