(a) System requirements.

1. (1) Leachate collection systems shall be designed and installed to facilitate dewatering of the waste mass and disposal area.
2. (2) The systems shall be designed to limit the maximum leachate head on the bottom liner at any point at any time to thirty centimeters (30 cm) (twelve inches (12”)) or less.
3. (3) The system shall also be designed to facilitate maintenance.

(b) Drainage layer.

1. (1)

   1. (A) The leachate collection system shall consist of a permeable drainage layer with a minimum hydraulic conductivity of 1 x 10^-3 cm/sec or greater over the top of the liner system with a system of pipes and trenches at lower portions of the disposal areas which transmit leachate to a point or location for removal.
   2. (B) The system shall include provisions for the rapid removal and storage of leachate such as storage tanks, ponds, or treatment facilities.
   3. (C) Loading or discharge stations shall be provided as necessary.

2. (2)

   1. (A) Granular materials used in the leachate collection system shall be free of organic material and contain less than five percent (5%) by weight which passes the #200 sieve.
   2. (B) The use of carbonate rock for leachate collection systems should be avoided, especially where low pH leachates are anticipated.
3. (3) Alternative drainage layer materials or conductivities may be approved upon adequate demonstration that the drainage layer will otherwise meet the requirements of this section.

(c) Collection system design and documentation.

1. (1) The plans and design narrative should fully show and describe the leachate collection system and method of management.
2. (2) Calculations or demonstrations should be provided to show that the collection system will adequately dewater the waste mass and that clogging of the system will not occur.

(d) Collection pipe design.

1. (1) Leachate collection pipes shall be minimum six inches (6”) in diameter, must be chemically compatible with leachate, and structurally capable of supporting the maximum static and dynamic load anticipated from the overlying fill material and construction equipment, and it shall be demonstrated that the pipe has sufficient strength to resist crushing.
2. (2) Perforations shall be designed so as to minimize clogging.
3. (3) The pipe shall be laid on a sufficient slope to ensure adequate flow to the riser or manhole after consideration of potential future settling or consolidation of the landfill bottom.

(e) Leachate manhole/riser design.

1. (1) Leachate collection manholes or risers shall be located to prevent potential damage by landfill equipment.
2. (2) Manholes and risers will be constructed from materials of sufficient thickness to prevent crushing or deformation due to uneven loading during landfilling operations.

3. (3)

   1. (A) Penetration of the liner system by leachate collection pipes is discouraged.
   2. (B) If it is necessary to extend leachate collection pipes through a liner system, the methods used to seal the penetration must be described and detailed.

(f) Existing leachate removal systems.

1. (1)

   1. (A) The requirements of this subsection apply to the operation and upgrades of leachate removal systems installed prior to the effective date of this part.
   2. (B) The design of new systems shall be in accordance with subsection (g) of this section.
2. (2) General requirements. A positive method of leachate extraction shall be provided from the collection system in order to assure compliance with the head limitations of subsection (a) of this section.

3. (3)

   1. (A) Automatically activated pumps with preset elevations to turn the pumps on and off are preferred but not required.
   2. (B) Manually activated pumps or pumping systems may be used if some means to measure and limit leachate head level is approved and implemented.
   3. (C) If the facility cannot demonstrate that it can consistently maintain the required head level, automatic pumps shall be installed.

4. (4)

   1. (A) The facility shall address operation of the leachate collection system during the post-closure period in the facility design and operating narrative.
   2. (B) While an automatic system may not be required during the active phase, it may be required during the post-closure phase.
5. (5) Any modification of the removal systems or equipment replacement after the effective date of this part shall be in accordance with the requirements of subsection (g) of this section.

(g) New leachate removal systems.

1. (1) The requirements of this subsection apply to leachate removal systems installed after the effective date of this part.

2. (2) General requirements.

   1. (A) A positive means for the rapid removal of leachate from the collection system shall be provided to assure compliance with the head limitations of subsection (a) of this section.
   2. (B) Leachate removal systems, whether gravity flow or pumped flow systems, shall be designed for the anticipated peak flow.
   3. (C) Failure alarm systems, back-up equipment, and contingency plans shall be provided as necessary to assure reliability.

3. (3) Gravity flow systems.

   1. (A) Where the design provides for gravity flow of leachate from the collection system to storage tanks or treatment units, adequate peak flow storage shall be provided to assure continual removal of leachate.
   2. (B) Visual high water alarms on the tank may be required and at least two (2) days’ peak flow storage should be provided above the high water alarm.

4. (4) Pump systems.

   1. (A) Where the design provides for pumping of leachate from the collection system to storage tanks or treatment units, pumps shall be designed to handle the anticipated peak flow.
   2. (B) Dual, alternating pumps installed in the wetwell are required, or for small systems, a portable backup pump may be provided.
   3. (C) Visual high water alarms shall be provided.

5. (5) Storage tanks.

   1. (A) Tanks shall be provided with adequate peak and reserve storage for the expected removal frequency.
   2. (B) A means to easily measure daily leachate levels shall be provided as well as visual high water indicator or alarm system.

6. (6) Safety and maintenance features.

   1. (A) Automatic systems should be designed with alarms and trouble lights to indicate the need for servicing, as well as automatic cutoff devices to prevent overfilling of storage tanks and to prevent pumps from running dry unless they are designed to run dry.
   2. (B) Sufficient spare parts should be maintained at the site or contingency plans should be made in the event of failure.

(h) Secondary containment outside lined areas.

1. (1) Storage tanks and piping external to the lined area should be provided with secondary containment.
2. (2) Storage ponds must be lined similar to the disposal area.
3. (3) If storage ponds are utilized, some means of aeration should be provided to prevent odors.

(i) On-site leachate treatment.

1. (1) If the owner or operator proposes to treat leachate on site prior to disposal, the treatment system design shall be submitted for approval.
2. (2) The owner or operator shall demonstrate that the facility has the appropriate discharge permits.

(j) Certification.

1. (1) Construction of leachate collection systems shall be certified in the same manner as liner or cover systems.
2. (2) Construction documentation may be submitted with the liner construction documentation report, 8 CAR § 60-428(i).

3. (3) "As constructed" features for leachate collection systems shall be included with other cell construction features in the liner certification report and shall include the following:

   1. (A) Leachate collection pipe size, type, horizontal and vertical locations, and slope;
   2. (B) Leachate collection trench and sump locations with elevations;
   3. (C) Manhole or riser locations with top and invert elevations;
   4. (D) Leachate pump station locations and elevations of the bottom of the wetwell, inlet invert, pump on, and pump alarm;
   5. (E) Location and description of leachate storage tanks and other handling facilities; and
   6. (F) In addition, the certifying professional shall certify that the leachate system was constructed in accordance with the permit drawings and narrative.

(k) Leachate management and disposal.

1. (1) The narrative shall also describe the proposed means of leachate management.

2. (2) The narrative shall describe the method or methods of disposal and include the following:

   1. (A)

(i) If disposal is to a sanitary sewer system either by trucking or a direct connection, the receiving system must have the means to evaluate the effect of the discharge to ensure that it will not inhibit or disrupt either its collection or treatment system.

1. (ii) Copies of new or revised permits should be included with engineering inspection reports;

   1. (B) If a facility proposes to use leachate recirculation as its primary means of leachate management, it shall also obtain an agreement with a disposal facility in the event that recirculation does not prove effective;

   2. (C)

      1. (i) If leachate recirculation is the proposed management method, the facility shall, in addition to meeting the requirements of 8 CAR § 60-420, describe in detail how leachate will be removed and reintroduced into the waste mass.
      2. (ii) The description shall include:

(b) (b) The specific means and control methods for incorporating the leachate into the waste mass;

1. (c) (c) Odor control methods; and

   1. (d) (d) Worker protection measures.

      1. (iii) In addition, contingency plans as described in subdivision (k)(2)(B) of this section shall be provided;

   2. (D) Leachate may be land applied only after express approval or permitting by the Division of Environmental Quality and provided that the applicant can demonstrate a beneficial use resulting from the practice.

      1. (l) Leachate screening and monitoring.
2. (1) Each landfill required to install leachate collection systems shall test representative samples of leachate for each of the ground water monitoring parameters required under Subpart 12 of this part, Ground Water Monitoring and Corrective Action, or by permit conditions.

3. (2) Sampling parameters, frequencies, and locations shall be determined based on the character and quantity of leachate produced and the following requirements:

   1. (A) Sampling parameters. The initial sampling parameters shall include:

      1. (i) Appendix 1 constituents for Class 1 landfills;
      2. (ii) Appendix 2 constituents for landfills required to implement an assessment monitoring program pursuant to 8 CAR § 60-1205;
      3. (iii) Appendix 3 constituents for Class 3 landfills or an appropriate subset of constituents based on waste characteristics data; or
      4. (iv) An appropriate subset of constituents selected from Appendix 1 for other facilities required to monitor leachate quality;
   2. (B) Adjustment to sampling parameters. The Director of the Division of Environmental Quality may approve the deletion of sampling parameters where analytical data indicates a constituent has not historically been detected and is not reasonably expected to be present in the leachate, however, periodic resampling for the full constituent list may be required to confirm consistent leachate characteristics;

   3. (C) Sampling frequency.

      1. (i) The initial sampling frequency shall be at the same frequency required under Subpart 12 of this part for ground water monitoring.
      2. (ii) Sampling frequency may be adjusted as follows:

(b) (b) The director may decrease the sampling frequency where historical data indicates little variation in the concentration of detected constituents; and

1. (D) Sampling locations. Sampling locations shall be selected that will produce representative samples of the leachate quality generated by the landfill.

   1. (m) Leachate disposal testing.
2. (1) Leachate testing requirements shall be determined by the division based on the character and quantity of leachate produced and the ultimate disposal method.
3. (2) Where disposal of leachate is to a publicly owned treatment works, leachate disposal testing requirements shall conform to any division-approved pretreatment programs and procedures.
4. (3) Prior to acceptance of leachate for treatment, publicly or privately operated treatment works that are not required to implement and operate pretreatment programs shall obtain division approval.

5. (4) Treatment works operators shall demonstrate that:

   1. (A) The facility is permitted under the National Pollutant Discharge Elimination System and that acceptance of the leachate would be in compliance with permit provisions;
   2. (B) Adequate treatment capacity and capability is available; and
   3. (C) An adequate testing program is in place to assure that only nonhazardous leachate is accepted for treatment and disposal and the leachate is of a concentration and character that is amenable to treatment.

6. (5)

   1. (A) If leachate recirculation is the primary management means, the facility shall perform at a minimum an annual Toxicity Characteristic Leaching Procedure analysis of the recirculated leachate.
   2. (B) Leachate exhibiting hazardous characteristics as defined by Hazardous Waste Management, 8 CAR pt. 81, when not recirculated as described in subdivision(k)(2)(C) of this section, above, and 8 CAR § 60-420, shall be managed and disposed of as a hazardous waste in accordance with 8 CAR pt. 81.

(n)

1. (1) The requirements of this section are considered minimum requirements only.
2. (2) Special cases not addressed by this section may be considered by the division on a case-by-case basis and the division reserves the right to request additional testing if necessary to protect human health and the environment.