Closure and Post-Closure Care: Closure Plans
(1)Two types of written closure plans shall be prepared:
(a)The two types of closure plan are:
(A)A conceptual “worst-case” closure plan, for closing the site at its maximum capacity. The plan shall contain sufficient detail to allow a reasonable estimate of the cost of closing the non-municipal land disposal site as required by OAR 340-095-0090 (Financial Assurance Criteria)(1)(a); and subsequently
(B)A Final Engineered Site Closure Plan, as required by OAR 340-095-0050 (Closure and Post-Closure Care: Closure Permits)(2)(a), which shall replace the conceptual “worst-case” closure plan.
(b)Schedule for preparation of closure plans:
(A)The conceptual “worst-case” closure plan shall be prepared and placed in the facility operations office or other location approved by the Department, and the Director shall be notified of that action no later than April 9, 1995 or by the initial receipt of waste, whichever is later;
(B)The Final Engineered Site Closure Plan shall be prepared and submitted to the Department five years before the anticipated final closure date, or at a date specified in the permittee’s closure permit pursuant to OAR 340-095-0050 (Closure and Post-Closure Care: Closure Permits)(2)(a).
(2)Requirements for closure plans. A closure plan shall specify the procedures necessary to completely close the non-municipal land disposal site at the end of its intended operating life:
(a)Requirements for the conceptual “worst-case” closure plan shall consist of at least the following:
(A)A description of the steps necessary to close all non-municipal land disposal units at any point during their active life;
(B)A description of the final cover system that is designed to minimize infiltration and erosion;
(C)An estimate of the largest area of the non-municipal land disposal unit ever requiring a final cover; and
(D)An estimate of the maximum inventory of wastes ever on-site over the active life of the facility.
(b)Requirements for the Final Engineered Site Closure Plan. In addition to the requirements for the conceptual “worst-case” closure plan, the Final Engineered Site Closure Plan shall consist of at least the following elements:
(A)Detailed plans and specifications consistent with the applicable requirements of OAR 340-093-0140 (Detailed Plans and Specifications Required) and 340-095-0030 (Design Criteria)(2), unless an exemption is granted as provided in OAR 340-093-0070 (Applications for Permits)(5);
(B)A description of how and when the non-municipal land disposal site will be closed. If a landfill, the description shall, to the extent practicable, show how the landfill will be closed as filling progresses to minimize the area remaining to be closed at the time that the site stops receiving waste. A time schedule for completion of closure shall be included;
(C)Details of final closure. If a landfill, details of final cover including soil texture, depth and slope;
(D)Details of surface water drainage diversion; and
(E)Other information requested by the Department necessary to determine whether the non-municipal land disposal site will comply with all applicable rules of the Department.
(3)Department approval. The Final Engineered Site Closure Plan is subject to written approval by the Department. After approval by the Department, the permittee shall implement the Final Engineered Site Closure Plan within the approved time schedule.
(4)Amendment of Plan. The approved Final Engineered Site Closure Plan may be amended at any time as follows:
(a)The permittee must amend the plan whenever changes in operating plans or facility design, or changes in OAR 340 divisions 93 through 97, or events which occur during the active life of the landfill significantly affect the plan. The permittee must also amend the plan whenever there is a change in the expected year of closure. The permittee must submit the necessary plan amendments to the Department for approval within 60 days after such changes or as otherwise required by the Department;
(b)The permittee may request to amend the plan to alter the closure requirements based on cause. The request must include evidence demonstrating to the satisfaction of the Department that:
(A)The nature of the non-municipal land disposal site makes the closure requirements unnecessary; or
(B)The requested alteration of closure requirements is necessary to prevent threat of adverse impact on public health, safety or the environment.
(c)The Department may amend a permit to require the permittee to modify the plan if it is necessary to prevent the threat of adverse impact on public health, safety or the environment. Also, the Department may alter the closure requirements based on cause.
Rule 340-095-0060 — Closure and Post-Closure Care: Closure Plans,