SECTION 252:515-25-32. Contents of closure plan

(a)   All disposal facilities. The closure plan for all disposal facilities shall include the following as a minimum:

(1)   identification of site-specific closure activities, a description of how each is expected to be performed, and a schedule for completing all activities;

(2)   calculation of closure cost estimates in accordance with Subchapter 27 of this Chapter;

(3)   an estimate of the maximum inventory of waste ever on-site over the active life of the facility;

(4)   detailed plans for:

(A)   identifying and removing from the site, all equipment, temporary buildings and other improvements not designated as permanent in the permit application;

(B)   reworking or replacing defective groundwater monitor wells, gas wells, and other defective monitoring equipment, if any;

(C)   monitoring ground and surface water, if required;

(D)   collecting and analyzing soil and water samples;

(E)   disposing of final wastes and affected soils;

(F)   decontamination of facility structures, if necessary;

(G)   maintaining site security and access control, if post-closure monitoring is required;

(H)   redesigning final closure in accordance with existing site conditions and applicable rules;

(I)   preparing final closure certification and other required documents and notices; and

(J)   performing any other tasks necessary to achieve final closure of the site.

(b)   Additional information for land disposal facilities. The closure plan for land disposal facilities shall include the following additional information:

(1)   an estimate of the largest area of the disposal facility ever requiring final cover during the active life;

(2)   a detailed description of the final cap design and construction, including:

(A)   a calculation of the amount of material needed for each phase of closure;

(B)   identification of the soil type to be used for the final cover, to include:

(i)   the location at which it will be obtained;

(ii)   an analysis of the proposed cover material's permeability;

(iii)   mass balance calculations to demonstrate sufficient soil is available;

(C)   provisions for obtaining, hauling, and placing the soil for final cover;

(D)   a description of the design and construction of final cover to meet the requirements of 252:515-19-53;

(E)   a description of the design and construction of gas vents or collection pipes to be incorporated in the cap design, if such structures are required;

(F)   the QA/QC methods to be used in cap construction and to document the final cover is built to specification; and

(G)   the schedule and method of placement of all components of the final cap;

(3)   plans for:

(A)   grading, planting, fertilizing and establishing vegetation for all disturbed areas, including reshaping and revegetation of both on-site and off-site soil borrow areas to blend with surrounding terrain, or another approved reclamation plan;

(B)   constructing surface drainage and erosion control measures or reworking existing measures as necessary;

(C)   installation of final cover;

(D)   fitting existing leachate collection systems with a method for automatic and continuous removal of leachate not requiring owner/operator intervention;

(E)   remedying all former improper closure or waste placement at the site; and

(F)   conducting the final closure survey and preparing the closure certification; and

(4)   a constructed map showing what the contours of the site will be at final closure.

(c)   Phased closure authorized. Individual disposal areas of a land disposal facility may be closed in phases.

(1)   Closure plan. A plan for phased closure shall be included as part of the closure plan.

(2)   Financial assurance reduction. To reduce financial assurance for each disposal area closed in a phased closure scenario, a certification prepared and sealed by an independent professional engineer licensed in the State of Oklahoma if the facility was permitted to serve a population of greater than 5,000, shall be provided to the DEQ. Such certification shall:

(A)   certify that the area was closed according to the approved closure plan, the permit, and applicable rules; and

(B)   contain a closure report with related drawings, plans or specifications describing how closure was performed.

(3)   DEQ approval. The DEQ must approve closure of the disposal area before financial assurance may be reduced.

[Source: Added at 20 Ok Reg 1151, eff 6-1-03; Amended at 34 Ok Reg 1199, eff 9-15-17]