(a) At closure, the owner or operator must:
(1) remove or decontaminate all waste residues, contaminated
containment system components (liners, etc.) contaminated subsoils, and structures
and equipment contaminated with waste and leachate, and manage them as hazardous
waste unless 40 Code of Federal Regulations (CFR) §261.3(d) applies;
or
(2) eliminate free liquids by removing liquid wastes or solidifying
the remaining wastes and waste residues; stabilize remaining wastes to a bearing
capacity sufficient to support final cover; and cover the surface impoundment
with a final cover designed and constructed to:
(A) provide long-term minimization of the migration of liquids
through the closed impoundment;
(B) function with minimum maintenance;
(C) promote drainage and minimize erosion or abrasion of the
final cover;
(D) accommodate settling and subsidence so that the cover's
integrity is maintained; and
(E) have a permeability less than or equal to the permeability
of any bottom liner system or natural subsoils present.
(b) If some waste residues or contaminated materials are left
in place at final closure, the owner or operator must comply with all post-closure
requirements contained in 40 CFR §§264.117 - 264.120, including
maintenance and monitoring throughout the post-closure care period (specified
in the permit under 40 CFR §264.117). The owner or operator must:
(1) maintain the integrity and effectiveness of the final cover
including making repairs to the cap as necessary to correct the effects of
settling, subsidence, erosion, or other events;
(2) maintain and monitor the leak detection system in accordance
with 40 CFR §§264.221(c)(2)(iv) and (3) and 264.226(d), and comply
with all other applicable leak detection system requirements of this subchapter;
(3) maintain and monitor the groundwater monitoring system
and comply with all other applicable requirements of §§335.156 -
335.166 of this title (relating to Applicability of Groundwater Monitoring
and Response; Required Programs; Groundwater Protection Standard; Hazardous
Constituents; Concentration Limits; Point of Compliance; Compliance Period;
General Groundwater Monitoring Requirements; Detection Monitoring Program;
Compliance Monitoring Program; and Corrective Action Program); and
(4) prevent run-on and run-off from eroding or otherwise damaging
the final cover.
(c) If an owner or operator plans to close a surface impoundment
in accordance with subsection (a)(1) of this section, and the impoundment
does not comply with the liner requirements of §335.168(a) of this title
(relating to Design and Operating Requirements (Surface Impoundments)) and
is not exempt from them in accordance with §335.168(b) of this title,
then:
(1) the closure plan for the impoundment under 40 CFR §264.112
must include both a plan for complying with subsection (a)(1) of this section
and a contingent plan for complying with subsection (a) (2) of this section,
in case not all contaminated subsoils can be practicably removed at closure;
and the owner or operator must prepare a contingent post-closure plan under
40 CFR §264.118 for complying with subsection (b) of this section, in
case not all contaminated subsoils can be practicably removed at closure;
(2) the cost estimates calculated under 40 CFR §264.142
and §264.144 for closure and post-closure care of an impoundment subject
to this subsection must include the cost of complying with the contingent
closure plan and the contingent post-closure plan, but are not required to
include the cost of expected closure under subsection (a)(1) of this section.
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Source Note: The provisions of this §335.169 adopted to be effective May 28, 1986, 11 TexReg 2347; amended to be effective February 26, 1996, 21 TexReg 1142; amended to be effective November 15, 2001, 26 TexReg 9135 |