vvEPA United States Environmental Protection Agency Office of Solid Waste and Emergency Response DIRECTIVE NUMBER: 9476.02(83) Interpretation of Closure and Post-Closure Re- quirements Regarding Hazardous Waste Treatment, Storage and Disposal Facilities APPROVAL DATE: i'11'83 EFFECTIVE DATE: i-11"83 ORIGINATING OFFICE: office of Solid Waste 0 FINAL D DRAFT CTATIIC STATUS: A- Pending OMB approval B- Pending AA-OSWER approval C- For review &/or comment. D- In development or circulating REFERENCE (other documents): headquarters [ ] [ ,- ] [ ] OS WER OS WER OS WER /£ DIRECTIVE DIRECTIVE D ------- PARTS 264 AND 265 SUBPART G - CLOSURE/POST-CLOSURE 'TOG: 9^76.02(83) Key Words: Closure, Final Cover, Liquid Wastes, Pose-Closure Regulations: 40 CFR Parts 264, 265, HSWA.201(c) Subject: Interpretation of Closure and Post-Closure Requirements Regarding Hazardous Waste Treatment, Storage and Disposal Facilities Addressee: Dr. Reva Rubenstein, Director, Institute of Chemical Wastes Management Association, National Solid Wastes Management Associa- tion, 1120 Connecticut Avenue, N.W., Washington, D.C. 20036 Originator: -John H. Skinner, Acting Director, Office of Solid Waste Source Doc: -#9476.02(83) • '''"'.' Date: ' •' ' 1-11-83 . Summary: Recontouring the final cover material and adjusting inplace waste in the. same unit as required to maintain the function of the final cover (as a result of subsidence and settlement) does not constitute receipt of hazardous waste after July 26, 1982 (HSWA). These actions must be approved as part of each facilityrs closure plan by the Regional Administrator. Modifications can be made with Agency approval. Controlled irrigation of the vegetative cover is allowed in order to establish vegetation during the closure period or to maintain it during pro- longed dry spells in the post-closure period. However, to provide long-term minimization of migration of liquids through the closed landfill and to func- tion with minimum maintenance, the plant species chosen should be indigenous, require little or no additional moisture, and be selected based on anticipated moisture, light, temperature, elevation, competitive cohabitants, etc. The closure and post-closure plans should contain a description of when and why irrigation may be necessary. The placement of bulk liquids in non-containerized liquid hazrdous waste, or free liquids contained in hazardous waste, is prohibited from any landfill after May 8, 1985 (HSWA §§ 201(c)). In addition, the following points must be emphasized: o Any liquid added to sustain vegetation cannot be a hazardous waste. o Liquids may not be injected into the waste after closure. o Liquids are not allowed during closure, after May 1985, including leachate recirculation. o The characteristics and purpose of any liquids to be added to the cover during or after closure must be specified in the closure or post-closure plans and approved by the RA or authorized State. Such purpose and extension must be consistent with the environmental objectives specified in Parts 264 and 265. Assuming an owner/operator completes the cell in a timely manner (i.e. within the 180-day closure period), landfills that are currently engaged in co-disposal of hazardous and non-hazardous wastes could continue to accept non-hazardous wastes after-July 26, 1982, in order to complete a partially ------- Continued from Document 9476.02(83) filled hazardous waste unit and close pursuant to Part 264 and 265 requirements. If the closure- cannot be completed within the 180-day closure period, the owner/operator must apply to have the period extended beyond six months, for a specified time period [see §§265.113(b) or 264.113(b)] to allow the waste to be filled until the designed elevation is reached. This type of closure could be approved if it provides for a more environmentally sound closure, and not merely for the economic convenience of the owner/operator. Where a surface impoundment receives no more hazardous wastes after July 26, 1982, but closure has not yet been effected, the waste may be removed from the surface impoundment, solidified and placed in the same impoundment to ensure 'that it •will-bear the weight of the cover. Assuming that this solidi- fying material is not a hazardous waste, EPA does not consider this replacement of waste (after January 25, 1983) to be "receipt" of hazardous waste which would constitute a "regulated unit." Where multiple hazardous waste trenches will cease to receive hazardous waste on or before July 26, 1982, and where the closure plan provides for a delayed closure of a half-filled trench for the deposit of solidified hazardous waste from closed and capped trenches, such placement of solidified hazardous . waste into the reserved half filled trench, even at the same facility, will be considered "receipt" of. hazardous waste. Therefore, the trench will constitute a "regulated" unit. This is because the waste is received and disposed of at the facility unit after July 26, 1982. Where landfills consist of a series of trenches which are separately lined, each trench is a separate waste management unit. The transfer of hazardous waste from one unit to another after July 26, 1982, therefore makes the receiving trench or unit a "regulated" unit. ------- JAN j I IS83 Dr. Reva Rubenstein Director .-...- Institute of Chemical waste ; ; .: . ' . ... ......... Management •'•'.. National Solid Wastes Management Association 1120 Connecticut Avenue, M.W. Washington, O.C. 20036 Dear Dr. Rubenstein: This letter is in response to your letter of December 6, 1982, requesting interpretation of closure and post-closure requirements regarding land disposal facilities. I have responded to your questions in the order presented in your letter and attachment. 1. . Recontouring the final cover material and/or adjusting ~ inplace waste in the same unit as required to maintain the function of the final cover as a result of.-subsidence and settlement, does not constitute receipt of hazardous waste after January 25, 1983.J These actions must be described in each facility's closure and post-closure plans which must be approved by the Regional Administrator. Modifica- tions can be made to these plans as- necessary- with Agency approval. 2. The controlled irrigation of the vegetative cover is allowed in order to establish vegetation during the closure period or to maintain it during prolonged dry spells in the post- closure period. But the regulations require the final cover to provide long-terra minimization of migration of liquids through the closed landfill (S264.'310(a) (1) ) , and to function with minimum maintenance (S264.310(a)(2)). Thus, the guidance documents recommend that the plant species chosen be indigenous, require minimal or no additional moisture, and be selected based on anticipated moisture, light, temperature, elevation, and competitive cohabitants, etc. ------- The closure and post-closure plans should contain a descrip- tion of why and when the irrigation may h*» determined to be necessary (e.g., recommended by local agrononisit to establish vegetation during- a dry period), the amount and frequency of water application, and water balance analysis showing the effect of the irrigation water on total annual liquid input through the final cover./ EPA has available two reports that provide technical information on this subject, entitled "Evaluating Cover Systems for Solid and Hazardous Waste" sw-867, September 1982, which discusses irrigation of plant cover and other plant requirements; and (2)."Hydrologic Simulation on Solid Waste. Disposal Sites". SW-868, September 1982, which is a computerized water balance model, to evaluate the probable hydrologic performance of existing or proposed landfill designs. Both of the reports are available from the Government Printing Office^ (SW-367 i« stock No. 055- 000-00228-2 «S4.75, SW-S68 is Stock No. 055-000-00225-8 $36.00). EPA is currently revising the model for "Hydrologic Simulation on Solid Waste Disposal sites" to enable its use in estimating seepage through the liner as well as through the cover. The revised model should be available early in 1983. Your statement that 40 CPK Parts 264 and 265 prohibit the addition of bulk liquids to the waste^ management unit ,1s not quite accurate. Bulk liquids^aVe^ 'afrlnfiefl "'i'r "itne' site is lined and has a leachate collection and "removal system. Liquids in the leachate collection system must be removed during operation, closure, and post-closure. In general, the addition of liquids into the unit during closure would be permitted only if by doing so the facility and waste will be stabilized sooner. As you know, the objective during and after closure is to remove liquids and keep them out. If liquids are added during closure, the closure period would need to be extended until the addition stopped. To further clarify the above explanations I must emphasize four points* First, any liquid applied to the final cover of a landfill to sustain vegetation cannot be a hazardous waste (e.g., cannot be leachate unless it is no longer a hazardous waste), cannot harm the vegetation, and cannot otherwise iapair the integrity of the final coyer (e.g., cause increased infiltration because of damage caused by pH). Second, liquids may not be injected into the waste after closure (e.g., leachate recirculation by injection), since this is contrary to the post-closure objective of keeping liquids out. Third, as stated aoove, liquids could be allowed during closure, including leachate ------- recirculaiion, id: (a) there is a liner and leachate collection system, (b) leachate is removed from the leachata collection system, (c) the addition of liquids serves Jtpjj* njiariJCLa."closure~Te.g. , accelerates subsidence -end" Ytab ill sat ion P/~ r^JLh.er jyiajT_jnQrely serves as a__cpnveniant way to dispose of thjTl'iqu id a, ~anH~T d ) tn e liquid addition ia explained ^aad "luatitied in the cl.Qaugg_glan. .Such Saure would not be completed _unti_l _recircu^a_tion__c:ea.8e8j Also/ recircuiaTion ot a~ hazardous waste (leachate) after Tanuary 26, 1983 vould make the unit a regulated uni£ subject to tha requirements of Part 264._ I should point out that racirculatio'n of a hazardous waste (leachate) can occur during operation_jn4» would normally be considered an operational ra~tF«r than closure activity. Closure activities are those which _lejid_to_stabflTzation ~o~f~" the unit in a_ '.tinely Bannerafter receipt of wastes has ceased.. Four^b, '>the./characterist'i'cs and purpose of any"TlquldsTo be added^ Co the land'fill or to the cover during or after closure. must be specified in the closure or post-closure plans and approved by the RA (or authorized State), including any extension of the closure period. Such purpose and extension must be consistent with the environmental objectives specif-ted in Part 264 or 265. __ ~~~ Landfills that are currently engaged in co-disposal of hazardous and non-hazardous wastes could continue to accept non-hazardous wastes after January 25, 1983, in order to complete a partially filled hazardous waste unit and close under either 40. CFR Part 265 or Part 264 requirements. This assumes that the owner or operator completes the cell in a timely manner, which generally raeans within the 180 day closure period. I_f the closure cannot be completed _w_Lth-in the 180 days the owner or operator must apply to have the closure period extended beyond" 6 raonths, for a specified time period, as pr_oyide<1_ in *0 C?* 265". ir3.ibjL.9T 2S4. ttT(_b) *. to allow the waste to be filled until the designed elevation is reached. _ This type of closure could be approved if it - provides for a more enviroronentally sound closure, and not'"' 'merely for the economic convenience of the owner or operator. 'Each extension will be considered on a case—by-case basis. The regulatory concern is closing the landfill in as expedient a time as is practical (i.e., achieving final contour and final cover) so as to prevent additional rainfall infiltration and other environaental exposure.' Pertinent factors include use of earth materials and redesigning the final contours. The Regional Administrator or approved state permitting authority could approve a closure plan or modification to the closure plan allowing the unit or cell to be completed with non-hazardous waste after January 25, 1983, and possibly extending the closure period (wore than 6 months) after January 25, 1983 upon such a showing. Conditions foe accomplishing this would b« in any approved closure plan ------- or closura permit (e.g./ ti™* period, final contours, type of For the situation where a surface impoundment "closes as a landfill" before January 25 ,. 1983, I presume you mean no rnore hazardous wastes received after January 25, 1983, but cloaur® (e.g., dewatering, etc*) has not yet been done. The waste will be removed from the surface impoundment, solidified and replaced in the sane impoundment, to ensure that it will bear the weight of the cover. BPA do«a not consider this replacement of waste after January 25, 1983, to b« "recaipt" of hazardous waste which would constitute a "regulated unit". This decision assumes that the solidifying rxaterial is not a hazardous waste. For your last question you described the case where multiple hazardous waste trenches will cea^e to receive hazardous waste on or before January 25, 1983, -and where the closure plan provides for a delayed closure of a half- filled trench for the deposit of solidified hazardous waste from closed and capped trenches. - Tr ^""^ral , such placement trenches into tho reserved half ^-filled ttre-ac&r even at the same facility, will b« considered "receipt* of hazardous waste such AS to constitute a "regulated" unit.^&scause the waste is received and disposed at the facility unTE after January 26, 1983_. I refer you to the July 26, 1982 federal Register preamble discussion at 47 PP 32289 which describes the concept of a waste management unit. Where landfills consist of a series of trenches which are separately 'lined, each trench is a separate waste aanagement unit. The transfer of hazardous waste fron one unit to another after January 26, 1983 therefore makes the receiving trench or unit a "regulated* unit. _ As a side note, I should mention that the closure performance standard for interim status and for permitting facilities is the same (40 CFR 264.111 and 40 CP3 265.111). The final cover or cap for landfills closed under Part 264 or 265 standards should be siailar. - Significant Differences in the design of the cap should result from site specific factors rather than the type o? permit a facility ha«. Thus, many of the above comment 3 apply to both Part 264 and 265 closure requirements. I hope the above explanations help clarify the regulations for you. Should you have any further questions with regard to ------- how this regulation effects NSW*A members please contact r*e or Pred Lindsay of my staff (382-4756). Sincerely yours, John H. Skinner Acting Director Office of Solid Waste cc: Regions I - X (with incoming) Cook . Eileen Claussen. Joh n Lehna n Bruce We<1dle Lisa- Friedman Mark Greenwood Pred Lindaey Gene Lucero Ken Shuster ------- |