JP2016078006A - Final disposal site - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a final disposal site capable of coping with disposal of a mercury-containing waste matter.SOLUTION: A final disposal site 1 comprises: a landfill area 3 whose surrounding is defined by a side wall part 2; and a building 5 for storing the landfill area 3, and whose bottom part is formed of a bottom slab structure 4. The bottom slab structure 4 is formed of a first waterproof structure 30 and an RC layer 31 formed of plural reinforcement concrete layers 37 sequentially constructed from a lower layer side after respective cure period, and defining a bottom of the landfill area 3. The side wall part 2 is formed as an integrated article with the uppermost reinforcement concrete layer 37 of the RC layer 31, by the reinforcement concrete in which the reinforcement erected from the bottom part of the RC layer 31 serves as a main reinforcement 40, and a surface of the integrated article is coated with a second waterproof structure 46.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a final disposal site for landfill disposal of waste as a compacted body.

  In a disposal site for landfilling waste, it is necessary to take measures to prevent the leachate generated from the landfilled waste from leaking outside. As such measures, conventionally, a wall surface of a landfill section constructed of concrete is subjected to waterproofing using a water shielding sheet (for example, see Patent Document 1).

  In the construction method of the waste disposal site disclosed in Patent Document 1, a concrete placement form with a water shielding sheet attached to the wall surface of the concrete wall constituting the landfill section is blocked by the wall surface of the concrete wall. It is installed with the water sheets facing each other. Then, concrete is placed between the water shielding sheet of the mold and the concrete wall, and after curing for a predetermined period, the mold is removed. Thereafter, a resin material is sprayed on the exposed surface of the water shielding sheet.

JP 2003-236490 A

  By the way, mercury contained in mercury-containing waste such as used dry batteries and fluorescent lamps (hereinafter referred to as “mercury-containing waste”) has been conventionally collected and recycled as much as possible. However, in recent years, the demand for mercury has drastically decreased, and mercury-containing waste is often disposed of in landfills without being recycled.

  In this case, if leachate leaks from the mercury-containing waste to the outside of the disposal site, the environment surrounding the disposal site is greatly affected as compared to waste that does not contain mercury. Therefore, when landfilling mercury-containing wastes, several stricter measures against leakage are required than in the case of a disposal site constructed by the conventional method described above.

  An object of the present invention is to provide a final disposal site that can cope with landfill disposal of mercury-containing waste in view of the problems of the prior art.

  The final disposal site of the present invention includes a landfill area in which a plurality of landfill sections are set in which a fill material containing waste is input and a compacted body of the fill material is sequentially formed, and the periphery is defined by side walls. A building that houses the landfill area and has a bottom made of a bottom slab structure, wherein the bottom slab structure is provided on a first waterproof structure and on the first waterproof structure. The first waterproof structure is composed of concrete and a waterproof unit, and the RC layer is sequentially formed from the lower layer side through each curing period. It consists of a plurality of reinforced concrete layers to be constructed, and the side wall portion is made of reinforced concrete mainly composed of reinforcing bars raised from the bottom of the RC layer, and is integrated with the reinforced concrete layer on the top of the RC layer. Reinforced concrete Coat layer and is formed at the same time, the surface of the monolith is characterized by being covered with the second waterproof structure.

  According to the present invention, the bottom includes a building composed of a bottom slab structure, the bottom slab structure is composed of an RC layer composed of a plurality of reinforced concrete layers and a first waterproof structure, and the landfill area is an RC layer. And a side wall. And the side wall part is formed simultaneously as an integral part with the reinforced concrete layer on the top of the RC layer, with the reinforcing bar rising from the bottom part of the RC layer as the main reinforcement, and the surface of the integral part is covered with the second waterproof structure. .

  Therefore, the side wall portion, the second waterproof structure, and the building can reliably prevent the rainwater and the like from entering the landfill area. In addition, the first waterproof structure, the RC layer, and the second waterproof structure can effectively prevent leakage of leachate or the like from the compacted molded body containing waste in the landfill area into the ground. And a landfill area | region can be maintained firmly with a tough RC layer and a side wall part.

  For this reason, even when a change such as an earthquake occurs, it is possible to maintain the landfill region while reliably maintaining the waterproof / water-blocking effect by the first waterproof structure and the second waterproof structure. Therefore, the mercury-containing waste can be reliably landfilled without affecting the surrounding environment.

  In the present invention, each reinforced concrete layer of the RC layer is formed with induction joints provided with expansion joints on the upper surface, and the induction joints of each reinforced concrete layer are arranged at different positions in a direction parallel to the upper surface. May be.

  According to this, since the induction joint of each reinforced concrete layer has shifted | deviated, the crack induced by the induction joint can be disperse | distributed without concentrating on a specific location. As a result, it is possible to maintain the toughness of the RC layer by avoiding the occurrence of faults over the entire range in the thickness direction of the RC layer, regardless of the occurrence of cracks. In addition, the stretch joint material can effectively impart water barrier properties to the RC layer and maintain the water barrier properties regardless of the occurrence of cracks.

  In the present invention, the first waterproof structure includes a first concrete layer thrown into the ground, the waterproof unit provided on the first concrete layer, and a second concrete put on the waterproof unit. The waterproof unit may be composed of a waterproof sheet and a two-layer protective mat sandwiching the waterproof sheet from both sides.

  According to this, in combination with the effect of avoiding the occurrence of a fault over the entire range in the thickness direction of the RC layer formed on the first waterproof structure and the protective effect of the water shielding sheet by the protective mat, it is waterproof. The water barrier by the unit can be maintained at a high level.

  In the present invention, the second waterproof structure includes an innermost water-repellent layer, a waterproof layer formed by applying FRP waterproof processing to the outside of the water-repellent layer, and a non-combustible property that covers the waterproof layer. You may be comprised with a coat. According to this, the waterproof effect by the water repellent layer and the waterproof layer can be enjoyed while preventing a fire accident or the like by the nonflammable coat.

It is a perspective view of the final disposal site concerning one embodiment of the present invention. It is the II-II sectional view taken on the line of FIG. It is a perspective view which shows the induction joint of each reinforced concrete layer in RC layer of a final disposal site. It is a reinforcement arrangement | positioning which shows the reinforcement in the side wall part of RC layer of a baseboard structure, and a landfill area | region.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The final disposal site 1 of the embodiment can cope with safe landfill disposal of mercury-containing waste. As shown in FIG. 1, the final disposal site 1 is composed of two landfill areas 3 each surrounded by a side wall 2 and a bottom plate structure 4 (see FIG. 2). And a building 5 for housing.

  The shape of the building 5 as viewed from above has a rectangular shape. Each landfill area | region 3 has a rectangular shape where the shape along a horizontal surface is long along the length direction of the building 5, and it is arrange | positioned in parallel mutually.

  In each landfill region 3, a plurality of landfill sections 7 in which waste compacts 6 are sequentially formed are set. In FIG. 1, only one landfill section 7 is indicated by a one-dot chain line. A large number of such rectangular parallelepiped landfill sections 7 are defined in the landfill region 3 without gaps along the vertical, horizontal, and height directions of the landfill region 3.

  The compacted molded body 6 is formed by sequentially loading a filling material 8 obtained by kneading waste, cement, and the like into each landfill section 7, and compacting and hardening. In the building 5, a cement kneading chamber 9 for preparing the embankment material 8 by kneading waste and cement or the like is provided. A cement silo C for supplying cement for kneading is provided outside the building 5 in the vicinity of the cement kneading chamber 9.

  In the cement kneading chamber 9, a pit 10 for kneading, a heavy machine 11 on which a stirring bucket or the like can be mounted, a container 12 for transferring the embankment material 8, and the like are arranged. In the carry-in path of the transport vehicle 13 that leads to the cement kneading chamber 9, a first gate 14 and a second gate 15 constituted by airtight weight shutters are provided.

  Similarly, an airtight internal gate 17 is provided at the outlet to the transfer path 16 for transferring the embankment material 8 from the cement kneading chamber 9. As a result, the cement kneading chamber 9 can be kept airtight, and mercury components can be prevented from being scattered outside the cement kneading chamber 9 when the waste is kneaded.

  Outside the side wall 2 of the landfill area 3, a running path 19 is provided for running a ceiling hoist 18 that transports the embankment material 8 forming the compacted compact 6 to the landfill section 7 in the landfill area 3. The ceiling hoist 18 is caused to travel using the traveling path 19 and the hoist 20 (see FIG. 2) that is a winding mechanism portion of the ceiling hoist 18 is traversed, whereby the container 12 containing the embankment material 8 is compacted. It can be transported to the landfill section 7 where the body is to be formed.

  A relatively wide front space 21 is provided on the front side in the building 5. In the front space 21, a transfer path 16 and a forklift 23 for transferring the container 12 containing the embankment material 8 from the cement kneading chamber 9 to the delivery position 22 to the ceiling hoist 18 are arranged. The front side of the front space 21 is an entrance of the building 5 and is opened and closed by an airtight weight shutter 24.

  The building 5 is provided with a fire extinguishing equipment room 26 having a fire extinguishing equipment for sending an inert gas to a necessary place in the building 5 through a pipeline 25, and is provided in case of emergency. In addition, a management room 27 and a warehouse 28 are provided in the building 5.

  FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1 and shows a cross section of the bottom slab structure 4 and the like of the building 5. As shown in FIG. 2, the bottom slab structure 4 includes a first waterproof structure 30 provided on the ground 29 and an RC layer 31 provided on the first waterproof structure 30.

  The ground 29 is improved in advance by a ground improvement method such as a replacement method, a shallow layer mixing method, or a deep layer processing method according to the properties of the ground 29. The first waterproof structure 30 includes a first discarded concrete 32 as a first concrete layer placed on the ground 29, a waterproof unit 33 provided on the first discarded concrete 32, and a waterproof unit 33. It is comprised with the 2nd discarded concrete 34 as a 2nd concrete layer laid. The waterproof unit 33 includes a water shielding sheet 35 and a two-layer protective mat 36 that sandwiches the water shielding sheet 35 from both sides.

  The RC layer 31 is composed of three reinforced concrete layers 37. Each reinforced concrete layer 37 is constructed in order from the lower layer through a separate curing period. The curing period of each reinforced concrete layer 37 is, for example, 28 days.

  As shown in FIG. 3, each reinforced concrete layer 37 constituting the RC layer 31 is provided with an induction joint 38 on the upper surface. In FIG. 3, a second waterproof structure 46 (see FIG. 2) to be described later is not displayed so that the position of the induction joint 38 of each reinforced concrete layer 37 is easy to understand, and at a position along the appropriate induction joint 38. Each reinforced concrete layer 37 is shown cut.

  The induction joint 38 has, for example, a dimension of width 20 [mm] × depth 40 [mm]. The induction joint 38 is filled with an expandable joint material 39. The induction joints 38 of the reinforced concrete layers 37 are arranged at different positions in a direction parallel to the upper surface of the reinforced concrete layer 37. Specifically, the induction joints 38 of each reinforced concrete layer 37 are formed in a lattice shape at equal intervals in the vertical and horizontal directions, and the vertical or horizontal lines forming the lattice are parallel to the side wall 2. And the induction joint 38 of each reinforced concrete layer 37 has shifted | deviated 1/3 of the lattice space | interval mutually.

  For this reason, the cracks of each reinforced concrete layer 37 induced by the induction joint 38 are also shifted from each other by one third of the lattice spacing. Therefore, the part where the crack of one reinforced concrete layer 37 is overlapped with the part where the crack of the adjacent reinforced concrete layer 37 is not generated. For this reason, strength deterioration and flexibility reduction of the RC layer 31 due to induced cracks are kept to a minimum. Moreover, combined with the waterproof effect of the stretch joint material 39, the deterioration of the moisture barrier property of the RC layer 31 due to cracks is suppressed.

  As shown in FIG. 2 and FIG. 4, the side wall 2 defining the landfill region 3 is made of reinforced concrete having a reinforcing bar 40 as a main reinforcement 40 raised from the bottom of the RC layer 31, and the top reinforced concrete layer of the RC layer 31. The reinforced concrete layer 37 is formed simultaneously with the reinforced concrete layer 37. The bottom of the buried region 3 is defined by the RC layer 31.

  As shown in FIG. 4, the reinforcing bars of each reinforced concrete layer 37 constituting the RC layer 31 include reinforcing bars 41 arranged vertically and horizontally above the reinforced concrete layer 37, and reinforcing bars 42 arranged vertically and horizontally below the reinforced concrete layer 37. It consists of. And the part extended in the horizontal direction of the main reinforcement 40 raised from the upper part of the reinforcement 42 arrange | positioned in the grid | lattice form under the lowermost reinforced concrete layer 37 so that it may become perpendicular | vertical to the side wall part 2. Be placed.

  The side wall portion 2 includes a reinforcing bar group on the inner side (landing region 3 side) in which the main bars 40 and horizontal bars 43 extending in the horizontal direction along the side wall parts 2 are arranged in a lattice pattern, and similarly, the main bars 40 and the horizontal bars. 43 is formed as a reinforced concrete wall reinforced with a reinforcing bar group on the outside (opposite to the landfill region 3) arranged in a grid pattern. The main reinforcement 40 also has a function of fixing the reinforced concrete layers 37 to each other.

  As shown in FIG. 2, a vertical wall 44 raised from the uppermost reinforced concrete layer 37 of the RC layer 31 is provided at the periphery of the RC layer 31. The vertical wall 44 is formed by integrally solidifying the concrete introduced into the reinforced concrete layer 37 at the same time as an integral part with the uppermost reinforced concrete layer 37.

  On the outer side of the vertical wall 44, an extended portion 45 is formed in which only the uppermost reinforced concrete layer 37 of the RC layer 31 extends along the ground 29 surface by about 2 [m]. The extending portion 45 forms a step with respect to the portion of the RC layer 31 composed of the three reinforced concrete layers 37. The first waterproof structure 30 between the ground 29 and the RC layer 31 continues to the extending portion 45 through this step portion.

  The surface of the unitary body constituted by the RC layer 31, the side wall portion 2, and the vertical wall 44 is covered with the second waterproof structure 46 without a gap except for the outer surface of the vertical wall 44. The lower end surface of the side wall 57 of the building 5 is connected to the upper end surface of the vertical wall 44 via the second waterproof structure 46. The second waterproof structure 46 includes a water-repellent layer 47 formed by applying an inner water-repellent agent, a waterproof layer 48 obtained by subjecting the water-repellent layer 47 to FRP waterproof processing, and a waterproof layer 48. It is comprised with the outermost nonflammable coat 49 to coat | cover.

  A recessed area 50 opened upward by the vertical wall 44 around the building 5, the side wall 2 of each landfill area 3, and the RC layer 31 of the bottom slab structure 4 and covered with the second waterproof structure 46. It is formed. As shown in FIG. 1, the recessed area 50 is provided with a water collecting trough 51 for discharging rainwater or the like entering the recessed area 50.

  In FIG. 1, only a part of the side wall 57 and the roof 52 of the building 5 on the side opposite to the front side of the building 5 is shown. However, actually, the side wall 57 and the roof 52 of the building 5 are the bottom plate. The entire inside of the vertical wall 44 around the structure 4 is covered.

  In addition, although hidden in the building 5 in FIG. 1, a recessed region 50 is also formed between the side wall 2 and the vertical wall 44 on the opposite side of the front of the building 5 in each landfill region 3. In addition, a recessed region 50 is also formed between the opposing side wall portions 2 of each landfill region 3. The concave areas 50 on both sides of the building 5 displayed in FIG. 1, the concave areas 50 on the opposite side to the front surface, and the concave areas 50 between the landfill areas 3 are connected in a W shape. The traveling path 19 for the ceiling hoist 18 to travel is provided on the second waterproof structure 46 at the bottom of the recessed area 50.

  In this configuration, when landfilling the mercury-containing waste, first, cement or the like from the cement silo C is supplied to the mercury-containing waste carried by the transport vehicle 13 in the cement kneading chamber 9 in the building. The embankment material 8 is prepared by kneading these with a stirring bucket of the heavy machine 11. At the time of kneading, the first gate 14, the second gate 15 and the like are closed, and the cement kneading chamber 9 is maintained in a confidential state. Thereby, scattering of the mercury component to the outside at the time of kneading is avoided.

  The prepared embankment material 8 is put in a container 12, conveyed by a forklift 23 through an internal gate 17 and a transfer path 16 to a delivery position 22, and the compacted molded body 6 is formed from the delivery position 22 by a ceiling hoist 18. It is conveyed to the landfill section 7 to be formed. Until this transfer is completed, a dam 53 that closes the open side surface is disposed for the landfill section 7.

  The embankment material 8 conveyed to the landfill section 7 is put into the landfill section 7 from the container 12. In this way, the embankment material 8 that fills the landfill section 7 is placed with a pressure weight thereon, and is cured through a predetermined curing period to form a compacted body 6. In this way, compacted compacts are sequentially formed for each landfill section 7 in the landfill region 3.

  During this time, even when various weather fluctuations occur, the building 5, the vertical wall 44 around the building 5, the side wall 2 of the landfill region 3, and the RC layer 31 of the bottom slab structure 4, the RC layer 31, and the side wall 2 The second waterproof structure 46 provided on the vertical wall 44 prevents rainwater or the like from entering the landfill region 3. Further, by the second waterproof structure 46 and the waterproof unit 33 of the first waterproof structure 30 provided under the RC layer 31, leachate and the like from waste in the landfill area 3 is caused by the ground 29 and the building 5. Leakage outside is prevented.

  Even when a change such as an earthquake occurs, the RC layer 31 whose toughness and water-imperviousness are enhanced by each reinforced concrete layer 37 and its induced joint 38 and the main reinforcement 40 raised from the bottom of the RC layer 31 are strong. The landfill region 3 is firmly maintained by the side wall portion 2 having improved properties. Further, even when a crack occurs in the RC layer 31, the water shielding property of the RC layer 31 is effectively maintained by the induction joint 38 of the RC layer 31. Further, even when a change such as an earthquake occurs, the water shielding / waterproof effect by the first waterproof structure 30 and the second waterproof structure 46 is maintained without being impaired by the toughness of the RC layer 31 and the side wall 2. The

  Moreover, the embankment material is made by running the ceiling hoist 18 while enjoying the waterproof effect of the second waterproof structure 46 by the running path 19 provided on the second waterproof structure 46 in the recessed area 50 outside the landfill area 3. 8 transfers are performed. In addition, since the outer side of the second waterproof structure 46 is composed of the non-combustible coat 49, even if a fire accident or the like occurs, the waterproofing by the water repellent layer 47 and the waterproof layer 48 is not brought about. The effect is enjoyed.

  As described above, according to the present embodiment, the bottom 5 includes the building 5 including the bottom slab structure 4, and the bottom slab structure 4 includes the RC layer 31 including the plurality of reinforced concrete layers 37 and the first waterproof structure 30. The buried region 3 is defined by the RC layer 31 and the side wall 2. The side wall 2 is formed as an integral with the uppermost reinforced concrete layer 37 of the RC layer 31 with the reinforcing bar rising from the bottom of the RC layer 31 as the main reinforcement, and the surface of the integral is the second waterproof structure 46. Covered with.

  Therefore, the side wall 2, the second waterproof structure 46 and the building 5 can surely prevent rainwater or the like from entering the landfill area 3. Further, the second waterproof structure 46, the RC layer 31, and the first waterproof structure 30 effectively prevent leachate and the like from the compacted molded body 6 including waste in the landfill region 3 from leaking to the ground 29. Can be blocked. The landfill region 3 can be firmly maintained by the tough RC layer 31 and the side wall portion 2.

  For this reason, even when a change such as an earthquake occurs, the landfill region 3 can be maintained while reliably maintaining the waterproof / water-blocking effect by the second waterproof structure 46 and the waterproof unit 33. Therefore, the mercury-containing waste can be reliably landfilled without affecting the surrounding environment.

  Moreover, since the induction joint 38 of each reinforced concrete layer 37 has shifted | deviated, the crack induced by the induction joint 38 can be disperse | distributed without concentrating on a specific location. As a result, it is possible to maintain the toughness of the RC layer 31 by avoiding the occurrence of faults over the entire range of the RC layer 31 in the thickness direction, regardless of the occurrence of cracks. In addition, the stretch joint material 39 can effectively impart water shielding to the RC layer 31 and maintain the water shielding regardless of the occurrence of cracks.

  Further, the vertical wall 44, the side wall 2, and the RC layer 31 at the peripheral edge of the RC layer 31 form a recessed region 50 that is open upward and is covered with the second waterproof structure 46. Is provided with a water collecting trough 51 for collecting and discharging the water entering the water. Thereby, the recessed area 50 is caused to function as a buffer area for preventing rain water and the like from entering the landfill area 3 and leakage of moisture from the landfill area 3 to the outside of the building 5. It is possible to secure a higher level of blocking performance.

  In addition, since the traveling path 19 for traveling the ceiling hoist 18 is provided on the second waterproof structure 46 in the recessed area 50, the recessed area 50 functions as the above-described buffer area, and at the same time, the traveling path 19 is provided. It can also be used as an area for

  The first waterproof structure 30 includes a first discarded concrete 32 on the ground, a waterproof unit 33 thereon, and a second discarded concrete 34 placed thereon, and the waterproof unit 33 is shielded. It is composed of a water sheet 35 and a protective mat 36 sandwiching the water sheet 35. And on the 1st waterproofing structure 30, RC layer 31 in which generation | occurrence | production of the fault over the said thickness direction whole range was avoided is formed, and also the waterproof sheet 35 is protected by the protection mat 36, Therefore Waterproofing The water shielding by the unit 33 can be maintained at a high level.

  In addition, the second waterproof structure 46 includes the water-repellent layer 47, the waterproof layer 48 on the outer side, and the non-combustible coat 49 that covers the waterproof layer 48. The waterproof effect by the water repellent layer 47 and the waterproof layer 48 can be enjoyed while preventing the above.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, the present invention is preferable for waste other than mercury-containing waste, such as radioactive waste, as long as it is a waste that requires a high level of waterproofing / water-proofing and a strong landfill area, such as mercury-containing waste. Can be applied. Moreover, not only the final disposal of waste, but also radioactive waste can be used as an intermediate disposal site.

  DESCRIPTION OF SYMBOLS 1 ... Final disposal site, 2 ... Side wall part, 3 ... Landfill area, 4 ... Bottom plate structure, 5 ... Building, 6 ... Consolidation molded body, 7 ... Landfill section, 8 ... Filling material, 18 ... Ceiling hoist, 19 ... Running Road, 29 ... Ground, 30 ... First waterproof structure, 31 ... RC layer, 32 ... First discarded concrete (first concrete layer), 33 ... Waterproof unit, 34 ... Second discarded concrete (second concrete layer), 35 ... Water-proof sheet, 36 ... Protective mat, 37 ... Reinforced concrete layer, 38 ... Induction joint, 39 ... Elastic joint material, 40 ... Main reinforcement, 44 ... Vertical wall, 46 ... Second waterproof structure, 47 ... Water-repellent layer 48 ... Waterproof layer, 49 ... Non-combustible coat, 50 ... Concave area, 51 ... Catchment.

Claims (4)

A plurality of landfill sections in which a banking material containing waste is input and a compacted body of the banking material is sequentially formed, and a landfill region whose periphery is defined by a side wall portion;
Containing the landfill area, and comprising a building whose bottom is composed of a bottom plate structure,
The bottom plate structure is composed of a first waterproof structure provided on the ground and an RC layer provided on the first waterproof structure and defining the bottom of the landfill area,
The first waterproof structure is composed of concrete and a waterproof unit,
The RC layer is composed of a plurality of reinforced concrete layers sequentially constructed from the lower layer side through each curing period,
The side wall portion is formed simultaneously with the reinforced concrete layer as a unitary object with the reinforced concrete layer on the top of the RC layer, with reinforced concrete mainly composed of reinforcing bars raised from the bottom of the RC layer,
The final disposal site, wherein the surface of the integrated object is covered with a second waterproof structure.   In each reinforced concrete layer of the RC layer, induction joints having a stretch joint material are formed on the upper surface, and the induction joints of the reinforced concrete layers are arranged at different positions in a direction parallel to the upper surface. The final disposal site according to claim 1, characterized in that it is a final disposal site. The first waterproof structure is
The first concrete layer thrown into the ground,
The waterproof unit provided on the first concrete layer;
It is composed of a second concrete layer put on the waterproof unit,
3. The final disposal site according to claim 1, wherein the waterproof unit includes a waterproof sheet and a two-layer protective mat sandwiching the waterproof sheet from both sides.   The second waterproof structure includes an innermost water-repellent layer, a waterproof layer formed by applying FRP waterproofing to the outside of the water-repellent layer, and a nonflammable coat covering the waterproof layer. The final disposal site according to any one of claims 1 to 3, wherein the final disposal site is provided.