Road Noise Barriers as Longitudinal Waste Deposits – Lined Slopes With Geosynthetics Protecting the Environment

Kent P. von Maubeuge1, Phone: +49 5743 41-228, Mobile: +49 172 5297928, E-Mail: kvmaubeuge@naue.comAndy Post1, Phone: +49 941 29799141, Mobile: +49 172 5297976,E-Mail: apost@naue.comStephan Westhus1, Phone: +49 5743 41-239, Mobile: +49 172 5297940,E-Mail: swesthus@naue.com

1NAUE GmbH & Co. KG, Gewerbestr. 2, 32339 Espelkamp-Fiestel, Germany

KEYWORDS: noise barriers, contaminated sites, geosynthetic clay liners, geomembranes, environmental protection

ABSTRACT: Worldwide more and more road noise and view-blocking barriers are being built along roads, motorways and railway lines, with a core that is made from mineral waste. This waste material can be in the form of slag, ash from municipal waste incineration plants or contaminated soil from the rehabilitation of contaminated sites, residue from construction waste recycling or industrial processing residue (slag, ash, foundry sands, condi-tioned sludge etc.). These waste products have to meet certain environmental-chemical requirements and must be provided with a surface sealing for groundwater protection. This sealing system can be designed as a mineral sealing (compacted clay liner, CCL) or it can be made of geosynthetic material (geosynthetic clay liners GCL, geomembranes). The commonly required drainage layer can also be of gravel or crushed stone or it can comprise geosynthetic materials (geosynthetic drainage system). Many noise barriers have relative-ly steep slopes because there is limited space and the higher the barrier and the steeper the slope the greater the noise protection. The sealing and drainage systems therefore frequently require reinforcement in the form of geogrids to ensure slope stability.

1 REASONS AND LEGAL FRAMEWORK FOR WASTE RECYCLING IN GERMANY

The protection of natural resources is a major goal of a functioning close loop recycling management, and this is also stipulated in the Closed Substance Cycle Waste Management Act (KrW/AbfG) of 1994 for the Germany (amended to an act in 2012). Besides strategies for avoiding the occurrence of waste, the material recycling of waste material is also required as a substitute for the extraction of new raw materials from natu-ral resources and ranks second in the waste hierarchy. Many raw materials such as sand and gravel are not available in unlimited quantities, this already being due to the fact that there will be a shortage of excavation sites in densely populated areas in Germany. Re-use or recycling is therefore a key objective in a functioning circular economy and also essential in view of the huge quantities of mineral waste (approx. 200 million tons per year in Germany in 2011). If these vast quantities had to be disposed of, it would exceed the resources of existing landfills. In 2011 some 51 million tons of waste ended up in approx. 1,170 landfills in Germany (German Statistical Federal Bureau 2011).

On the other hand, there is the problem that recycled construction materials or industrial waste may contain harmful substances (environmental-chemical pollutants), these either coming from their production process, their use or through the mixing with other contaminated materials (e.g. during demolition work). Disposal in places other than landfill sites therefore also involves the risk of material with harmful contaminants being spread over large areas in, around or beneath civil engineering constructions.

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This has led to a conflict of aims or an area of tension between, on the one hand, the protection of resources through the recycling of used building materials and waste products from industrial production processes or from municipal waste incineration plants in the most sustainable manner possible – these then being spread over large areas in or beneath structures - and a reliable and safe disposal in central landfills. As the recy-cling of mineral waste is absolutely essential for the above given reasons, it is therefore necessary to impose conditions such as compliance with threshold values, placement restrictions and technical protection measures. A recycling of waste that does not cause harm to man or the environment, especially surface water and groundwater, is required in both the German Closed Substance Cycle Waste Management Act (KrWG 2012) and in the German Federal Soil Protection Act / Soil Protection Ordinance (BBodSchG 1998, BBodSchV 1999), as in the Federal Water Resources Act (WHG 2009), as well as in Groundwater Requirements (GrwV 2010). In the construction industry the recycling of construction debris and its reuse as recycling material has been an established procedure for many years. Many other industrial sectors also produce industrial waste in their production processes (slag, ash, foundry sands, tailings) that can be recycled and used as construction ma-terials (waste for recycling). Recycled construction materials can be used as a substitute for natural products (sand, gravel, crushed stone, stones), also concrete aggregates such as cement clinker can be replaced by foundry sands from blast furnace slag, fly ash and silica fume, and asphalt aggregates such as crushed stones and bitumen can be replaced by reclaimed road construction waste and milled asphalt. These materials are therefore consid-ered as substitute construction material. Other residual materials that occur in large quantities are slags from metal smelting, municipal waste incineration slags, foundry sands and tailings from gravel washing plants. These can be used as a full, or in most cases at least as a partial substitute for natural raw materials (substi-tute construction material). In 1994, the LAGA (federal state working group for waste) published the Guideline M20 on “Requirements for the material recycling of mineral residues/wastes – Technical Regulations“, that was implemented in most of the German Federal States by decree in its revised form of November 6, 1997, and later as Technical Regulations on Soil in the current version of 05.11.2004 (LAGA TR Boden 2004). The LAGA Guideline M20 currently still governs the recycling of mineral waste in the Federal Republic of Germany, even though some Federal States have drawn up their own codes of practice, these, however, being basically in line with the LAGA Guideline. The preferential reuse is for road or also railroad embankments and in noise and sight barriers, without or with the defined technical protection measures, depending on the contamination class. Technical protection measures are water impermeable surface layers of asphalt or concrete (road surface) for road embankments and mineral sealing systems (CCL), synthetic liners (geomembranes) and geosynthetic clay liners (GCL) for road slopes and noise barriers. The Federal Ministry for the Environment, Nature Conservation and Nuclear Safety has taken on the job of issuing a German regulation in the form of the Combined Ordinance (2nd Revision of MantelV), including the Substitution Construction Material Ordinance (ErsatzbaustoffV 2010), a change of the Ground Water Ordi-nance (GwrV), a change in the German Federal Soil Protection Act (BBodSchG) and a change in the Landfill Directive (DepV). In this Combined Ordinance (MantelV 2012) it should be regulated what conditions are recommended for the use of recycled construction waste material in technical structures as well as use of soil substitute material, which are not considered as waste. The current version of the construction tables from the Substitution Con-struction Material Ordinance (ErsatzbaustoffV 2010), appendix 2, Table 1, also includes construction meth-ods from M TS E (2009).

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2 PROTECTING THE ENVIRONMENT DURING THE RECYCLING OF RESIDUES AND WASTE In Germany, as in other European countries like the Netherlands, protecting the environment during the re-cycling of waste is carried out using three barriers, similar to the disposal of waste in landfills:

1. Hydraulic conductivity of the subsoil, depth to groundwater table, groundwater-protecting cover layers 2. Limitation of pollutant load through assigned threshold values 3. Technical protection measures using water impermeable cover and sealing layers

The LAGA Guideline M20 (1994/97) and TR Boden (2004) as well as other comparable codes of practice control the recycling of “Z materials. For the disposal of polluted soil according to LAGA TR Boden (2004) additional requirements for the subsoil, the depth to groundwater table and the groundwater-protecting cover layers in consideration to Figure 1 are defined as follows:

• Z0 material (classification group)

=> uncontaminated soil => open placement possible anywhere

• Z1.1 material (classification group) => slightly contaminated waste, e.g. crushed concrete and bricks etc.

• Z1.2 material (classification group) => waste with slightly higher contamination, e.g. construction waste, slag, foundry sands etc. => open placement only possible in hydrogeological favourable areas, i.e. with a 2 m cohesive cover layer protecting the ground water

• Z2 material (classification group) => highest contamination class for recycling outside of landfills, e.g. polluted construction waste, slag, ash, foundry sands etc. => placement only using technical protection measures (surface sealing system made of water imper-meable cover layers of concrete or asphalt pavement, compacted clay liners, geomembranes, geosyn-thetic clay liners)

Figure 1: Construction Classification of soils with Acceptance Values

According to the LAGA TR Boden (1994) and the VWV Bodenverwertung (2007) the barrier capping system should be equivalent to a 0.5m thick clay liner with a hydraulic conductivity k of k ≤ 1 x 10-9 m/s, similar to the requirements of the Landfill Directive (DepV 2009). The hydraulic conductivity of a geosynthetic clay liner is regulated in the VWV Bodenverwertung (2007) with k ≤ 5 x 10-11 m/s. The thickness d and the quality of the recultivation layer was recommended with d ≥ 1m in the LAGA TR Boden 2004 and with a frost-resistant and desiccation-safe design for the sealing.

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3 STATE-OF-THE-ART CONSTRUCTION METHODS Experiences gathered mostly from landfill capping systems during the nineties and at the beginning of this century in test fields and excavations, especially concerning the desiccation behavior of weather-sensitive sealing systems (mostly mineral sealing systems, but also geosynthetic clay liners), were implemented with different structures in 2009 in the Guidelines on construction methods for protection measures in earthworks when using soils and construction materials that contain environmentally relevant substances (M TS E).

In doing so, a distinction has been made for the first time between sealing elements that are resistant to weather conditions (mostly synthetic liners d ≥ 2 mm) and weather-sensitive sealing elements (compacted clay liners, geosynthetic clay liners), giving different requirements regarding the thickness of the recultivation layer. Also the optional use of drainage layers above the sealing layer and the resulting difference in the permeability coefficient requirements reflect the experiences gathered from the construction of landfill sur-face sealing systems. The construction methods A, B (Figure 2) and C (Figure 3) are particularly important for the placement of geosynthetic materials.

Figure 2: • Method A: Weather sensitive barrier without drainage / Method B: Weather sensitive barrier

with drainage

Figure 3: • Method C: Dam Construction (Barrier system not weather sensitive)

The most significant changes compared to earlier guidelines, e.g. LAGA M20 (1994/97 and also the Tech-nical Instructions on Soils (LAGA TR Boden 2004) are the substantially increased thicknesses of the reculti-vation layer (cover soil d ≥ 1.5 m) above the sealing system in weather sensitive systems. The requirements regarding the permeability of mineral sealing systems with k ≤ 5 x 10-9 m/s are derived from the Technical Instructions on Municipal Waste (TA Siedlungsabfall 1993) and the Landfill Directive (DepV 2009). While a geomembrane can be considered as impermeable, if installed properly, mineral sealing systems, e.g. clay liners and GCLs, are measured based on their permittivity. To be able to compare different thick-nesses of mineral sealing systems with each other, the hydraulic conductivity k is calculated to a thickness d independent permittivity value ψ.

Sealing system equivalent to d ≥ 0,5 m k ≤ 1.10-10 m/s

Sealing system equivalent to d ≥ 0,5 m k ≤ 1.10-9 m/s drainage required

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ψ = k/d [1/s] (1)

Based on the experience that without the use of a drainage layer a higher accumulation is to be expected at the border between sealing layer and cultivation layer, and a higher hydraulic gradient (i) also causing in-creased seepage, the lower permeability value k ≤ 5 x 10-10 m/s is derived for this solution (without drainage) instead of k ≤ 5 x 10-9 m/s (with drainage layer). A drainage layer is also advantageous in regard to stability, as accumulating seeping water together with pore water and flow pressures always have a detrimental im-pact on the stability. Table 1 allows an overview of the essential requirements of the barrier systems with Geosynthetics (method A, B, C as shown by sketches), especially focused on the GCL in the M TS E and RiStWag recommenda-tions for environmental protection applications.

Table 1: Compilation of requirements given by RiStWag and MTSE, Germany

Requirement according to regulation

GM: Thick-ness

GCL: Permittivity

Cover soil [m]

Remarks

[mm] [1/s]

RiStWag

2.0 - 0.6

For chemical durability the DIBt certification ap-plies; protection layer 0.1 m sand or nonwoven geotex-tiles according to BAM regulation

- ψ ≤ 1 ⋅ 10-7 0.8 Frost/thaw and dry/wet testing required; re-sistance against hydrocarbons and salty condi-tions(1)

MTSE A - ψ ≤ 1 ⋅ 10-9 1.5

Permeability of cover soil must be 1000 times larger than the permeability of the sealing system; multi-component GCL with polymer coating

MTSE B (2)

(I) - ψ ≤ 1 ⋅ 10-8 1.5 Verification of internal shear resistance; products according to TL GeoK E-StB - 1,5 m cover soil - GCL - 0.8 m cover soil multi-component GCL with pol-ymer coating as desiccation and root barrier

(II) - ψ ≤ 2.5 ⋅ 10-

12 0.8 (3)

MTSE C

(I) 2.0 - ≥ 0.1 (4)

GM (HDPE) with DIBt certification, ≥ 2.0 mm; overlaps welded; installation plan; certified in-staller; protection layer 0.1 m sand or nonwoven geotex-tiles (≥ 300 g/m², d ≥ 2.5 mm and GRK 5

(II) 2.0 ψ ≤ 1 ⋅ 10-9 0.8 (3) Multi-component GCL with polymer coating as desiccation and root barrier

MTSE E (II) 2.0 - ≥ 0.1

Base liner with geosynthetic drainage system as leak detection system

(1) ψ ≤ 5 ⋅ 10-9 1/s (data sheet) with performance certification (2) as A, with mineral drainage system or geosynthetic drainage system (3) reduced cover soil thickness with multi-component GCL with polymer coating as desiccation barrier (4) requirements according to vegetation and erosion control

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When constructing traffic routes it is possible, on the one hand, to use encountered contaminated soil and also non-contaminated and contaminated soils from other excavation sites in embankments as well as noise and visual barriers. Besides contaminated soil, in Germany it is also possible to use other mineral waste and industrial waste (e.g. ash and slags from municipal waste incineration, recycled construction debris or RC material, foundry sands, tailings etc.) up to the placement class Z2. In the Netherlands slags from municipal waste incineration (MVA-S, or Dutch: AVI Bodemas) are used as construction material in noise barriers and dams. These contaminated materials must receive effective protection against the entry of precipitation through technical protection measures (sealing systems), these also preventing respective emissions into the underlying subsoil and groundwater. The Guideline M TS E (2009) of the German Road and Transportation Research Association provides the road construction engineer with a reference from which he can select appropriate sealing methods and their framework conditions.

4 ADVANTAGES OF COATED MULTICOMPONENT GCLS The success of needle punched GCLs has been proven in approximately 100 million square meters of in-stalled material since 1987 and recently, since the introduction of the M TS E Guideline in various projects. However, to improve the internal shear strength of needlepunched GCLs to achieve ever-better ecological, economical and performance-related benefits for engineers, further innovations have also been pursued with the outer layers of the GCL. The polymer coating option of a new generation of multicomponent GCLs (Fig-ure 4) is helping make GCL installations even more effective, safer and longer lasting. With its additional multi-component barrier layer, this polymer-coated GCL offer economical, long-term barrier solutions that are ideal for a wide range of sealing applications. Each variety is designed to meet specific barrier situations, such as managing hydraulic heads, reducing the risks associated with chemical environments, guarding against root penetration, and accounting for desiccation. It now allows a GCL to be used in method A, B and C without limitation as it meets all M TS E requirements for these applications.

Figure 4: • Structured polymer coating added to needle-punched GCL during the manufacturing process

Advantages in utilising this polymer coating include the following topics in M TS E applications but are not limited to those.

• Prevention of Root Penetration: As plant and tree roots search for water, they spread in all directions horizontally and vertically, and will continue this search until they find enough water to sustain the plant. This search can impact a GCL installation. As described earlier, bentonite hydrates once in contact with fresh water, including moisture from the surrounding soil. Due to the bentonite's out-standing sorption capacity, the bentonite will typically have higher moisture content than the sur-rounding soil. Roots can be attracted to this moisture. Though high-quality powdered sodium benton-ite possesses self-sealing properties, root penetration should not be encouraged. Roots can extract water content from bentonite. Placing the coated slit-film woven geotextile side against the direction of potential root growth will protect the hydrated bentonite core from root penetration - thus, main-taining a high bentonite moisture content and a high level of design safety and sealing performance.

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• Increasing Resistance against Desiccation: According to soil mechanics, swellable and hydrated soils shrink when desiccating. In clays, this is typically revealed with cracking. The same mechanics can affect swellable bentonites. Such desiccation can occur in arid and semi-arid areas, in regions with low soil coverage or little rainfall, and in applications where the bentonite does not have con-stant access to fresh water. Even though needle-punched, fibre-reinforced GCLs will show a much smaller crack pattern than unreinforced or poorly reinforced GCLs, a desiccation crack pattern will increase fluid or gas permeation rates prior to the self-sealing of the bentonite (which occurs upon contact with fresh water). If this is not acceptable for the designed application, the polymer-coated GCL can be used with the polymer coating facing the direction of expected desiccation. In most cas-es, this will be the upper side of the GCL. The upside-facing polymer coating of the GCL would pre-vent moisture escape and allow the bentonite to be hydrated and act as a barrier, even in arid areas or under very low confining stresses, such as in tank farm applications.

• Lower Permeability: Needle-punched GCLs have a strong history as a stand-alone barrier, largely due to the high grade of powered sodium bentonite used in the GCL’s construction. This sodium bentonite exhibits high swelling behavior, low water permeability, excellent water absorption and re-tention capacity, and a unique self-sealing/-healing effect. These exceptional capabilities of the ben-tonite remain, even with the use of a polymer coating on GCL. This extra coating simply adds its ad-vantages to the GCL which increases the GCL performance. The coating improves overall performance while further lowering the hydraulic conductivity of the GCL. With these advantages now combined, needle-punched GCLs outperform nearly any sealing system in regard to hydraulic conductivity during the service life of the coating and beyond.

• Barrier against Ion Exchange: When a GCL is in contact with fluids and soils containing leachable

cations, such as calcium (Ca), magnesium (Mg), potassium (K) or other polyvalent cations, an ion exchange of the sodium (Na) portion of the GCL can occur. If it does, the clay structure of the GCL core can be affected, which might impact the swelling capacity and the hydraulic conductivity per-formance. However, it is impossible to make general statements on the long-term performance of a GCL under these conditions. Using calcium bentonite instead as the sealing core in a GCL, even with a higher mass per unit area (e.g. 8 to 10kg), is not a suitable option. Published results (Henken-Mellies, 2010; Mueller-Kirchenbauer, 2010) have shown that the hydraulic conductivity results of field exposed calcium bentonite are far higher than ion exchanged sodium bentonite GCLs. In applica-tions where this issue might be a concern, a polymer coating on the GCL facing the possible polyva-lent cation source can help guard against this possible ion exchange. In most applications water, which is the hydration source for the bentonite, comes from the top and permeates through the soil layer above the GCL. In applications with soils that have a high concentration of free available leachable cations, a coated GCL is an ideal solution. The thin coating facing the source of ex-changeable cations acts as a barrier and protects the sodium bentonite sealing core of the GCL.

• Gas Barrier: In applications in which the GCL has to perform immediately as a gas barrier, the po-rous bentonite core might not have time to fully hydrate with water and fulfill its sealing performance due to immediate gas migration. Applications of this nature include the waterproofing of underground structures, landfill caps, and other applications in which the GCL is installed over an active source of gas production. The coated barrier of needle-punched GCL would act as the gas-impermeable barri-er, thus allowing the installation and welding of a geomembrane. In applications where no additional barrier is installed in combination with the GCL, such as with underground waterproofing systems, the polymer coating will take over the immediate sealing performance against possible penetrating gas. In both cases the sealing of the coated overlaps of the GCL can easily be carried out with a special bituminous tape.

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5 DESIGNING WITH POLYMER COATED GCLS For designing with polymer coated GCLs, additional design issues may need to be considered. These can include but are not limited to one or more of the following topics:

• Durability of the Coating: In most cases the GCL coating is expected to have a long service life. For this reason, the polymer coating should be manufactured with a highly chemically resistant polyeth-ylene resin.

• Resistance against Installation Stress: It is important to know the resistance of the additional barrier against installation stresses.

• Overlapping of Polymer Coated GCLs: Geosynthetic clay liners are overlapped during installation.

To provide security against permeation, additional powdered bentonite is sometimes applied to the overlap zones on site. On site treatment, however, is not as dependable (in that it is not as uniform) as providing the additional bentonite at the edges during the manufacturing stage, e.g. some GCL panels are impregnated during manufacturing on both longitudinal edges with 500mm of additional bentonite. This impregnation ensures that these overlapped, bentonite-treated areas act immediately as a seal without any need for on-site bentonite treatment. In applications where GCLs needs to act immediately as a gas or chemical liquid barrier, or in applications where bentonite piping in the over-lap zone may be of concern, a special tape (made with a strong adhesive bitumen) is recommended to seal the overlap on the coating side.

• Transmissivity between Coating and GCL: Due to the unique manufacturing process, the polymer

coating is added in a fluid state directly on top of the woven component of the GCL. This allows the polymer coating to penetrate into the woven structure, surround the needlepunched fibres from the nonwoven outer geotextile and attach firmly, uniformly and directionally-independent to the entire woven GCL component. In the unlikely event of damage to the coated barrier, penetrating water that could flow under the coated woven component would cause the sodium bentonite layer to immedi-ately swell and form a seal against the damage. This self-sealing characteristic of the GCL prevents a large radial displacement of penetrating water; and it’s a characteristic unique to GCLs in barrier system designs.

• Interface Shear: For slope designs, the critical friction plane needs to be investigated with the site

materials and is typically confirmed with multiple shear box tests. This is true of nearly all materials considered in slope applications, such as soil, GCLs, other geosynthetics used on slopes, etc. For steeper slopes, the use of geogrid soil reinforcement can significantly improve the slope friction an-gle.

• Peel Value of Coating: Because GCLs are composite materials and the single layers are designed to

work together, the peel bond strength between the GCL components is of particular interest. The needlepunched construction of a specific GCL increases the internal shear strength, ensuring a firm lock between the single GCL outer layers and the powdered sodium bentonite core (Ehrenberg and von Maubeuge, 2008). The same bond holds true when adding the polymer coating as an additional barrier. Even though the interface friction value of the coated material to surfacing materials might be the dominating value, it is important that all possible surfaces and layers are properly investigated to avoid shearing of any type. Special shear testing between the component carrier woven layer and at-tached polyolefin coating demonstrates a very good peel bond strength, which indicates that this connection face is, under most conditions, not the critical friction surface.

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6 SUMMARY Due to the huge amounts of mineral waste produced and the shortage of natural building material resources (e.g. sand, gravel, crushed stone) it is a primary task to recycle this mineral waste material according to the Closed Substance Cycle Waste Management Act (KrW/AbfG 1994). Based on their production process, their re-use or the mixing with contaminated construction materials during demolition work, these mineral wastes often contain substances that have a harmful impact on the environment. It is therefore necessary, when re-cycling these materials in traffic route embankments and noise or vision barriers, to apply protection measures (sealing systems) that prevent the entry of precipitation and the leaching of harmful substances in-to the groundwater. There are a number of suitable sealing materials available for this purpose, including geosynthetic clay liners and geomembranes. When designing these liners the following must be taken into account:

• permeability coefficient requirements:

For mineral sealing systems (CCL) without drainage layer very strict requirements concerning permittivity of the CCL and the permeability of the cover layers are formulated, compare chapter 3, Table 1, Method A. To be more efficient a system with CCL or GCL with drainage layer can be used, compare chapter 3, Table 1, Method B.

• weather sensitiveness of mineral sealing elements: − For CCL and GCL substantially thicker recultivation layers (d ≥ 1.5 m) are required. − For this application, geomembranes or multi-component GCLs (with polymer coating, thickness ap-

prox. 0.2 mm to 1 mm, structured) can be proven to be suitable for this application. − Thinner cover soil layers might be possible with site-specific plant requirements.

Both guidelines, the Dutch guidelines on the construction material ordinance „Bouwstoffen Besluit“ (CUR 1999) and the German guidelines M TS E of the FGSV (2009), provide technical information on the possible design of such protection measures and sealing components in order to meet the high stability requirements (> 100 years). Multi-component GCLs allow safer and economic designs in method A, B and C of the M TS E guideline and act as a double-lined system with very low permeability values.

7 REFERENCES AND FURTHER READING ON THE SUBJECT BBodSchG - Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit (1998): Gesetz zum Schutz

vor schädlichen Bodenveränderungen und zur Sanierung von Altlasten (Bundes-Bodenschutzgesetz - BBodSchG) (BGBl. I S. 502), Bonn.

BBodSchV - Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit (1999): Bundesbodenschutz

und Altlastenverordnung (BBodSchV) (BGBL I S. 2585), Bonn. CUR - Civieltechnisch Centrum Uitvoering Research en Regelgeving (1999): Aan het werk met het

„Bouwstoffen Besluit“ Een handreiking voor het werken met het Boustoffenbesluit. Ministerie van Volkshuisvesting Ruimtelijke Ordening en Miliuebeheer. C·R·O·W kenniscentrum voor verkeer vervoer en infrastructuur, Sdu Uitgevers, NL.

DepV - Ministerium für Umwelt, Naturschutz und Reaktorsicherheit (2009): Verordnung zur Vereinfachung

des Deponierechts vom 27. April 2009, Artikel 1 Verordnung über Deponien und Langzeitlager (Deponieverordnung – DepV). Bundesgesetzblatt Jg. 2009, Teil I Nr. 22. Bundesanzeigerverlag, Köln.

EHRENBERG H., von MAUBEUGE K. P., 2008, "Long-term Shear Strength Testing with Geosynthetic Clay

Liners and Geosynthetic Drainage Mats", The First Pan American Geosynthetics Conference & Exhibi-tion, Cancun, Mexico

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GrwV Grundwasserverordnung – Ministerium für Umwelt, Naturschutz und Re-aktorsicherheit (2010):

Verordnung zum Schutz des Grundwassers (Grundwas-serverordnung – GrwV). HENKEN-MELLIES W.-U., 2010; "GCL in a landfill final cover: 10-year record of a lysimeter field test", 3rd

International Symposium on Geosynthetic Clay Liners Würzburg, Germany KrWG - Ministerium für Umwelt, Naturschutz und Reaktorsicherheit (2012): Ge-setz zur Förderung der

Kreislaufwirtschaft und Sicherung der umweltverträgli-chen Bewirtschaftung von Abfällen (Kreislaufwirtschaftsgesetz – KrWG) vom 24.02.2012. www.gesetze-im-internet.de/¬bundesrecht/krwg/gesamt.pdf.

LAGA Ad-hoc-AG „Deponietechnik“ (2012): Bundeseinheitlicher Qualitätsstandard 5-5

Oberflächenabdichtungskomponenten aus geosynthetischen Tondichtungsbahnen vom 02.08.2012 http://www.laga-online.de/servlet/is/26509/BQS_5-5_Geosynthetische_Tondichtungsbahnen_12-08-02.pdf

LAGA Länderarbeitsgemeinschaft Abfall Ad-hoc-AG „Deponietechnik“ (2012):

Oberflächenabdichtungskomponenten aus Geosynthetischen Tondichtungsbahnen http://www.laga-online.de/.

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stoffliche Verwertung von mineralischen Reststoffen und Abfällen. LAGA TR Boden- Mitteilungen der Länderarbeitsgemeinschaft Abfall (LAGA) (2004): Anforderungen an die

stoffliche Verwertung von mineralischen Reststoffen und Abfällen: Teil II: Technische Regeln für die Verwertung. 1.2 Bodenmaterial (TR Boden), Stand 05.11.2004.

MantelV - Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit (2012): Verordnung zur

Festlegung von Anforderungen für das Einbringen oder das Einleiten von Stoffen in das Grundwasser, an den Einbau von Ersatzstoffen und für die Verwendung von Boden und bodenähnlichem Material. „Mantelverordnung“. Art. 1 Änd. GrwV, Art. 2 ErsatzbaustV, Art. 3 Änd. DepV, Art. 4 Änd. BBodSchV. Entwurf vom 31.10.2012. http://www.bmu.de/

M Geok E - Merkblatt für die Anwendung von Geokunststoffen im Erdbau des Straßenbaus, Ausgabe 2005.

FGSV-Nr. 535, Köln. M TS E - Forschungsgesellschaft für das Straßen- und Verkehrswesen (FGSV) (2009): Merkblatt über

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