1、Standard Practice for Compost for Erosion/Sediment Control (Compost Blankets) AASHTO Designation: R 52-10 (2015)1American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1a R 52-1 AASHTO Standard Practice for Compost for Er
2、osion/Sediment Control (Compost Blankets) AASHTO Designation: R 52-10 (2015)1 1. SCOPE 1.1. This specification covers compost produced from various organic by-products for use as a surface mulch for erosion/sediment control on sloped areas. This technique may be used for both temporary and permanent
3、 erosion/sediment control applications. 1.2. This technique is appropriate for slopes up to a 2:1 grade (horizontal distance:vertical distance) and should only be used in areas that have sheet flow drainage patterns (not areas that receive concentrated flows). This technique may also be used on up t
4、o 1:1 slopes with proper consideration to length of slope and compost application rates (depth). 2. REFERENCED DOCUMENTS 2.1. ASTM Standard: D2977, Standard Practice for Particle Size Range of Peat Materials for Horticultural Purposes) 2.2. U.S. EPA Test Method: U.S. EPA, Test Methods for Evaluating
5、 Solid Waste, Physical/Chemical Methods, SW-846, 3rd Edition 2.3. TMECC Sampling and Test Method: Test Methods for the Examination of Composting and Compost (TMECC), jointly published by the USDA and USCC (2002, publishing as a part of the USDA National Resource Conservation Technical Bulletin Serie
6、s) 2.4. Other Standards: U.S. Composting Council Seal of Testing Assurance Program documents Development of Landscape Architecture Specifications for Compost Utilization, The U.S. Composting Council and the Clean Washington Center, 1997 3. GENERAL DESCRIPTION 3.1. Compost is the product resulting fr
7、om the controlled biological decomposition of organic material, occurring under aerobic conditions, which has been sanitized through the generation of heat and stabilized to the point that it is appropriate for its particular application. Active composting is typically characterized by a high-temper
8、ature phase that sanitizes the product and allows a high rate of decomposition, followed by a lower-temperature phase that allows the product to stabilize while still decomposing at a slower rate. Compost should possess no objectionable odors or 2015 by the American Association of State Highway and
9、Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a R 52-2 AASHTO substances toxic to plants and shall not resemble the raw material from which it was derived. Compost contains plant nutrients but is typically not characterized as a fertilizer. 3.2. Compo
10、st may be derived from a variety of feedstocks, including agricultural, forestry, food, or industrial residuals; biosolids (treated sewage sludge); leaf and yard trimmings; manure; tree wood; or source-separated or mixed solid waste. 3.3. Proper thermophilic composting, meeting the U.S. Environmenta
11、l Protection Agencys definition for a “process to further reduce pathogens” (PFRP), will effectively reduce populations of human and plant pathogens, as well as destroy noxious weed seeds and propagules. 3.4. Compost is typically characterized as a finely screened and stabilized product that is used
12、 as a soil amendment. However, most composts also contain a wood-based fraction (e.g., bark, ground brush and tree wood, wood chips, etc.) that is typically removed before use as a soil amendment. This coarser, woody fraction of compost plays an important role when compost is used in erosion and sed
13、iment control. It is even possible to add fresh, ground bark or composted, properly sized wood-based material to a compost product, as necessary, to improve its efficacy in this application. 3.5. Compost products acceptable for this application must meet the chemical, physical, and biological parame
14、ters outlined in Section 4. 4. CHEMICAL, PHYSICAL, AND BIOLOGICAL PARAMETERS 4.1. Compost products specified for use in this application are described in Table 1. The products parameters will vary based on whether vegetation will be established on the treated slope. 4.2. Only compost products that m
15、eet all applicable state and federal regulations pertaining to their production and distribution may be used in this application. Approved compost products must meet related state and federal chemical contaminant (e.g., heavy metals, pesticides, etc.) and pathogen limit standards pertaining to the f
16、eedstocks (source materials) in which they were derived. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a R 52-3 AASHTO Table 1Compost Blanket Parameters Parametersa,bReported as (Units of Measure)
17、Surface Mulch to Be Vegetated Surface Mulch to Be Left Unvegetated pHcpH units 5.08.5 N/A Soluble Salt Concentrationc(Electrical Conductivity) dS/m (mmhos/cm) Max 5 Max 5 Moisture Content %, wet weight basis 3060 3060 Organic Matter Content %, dry weight basis 2565 25100 Particle Size % passing a se
18、lected mesh size, dry weight basis 3 in. (75 mm), 100% passing 1 in. (25 mm), 90% to 100% passing 3/4in. (19 mm), 65% to 100% passing 1/4in. (6.4 mm), 0% to 75% passing Max particle length of 6 in. (152 mm) 3 in. (75 mm), 100% passing 1 in. (25 mm), 90% to 100% passing 3/4in. (19 mm), 65% to 100% pa
19、ssing 1/4in. (6.4 mm), 0% to 75% passing Max particle length of 6 in. (152 mm) Stability/MaturitydCarbon Dioxide Evolution Rate mg CO2-C per g OM per day 8 N/A Physical Contaminants (Man-made Inerts) %, dry weight basis 1 1 aRecommended test methodologies are provided in Test Methods for the Examina
20、tion of Composting and Compost (TMECC, The U.S. Composting Council). bLandscape architects and project (field) engineers may modify the allowable compost specification ranges based on specific field conditions and plant requirements. cEach specific plant species requires a specific pH range. Each pl
21、ant also has a salinity tolerance rating, and maximum tolerable quantities are known. When specifying the establishment of any plant or turf species, it is important to understand their pH and soluble salt requirements and how they relate to the compost in use. dStability/Maturity rating is an area
22、of compost science that is still evolving, and as such, other various test methods could be considered. Also, never base compost quality conclusions on the result of a single stability/maturity test. 4.3. Very coarse compost should be avoided if the slope is to be landscaped or seeded as it will mak
23、e planting and crop establishment more difficult. 4.4. In regions subject to higher rates of precipitation and/or rainfall intensity, higher compost application rates should be used. In these particular regions, as well as regions subject to wind erosion, coarser compost products are preferred. Note
24、 1Specifying the use of compost products that are certified by the U.S. Composting Councils Seal of Testing Assurance (STA) Program (postingcouncil.org) will allow for the acquisition of products that are analyzed on a routine basis, using the specified test methods. STA participants are also requir
25、ed to provide a standard product label to all customers, allowing easy comparison to other products. Where water quality is an issue, or in areas in proximity to sensitive water bodies, the appropriate compost product should be used and vegetating the compost blanket should be considered. 5. FIELD A
26、PPLICATIONS 5.1. The following steps shall be taken for the proper installation of compost as a soil blanket for erosion/sediment control on sloped areas. 5.1.1. Slightly roughen (scarify) slopes and remove large clods, rocks, stumps, roots larger than 2 in. in diameter, and debris on slopes where v
27、egetation is to be established. This soil preparation step may be eliminated where approved by the Project Engineer or Landscape Architect/Designer, or where seeding or planting is not planned. Where practical, track (compact) perpendicularly to contours on the slope using a bulldozer before applyin
28、g compost as a soil blanket. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a R 52-4 AASHTO 5.1.2. Apply compost at the rates specified in Table 2. Table 2Compost Blanket Application Rates Annual Ra
29、infall/Flow Rate Total Precipitation and Rainfall Erosivity Index Application Rate for Vegetated Compost Surface MulchaApplication Rate for Unvegetated Compost Surface Mulch Low 125 in., 2090 1/23/4in. (12.519 mm) 111/2in. (2537.5 mm) Average 2650 in., 91200 3/41 in. (1925 mm) 11/22 in. (37.550 mm)
30、High 51 in. and above, 201 and above 12 in. (2550 mm) 24 in. (50100 mm) aThese lower application rates should only be used in conjunction with seeding and for compost blankets applied during the prescribed planting season for the particular region. 5.1.2.1. Compost blanket application rates should b
31、e modified based on specific site (e.g., soil characteristics and existing vegetation) and climatic conditions as well as particular project-related requirements. The severity of slope grade, as well as slope length, will also influence compost application rates. 5.1.2.2. In regions subject to highe
32、r rates of precipitation and/or rainfall intensity, higher compost application rates should be used. In these regions, as well as those with spring snow melt and on sites possessing severe grades or long slope lengths, the compost blanket may be used in conjunction with a compost filter berm. The fi
33、lter berm may be 12 ft (30 cm60 cm) high by 24 ft (60 cm120 cm) wide, and may be placed at the top or base (or both) of the slope. In these particular regions, as well as regions subject to wind erosion, coarser compost products may be preferred. 5.1.2.3. In regions subject to lower rates of precipi
34、tation or rainfall intensity, or both, lower compost application rates may be used. Note 2Specific regions may receive higher rainfall rates, but this rainfall is received through low-intensity rainfall events (e.g., the Northwestern United States). These regions may use lower compost application ra
35、tes. 5.1.3. Compost shall be uniformly applied using an approved spreader unit, such as a bulldozer, side discharge manure spreader, etc. Alternatively, apply compost using a pneumatic (blower) unit, or other unit that propels the product directly at the soil surface, thereby preventing water from m
36、oving between the soil-compost interface. Thorough watering may be used to improve settling of the compost. Apply compost layer approximately 3 ft (90 cm) over the top of the slope, or overlap it into existing vegetation. 5.1.4. On highly unstable soils, use compost in conjunction with appropriate s
37、tructural measures. 5.1.5. Dry or hydraulic seeding may be completed following compost application, as required, or during the compost application itself, where a pneumatic unit is used to apply the compost. 6. TEST METHODS 6.1. The chemical, physical, and biological analysis of the compost shall be
38、 determined in accordance with the Test Methods for the Examination of Composting and Compost (TMECC), jointly published by the U.S. Department of Agriculture and the U.S. Composting Council (2002, publishing as a part of the USDA National Resource Conservation Technical Bulletin Series). (See Appen
39、dix X1.) 6.2. ASTM D2977 shall be used to determine compost gradation. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a R 52-5 AASHTO 7. SAMPLING, INSPECTION, PACKING, AND MARKING 7.1. The sampling,
40、 testing, packing, and marking of compost samples shall be done in accordance with TMECC 02.01-B (Selection of Sampling Locations for Windrows and Piles). 8. KEYWORDS 8.1. Compost; erosion control; sediment control; sheet flow; slope stabilization. APPENDIXES (Nonmandatory Information) X1. METHODS F
41、OR THE SAMPLING AND CHARACTERIZATION OF COMPOST X1.1. Sampling procedures to be used for purposes of this specification (and the Seal of Testing Assurance program) are as provided in 02.01, Field Sampling of Compost Materials, and 02.01-B, Selection of Sampling Locations for Windrows and Piles of th
42、e Test Methods for the Examination of Composting and Compost (TMECC), Chapter 2, Section One, Sample Collection and Laboratory Preparation, jointly published by the USDA and USCC (2002, publishing as a part of the USDA National Resource Conservation Technical Bulletin Series). The sample collection
43、section is available online at http:/compostingcouncil.org X1.2. Test Methods to be used for purposes of this specification are as provided in the Test Methods for the Examination of Composting and Compost (TMECC), jointly published by the USDA and USCC (2002, publishing as a part of the USDA Nation
44、al Resource Conservation Technical Bulletin Series). A list of such methods is provided in the table below and online at http:/compostingcouncil.org 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a
45、R 52-6 AASHTO Table X1.1Test Methods for Compost Characterization Compost Parameters Reported as Test Method Test Method Name pH pH units TMECC 04.11-A Electrometric pH Determinations for Compost. 1:5 Slurry Method. Soluble Salts dS/m (mmhos/cm) TMECC 04.10-A Electrical Conductivity for Compost. 1:5
46、 Slurry Method (Mass Basis). Primary Plant Nutrients: %, as-is (wet) and dry weight basis Nitrogen Total N TMECC 04.02-D Nitrogen. Total Nitrogen by Combustion. Phosphorus P2O5TMECC 04.03-A Phosphorus. Total Phosphorus. Potassium K2O TMECC 04.04-A Potassium. Total Potassium. Calcium Ca TMECC 04.04-C
47、a Secondary and Micro-Nutrient Content. Calcium. Magnesium Mg TMECC 04.04-Mg Secondary and Micro-Nutrient Content. Magnesium. Moisture Content %, wet weight basis TMECC 03.09-A Total Solids and Moisture at 70 5C. Organic Matter Content %, dry weight basis TMECC 05.07-A Matter Method. Loss on Ignitio
48、n Organic Matter Method. Particle Size Screen size passing through TMECC 02.12-B Laboratory Sample Preparation. Sample Sieving for Aggregate Size Classification. Stability (Respirometry) mg CO2-C per g TS per day mg CO2-C per g OM per day TMECC 05.08-B Respirometry. Carbon Dioxide Evolution Rate. Ma
49、turity (Bioassay) Percent Emergence Relative Seedling Vigor % (average) % (average) TMECC 05.05-A Biological Assays. Seedling Emergence and Relative Growth. X2. ADDITIONAL INFORMATIONWEBSITES X2.1. For additional information on regional precipitation rates or rainfall erosivity indexes go online at http:/www.ars.usda.gov/Research/docs.htm?docid=10621. X2.2. Find U.S. Composting Council Seal of Testing Assurance Program documents at http:/compostingcouncil.org/seal-of-testing-assurance. 1Formerly AASHTO Provisional Standard MP
