1.DESCRIPTION Furnish and place compost as shown on the plans.
2.MATERIALS Furnish compost that has been produced by aerobic (biological) decomposition of organic matter and meets the requirements shown in Table 1. Compost feedstock may include, but is not limited to, leaves and yard trimmings, biosolids, food scraps, food- proces sing residuals, manure or other agricultural residuals, forest residues, bark, and paper. Ensure compost and wood chips do not contain any visible refuse, other physical contaminants, or any substance considered harmful to plant growth. Do not use materials that have been treated with chemical preservatives as a compost feedstock or as wood chips. Do not use mixed municipal solid waste compost. Provide compost in accordance with 40 CFR 503 for Class A biosolids and TCEQ health and safety regulations as defined in the TAC, Chapter 332, including the time and temperature standards in Subchapter B, Part 23. Meet the requirements of the United States Composting Council (USCC) Seal of Testing Assurance (STA) program. Before delivery of the compost, provide quality control documentation that includes the following: the feedstock by percentage in the final compost product, a statement that the compost meets federal and state health and safety regulations, a statement that the composting process has met time and temperature requirements, a copy of the producer’s STA certification, and a copy of the lab analysis, performed by an STA -certified lab, verifying that the compost meets the requirements shown in Table 1. Provide a copy of the current TCEQ compliance statement signed by the facility manager when furnishing biosolids compost. Table 1 Physical Requirements for Compost Property Test Method Requirement Particle Size TMECC1 02.02 -B, “Sample Sieving for Aggregate Size Classification” 95% passing 5/8 ” 70% passing 3/8 ” Heavy Metals Content TMECC 04.06, “Heavy Metals and Hazardous Elements”:
04.06 As, Arsenic
04.06 Cd, Cadmium
04.06 Cu, Copper
04.06 Pb, Lead
04.06 Hg, Mercury
04.06 Mo, Molybdenum
04.06 Ni, Nickel
04.06 Se, Selenium
04.06 Zn, Zinc Pass
Salinity TMECC 04.10 -A, “1:5 Slurry Method, Mass Basis” 5.0 dS/m Max2 pH TMECC 04.11 -A, “1:5 Slurry pH” 5.5–8.5 Maturity TMECC 05.05 -A, “% Emergence and Relative Seedli ng Vigor” >80% Organic Matter Content TMECC 05.07 -A, “Loss -On-Ignition Organic Matter Method” 25–65% (dry mass) Stability TMECC 05.08 -B, “Carbon Dioxide Evolution Rate” ≤8 Fecal Coliform TMECC 07.01 -B, “Fecal Coliforms” 1,000 MPN/g Max
1.Test Methods for the Examination of Composting and Compost, published by the United States Department of Agriculture and USCC.
2.A soluble salt content up to 10.0 dS/m for compost used in compost -manufactured topsoil will be acceptable. 125 Maintain compost in designated stockpiles at the producer’s site. The Department reserves the right to sample compost at the jobsite. Material may be tested to verify compliance with this Specification by an STA- certified laboratory . Make payment to the STA -certified laboratory approved by the Department. Submit laboratory invoices for passing tests to the Department for reimbursement. Maintain a complete record of all test reports for the previous and current calendar year s. 2.1. Compost Manufactured Topsoil (CMT) . Use CMT consisting of 75% topsoil blended with 25% compost measured by volume. Use topsoil in accordance with Article 160.2., “Materials.” 2.2. Erosion Control Compost (ECC) . Use ECC consisting of 50% untreated wood chips blended with 50% compost measured by volume. Use wood chips less than or equal to 5 in. in length with 95% passing a 2- in. screen and less than 30% passing a 1- in. screen. 2.3. General Use Compost (GUC) . Use GUC consisting of 100% compost.
3.CONSTRUCTION Prepare the types of compost for use on the project , and stockpile at the jobsite. 3.1. Compost Manufactured Topsoil (CMT) . After excavation and embankment work is complete, remove and dispose of objectionable material from the topsoil before blending. Use equipment capable of blending CMT uniformly to the full depth as specified. Roll the CMT using a light corrugated drum. 3.2. Erosion Control Compost (ECC) . Use only on slopes 3:1 or flatter. Apply a 2- in. uniform layer after excavation and embankment work is complete unless otherwise shown on the plans or directed. Use a light roller or other suitable equipment when rolling is specified. 3.3. General Use Compost (GUC) . Apply in a uniform layer as a top dressing on established vegetation to the depth shown on the plans. Do not bury existing vegetation. Apply GUC as a backfill ingredient, in a planting soil mixture, for planting bed preparation, or as mulch, when shown on the plans.
4.MEASUREMENT This Item will be measured by the 100- ft. station along the baseline of each roadbed, by the square yard, or by the cubic yard in vehicles at the point of delivery. For ECC cubic yard measurement, the quantity will be the composite material, compost and topsoil or wood chips.
5.PAYMENT The work performed and materials furnished in accordance with this Item and measured as provided under “Measurement” will be paid for at the unit price bid for “Compost Manufactured Topsoil,” “Erosion Control Compost,” and “General Use Compost” as follows . For measurement by the station and square yard, payment will be for the depth specified. For me asurement by the cubic yard, payment will be made for material measured in vehicles. This price is full compensation for loading, hauling, stockpiling, blending, placing, rolling, sprinkling, equipment, labor, materials (including topsoil for CMT and wood chips for ECC), tools, and incidentals. Costs associated with passing quality assurance testing will be paid for in accordance with Article 9.7., “Payment for Extra Work and Force Account Method,” at invoice price with no markups .
Source: Texas Standard Specifications for Construction and Maintenance of Highways, Streets, and Bridges, 2024 Edition. Pages 134–135 of 1,034.