Ordering Information: Call Chief Operator John Lazelle at 802-464-3862
Composting Process
We use equipment purchased from Green Mountain Technologies in 1996, and have been using this in-vessel composting system since 1994. The first step in the process is to dewater the sludge which is accomplished by our new Ecomat Rotating Belt Filter which was installed as a part of our refurbishment project in 2016.
After the sludge is dewatered, we mix it with woodchips at about a 2 or 3 to 1 ratio of woodchips to sludge depending on the moisture content of the sludge and woodchips. After mixing the material is conveyed into the Comptainer.
Aeration tubes are connected and a built in computer is restarted to start the composting process. The computer reads data from temperature probes that are inserted into the sludge/woodchip mixture and regulates the temperature inside the Comptainer to insure that a uniform temperature is maintained throughout the Comptainer. To meet EPA regulations, the mixture must reach a temperature of 55 degrees Celsius (131 F), for three consecutive days. This is known as the “procedure to further reduce pathogens” (PFRP). The mixture must also maintain a temperature of 45 c or 113 f or 14 consecutive days to obtain proper (VAR) or “vector attraction reduction”. The mixture stays in the Comptainer for approx. 21 to 30 days, then is dumped using a roll-off truck and allowed to cure and the necessary laboratory analysis are completed. After curing and analysis are complete, the final product is given to Wilmington residents free of charge. Delivery is free to Wilmington residents. The product is used mostly as a mulch for flower gardens or as a soil conditioner. It is a class A compost, but is not certified to be used in vegetable gardens.
TOWN OF WILMINGTON WASTEWATER TREATMENT PLANT
BIOSOLIDS COMPOST (2022)
The biosolids compost product produced by the Town of Wilmington can be used in a number of applications as a soil conditioner and fertilizer. The product is partially derived from sewage sludge that is treated to exceptional quality biosolids standards by high temperature composting a mixture of wastewater treatment plant sludge and woodchips. The finished compost is uniform in color, texture and quality. Below you will find suggested methods of application and information regarding the characteristics of the compost. The product is defined by the State of Vermont as an “Exceptional Quality biosolids” and is not classified as a solid waste once distributed.[1]
COMPOST CHARACTERISTICS:
Wilmington Compost provides landowners, nursery operators, landscapers, greens keepers, general contractors, and others with an alternative to commercial fertilizers, and gives them an opportunity to recycle nutrients into the environment. Plants benefit from the nutrients: nitrogen, phosphorus, and potassium and various micronutrients within the compost.
See the tables for typical nutrient and the metal concentrations in Wilmington compost. Metal concentrations are well below the standards set by the State of Vermont Agency of Natural Resources and the U.S. Environmental Protection Agency. The product may contain per- and polyfluoroakyl substances (PFAS).
METAL CONTENT IN WILMINGTON COMPOST
(mg/kg dry weight)
| METAL | VT. STANDARDS | WILMINGTON COMPOST 2021 AVERAGE |
| Arsenic (As) | 15 | 5.31 |
| Cadmium (Cd) | 21 | .95 |
| Chromium (Cr) | 1200 | 6.24 |
| Copper (Cu) | 1500 | 110 |
| Lead (Pb) | 300 | 13.45 |
| Mercury (Hg) | 10 | .11 |
| Molybdenum (Mo) | 75 | 2.12 |
| Nickel (Ni) | 420 | 5.83 |
| Selenium (Se) | 100 | 10.6 |
| Zinc (Zn) | 2800 | 210 |
OTHER REQUIRED PARAMETERS
(mg/kg dry weight unless otherwise specified)
| PARAMETER | VT. STANDARDS | WILMINGTON COMPOST 2021 AVERAGE |
| Total polychlorinated biphenyls (PCB) | 1 | <.20 |
| Fecal Coliform | 1000 (MPN/G) | 350 (MPN/G) |
| pH | n/a | 6.75 (pH units) |
| PARAMETER | VT. STANDARDS | WILMINGTON COMPOST 2021 AVERAGE |
| Percent Solids | n/a | 39 (%) |
| Total Nitrogen (TN) | n/a | 20,450 (2.05%) |
| Total Phosphorus (TP) | n/a | 1,375 (.14%) |
| Total Potassium (TK) | n/a | 1,925 (.19%) |
Table source: Compost values are from analysis of Wilmington Compost in 2021.
SUGGESTED METHODS OF APPLICATION
LAWN MAINTENANCE: Top dress 1/3 inch of compost (approx. 1 cubic yard per 1000 square feet) on established lawn and rake. A mixture of compost and sand may also be used as a top dressing.
Topsoil Production of Lawn and Garden Establishment: Mix up to one-part compost with three parts soil by volume. Less compost is required with more fertile soils.
SHRUBBERY AND TREE PLANTING:
Uniformly mix compost with existing soil at a rate of one-part compost to four parts soil by volume and use as backfill. Soils with previously established shrubs may be top dressed with the compost as a maintenance fertilization.
DISCLAIMER:
There are no warranties, expressed or implied, that extend beyond the information in this brochure. The Town of Wilmington makes no warranty of merchantability or fitness of this compost for any other purpose than as described. Accordingly, and without limitation, there is no warranty, expressed or implied, as to quality or productivity of any compost, and the Town of Wilmington is not responsible for any alleged damage from the application of the compost. Composted sludge, like composted manure, is hygienically and environmentally safe when used properly. Compost, like any fertilizer or soil amendment, should be stored in a protected area away from children and animals, or where it may be washed into streams.
ORDERING INFORMATION:
The biosolids compost product is unscreend, free to Wilmington residents and there is a 4 yard minimum order. SUPPLY IS LIMITED FIRST COME – FIRST SERVED!
We will call before delivery to confirm where the compost should be dumped. Site must be either clearly marked or someone there to direct us.
To place an order or for more information, contact John Lazelle 802-464-3862 jlazelle@wilmingtonvt.us
TOWN OF WILMINGTON
WASTEWATER TREATMENT PLANT
P.O. BOX 217
WILMINGTON, VT 05363
[1] RESIDUALS MANAGEMENT & EMERGING CONTAMINANTS PROGRAM
https://dec.vermont.gov/waste-management/residuals-management
https://wilmingtonvermont.us/departments/wastewater-treatment-plant/
For more information or to order a load of Compost, please fill out the form below!