Mon-Fri: 8am-5pm


Compost Process


How To Buy Compost

Compost is available to the Big Sky community for $25 per yard. Please contact the Big Sky Water & Sewer office for details.


Municipal Compost

All of the municipal wastewater sludge produced at Big Sky’s new wastewater treatment plant is post-processed into a compost product that meets all of the EPA standards for land application.  The decision to make compost is consistent with other decisions to make us a treatment facility that is 100% self contained.  All of our wastewater is treated and stored through the winter months.  During the summer months 100% of the treated water is reclaimed for use as irrigation water on 2 golf courses here.  The result is a zero discharge facility, so not one drop is discharged to the Gallatin River. Rather than pay to truck our wastewater by-product sludge waste and a have it hauled down the canyon to be land spread on farm fields, the District decided to construct a state of the art compost facility. Our goal is to make compost that is:


  • Inexpensive
  • Safe to use
  • Meets all federal and state standards
  • Beneficial for use as ornamental landscaping cover
  • Fertilizer for gardens and lawns

Compost Lab Analysis

Compost Lab Analysis – 2008

The District sent a new sample of its compost to the Control Laboratories located in Watsonville California on January 24, 2008.  This lab specializes in analyzing soil and compost products.  This analysis covered many nutrients and metals.

A copy of the lab analysis summary sheet is shown below.  Click here for PDF file format of the full lab analysis that includes an index:

Control Labs also has a website that has more informaiton about the compost lab testing.

Compost Lab Analysis – 2005

On September 22, 2005, the District sent a sample of finished compost to Energy Laboratories Inc. in Billings to perform a lab analysis on a finished compost sample.  This analysis covered the following parameters:

  • Compost Metals by ICP/ICPMS, Total or Soluble
  • Bacteria, Fecal Coliform-sludge
  • Moisture, % Dry Basis
  • Ammonia as N, KCL Extract
  • Nitrate as N, KCL Extract
  • Total Kjeldahl Nitrogen
  • Nitrogen, Total
  • Organic Carbon, Compost, %
  • Digestion, Total Metals
  • Total Sulfur

A copy of the lab analysis summary sheet is shown below.  Click here for PDF file format of lab analysis:

If you have any questions regarding these tests results, please call Energy Labs at 1-800-735-4489 or email them at