Protecting Water Quality and Promoting Economic Efficiency at Agricultural Composting Facilities

Final Report for OW10-329

Project Type: Professional + Producer
Funds awarded in 2010: $49,115.00
Projected End Date: 12/31/2011
Region: Western
State: Oregon
Principal Investigator:
Nick Andrews
Oregon State University
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Project Information


This project sought to assist farmers in meeting mandatory composting regulations adopted in 2009 by the Oregon Department of Environmental Quality (DEQ). This project developed a publication and resources for the web; conducted outreach such as workshops, a focus group and a survey of experienced composters; and encouraged growers to adopt BMPs that protect water quality while composting in an economically viable way.


In 2009, DEQ adopted new rules for composting facilities in Oregon. Under these rules, Oregon’s farmers are required to manage environmental risk at their composting sites. Oregon State University (OSU) faculty had represented the interests of agricultural composters at the rule-making meetings to avoid requirements that agricultural composters operate under the same guidelines and permitting system as industrial composters.

When well-managed, agricultural composting improves soil structure and soil fertility and supports regional organic waste recycling goals. In our region, compost feedstock is often generated in late summer and fall, and compost piles are built in the fall and managed during wet weather. Water quality can be impacted by poorly managed compost facilities, especially as the scale of the agricultural composting operation increases. Some farmers have developed low-cost and effective techniques for minimizing the environmental risk of composting.

The cost of environmental controls at agricultural composting facilities has the potential to inhibit on-farm composting. The overall goal of this project was to provide agricultural composters with opportunities to understand the intent and process of Oregon’s composting regulations and feel more confidence in that process.
Specific objectives of the project were to: 1) educate farmers on environmentally sound composting methods, 2) educate regulators on the differences between industrial and agricultural composting, 3) provide a collaborative, participatory environment in which the two groups gained knowledge of the others’ context and experience, 4) organize and deliver farmer focus sessions and farm visits to identify promising management alternatives to protect water quality, and 5) draft an extension best practices guide, informed by project partners.

A formal literature review was performed in preparation of publication output of this project: Agricultural Composting and Water Quality. The resultant bibliography can be found at the end of this report.

Project Objectives:
  1. Conduct two agricultural composting tours. Ultimately, farmers preferred not to host a tour of their composting operations. Instead of the tours, farms were visited for individual consultation. In effect, the tour came to farmers, instead of farmers going to the tour.

    Conduct two focus group interviews. An initial focus group interview was held 2/25/11. This session provided interested growers the opportunity to give suggestions for project direction and focus. A few of the farmers participating in this initial meeting became integral parts of on-going project and participated in review of the project publication: Agricultural Composting and Water Quality. One focus group outcome was restructuring the approach for project interaction with the farmer group for the remainder of the project. Project participant interviews were conducted on a farm-by-farm basis. This approach included more farmers than would attend meetings, and by allowing project personnel to see the composting site rather than speaking in generalities, it provided opportunities for better communication.

    Obtain grower input on BMP manual. Done.

    Complete individual farmer interviews about composting practices and perception of the regulatory process. A standardized survey, approved by OSU Institutional Review Board, was the instrument used to gather data about existing on-farm composting facilities and grower intentions for water quality protection at these facilities in the future. Survey administration permitted farmers to ask questions of project personnel that might not be raised in a group meeting. The survey allowed data to be summarized without revealing specifics about individual composting operations. Done.

    Analyze and interpret survey results. Done.

    Complete and disseminate final BMP manual, which reflects farmer input. Done.

    Post link to final BMP manual on project website: Agricultural Composting and Water Quality, EM 9053, Oregon State University Extension Service. Will do.

    Build and maintain project website. In process.


Click linked name(s) to expand/collapse or show everyone's info
  • Nick Andrews
  • Bob Barrows
  • David Brown
  • John Eveland
  • Jeff Gage
  • William Matthews
  • Brennan McMillen
  • Peter Moon
  • Dr. Dan Sullivan
  • Wali Via
  • Bob Wilt


Materials and methods:
Objective 1: Participatory Process.

An initial focus group interview was held 2/25/11. This session provided interested growers the opportunity to give suggestions for project direction and focus. A few of the farmers participating in this initial meeting became integral parts of on-going project and participated in review of the project publication: Agricultural Composting and Water Quality. One focus group outcome was restructuring the approach for project interaction with the farmer group for the remainder of the project. Project participant interviews were conducted on a farm-by-farm basis. This approach included more farmers than would attend meetings, and by allowing project personnel to see the composting site rather than speaking in generalities, it provided opportunities for better communication.

Methods used for participatory process implementation are reported under Objectives 2 and 3 (below).

Objective 2: Survey.

In face-to-face or telephone interviews, 26 established agricultural composters responded to 43 IRB-approved survey items intended to describe their operations, feedstock, reasons for composting, practices to prevent or control leachate and their attitudes about the regulatory environment within which they practice on-farm composting. Appendix 1 is the survey instrument as administered; Appendix 2 is selected survey findings.

Objective 3: Publication.
  • Content Development: Publication content was developed gradually, in parallel with the collection of compost survey data (see Objective 2). Development of content for the “BMP manual” was enhanced by collaboration among farmers, extension faculty and regulators in a series of educational short courses conducted under other funding. These workshops, “ACRES” (Agricultural Composting Resources & Education Series;, provided an opportunity for a shared experience among collaborators involved in preparing the BMP manual. Workshops were small (about 30 participants and 5+ instructors), allowing for in-depth discussion of relevant topics. ACRES workshop interactions helped the project team to identify the questions on-farm composters have and which issues the regulators think are most important for protection of water quality. The ACRES workshops provided an opportunity to identify water quality publication topics, to evaluate common composting practices and to identify contributors to the “Agricultural Composting and Water Quality” publication to meet identified audience needs. The workshop experience helped to develop a shared knowledge base among SARE project participants and to strengthen existing relationships and partnerships.

    Writing and editing. Chapters were prepared by extension educators in collaboration with farmers and composting consultants. A draft was circulated in fall 2013 for review by all members of the project team and by selected external reviewers. The manual was sent to a technical editor for review of grammar, style and clarity, and layout in January 2013. Several versions of the layout version of the publication were reviewed by authors and by external reviewers to ensure clarity, consistency and flow in spring of 2013.

    Publishing. The publication will be a numbered publication under the auspices of OSU Extension and Experiment Station (official publisher for OSU). As such, it will be reviewed and updated on a five-year cycle. It will have a permanent URL at OSU Scholar’s Archive. So the benefit from the first edition of this publication (funded by this SARE project) will be present for many years.

Research results and discussion:

Outcomes for project participants were:

*Increased farmer understanding of water quality risks associated with composting and practical methods for mitigating these risks. This outcome has been delivered through multiple pathways, including on-farm visits, publication of a BMP guide and ongoing ACRES workshops.

*Improved regulator understanding of the limitations and opportunities for managing environmental risk on agricultural composting facilities. The project increased opportunities for regulators to interact with agricultural composters in the BMP guide writing and review process.

*Project outreach has been accomplished by publishing a BMP guide for agricultural composting facilities, by establishing and actively managing a project website, and by incorporating project findings into curricula for the OSU Agricultural Composting through annual composting workshops for farmers and agricultural professionals (ACRES).

*This project strengthened existing partnerships among and between project educators, growers, composting consultants and regulatory agency personnel. Of special value were the opportunities for growers and regulators to come to a greater understanding of one another’s positions. The publication output from this project was enhanced by the broad diversity of project participants who contributed to its scope, content and revision.

From the survey of agricultural composters, we learned that farmers:
  • Want to compost;
    Want to be good environmental stewards;
    Manage composting activities to avoid leachate generation;
    Often do not invest much in infrastructure;
    Want to avoid regulatory entanglements;
    Will accept educational assistance to improve their choices;
    Accept reinforcement of their existing good choices.

This project has benefited Oregon agricultural composters who experienced an on-site visit as a part of the survey process. The publication resulting from this grant was informed by these farm visits. Researchers observed on-farm practices and engaged growers in a discussion of their practices. Growers benefited from the “teachable moments” that arose. These visits reinforced the feasibility of agricultural composting for these producers. See “accomplishments” and “impact” sections for greater detail. See also Appendix 1 and Appendix 2 for more information about and resulting from the survey.

Participation Summary

Educational & Outreach Activities

Participation Summary:

Education/outreach description:

Brewer, L. N. Andrews, D. Sullivan, and W. Gehr. 2013 Agricultural composting and water quality. Oregon State University Extension Service, Corvallis OR. EM 9053.

ACRES Website:

Many individuals contributed to this publication, including farmers, compost consultants, regulators and educators. Each group informed the publication’s concept, identified information needs and actively participated in fact checking and stylistic reviews. This publication provides useful information for agricultural composters in other regions, in a concise format:

  • Chapter 1 On-Farm Composting: What You Need to Know. This chapter discusses two important aspects of developing the composting enterprise: the potential value of compost and regulatory considerations for Oregonians.

    Chapter 2 Site Selection. A guide to thoughtful site selection in order to minimize risks to water quality. A detailed discussion of the characteristics to consider when choosing a site for on-farm composting.

    Chapter 3 Compost Site Layout and Design: This chapter covers the characteristics of good composting sites, how to estimate the area required, and how to organize a composting site for smooth process flow.

    Chapter 4 Choose the Composting Method That’s Right for You. This chapter reviews how to match composting methods to farm resources and available feedstock.

    Chapter 5 The Composting Process and its Impact on Water Quality: This chapter reviews the chemistry, biology and process control for efficient composting, with an emphasis on avoiding leachate production.

    Chapter 6 Manage Runoff and Leachate: This chapter introduces some strategies to manage any leachate that is produced.

    References and Resources

Project Outcomes

Project outcomes:

This project allowed OSU faculty to work collaboratively with agricultural composters, DEQ and Oregon Department of Agriculture. Knowledgeable representatives from each of these agencies contributed to the BMP review and ensured that regulatory information provided to growers was complete, accurate and readily actionable. Farm visits included an educational component, as survey administrators discussed and observed composting principles in general, and a consultant component as they gave specific advice relevant to on-site conditions.

By drawing on the expertise of respected growers who adopt scale-appropriate, conservative practices, this project has

*strengthened existing faculty-grower relationships through collaboration in an inherently engaging endeavor;
*demonstrated to regulatory agencies that on-farm composting can be infrastructure-light and environmentally-conservative;
*educated growers and regulators on the other’s point of view;
*strengthened grower – regulator - educator relationships.

Economic Analysis

The project did not attempt to measure economic impacts, but some of the related costs that can be avoided include:

*Fines from leachate impacting surface or ground water;
*Cost of environmental controls (ie, concrete pads, roofs, leachate treatment ponds) at agricultural composting facilities that could have been imposed by regulatory agencies;
*Purchased animal bedding;
*Disposal cost for organic wastes;
*Fertilizer, compost, mulch purchases;
*Potting mix component purchases;
*Economic benefits that could accrue from adoption of these practices;
*Sale of compost;
*Tipping fees for receipt of organic wastes;
*Market premiums for organic or transitional fruits and vegetables – NOP requires soil building.

Farmer Adoption

Number of farmers reached: 200

Recommendations for day to day operations:

*Growers should familiarize themselves with the Oregon DEQ composting rules as they apply to grower activity.

*Thoughtful site selection and process control planning will pro-actively address many of the water quality issues that could result from composting.

*Growers will benefit economically from tracking their composting activities and adjusting their methods as experience, feedstock volume and access to capital permit.

Farmers should stop:

Our work with growers and the survey results did not reveal widespread practices having egregious water quality impacts. Rather, as a result of this project, growers have become more aware of the DEQ rules and have been led to optimize composting practices to their own benefit and to the stewardship of the environment.


Areas needing additional study

We found the participatory process very effective in bringing together growers and regulators to explore policies and practices of common interest. We would strongly support similar opportunities to seek solutions between these groups.

Growers appear to have an inexhaustible enthusiasm for composting outreach events. Perhaps this enthusiasm could be tapped into to promote other soil and water quality practices.

Other Western SARE-funded work addressing the release of soil nutrient from compost over time continues to draw interest from a similar cohort of growers, as those attracted to the compost work. Soil systems are highly dynamic and complex. Continued research in this area would add to the body of knowledge and perhaps become of greater value as the climate continues to change.

Information Products

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.