Community-Scale Composting Systems: A Comprehensive Practical Guide for Closing the Food System Loop and Solving Our Waste Crisis
review by Bob Banning
Almost fifty years after the first Earth Day, enormous amounts of food scraps are still wasted instead of being returned to the soil, where they belong. James McSweeney wants to be part of the solution by helping people develop successful community-scale composting systems that focus on food scraps, and with this richly detailed manual you can benefit from the composting expertise he has acquired over many years of working with hundreds of composters managing every phase and aspect of the composting process and the composting enterprise.
McSweeney believes that such expertise is urgently needed because in the last five to ten years he has witnessed an acceleration in the rate at which new community composting enterprises are being started—to the point where we have a community composting “movement.” The more new composting enterprises there are, the more opportunities there are for people to make mistakes—some of them system-wrecking—that could have been avoided if the operators had the necessary knowledge, knowledge that’s available if you know where to look. McSweeney wants to get the word out about known best practices so that more and more communities will not just try, but succeed at composting.
Although I am only am amateur composter and thus cannot evaluate the book on the basis of experience in the industry, I have read quite a bit about composting through the years, even subscribing to BioCycle for a year. On the basis of that amateur perspective, to me it looks like McSweeney put together a very thorough guide.
Chapter 1 outlines composting models. If members of a community want to compost, they find a way, and McSweeney rejoices in the many creative ways that people have found to work together and make composting happen: composter networks, on-farm composting, commercial composting, schools and other institutions, community gardens and farms, worker cooperatives, demonstration and training sites, collection services, drop-off programs, and home composting initiatives.
Chapter 2 describes leading methods and technologies, enumerating advantages and disadvantages of each. Chapter 3 explains the composting process, including what composting requires in terms of food (for the microbes), air, water, and warmth. The author emphasizes that if you want to produce a salable product, your compost must be “thermophilic”—hot. Specifically, it should meet the standards of the National Organic Standards Board, maintaining a minimum temperature of 131°F/55°C for at least three days.
Chapter 4 tells you how to choose feedstocks and combine them into a recipe that works. The author discusses carbon-to-nitrogen ratios, moisture content, bulk density, porosity, particle size, and pH. He suggests sources for various feedstocks. He warns of contamination and advises about how to avoid it.
In chapter 5 the book lays out steps for deciding how much processing capacity you want, understanding what characteristics you’ll need in a site in order to reach that capacity, and then determining what is the potential processing capacity of a given site that you’re considering.
Chapter 6 explains infrastructure and equipment needs. Among other things, we learn that concrete is best for receiving and blending areas, we learn about mixing and turning equipment, and we read about kinds of shelters for keeping your carbonaceous feedstock dry.
Chapters 7-11 give detailed treatments of specific methods. A chapter is devoted to each of the following: bin and bay, turned windrow, aerated static pile, and in-vessel systems and systems that compost with animals. McSweeney favors the aerated static pile (ASP) system because of its efficiency: with this method, you can produce finished compost in half or even a third of the time it takes to do so with a turned windrow system. In an ASP system, perforated pipes or ductwork is run underneath the pile, and the necessary oxygen is supplied by the use of blowers that force air through the pipes or ducts.
Chapter 12 deals with food scrap generation and collection, chapter 13 treats site management, and chapter 14 enumerates end uses and markets for compost and helps you think about how to connect with those markets.
Throughout the book, McSweeney walks readers through complex information by manageable steps, with the aid of tables, charts, sample calculations, checklists, worksheets, inset texts with case studies, photos, other graphics, and cross-references. Abundant subheadings in every chapter make it easy to find the topic you’re looking for.
The back-of-book matter has a page of information resources, including the URL for the author’s website. Nine pages of endnotes show that his advice is grounded in knowledge of scientific and trade literature as well as on-the-ground experience.
Since, as a literary genre, the manual is not generally looked to for entertainment, I will add that the author has an engaging, welcoming style that reflects a passion for composting, joy in seeing communities thrive, and a healthy sense of humor. Walk into the introduction, sit down, and let him tell you about composting. I think you’ll be glad you came.