CLEAN WATER is a vital commodity in the semiarid environment within the coastal plain of southern California. About two-thirds of the water supply is imported from often great distances and at significant expense to support the region’s industrial, agricultural and population base. This makes local ground and surface waters a vital resource that needs special attention and protection.
The Chino Groundwater Basin is one of the largest sources of groundwater in southern California. The basin encompasses approximately 220 square miles of the upper Santa Ana River watershed, offering the ability to store up to 500,000 acre feet of water which is enough to virtually “drought proof” the region and reduce its reliance on imported water during droughts.
The Chino Basin is also home to the largest concentration of dairies in the world consisting of over 300 dairy farms and over 400,000 cows, heifers and calves. These dairies produce over 1,000,000 tons of manure annually (based on 70 percent dry weight) with additional manure stockpiles of over 2,000,000 tons on the ground. Over the years, agricultural runoff has impacted local groundwater reserves, resulting in elevated levels of salts, dissolved solids and nitrates, making it unsuitable for direct human consumption without further treatment. In addition, the manure creates air quality concerns relating to dust, odor and volatile organic compounds (VOC) emissions.
CHINO BASIN ORGANICS MANAGEMENT STRATEGY
Unmanaged, these organic wastes would continue to degrade local ground and surface waters. The need to protect the watershed’s valuable waters and allow an important local industry to remain vibrant has resulted in the need to develop creative ways of managing the organic wastes. As the manager of this watershed, the Inland Empire Utilities Agency (IEUA) realized the importance of finding solutions to these issues.
The IEUA is a public water and wastewater utility that supplies imported water and recycled water and collects, treats and disposes of wastewater for six cities and two water districts. It is also responsible for water quality protection. Approximately 700,000 people reside in the agency’s service area which includes the communities of Chino, Chino Hills, Fontana, Montclair, Ontario, Rancho Cucamonga, and Upland. The service area also overlies the Chino Groundwater Basin. It owns a cocomposting facility for dairy manure and biosolids and owns and operates four wastewater treatment facilities. These facilities have a combined treatment capacity of 53 millions gallon per day producing tertiary treated effluent and 180 wet tons/day of Class B biosolids.
Two years ago, the IEUA began a comprehensive planning and analysis effort to review its management options. Out of this effort and through the assistance of Tetra Tech ASL, IEUA’s program manager, a plan was developed that was called the “Chino Basin Organics Management Strategy.” This strategy established a direction to protect the water resources in the basin by pursuing a comprehensive management system of the organic wastes produced in the watershed including animal manures, biosolids, green wastes and food residuals. It also emphasized the production of renewable energy through the anaerobic digestion of the abundant organic wastes in the region.
A START WITH COCOMPOST
A number of additional key factors were taken into consideration while developing the overall program. The first of these was the rapid urbanization of the region. Housing developments were encroaching on the existing cocomposting facility that was constructed in 1995. Using outdoor turned windrow technology, the facility was designed to handle the IEUA’s biosolids along with local dairy manure. The facility is jointly run by two operators, Synagro Technologies and Earthwise Organics. (See “Composter Moves Nutrients, Organic Matter From Generators To Users” in this issue.) The operators are successfully composting and marketing up to 20 percent of locally generated dairy manure to agricultural operations outside of the watershed. The facility also composts and markets all of the IEUA produced biosolids. The concerns with the site centered on increasingly more stringent regulations and approaching development in the direct vicinity of the composting facility. The combination of these factors will result in having to relocate and upgrade the existing compost facility.
A second factor is the protection of groundwater quality. The biggest concern is the dairy industry’s impact on groundwater quality. To mitigate this, there is a need to export the organic matter, nitrates and salts present in the manure outside the watershed to be beneficially reused in agriculture and minimize local groundwater impact. The population of dairy cows peaked in the Chino Basin in the early 1990s. Since then there has been a small downward trend in cow population that is projected to continue through 2015. Nevertheless, the projections developed for 2015 estimate manure production at about 55 percent of current levels. This is based on the premise that many of the current dairies will relocate to other regions of the state or country and sell their Chino Basin farms to real estate developers. This trend is hard to predict due to recent difficulties in finding other regions that are welcoming new dairies, thereby slowing relocation efforts. There will be a continued need to haul the manure from the Basin or process the manure to minimize any impact to the ground and surface waters.
LONG TRACK RECORD IN ANAEROBIC DIGESTION
A third factor is availability and cost of energy supplies. California recently underwent severe disruptions in its electrical energy market resulting in rolling service blackouts and more recent price hikes. The IEUA has had a long track record in anaerobic digestion of its biosolids at its waste-water treatment plants using the resulting methane to power cogeneration systems that offset about 60 percent of its electrical requirements. The ability to expand on this program and include additional local organics such as manure, food and green waste was looked at as a very promising alternative to gain greater energy self-sufficiency while improving air and ground water quality at the same time.
A fourth factor was more restrictive regulations and ordinances dealing with the beneficial reuse of biosolids in California. The trend has been clearly toward Class A treatment with some counties attempting and some succeeding in installing outright bans on Class B land application. Furthermore, the terms of California’s AB 939 regulations requiring 50 percent diversion of wastes from the landfill were further incentive to recycle organic waste streams such as green and food wastes via composting or digestion.
A fifth factor is air pollution emissions from the Chino dairies that are a significant source of dust, ammonia and VOC and diesel resulting from trucking the material out of the region. This is an important issue with regional air quality regulators due to the tremendous efforts to improve all of southern California’s air quality.
After identifying the key factors, the next step in the process was to establish policy objectives outlining the major goals to be accomplished. They are as follows: Produce through anaerobic digestion enough methane gas for 50 megawatts of clean, renewable electric energy by 2006; Cost-effectively recycle organic wastes into fertilizer products in environmentally safe enclosed facilities for local use as a first priority; Reduce air and water pollution; Implement strategies that minimize diesel truck trips; and Accomplish the above goals in a manner that does not financially impact the Regional Sewerage Program.
A business plan was drafted outlining the specific actions to be taken to accomplish the key policy objectives. The focus was on the creation of regional “organic management centers.” That would allow the region to achieve self-sufficiency in the management of its organic residuals via composting and anaerobic digestion, producing organic fertilizer and renewable energy. An important first step in the implementation of the business plan recommendations was the development of pilot demonstration projects. The pilots will provide real world cost and operating performance information that will be critical in building the full-scale facilities. There was also an emphasis on development of public and private partnerships recognizing the role that the private sector plays in bringing technology, markets, capital and expertise to the process. The end result is direct water and air quality benefits through accomplishment of these objectives.
Recognizing the need for public support from all the stakeholders involved was an early priority and taken very seriously. These stakeholders included the surrounding public, regional and state regulatory officials, elected political representatives, environmental organizations and the IEUA’s own member communities. It was an important priority to have these stakeholders participate in the planning efforts and feel part of the decision making process.
Based on the magnitude of the problem, the IEUA’s ambitious plan has received substantial financial support from a variety of state and federal agencies. Initial funding was earmarked to develop the pilot demonstration projects. Sources of funding and amounts have been as follows: California Energy Commission – $8.4 million plus rebates of $1.5 million for installation of electrical generating equipment using renewable methane gas as a fuel source; United States Department of Agriculture, Natural Resource Conservation Service – $4.9 million, FY 2001, $5million, FY 2002; South Coast Air Quality Management District – Six Capstone Micro turbines plus installation costs; and United States Department of Energy – $2.5 million for renewable energy through anaerobic digestion.
Fundraising is ongoing and additional capital will be required to continue progress on implementation of the business plan concepts.
PILOT DEMONSTRATION PROJECTS — UPDATES
The IEUA has ambitious plans to build and operate multiple pilot demonstration projects showcasing a combination of unique composting, anaerobic digestion and renewable energy technologies. The status of the current pilot projects are as follows: Mix fresh dairy manure with municipal biosolids and anaerobically digest the mixture at thermophilic temperatures at one of the IEUA’s regional wastewater treatment facilities. The IEUA digester has been retrofitted and is in start-up; Demonstrate a United States based mesophilic anaerobic digestion technology on dairy manure. A team led by Synagro was selected and constructed a plug-flow digester reactor in three months. The facility is completed and in start-up (see sidebar); Demonstrate anaerobic digestion of cow manure using covered lagoon technology. Doug Williams from Cal Poly San Luis Obispo is leading the design effort and the facility is projected to be completed and operational in 2002; and Construct an enclosed composting facility to process biosolids, green waste and cow manure demonstrating the use of indoor aerated static pile composting followed by biofiltration for odor control. It is currently in the design phase and scheduled to be constructed in 2002. Based on the success of this pilot program, it is the intent to build a number of full-scale enclosed compost facilities.
IMPACT ON WASTE MANAGEMENT SOLUTIONS
The development of the Chino Basin Organics Management Strategy has been accomplished through multiple public/private partnerships between the dairy industry, local cities, private firms (Synagro) and IEUA. In addition, the state and federal agencies have been very supportive in encouraging the implementation of the pilot demonstration projects through financial grant assistance and fast-tracking regulatory approvals. In December, 2001, USEPA Region IX awarded IEUA an environmental award for the Organics Management Strategy. Through our Peer Review Panels and evaluation of the pilot demonstration projects, we hope that the experience learned in the Chino Basin can be successfully applied to similar organic waste management situations in other parts of the United States.
Rich Atwater is CEO and general manager of the Inland Empire Utilities Agency in Chino, California. Paul Sellew is executive president and manager of Synagro Technologies Agribusiness Services Group based in Houston, Texas.