CHAPTER 5 INDUSTRY SUBCATEGORIZATION FOR EFFLUENT LIMITATIONS GUIDELINES AND STANDARDS 5.0 INTRODUCTION The Clean Water Act requires EPA to consider a number of different factors when developing Effluent Limitations Guidelines and Standards (ELGs) for a particular industry category. These factors include the cost of achieving the effluent reduction, the age of the equipment and facilities, the processes employed, engineering aspects of the control technology, potential process changes, nonwater quality environmental impacts (including energy requirements), and factors the Administrator deems appropriate. One way EPA takes these factors into account is by breaking down categories of industries into separate classes of similar characteristics. The division of a point source category into groups called “subcategories” provides a mechanism for addressing variations among products, raw materials, processes, and other parameters that result in distinctly different effluent characteristics. Regulation of a category by subcategory ensures that each subcategory has a uniform set of effluent limitations that take into account technology achievability and economic impacts unique to that subcategory. The factors that EPA considered in the subcategorization of the CAFO point source category include: • Animal production processes • Waste management and handling practices • Wastes and wastewater characteristics • Waste use practices • Age of equipment and facilities • Facility size • Facility location EPA evaluated these factors and determined that subcategorization of this point source category is necessary. Based on these evaluations, the CAFO point source category has been divided into four subcategories for the purpose of issuing effluent limitations. These four subcategories are: • Subcategory A (Subpart A): Horses and sheep 5-1 • Subcategory B (Subpart B): Ducks • Subcategory C (Subpart C): Dairy and beef cattle other than veal calves • Subcategory D (Subpart D): Swine, poultry, and veal calves Section 5.1 briefly discusses the background of the subcategorization of the CAFO point source category including the 1974 Feedlots ELG. Section 5.2 discusses the subcategorization basis of the CAFO industry. 5.1 Background Under the 1974 rulemaking, EPA divided the point source category into two subcategories: (1) Subpart A - all subcategories except ducks, and (2) Subpart B - ducks on dry lots and wet lots. Subcategories addressed under Subpart A include • Beef cattle, open lot • Beef cattle, housed lot • Dairy cattle, stall barn with milk room • Dairy cattle, free stall barn with milking center • Dairy cattle, cowyard with milking center • Swine, open dirt or pasture lots • Swine, housed with slotted floor • Swine, open or housed with solid concrete floor • Chickens, broilers housed • Chickens, layers (egg production) housed • Chickens, layer breeding and replacement stock housed • Turkeys, open lot • Turkeys, housed lot • Sheep, open lot • Sheep, housed lot • Horses, stables This subcategorization was developed primarily on the basis of animal type and production processes employed. Secondary criteria were product produced, prevalence of the production process employed, and characteristics of waste produced. 5-2 On January 21, 2001 (66 FR 2960), EPA published a proposal to revise and update the ELG for feedlots (beef, dairy, swine, and poultry operations) that included two new subcategories: • Subpart C: Dairy and beef cattle, other than veal calves, including heifer operations. • Subpart D: Swine, poultry, and veal calves. This subcategorization scheme explicitly addressed immature cattle and swine weighing less than 55 pounds, which were not explicitly included in the previous subcategorization scheme, and established new subcategories for swine, poultry, and cattle operations (separate from horses and sheep). The proposal did not affect Subpart B, and retained Subpart A for horses and sheep. 5.2 Subcategorization Basis for the Final Rule The CAFO industry has changed operational practices considerably in the past few decades since promulgation of the 1974 ELG. During the development of this revised ELG, EPA determined that the basis for subcategorization needed to reflect current industry trends. In developing the final CAFO rule, EPA used information from USDA, industry, EPA site visits, data from EPA enforcement and inspection efforts, and public comments to evaluate each of the statutory factors listed above in Section 5.0 as they affect the current industry. EPA also considered maintaining the basis of subcategorization used in the 1974 ELG and refining the performance expectations for these facilities. Based on these analyses, EPA retained the subcategorization scheme proposed on January 21, 2001. The subcategories are • Subpart A: Horses and sheep. • Subpart B: Ducks. • Subpart C: Dairy and beef cattle, other than veal calves, including heifer operations. • Subpart D: Swine, poultry, and veal calves. The remainder of this section discusses the factors considered for the subcategorization of the CAFO industry and those that were selected as the basis of the final subcategories. 5.2.1 Animal Production, Manure Management, and Waste Handling Processes Production processes in the CAFO industry include all aspects of animal husbandry, animal housing, and type of animal operation. The type of production process, including animal type and housing, was one of the primary levels of subcategorizing the industry in the 1974 ELG. Furthermore, the waste handling and manure management practices at CAFOs are closely tied to housing practices and support the rationale for using these processes as a basis for subcategorization. As discussed in Chapter 4, Large beef feedlots, dairies, and heifer operations typically have outdoor confinement lots where animals are housed for all or at least a portion of their time. Large beef, dairy, and heifer operations keep animals in confinement on outdoor lots 5-3 and generate and manage both solid manure and liquid process wastewater that are affected by climate, especially precipitation. More specifically, the majority of Large beef feedlots are open feedlots, which are usually unpaved. These types of operations may use mounds in the pens to improve drainage and provide areas that dry quickly, because dry resting areas improve cattle comfort, health, and feed utilization, all of which contribute to efficient animal weight gain. In open feedlots, protection from the weather is often limited to a windbreak near the fence in the winter and sunshade in the summer; however, treatment facilities and hospital areas for the cattle are usually covered. Animals are fed two or three times daily, so a concrete apron is typically located along feedbunks and around waterers (i.e., heavy traffic areas). Wastes produced from beef feedlots include manure, bedding, spilled feed, and contaminated runoff. Unroofed confinement areas typically have a system for collecting and confining contaminated runoff. The runoff is typically managed in a storage pond and the manure from the open lots is often scraped and stacked into mounds or stockpiles. Beef feedlots typically use a settling basin to remove bulk solids from the liquid waste stream, reducing the volume of solids before the stream enters a storage pond. The primary function of a dairy is the production of milk, which requires a herd of mature dairy cows that are lactating. In order to produce milk, the cows must be bred and give birth. Therefore, a dairy operation may have several types of animal groups present including calves, heifers, cows that are close to calving, lactating dairy cows, dry cows, and bulls. Animals at dairy operations may be confined in a combination of freestall barns, outdoor dry lots, tie stalls, or loose housing (barns, shades, and corrals). Some animals may be allowed access to exercise yards or open pastures. At dairies, the most common type of housing for lactating cows includes freestalls, dry lots, tie stalls/stanchions, pastures, and combinations of these. Freestalls are the housing systems used by practically all Large dairy operations. The cows are not restrained in the freestalls and are allowed to roam on concrete alleys to the feeding and watering areas. Manure collects in the travel alleys and is typically removed with a tractor or mechanical alley-scraper, by flushing with water, or through slotted openings in the floor (refer to Section 4.3.5 for a more detailed description of waste handling). Dry lots are outside pens that allow the animals some exercise, but do not generally allow them to graze. These milking cows are not likely to spend their entire time in a freestall or on a dry lot, as they need to be milked at least twice a day at a tiestall or in a milking parlor. Most dairies have both wet and dry waste management systems. The dry waste (manure, bedding, and spilled feed) is typically collected from the housing and exercise areas by tractor scrapers and stored where an appreciable amount of rainfall or runoff does not come in contact with the waste. The wet waste (water from the barn and milking parlor cleaning operations, manure, and contaminated runoff) is typically stored in anaerobic lagoons. Like beef feedlots, dairies tend to use solid separators to remove bulk solids from a liquid waste stream. Waste associated with dairy production includes manure, contaminated runoff, milking parlor waste, bedding, spilled feed, and cooling water. Lactating cows require milking at least twice a day and are either milked in their