Issues for Regulating Air Quality on Livestock Operations

Calvin Parnell

Director, Center for Agricultural Air Quality Science and Engineering (CAAQES)

CAAQES website:  http://caaqes.tamu.edu/

Texas A&M University

Introduction:

Appropriate regulation of agricultural emissions of air pollutants is essential. If the EPA and/or state air pollution regulatory agencies (SAPRA) inappropriately fine and require controls to be placed on facilities without the proper justification, the air pollution regulatory process is not functioning properly. The Federal Clean Air Act and similar legislation by state legislatures provide the enabling legislation for states to permit and enforce emissions of air pollutants.  EPA and SAPRA regulating personnel must estimate emission rates using emission factors. Many emission factors for agricultural operations are unknown and/or are not based upon sound science. The emission of air pollutants must be based upon sound science. 

CERCLA vs. CAA:

Recently, three large swine operations reached a $25 million settlement with the US EPA for failure to report ammonia emissions. Since ammonia is not a “criteria pollutant” or a “hazardous air pollutant”, it is not regulated by EPA and SAPRA in a .manner similar to emissions of PM₁₀, NOx, SO₂, etc under the Clean Air Act (CAA). The settlements were a consequence of not reporting the ammonia emissions and the assumption that each of agricultural operations were emitting more than the reportable quantity of 100 pounds per 24-hour period. CERCLA commonly referred to as “Superfund” was cited as the enabling legislation. There are those who question whether ammonia from “naturally occurring” emissions from livestock facilities are appropriately regulated under CERCLA. There is no question that CERCLA and the CAA are two different laws and CERCLA is not a subset of CAA. In general, CERCLA ia a “reporting requirement” with violators subject to $27,500 per day for not reporting. In contrast, the CAA is the enabling legislation for permitting and enforcement of air pollution emissions.

Buckeye Egg:

In 2004, the US EPA fined Buckeye Egg Farm $880,598 and required the owner/operator to invest $1.4 million for controls and monitoring. The justifications for these actions were failure to obtain Title V and Prevention of Significant Deterioration (PSD) permits. The thresholds for requiring Title V and PSD permits are 100 and 250 tons per year of particulate matter less than a nominal 10 micrometers in diameter (PM₁₀). The EPA used measured concentrations and flow rates reported by their contractor to calculate annual PM emissions.  The EPA and contractor made the following serious errors:

• They used measured total suspended particulate (TSP) concentrations rather than PM₁₀ concentrations to calculate annual emissions of PM₁₀. The contractor reported particle size distributions for the Buckeye facility reported to be emitting 740 tons of PM per year. This size distribution was not used. The CAAQES analysis of the contractors reported size distribution suggested that had the size distribution been used, the facility would have been projected to emit less than 10% of the 740 tons per year of PM₁₀ or approximately 74 tons per year. 
• They used inappropriate flow rates through the poultry houses to calculate annual emissions. The contractor reported measured flow rates of 6,300 cubic feet per minute (cfm) per fan. EPA chose to use 14,000 to 16,000 cfm per fan operating for 365 days per year, 24-hours per day. These data were compared to the Midwest Plan Service (MWPS) for flow rates and was significantly higher. Using MWPS recommendations that varied the recommended flow rates depending upon ambient temperature, the total annual flow rate was approximately 40% of the flow rate used by EPA. Using the MWPS flow rates, it is likely that the emission rate of PM₁₀ was 35 tons per year. 

This facility did not meet the threshold for requiring either PSD or Title V permits!

In April, 2005, EPA fined the new owner of these facilities an additional $500,000. 

Sampler Bias:

A subcommittee of the Agricultural Air Quality Task Force (AAQTF) met with Steve Page and a large number of his staff (OAQPS, EPA @ RTP) and addressed the “over-sampling” issue with federal reference method (FRM) PM₁₀ and PM_2.5 samplers in the presence of PM emitted by agricultural sources. This is a consequence of the larger PM characteristically emitted by agricultural operations. For example, FRM PM₁₀ samplers have the potential for an over-sampling error of 225%. This problem is even more pronounced with FRM PM_2.5 samplers. The problem is associated with the use of ambient samplers at the property line of fugitive sources of agricultural PM emissions and the EPA requirement that these concentrations be less than the NAAQS.

Reactive Volatile Organic Compounds (RVOC)Gas:

Pending regulations in California will implement emission standards for reactive organic gases (ROG) or RVOC which are precursors for the formation of ozone. Ozone is a criteria pollutant (a gas regulated under the Clean Air Act).   Current research is limited and inadequate for accurately quantifying the emission rates of Reactive Volatile Organic Compounds (RVOC) emitted from livestock facilities. The concern of researchers and livestock producers is that regulations that could have a significant impact on livestock producers will be established based on emission factors that are not grounded in sound science.

Discussion:

Harry Hoitink (OSU) noted that there was a history of problems at some Ohio layer facilities and emissions, while only part of the problem, provided the means to implement regulatory authority.  Parnell responded that although there were documented management problems at some Buckeye facilities, including ongoing fly and odor complaints, the US EPA was initially involved due to water quality issues.  It is important that any “bad actor” in livestock production be subject to consequences under the appropriate legislation and that good science be used.  If measurements that are neither accurate nor valid are used to impose fines or restrictions, the precedents set will have long term repercussions. 

Kevin Elder (ODA) asked if the methodology/data used by the US EPA to analyze PM₁₀ emissions at Buckeye is still being used.  The Ohio EPA did not agree with those findings but it seems that it is very difficult to correct the problem.  Parnell agreed. 

Maurice Watson (OSU) noted that a California study cite that highways are big contributors to PM_2.5 (2.5 microns).  Parnell agreed that those findings had been made based on measurements along California highways.

Parnell discussed concerns regarding the US EPA proposed NAAQS for PM_coarse (between 2.5 and 10 microns).   The particle size distribution (PSD) for PM emissions from agricultural areas is significantly different compared to those from urban/industrial areas; the mass mean diameter (MMD) for PM from urban areas is 5.7 microns and from rural areas is 20 microns.  Research at the CAAQES indicates that samplers that measure PM₁₀ concentrations can be measure concentrations of up to 300% higher for large MMD compared to those with MMD of 10 microns or less. The sampling error needs to be accounted for before NAAQS thresholds for PM_coarse are established. 

Mike Lilburn (OSU) asked for recommendations to address the problem in poultry facilities where dry conditions increase the potential for greater emissions of PM but wet conditions increase the potential for ammonia emissions.  Parnell responded that it is a problem and requires careful balancing and management.  Currently the CAAQES focuses on PM emissions as they are regulated while ammonia emissions are not.

Diane Borger (OSU) noted that it is disconcerting that the US EPA Region V is still using the data used in the Buckeye Egg decision which is not accurate.  How do you instigate change?  Parnell responded that there have been successes for changing emission standards for cotton gins.  It requires both education and good science that produces valid data.

Seminar summary by Dr. Calvin Parnell

Discussion notes by Mary Wicks

The OCAMM (Ohio Composting and Manure Management) Program is funded by OARDC/OSU.