New Nitrogen Dioxide Ambient Air Quality Standard Could Pose Challenges
In the more than 200 air quality modeling analyses that ALL4 meteorologists have conducted, demonstrating compliance with the annual nitrogen dioxide (NO2) National Ambient Air Quality Standard (NAAQS) of 53 parts per billion (ppbv) has rarely been an issue. The relative ease for demonstrating compliance with the annual NO2 NAAQS is due to two (2) factors. First, the NAAQS for NO2 is an annual standard and thus any adverse dispersion that could occur based on “worst-case” meteorological conditions in dispersion modeling is averaged over the course of a year, minimizing its effect. Second, U.S. EPA recommends the use of scaling factors to adjust the modeled concentrations of oxides of nitrogen (NOx) to reflect the fact that NOx is converted to NO2 after being emitted from the source. This adjustment results in a reduction of the modeled annual concentrations. U.S. EPA has elected to retain the existing annual NO2 NAAQS of 53 ppbv.
On January 25, 2010, U.S. EPA announced the promulgation of a new 1-hour NAAQS for NO2 of 100 ppbv. ALL4 believes that it will now be more difficult for sources to demonstrate compliance with the NO2 NAAQS using air quality dispersion modeling when required as part of any New Source Review (NSR) air permitting effort. More specifically, a short-term (e.g., 1-hour) standard does not provide the benefit of averaging worst-case dispersion conditions and elevated modeled concentrations (due to a combination of either building aerodynamic downwash or adverse meteorological conditions) over a long period. Based on ALL4’s air quality dispersion modeling experience with sulfur dioxide (SO2) (which already has both long-term and short-term standards), ALL4 has observed that demonstrating compliance with the SO2 NAAQS often hinges on compliance with the short-term (3-hour) standard rather than the annual standard. Based on this experience with SO2, we believe that it will be more difficult for sources to demonstrate compliance with the new 1-hour NO2 NAAQS than with the existing 3-hour SO2 NAAQS due to the extremely low promulgated NO2 NAAQS standard. With the promulgation of the 1-hour NO2 NAAQS, facilities may be well served to perform exploratory air quality modeling analyses to evaluate compliance with the new NO2 NAAQS.
Pennsylvania Proposes to Adopt Effluent Standards for New High TDS Wastewater Discharges
The Pennsylvania Department of Environmental Protection (PADEP) is proposing to amend 25 Pa. Code Chapter 95 (relating to Wastewater Treatment Requirements) to establish new effluent standards for new sources of wastewaters containing high Total Dissolved Solids (TDS) concentrations. The Environmental Quality Board (EQB) published the proposed rulemaking in the November 7, 2009 PA Bulletin (39 Pa.B. 6467), held four (4) public meetings across the State in December 2009, and accepted comments on the amendments through February 5, 2010. The TDS effluent standards would apply to any new “high TDS” wastewater discharge that did not exist on April 1, 2009 as well as any new additional discharge, expanded discharge, or increased discharge from a facility in existence prior to April 1, 2009. A “high TDS” wastewater discharge is considered a TDS concentration that exceeds 2,000 mg/l or a TDS loading that exceeds 100,000 pounds per day. Included in the proposed rulemaking for affected effluents are monthly average discharge limits of 500 mg/l of TDS, 250 mg/l of total chlorides, and 250 mg/l of total sulfates.
Industrial facilities, including surface and underground mining, electric power plants, cement plants, chemical manufacturers, food manufacturers, pharmaceutical manufacturers, iron and steel manufacturers, and other facilities that have existing discharge levels that exceed the proposed limits may be impacted by the proposed regulatory action. As a result of these proposed regulatory amendments, new or increased discharges will be required to install advanced treatment to meet the new TDS, total chloride, and total sulfate effluent requirements. Existing industrial sources of high TDS wastewaters would be able to continue to operate under their existing permit limits and conditions until such time that they propose to expand, increase, or add new wastewater discharges. New or expanded high TDS wastewater sources would not be permitted unless the applicant proposes to install adequate treatment (e.g., reverse osmosis, ultra filtration, or evaporation/crystallization) by January 1, 2011. PADEP anticipates that the cost of advanced treatment to meet the new standards would cost approximately $0.25 per gallon. Industry sources have stated that the mandated level of treatment would require tremendous capital and operating costs, and may create new environmental issues, such as increased energy use, increased air emissions, and additional waste generation in the form of dewatered salts.
In addition to the new limits for new “high TDS” facility wastewater discharges, the proposed rulemaking would also impose limitations from new discharges of wastewater resulting from fracturing, production, field exploration, drilling, or completion of oil and gas wells. These provisions would reportedly provide additional controls and environmental protections to address potential impacts from the development and exploration activity within the Marcellus Shale reserves of the State.
The proposed amendments will go into effect upon publication in the Pennsylvania Bulletin as final-form rulemaking. Facilities with existing wastewater discharges, particularly those with plans to modify, expand, or increase discharges or facilities that accept off-site wastewater for treatment should evaluate the quality of their existing discharge and the potential impact of the proposed new regulatory limits. A copy of the proposed rule can be viewed here.
Air Modeling Dispersion Program Update
The Air and Waste Management Association (AWMA) held a conference entitled Guideline on Air Quality Models: Next Generation of Models in Raleigh, NC from October 28 – 30, 2009. During the conference representatives from U.S. EPA’s Air Quality Modeling Group (AQMG) announced that they would be releasing new versions of AERMOD preprocessors AERMET and AERSURFACE in the not-too-distant future. AERMOD is U.S. EPA’s preferred air dispersion model for evaluating impacts up to 50 kilometers from the source. AERMET is the preprocessor to AERMOD that processes meteorological data for input into AERMOD. Some new features of the updated version of AERMET include the ability to average sub-hourly onsite meteorological data and the use of the station elevation for pressure calculations. In addition, a separate processor to calculate hourly meteorological data from 1-minute Automated Surface Observing System (ASOS) data will be included. AERSURFACE, which is used to calculate micro-meteorological variables from land use patterns, is being updated to allow it to process 2001 National Land Cover Data (NLCD). There also may be the option to incorporate aerial photography data into AERSURFACE for areas in which the 2001 NLCD is not representative of current land use patterns. U.S. EPA also indicated that a release of the AERMOD screening tool AERSCREEN would also be coming soon. AERSCREEN could be used as a screening tool to calculate ambient pollutant concentrations when no meteorological data is available. The screening tool uses a matrix of worst case meteorological conditions in the place of collected meteorological data to calculate ambient concentrations. When released, these updated programs will be available here.
At the same conference, a representative of the National Park Service (NPS) announced that the final 2009 Federal Land Managers Air Quality Related Values Work Group (FLAG) document would be released in the very near future. FLAG is comprised of the NPS, the U.S. Forest Service (USFS), and the U.S. Fish and Wildlife Service (USFWS). The FLAG document outlines procedures to follow when completing an Air Quality Related Values (AQRV) Analysis in Federal Class I air quality areas as part of an air construction permit application. Some key updates contained within the final 2009 FLAG document will be the recommendation to use Method 8 for visibility modeling, the annual average background visibility data instead of 20% best day background visibility, and the 98th percentile values instead of peak predicted values. When the updated FLAG document is released, it will be available here.
Boiler MACT and CISWI Test Data Available On-Line
Last summer, U.S. EPA notified over 100 facilities that they were being called upon to conduct stack testing as part of the Agency’s information gathering efforts to address the vacated National Emissions Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers (Boiler MACT) and the Commercial and Industrial Solid Waste Incinerator (CISWI) rule. 
If your facility was required to conduct testing by U.S. EPA, ALL4 recommends that you visit U.S. EPA’s Boiler MACT and CISWI page to review the data that was submitted for your facility. U.S. EPA’s contractor has consolidated all of the data submitted to date into two (2) databases: one for Boiler MACT sources and one for CISWI sources. The “readme” file associated with the databases indicates that the contractor may have made changes to some of the data that was submitted, based on their review of the data. Because this information will be used in the creation of new Boiler MACT and CISWI emission standards, ALL4 recommends that affected facilities review all of the emissions test results for your facility for accuracy and notify U.S. EPA as necessary if you believe that the data contained in the database is in error.
The GHG Monitoring Plan Due Date is Approaching. Will You Be Ready?
U.S. EPA’s Greenhouse Gas Mandatory Reporting Rule (GHG MMR) codified at 40 CFR Part 98 requires that facilities subject to the rule have a complete written GHG Monitoring Plan by April 1, 2010. At a minimum, a GHG Monitoring Plan must identify:
- The methods used to collect GHG emissions information and supporting data,
- The personnel responsible for collecting the data, and
- The quality assurance, maintenance, and repair methods for all measurement devices used to collect data.
Facilities must maintain their written GHG Monitoring Plan onsite in an electronic or hard-copy format. If requested by U.S. EPA, a facility’s GHG Monitoring Plan must be made available expeditiously for inspection and review.
The GHG MRR is a new rule, currently made up of 30 different subparts that apply to a wide variety of facilities. Developing a GHG Monitoring Plan is the first step of implementation for facilities that are affected by this new rule. This first step involves a thorough analysis of the facility-specific characteristics and operation of combustion units and process units as they relate to the requirements of the GHG MRR. The GHG Monitoring Plan must present how all of the required detailed information about fuels and process parameters is generated, managed, and confirmed.
As with anything so detailed and new, as facilities venture into the GHG MRR for the first time to develop their GHG Monitoring Plans, questions and confusion will ensue. As voluminous as it is, the GHG MRR does not address with certainty how its requirements apply to all of the different ways facilities operate their equipment. In anticipation of, and in response to, questions in this regard from the regulated community, U.S. EPA has endeavored to make available a great deal of support information. Answers to frequently asked questions (FAQs), information sheets, checklists, form templates, technical support documents, and numerous documents explaining responses to comments on the rule as it was proposed are available on U.S. EPA’s website. Unfortunately, the sheer volume of material made available can make it that much harder to find the specific information that individual facilities need to answer their questions. This is all the more reason not to wait until the last minute to develop a required GHG Monitoring Plan.
