Progress 10/01/03 to 09/30/09

Outputs
OUTPUTS: This project has supported long-term monitoring of precipitation chemistry at site PA42 (Leading Ridge, located in Stone Valley, amidst the Penn State Forest), providing information on the status and trends of multiple chemical elements that are deposited to the landscape via precipitation. The data from this site and from others in the network support informed decisions on air quality issues related to precipitation chemistry, and are a key component of understanding of how air quality, in turn, affects forested ecosytems and water quality. Analysis of long-term data from PA42 indicates that a significant decrease in precipitation acidity has been observed along with concurrent decreases in sulfate and nitrate concentrations. Changes in precipitation chemistry at this site are directly related to observed reductions in SO2 and NOx emissions in western PA and portions of the Ohio River Valley. Despite the obvious success of Title IV, the pH and sulfate and nitrate concentrations in precipitation in the state continue to be higher than nearly every other NADP/NTN site in North America. Nitrate and ammonium concentration data from this and other NADP/NTN sites throughout the Mid-Atlantic region were used refine daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay watershed that are used to assess the importance of nitrogen deposition to the eutrophication of the Bay. Data from this project are freely available to the public on the Internet at two locations: 1) http://nadp.sws.uiuc.edu/; and 2) http://www.dep.state.pa.us/dep/DEPUTATE/airwaste/aq/acidrain/acidrain .htm. PARTICIPANTS: Dr. Elizabeth Boyer: Principal investigator, Associate Professor, School of Forest Resources (SFR), and Assistant Director, Penn State Institutes of Energy and the Environment (PSIEE). Dr. James Lynch: Key collaborator, Professor Emeritus, SFR. Mr. Jeffrey Grimm: Research Assistant, PSIEE Mr. Kevin Horner: Research Technician, PSIEE Mr. Matt Borden: Research Technician, PSIEE TARGET AUDIENCES: State Regulatory Agencies (Dept. of Environmental Protection) Federal Regulatory Agencies (U.S. Environmental Protection Agency, USGS) State and Federal Research Institutions Academic Institutions (Colleges and Universities) National Atmospheric Deposition Program PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Data from this monitoring program have provided a basis for assessing the effectiveness of the Clean Air Act Amendments of 1990 in reducing acidic deposition in PA. The results from this project provided a means for assessing the relative importance of atmospheric deposition as a non-point source of pollutants (e.g., nitrogen species) contributing to the acidification of and recovery of acidified surface waters through the PA and, importantly, the larger northeastern region. The work also contributed to an understanding of the sources of pollutants that are transported long-range in the atmosphere to this rural monitoring site. Further, the project has contributed to an understanding of the role of atmospheric deposition on eutrophication of coastal watersheds in the Chesapeake Bay and the mid-Atlantic region.

Publications

• Elliott, E.M., C. Kendall, S.D. Wankel, D.A. Burns, E.W. Boyer, K. Harlin, D.J. Bain, and T.J. Butler. 2007. Nitrogen isotopes as indicators of NOx source contributions to atmospheric nitrate deposition across the Midwestern and Northeastern United States. Environmental Science & Technology 41(22):7661 -7667. http://dx.doi.org/10.1021/es070898t.
• Golden, H.E., E.W. Boyer, M.G. Brown, E.M. Elliott, and D.K. Lee. 2008. Simple approaches for measuring dry atmospheric nitrogen deposition inputs to watersheds. Water Resources Research 44. http://dx.doi.org/10.1029/2008WR006952.
• Sebestyen, S.D., J.B. Shanley, and E.W. Boyer. 2009. Documenting effects of atmospheric pollutants on stream chemistry using high-frequency sampling. R. T. Webb and D. J. Seemens (Eds.). USGS Scientific Investigations Report 2009-5049. Planning for an Uncertain FutureMonitoring, Integration, and Adaption: Proceedings of the Third Interagency Conference on Research in the Watersheds. pp. 171-175.
• Boyer, E.W., J.A. Lynch, J.W. Grimm, and K.S. Horner. 2009. Atmospheric deposition: spatial and temporal variations in Pennsylvania 2007-2008. Report prepared for Pennsylvania Department of Environmental Protection. 248 pp.

Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: Long-term trends in precipitation at the Leading Ridge site shows a significant decline in SO2 and NOx deposition, which in turn is correlated with an overall increase in the pH of rainwater. For instance, the 2006 statewide mean annual pH (4.46) was the same as in 2005 and the highest pH (lowest acidity) measured in Pennsylvania since monitoring began in 1981. The hydrogen ion concentration (measured as pH) of precipitation in Pennsylvania has declined approximately 51% (40.0 ueq/L) over the last 24 years. The decline in "acid rain" has been attributed to reductions in sulfur dioxide and nitrogen oxides emissions and to a much lesser extent increasing base cation and ammonium concentrations in some regions of the state. Sulfate concentrations have decreased approximately 39% (25.1 ueq/L) since 1983. The statewide mean annual sulfate concentration in 2006 was 2.034 mg/L. Mean annual sulfate concentrations in 2006 were higher than in 2005 and generally higher than any year since 2002. Last, nitrate concentrations have decreased approximately 34% (11.7 ueq/L) since 1983. The statewide mean annual nitrate concentration in 2006 was 1.274 mg/L; this was the second lowest (by 0.001 mg/L) mean concentration recorded the past 24 years. The measured reductions in nitrate concentrations and wet depositions can be attributed to reductions in nitrogen oxides emissions in Pennsylvania and in upwind states. Nitrogen data from this project and other NADP/NTN sites throughout the Mid-Atlantic region are being used refine N-loading models for the Chesapeake Bay watershed, that have underscored the primary importance of nitrogen deposition to the eutrophication of the Bay. Moreover, reductions in deposition of the acid anion to the LREW seem to have resulted in measurable decreases in sulfate concentrations in stream water draining these watersheds and a concurrent decrease in stream acidity. Data from this project are available on the Internet at: http://nadp.sws.uiuc.edu and http://www.dep.state.pa.us. Finally, a three-year project was recently funded that will extend (and expand) the breadth of this research on the Leading Ridge project into 2010. Dr. Elizabeth Boyer has assumed lead PI status on the project starting and will oversee the new project. She and Dr. Carrick will collaborate with the other personnel to publish (primary, refereed journals) results from the atmospheric monitoring data from the previous project. PARTICIPANTS: Dr. Hunter Carrick: PI; Associate Professor, School of Forest Resources, Penn State University Dr. Elizabeth Boyer: co-PI; Assocaite Professor, School of Forest Resources, Penn State University Dr. James Lynch: co-PI; Professor Emeritus; School of Forest Resources, Penn State University Dr. Caleb Tzilkowski: Post-doctoral Fellow; School of Forest Resources, Penn State University Mr. Jeffrey Grimm: Research Assistant; School of Forest Resources, Penn State University Mr. Kevin Horner: Research Technician III; School of Forest Resources, Penn State University TARGET AUDIENCES: State Regulatory Agencies (Dept. of Environmental Protection) Federal Regulatory Agencies (U.S. Environmental Protection Agency) State and Federal Research Institutions Academic Institutions (Colleges and Universities) PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Data from this monitoring program provide a basis for assessing the effectiveness of the Clean Air Act Amendments of 1990 in reducing acidic deposition in PA. The results from this project also provide a means for assessing the relative importance of atmospheric nitrogen deposition (both NH4 and NO3) as a non-point source of nitrogen contributing to the eutrophication of the Chesapeake Bay and other coastal areas and the recovery of acidified surface waters through the PA and the Mid-Atlantic region. Eventually, the project will provide information on the consequences specific atmospheric contaminants have on healthy and sustainability of key aquatic organisms (amphibians, fish, and human health).

Publications

• Lynch, J.A., K.S. Horner, J.W. Grimm, H.J. Carrick, and E. Boyer. 2007. Mercury deposition in Pennsylvania: 2006 status report. Technical Report, Department of Environmental Protection. 108 p.
• Lynch, J.A., K.S. Horner, J.W. Grimm, E. Boyer, and H.J. Carrick. 2007. Reductions in acidic wet deposition in Pennsylvania following implementation of the clean air act amendments of 1990 1995-2006. Technical Report, Department of Environmental Protection. 46 p.
• Lynch, J.A., K.S. Horner, J.W. Grimm, and H.J. Carrick. 2006. Atmospheric deposition: Spatial and temporal variation in Pennsylvania. Technical Report, Department of Environmental Protection. 83 p.
• Lynch, J.A., H.J. Carrick, K.S. Horner, and J.W. Grimm. 2005. Reductions in acidic wet deposition following implementations of the clean air act amendments of 1990: 1995-2004. Technical Report, Department of Environmental Protection. 43 p.
• Lynch, J.A., H.J. Carrick, K.S. Horner, and J.W. Grimm. 2005. Mercury Deposition in Pennsylvania: 2005 Status report. Technical Report, Department of Environmental Protection. 114 p.

Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Analysis of data from PA42 indicates that a significant decrease in precipitation acidity (28.5 /L,40.4%) has been observed along with concurrent decreases in sulfate (21.6 /L, 35.1%) and nitrate (8.5 /L, 26.0%) concentrations. Changes in precipitation chemistry at this site are directly related to observed reductions in SO2 and NOx emissions in western PA and portions of the Ohio River Valley. In 2005, the mean annual, growing, and dormant season pH of precipitation (all 4.44) were the second highest values recorded since monitoring began at PA42 in 1979. Despite the obvious success of Title IV, the pH and sulfate and nitrate concentrations in precipitation in the state continue to be higher than nearly every other NADP/NTN site in North America. Nitrate and ammonium concentration data from this and other NADP/NTN sites throughout the Mid-Atlantic region were used refine daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay watershed that are used to assess the importance of nitrogen deposition to the eutrophication of the Bay. Concurrent with reductions in sulfate and nitrate concentrations there has been similar reductions in wet deposition. Reductions in deposition of the acid anion to the LREW have resulted in measurable decreases in sulfate concentrations in stream water draining these watersheds and a concurrent decrease in stream acidity. Atmospheric deposition monitoring will continue at this site through 2007. Data from this project are available on the Internet at: http://nadp.sws.uiuc.edu and http://www.dep.state.pa.us. Our plan for the up-coming year is to expand the breadth of research on the Leading Ridge project, by developing an experimental research component that compliments the excellent monitoring database. First, the additional new personnel on the project have expanded the expertise regarding how environmental contaminant effect the structure and function of aquatic ecosystems (Dr. Carrick, PI). Second, Dr. Caleb Tzilkowski (post-doctoral fellow) completed his work on the project, that resulted in one published abstract, a publication in preparation, and a final report to the PA-DEP. Both of these documents will be submitted in June 2008. Last, Dr. Elizabeth Boyer will assume lead PI status on the project starting in 2008. She and Dr. Carrick will collaborate with the other personnel to publish (primary, refereed journals) results from the atmospheric monitoring data. Number of graduate students. 1 PARTICIPANTS: Dr. Hunter Carrick, PI, Associate Professor, School of Forest Resources, Penn State University; Dr. James Lynch, co-PI, Professor Emeritus, School of Forest Resources, Penn State University; Dr. Caleb Tzilkowski, Post-doctoral Fellow, School of Forest Resources, Penn State University; Mr. Jeffrey Grimm, Research Assistant, School of Forest Resources, Penn State University; and Mr. Kevin Horner, Research Technician III, School of Forest Resources, Penn State University. TARGET AUDIENCES: State Regulatory Agencies (Dept. of Environmental Protection); Federal Regulatory Agencies (U.S. Environmental Protection Agency); and State and Federal Research Institutions Academic Institutions (Colleges and Universities).

Impacts
Data from this monitoring program provide a basis for assessing the effectiveness of the Clean Air Act Amendments of 1990 in reducing acidic deposition in PA. The results from this project also provide a means for assessing the relative importance of atmospheric nitrogen deposition (both NH4 and NO3) as a non-point source of nitrogen contributing to the eutrophication of the Chesapeake Bay and other coastal areas and the recovery of acidified surface waters through the PA and the Mid-Atlantic region. Eventually, the project will provide information on the consequences specific atmospheric contaminants have on healthy and sustainability of key aquatic organisms (amphibians, fish, and human health).

Publications

• National Atmospheric Deposition Program/National Trends Network. 2007. NADP/NTN Annual Data Summary, 2006. Precipitation Chemistry in the United States: Annual Report. Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820. 16 pp.
• Tzilkowski, C.J., J.A. Lynch, K.S. Horner, and H.J. Carrick. 2007. Atmospheric deposition of trace metals at Presque Isle, Pennsylvania. 50th Annual Conference on Great Lakes Research. International Association for Great Lakes Research, Univesity Park, PA. p. 200 (Abstract).

Progress 01/01/06 to 12/31/06

Outputs
The aim of this project is to collect long-term atmospheric deposition data at one site (PA42) on the Leading Ridge Experimental Watersheds in northern Huntingdon County. Leading Ridge is one of nearly 250 such sites throughout the USA that comprise the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Participation in this program is authorized under National Research Support Project Number 3 (NRSP-3). The project is important because the effectiveness of the Clean Air Act Amendments of 1990 (Title IV) is evaluated from the data collected at PA42 and other sites throughout the Eastern USA. Results are used to set limits and requirements for atmospheric emissions discharged by electric utilities in an effort to reduce sulfur dioxide (SO2), nitrogen oxides emissions (NOx), and ultimate acidic deposition across the region. Analysis of data from PA42 indicates a significant decrease in precipitation acidity (28.5 ueq/L,40.4%) has been observed along with concurrent decreases in sulfate (21.6 ueq/L, 35.1%) and nitrate (8.5 ueq/L, 26.0%) concentrations. Changes in precipitation chemistry at this site are directly related to observed reductions in SO2 and NOx emissions in western PA and portions of the Ohio River Valley. In 2005 the mean annual, growing and dormant season pH of precipitation (all 4.44) were the second highest values recorded since monitoring began at PA42 in 1979. Despite the obvious success of Title IV, the pH and sulfate and nitrate concentrations in precipitation in the state continue to be higher than nearly every other NADP/NTN site in North America. Nitrate and ammonium concentration data from this and other NADP/NTN sites throughout the Mid-Atlantic region were used to refine daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay watershed used to assess the importance of nitrogen deposition to the eutrophication of the Bay. Concurrent with reductions in sulfate and nitrate concentrations there has been similar reductions in wet deposition. Reductions in deposition of the acid anion to the LREW have resulted in measurable decreases in sulfate concentrations in stream water draining these watersheds and a concurrent decrease in stream acidity. Atmospheric deposition monitoring will continue at this site through 2006. Data from this project are available at: http://nadp.sws.uiuc.edu and http://www.dep.state.pa.us. Our plan for the up-coming year is to expand the breadth of research on the Leading Ridge project by developing an experimental research component that compliments the excellent monitoring database. First, additional personnel are now working on the project that have expertise regarding how environmental contaminant effect the structure and function of aquatic ecosystems (Dr. Carrick, PI and Dr. C. Tzilkowski, post-doctoral fellow). Experiments are planned that will test the effects common atmospheric contaminant such as NOx and heavy metals (e.g., mercury) have on the stream and pond ecosystems (biodiversity, and productivity). Second, Dr. Carrick will collaborate with other personnel to publish some of the results from the atmospheric monitoring data.

Impacts
Data from this monitoring program provide a basis for assessing the effectiveness of the Clean Air Act Amendments of 1990 in reducing acidic deposition in PA. The results from this project also provide a means for assessing the relative importance of atmospheric nitrogen deposition (both NH4 and NO3) as a non-point source of nitrogen contributing to the eutrophication of the Chesapeake Bay and other coastal areas and the recovery of acidified surface waters through the PA and the Mid-Atlantic region. Eventually, the project will provide information on the consequences specific atmospheric contaminants have on healthy and sustainability of key aquatic organisms.

Publications

• Lynch, J.A. 2006. National Atmospheric Deposition Program/National Trends Network. NADP/NTN Annual Data Summary, 2005. Precipitation Chemistry in the United States: Annual Report. Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820. 16 pp.

Progress 01/01/05 to 12/31/05

Outputs
This project maintains long-term support for an atmospheric deposition monitoring site (PA42) on the Leading Ridge Experimental Watersheds (LREW) in northern Huntingdon County. This is one of approximately 200 such sites throughout the USA that comprise the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Participation in this program is authorized under National Research Support Project Number 3 (NRSP-3). Data collected at PA42 and other sites throughout the Eastern USA have been used to evaluate the effectiveness of the Clean Air Act Amendments of 1990, Title IV which required electric utilities to reduce sulfur dioxide (SO2) and nitrogen oxides emissions (NOx) in order to reduce acidic deposition in the region. Analysis of data from PA42 indicates that a significant decrease in precipitation acidity of 26.4 ueq/L (37.8%) has been observed along with concurrent decreases in sulfate (20.1 ueq/L, 32.8%) and nitrate (6.9 ueq/L, 21.4%) concentrations. Changes in precipitation chemistry at this site are directly related to observed reductions in SO2 and NOx emissions in western PA and the Ohio River Valley. In 2004, the mean annual, growing, and dormant season pH of precipitation (all 4.44) were the second highest values recorded since monitoring began at PA42 in 1979, and the first time there were no seasonal differences. Despite the obvious success of Title IV, the pH and sulfate and nitrate concentrations in precipitation in the state continue to be higher than nearly every other NADP/NTN site in North America. Nitrate and ammonium concentration data from this and other NADP/NTN sites throughout the Mid-Atlantic region were used to develop daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay watershed. These models are used to assess the importance of nitrogen deposition to the eutrophication of the Bay. Concurrent with reductions in sulfate and nitrate concentrations there has been similar reductions in wet deposition. Reductions in deposition of these acid anion to the LREW have resulted in measurable decreases in sulfate concentrations in stream water draining these watersheds and a concurrent decrease in stream acidity. Atmospheric deposition monitoring will continue at this site through 2006. Data from this project are available on the Internet at: http://nadp.sws.uiuc.edu and http://www.dep.state.pa.us.

Impacts
This research provides a basis for assessing the effectiveness of the Clean Air Act Amendments of 1990 in reducing acidic deposition in PA. The results from this project also provide a basis for assessing the relative importance of atmospheric nitrogen deposition (both NH4 and NO3) as a non-point source of nitrogen contributing to the eutrophication of the Chesapeake Bay and other coastal and to the recovery of acidified surface waters through the PA and the Mid-Atlantic Region.

Publications

• Lynch, J.A., Horner, K.S. and Grimm, J.W. 2005. Atmospheric deposition: Spatial and temporal variations in Pennsylvania, 2004. Annual technical report to the PA Dept. of Environ. Protection, University Park, PA 179 pp.
• National Atmospheric Deposition Program/National Trends Network. 2005. NADP/NTN Annual Data Summary, 2004. Precipitation Chemistry in the United States: Annual Report. Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820. 16 pp.
• Grimm, J.W. and Lynch, J.A. 2005. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay watershed. Environmental Pollution, 135(3):445-455.
• Lynch, J.A. and Kerchner, M. 2005. The National Atmospheric Deposition Program: 25 years of monitoring in support of science and policy and an ammonium workshop: State of science and future needs. Environmental Pollution, 135(3):343-346.

Progress 01/01/04 to 12/31/04

Outputs
Based on data from the National Atmospheric Deposition Program (NADP), acidic deposition over much of the Northeast and Mid-Atlantic regions of the USA has decreased the past 25 years, especially since implementation in 1995 of the Clean Air Act Amendments of 1990, Title IV, which required electric utilities to reduce sulfur dioxide (SO2) and nitrogen oxides emissions (NOx), the major precursors of acidic deposition in the region. This was also the case at the Leading Ridge NADP site (PA42) in northern Huntingdon County PA, where a statistically significant decrease in precipitation acidity of 25.0 micro eq/L (35.9%) has been observed along with concurrent decreases in sulfate (18.4 micro eq/L 30.3%) and nitrate (5.2 micro eq/L, 16.5%) concentrations. A non significant increase in ammonium (NH4) concentrations has also contributed to the decrease in precipitation acidity at the site. Increasing NH4 concentrations have been attributed to increased ammonia emissions from intensive agriculture activities throughout much of the Mid-Atlantic region. In 2003, the mean annual (4.43), growing (4.37) and dormant (4.55) season pH of precipitation were the highest record since monitoring began at the Leading Ridge site in 1979. Although sulfate concentrations in 2003 were within the range of values observes the past 25 years, the growing season mean was more than 1.5 mg/L lower than prior to implementation of the CAAA. Annual and seasonal nitrate concentrations, however, were the lowest reported to date averaging around 1.35 mg/L. Concurrent with the reduction in concentrations have been similar reductions in wet deposition of both sulfate and nitrate acid anions. The long-term concentration and deposition trends at PA42 are consistent with reported trends at most other NADP sites in the region. Despite the obvious success of the emissions reduction programs to reduce acid deposition in PA, the pH of precipitation in the Commonwealth and sulfate and nitrate concentrations and wet deposition continue to be higher than nearly every other NADP site in North America. Atmospheric deposition monitoring will continue at this site through 2004. Data from this project are available on the Internet at: http://nadp.sws.uiuc.edu and http://www.dep.state.pa.us.

Impacts
This research provides a basis for determining whether the Clean Air Act Amendments of 1990 have been successful in reducing acidic deposition in PA. The results from this project also provide a basis for assessing the relative importance of atmospheric nitrogen deposition (both NH4 and NO3) as a non-point source of nitrogen contributing to the eutrophication of the Chesapeake Bay and other coastal waters along the Mid Atlantic.

Publications

• Lynch, J.A., Horner, K.S. and Grimm, J.W. 2004. Atmospheric deposition: Spatial and temporal variations in Pennsylvania, 2003. Annual technical report to the PA Dept. of Environ. Protection, PSIE2004-1, University Park, PA 179 pp.
• National Atmospheric Deposition Program/National Trends Network. 2004. NADP/NTN Annual Data Summary, 2003. Precipitation Chemistry in the United States: Annual Report. Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820. 16 pp.
• Grimm, J.W. and Lynch, J.A. 2004. Enhanced wet deposition estimates using modeled precipitation inputs. Environmental Monitoring and Assessment, 90/1-3:243-268.