REVIEW OF AVAILABLE MODELS TO CALCULATE ACID DEPOSITION SEE Note 22. The U.S. Environmental Protection Agency intends to solicit and negotiate with one firm, the Atmospheric Environmental Research, Inc. 2682 Bishop Drive, Suite 120 San Ramon, CA 94583. The Statement of Work for this Sole Source procurement is listed below. Any firm that believes they can complete the work described should contact the EPA in writing providing a capability statement (not company brochures/pamphlets)no later than 9:00 AM local time on Monday, March 22, 1999. Statements may be mailed to US EPA Attn: Mekeba Brown; 401 M Street, SW (3803R); Washington, DC 20460 or E:Mailed to brown.mekeba@epa.gov. Telephone Inquires will not be accepted. STATEMENT OF WORK I. Schedule and Level of Effort Duration: 12 Months from time of execution Hours: II. Background Congress passed the Clean Air Act Amendments in 1990 (CAAA). Title IV of this legislation called for a ten million ton reduction of S02 and a two million ton reduction in NOX entering the atmosphere from electric utility sources relative to 1980 emissions. The Acid Rain Division ARD), within the Environmental Protection Agency (EPA), has been responsible for implementing Title IV of the CAAA. Congress called for a regulatory program to be established, for assessment to occur and progress toward environmental goals to be evaluated and reported. In addition, new control strategies are being suggested for the same sources affected by Title IV and Congress has asked ARD to provide analysis results. ARD needs to model air concentration and to predict deposition of relevant chemical species to answer these mandates. ARD requires a sound scientific basis be used to decide which models to use. The last reasonably comprehensive review of acid deposition modeling was performed by the National Acid Precipitation Assessment Program (NAPAP) and published in 1990. ARD needs an up-to-date review of models capable of predicting deposition and air concentrations of relevant chemical species. This work will provide this needed information. III. Statement of Work ARD needs a report that reviews the current state of the science of numerical modeling of Acid Deposition and related processes. The contractor shall provide a critical review of relevant models as identified and listed here: *Models-3 (CMAQ), supported by the US EPA office of Research and Development (ORD) and applied to North America (NA). *RADM/RPM, supported by US EPA ORD applied to Eastern US *DAQM2 (a recent version of MAQSIP by MCNC) supported by the Denver Regional Air Quality Council applied to NA. *ADOM, supported by Environment Canada applied to Eastern NA. *URM, supported by Southern Appalachian Mountain Initiative applied to Eastern United States (US). *STATMOD supported by EPRI applied to NA *ASTRAP supported by DOE Argonne National Labs applied to NA. *REMSAD supported by EPA OAQPS applied to NA. If resources permit the review shall include the following additional models and a discussion of the application of these models to problems on the NA continent: *STEM-III, supported by University of Iowa applied primarily to Asia *TADAP, supported by the German Umweltbundesamt applied to Western Europe Finally, a brief discussion of reduced form models shall be included as a result of consultation with the Project Manager if resources permit. The reduced form models to be discussed are: *RAINS, developed by IIASA applied to Asia (see http://www.iiasa.ac.at/~heyes/docs/rains.asia.html) *TAF, developed by many applied to US (transport is a reduced form of ASTRAP. See http://www.lumina.com/taf). For each model the contractor shall review the model formulation for simulating emissions (including treatment of plume rise), advective and convective transport, turbulent diffusion, gasphase and aqueous-phase chemistry, aerosol formation, cloud parameterization, dry deposition, and wet deposition. In the event a model is coupled to a specific meteorological model the contractor shall provide a brief description of the meteorological model with proper references for model description, applicationand evaluation. Previous applications to calculate deposition and air concentration of relevant chemical species shall be summarized for each model. This summary shall include an indication of whether the study was published and whether the publication was peer reviewed. For each model the contractor shall identify the strengths and weakness in the model formulations and provide recommendations for correction of weaknesses. In addition, the boundary of problems to which a given model either should or should not be applied shall be provided. Specifically, comment shall be addressed to problems regarding the North American Continent. In commenting on problem applicability the contractor shall document computational requirements and resource considerations for applying the model to appropriate problems on the NA Continent. Finally, the contractor shall take into account and comment on the model formulation, previous model performances, and model ease of use. IV. Deliverables and Schedule Progress Report Quarterly (once every three months) from time of execution Draft Report Six months from time of execution Final Report One month from receipt of final EPA comments on Draft Supporting Documentation Delivered with Final Report E-MAIL: Click Here to Contact the Contract Specialist, brown.mekeba@epa.gov. Posted 03/08/99 (W-SN305859).

Loren Data Corp. http://www.ld.com (SYN# 0518 19990310\SP-0010.MSC)