Ohio River Valley

A variety of models have been developed to study acid deposition. Sulfuric acid is formed relatively slowly in the atmosphere, so its concentrations are beUeved to be more uniform than o2one, especially in and around cities. Also, the impacts are viewed as more regional in nature. This allows an even coarser hori2ontal resolution, on the order of 80 to 100 km, to be used in acid deposition models. Atmospheric models of acid deposition have been used to determine where reductions in sulfur dioxide emissions would be most effective. Many of the ecosystems that are most sensitive to damage from acid deposition are located in the northeastern United States and southeastern Canada. Early acid deposition models helped to estabUsh that sulfuric acid and its precursors are transported over long distances, eg, from the Ohio River Valley to New England (86—88). Models have also been used to show that sulfuric acid deposition is nearly linear in response to changing levels of emissions of sulfur dioxide (89). 

Altliough ail accurate assessment could not be tnade itnmediately, tlie Ashland spill look a heavy toll on tlie wildlife of the Ohio River Valley. More tluiii 5000 waterfowl were killed when their feathers became contaminated witli oil. Birds tliat e. perience oil conlaminalion lose tlieir natural insulation and buoyancy and cither drown or freeze to death. In addition, a massive fish kill was e. pectcd in the spring when the ri cr entered a new cycle. 

Ohio River Valley Sanitation Commission. 1980. Assessment of water quality eonditions. Ohio River Mainstream 1978-9. Cincinnati, OH Ohio River Valley Water Sanit Comm 34 T-53. 

Gersch, H. K., Robertson, J. D., Henderson, A. G., Pollack, D., and Munson, C. A. (1998). PIXE analysis of prehistoric and protohistoric Caborn-Welbom phase copper artifacts from the lower Ohio River Valley. Journal of Radioanalytical and Nuclear Chemistry 234 85-90. 

Ohio River Valley Water Sanitation Commission. 1982. Assessment of the Water Quality Conditions Ohio River Mainstream 1980-81. Ohio River Valley Water Sanit. Comm., Cincinnati, OH. 

Current reviews of surface water monitoring data in the peer reviewed literature are lacking. The highest concentrations observed in surface waters of the United States sampled before 1984 were 394 and 120 ppb. These concentrations were observed in rivers in highly industrialized cities (Ewing et al. 1977 Pellizzari et al. 1979). Typical concentrations for most sites that are not heavily industrialized appear to range from trace levels to 22 ppb (Ohio River Valley Sanitation Commission 1980, 1982). Data from EPA s STORET database indicate that chloroform was detected in 64% of 11,928 surface water sample data points at a median concentration of 0.30 ppb (Staples et al. 1985). 

Filters have also been analyzed from sites in the vicinity of a Lurgi coal gasifier (16) and in the Ohio River Valley. Both these results and the NASN results will be discussed in detail elsewhere. 

The ratio of elemental (EC) to organic carbon (OC) has been measured in many studies and is commonly found to be less than one. For example, Shah et al. (1986) measured EC and OC in particles from both urban and rural areas across the United States and found the urban average concentrations to be 6.6 /xg m 3 for OC and 3.8 gg m 3 for EC, i.e., a ratio of EC OC of 0.6. Similarly, in the Los Angeles area, EC typically represents about a third of the carbonaceous component of particles (Rogge et al., 1993d). For rural areas, the concentrations were about a third of those in the urban areas, but the ratio was about the same, at 0.5, consistent with ratios of 0.4-0.5 measured in the Ohio River Valley by Huntzicker et al. (1986). Novakov et al. (1997) measured carbonaceous aerosol off the east coast of the United States at altitudes from 0.2 to 3.0 km and report that the ratio of EC OC is 0.1. 

Cusick, A.W., Polygonum perfoliatum, new record Polygonaceae, a dangerous new weed in the Ohio River Valley, USA, Ohio J. Sci., 86, 3, 1984. 

Ohio River Valley Water Sanitation Commission. 1979. Water treatment process modifications for trihalomethane control and organic substances in the Ohio River. Cincinnati, OH Ohio River Valley Water Sanitation Commission. 

Baker, G. Clarke, P. Gerstle, R. Mason, W. Phillips, M., "Emission Characteristics of Major Fossil Fuel Power Plants in the Ohio River Valley," Knapp, K. T., Project Officer EPA Contract No. 68-02-3271, U. S. Environmental Protection Agency, Research Triangle Park, NC, 1984. 

One afternoon in June 1988, in an Ohio River Valley plant a similar incident occurred. Regrettably, three employees received relatively minor burns, abrasions, and lacerations during a fire and an overpressurization of a tank containing about a 3-ft. (1 m) level of a combustible liquid. At the time of the incident, a welder was repairing a moderate-sized vessel—25 ft. (7.6 m) high and 20 ft. in diameter (6.1 m). 

In my view, hybrid receptor models are the most likely approach for provide reasonable answers to the sulfate deposition problem within a time that they might be of use in influencing controls that may be imposed on S02 and NO sources. This does not mean that there is no need for further field studies. The Allegheny Mt. and Deep Creek Lake data sets were taken so close together that one would feel much safer if similar data were available at several other sites, e.g., the three sites of the Ohio River Valley study (20) and one or two sites to the northeast of Allegheny Mt.,... 

Figure 7. Variation in year-to-year trajectory calculations beginning from the upper Ohio River Valley. The curves represent the coefficient of variation in the distributions of annual "natural potential" of material released in the upper Ohio River Valley reaching locations downwind from this source area.

Gordon and Olmez (4) have used Equation 3 to model sulfate resulting from a multiple source distribution of coal-burning emissions, such as in the Ohio River Valley. Their results are quantitatively consistent with measured aerosol S/Se ratios of about 1700 and 3000, within and downwind of this region. 

Trace Element Concentrations on Fine Particles in the Ohio River Valley... 

Trace element compositions of airborne particles are important for determining sources and behavior of regional aerosol, as emissions from major sources are characterized by their elemental composition patterns. We have investigated airborne trace elements in a complex regional environment through application of receptor models. A subset (200) of fine fraction samples collected by Shaw and Paur (1,2) in the Ohio River Valley (ORV) and analyzed by x-ray fluorescence (XRF) were re-analyzed by instrumental neutron activation analysis (INAA). The combined data set, XRF plus INAA, was subjected to receptor-model interpretations, including chemical mass balances (CMBs) and factor analysis (FA). Back trajectories of air masses were calculated for each sampling period and used with XRF data to select samples to be analyzed by INAA. 

Figure. 1. Map of Ohio River Valley showing ORV sites and coal-fired power plants, with sizes of circles indicating plant capacities. West, Center and East sampling sites indicated as W, C and E, respectively.

To examine the first problem in more detail, Gordon and Olmez performed calculations that crudely simulated an air mass moving up the Ohio River Valley and into New England (14). They assumed that identical coal-fired plants were spaced at 50-km intervals over 1000 km and eliminated them for an additional 800 km. They assumed a ratio of Se/S = 0.00028 in the coal, and that 50% of the Se is released up the stack, of which 50% quickly becomes attached to particles, with the remainder staying in the gas phase. The atmosphere was assumed to be uniformly mixed up to 1.5 km and the wind speed, 10 km/hr. Selenium and sulfate particles were assumed to have the same deposition velocity, Vg2 and SO2 a larger value, Vg. Sulfur dioxide was also converted at a rate kr —... 

We have performed more detailed hybrid-receptor calculations in an attempt to fit Shaw and Paur s gas-phase and particulate S data for three stations in the Ohio River Valley (1). Surprisingly,... 

Figure. 2. Hybrid receptor model predictions of concentrations of SO2, SO4, particulate Se and the S/Se ratio from Texas up through the Ohio River Valley. Experimental data from XRF studies of Shaw and Paur (1) for southwest back-trajectories are connected by dashed lines.

This increased the sulfate levels rather uniformly, but did not change the slope vs. distance up the Valley appreciably. The difficulty is that there are very few SO2 sources to the southwest of the west site closer than Texas. Possibly the observations could be fitted by including a more specific treatment of wet deposition. The lower frequency of rainfall in Texas relative to the Ohio River Valley may allow sulfur to survive transport from Texas to Kentucky more easily than transport up the Valley. Calculations using another type of hybrid model, that of Samson et al. (23,24), which can explicitly handle the removal by precipitation, might be the most successful approach to understanding these data. Because of their unique and comprehensive nature, these data are some of the most important to be fitted by models. No model should be considered reliable unless it can do so ... 

Considerable progress is being made in the development of regional scale receptor modeling. There is surprisingly little variation of relative elemental concentration patterns of fine particles associated with various back-trajectory groups in the Ohio River Valley. 

Using both a hybrid receptor model, developed by Lewis and Stevens ( 2) and modified by Gordon and Olmez (3), and a simple model of emission from the Ohio River Valley, we compare the results of the College Park (CP) samples as well as those of another continuous set of samples taken from July 3-29, 1983 at Wallops Island, VA (WI), to predicted results. Single-source differential equations (2) are used to describe the time-varying concentrations of SO2, SO and a particulate element characteristic of coal-fired power plant emissions (chosen here as Se). An additional equation (3) can be added to describe the concentration variation of B(0H)3 The following rate constants apply to the concentrations of the four species in question ... 

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