Glen A. Marotz

Performance evaluation of the portable MiniVOL particulate matter sampler

Abstract The MiniVOL sampler is a popular choice for use in air quality assessments because it is portable and inexpensive relative to fixed site monitors. However, little data exist on the performance characteristics of the sampler. The reliability, precision, and comparability of the portable MiniVOL PM10 and PM2.5 sampler under typical ambient conditions are described in this paper. Results indicate that the MiniVOL (a) operated reliably and (b) yielded statistically similar concentration measurements when co-located with another MiniVOL (r2=0.96 for PM10 measurements and r2=0.95 for PM2.5 measurements). Thus, the characterization of spatial distributions of PM10 and PM2.5 mass concentrations with the MiniVOL can be accomplished with a high level of confidence. The MiniVOL also produced statistically comparable results when co-located with a Dichotomous Sampler (r2=0.83 for PM10 measurements and r2=0.85 for PM2.5 measurements) and a continuous mass sampling system (r2=0.90 for PM10 measurements). Environmental factors such as ambient concentration, wind speed, temperature, and humidity may influence the relative measurement comparability between these sampling systems.

An approach to examining regional atmosphere plant interactions with phenological data

Matching plant and climatic distributional patterns at a variety of scales is a common geographical exercise, and is directed toward determination of the gross structure of plant-climate interactions. Usage of plant phenological data provides another means of examining such interactions. A 20-year record from an eastern North American phenological network is used to illustrate a regional scale approach to the subject. A simple model incorporating surface, upper air, and first leaf emergence data is described and tested. Results show that a small percentage of synoptic events, marked by warm air advection, account for the majority of high energy accumulation totals. The event model is as good as standard accumulation models for predicting the arrival of the spring green

Effects of variations in recharge on groundwater quality

Abstract The predominant regional effect of recharge on municipal groundwater quality in Kansas is the dilution of mineralized water in aquifers with relatively shallow water tables. The individual dissolved constituents contributing most to the water-quality variations are sulfate and chloride, and the calcium and sodium accompanying them, which are derived from the dissolution of evaporite minerals within the aquifer or from saline formation water in bedrock underlying the aquifer. The relationship between recharge and groundwater-quality variation can be quantified by associating certain climatic indices, especially the Palmer Drought Index, with quality observations. The response time of the maximum water-quality change relative to the occurrence of drought or substantial recharge ranges from a month to 3 years depending on the aquifer characteristics, and is generally proportional to the saturated thickness and specific yield. The response time is also affected by discharge to and recharge from nearby streams and by the well construction, particularly the placement of the screened interval, and pumping stress.

Application of a Risk Assessment Based Approach to Designing Ambient Air Quality Monitoring Networks for Evaluating Non-Cancer Health Impacts

An ambient air quality monitoring network has been establishedusing risk assessment techniques to evaluate adverse health effects from exposures to airborne contaminants. The risk assessment method was compared to traditional methods of establishing air quality monitoring networks: identifying maximumconcentration impacts or maximum total population. Results suggest that the health risk method best predicted the locationof adverse, non-carcinogenic respiratory illnesses during the evaluation period. Spearman Rank Correlation Coefficient, rs, values obtained using the risk assessment method werestatistically greater than the values obtained using theconcentration and population methods. The concentration methodwas the least accurate predictor of adverse effects.

A Method of Predicting Point and Path- Averaged Ambient Air VOC Concentrations, Using Meteorological Data

A method of predicting point and path-averaged ambient air VOC concentrations is described. This method was developed for the case of a plume generated from a single point source, and is based on the relationship between wind directional frequency and concentration. One-minute means of wind direction and wind speed were used as inputs to a Gaussian dispersion model to develop this relationship. Both FTIR spectrometry and a whole-air sampling method were used to monitor VOC plumes during simulated field tests. One test set was also conducted using only whole-air samplers deployed in a closely-spaced network, thus providing an evaluation of the prediction technique free of any bias that might exist between the two analytical methods. Correlations between observed point concentrations and wind directional frequencies were significant at the 0.05 level in most cases. Predicted path-integrated concentrations, based on observed point concentrations and meteorological data, were strongly correlated with observed...

Effects of Wind Direction on Coarse and Fine Particulate Matter Concentrations in Southeast Kansas

Abstract Field data for coarse particulate matter ([PM] PM10) and fine particulate matter (PM2.5) were collected at selected sites in Southeast Kansas from March 1999 to October 2000, using portable MiniVol particulate samplers. The purpose was to assess the influence on air quality of four industrial facilities that burn hazardous waste in the area located in the communities of Chanute, Independence, Fredonia, and Coffeyville. Both spatial and temporal variation were observed in the data. Variation because of sampling site was found to be statistically significant for PM10 but not for PM2.5. PM10 concentrations were typically slightly higher at sites located within the four study communities than at background sites. Sampling sites were located north and south of the four targeted sources to provide upwind and downwind monitoring pairs. No statistically significant differences were found between upwind and downwind samples for either PM10 or PM2.5, indicating that the targeted sources did not contribute significantly to PM concentrations. Wind direction can frequently contribute to temporal variation in air pollutant concentrations and was investigated in this study. Sampling days were divided into four classifications: predominantly south winds, predominantly north winds, calm/variable winds, and winds from other directions. The effect of wind direction was found to be statistically significant for both PM10 and PM2.5. For both size ranges, PM concentrations were typically highest on days with predominantly south winds; days with calm/variable winds generally produced higher concentrations than did those with predominantly north winds or those with winds from “other” directions. The significant effect of wind direction suggests that regional sources may exert a large influence on PM concentrations in the area.

Satellite-Derived Cumulus Cloud Statistics for Western Kansas

Abstract Increasing world population, decreasing grain reserves and current farm total income levels have aroused interest in new methods that may lead to increased crop production across the Great Plains. Precipitation modification schemes are one such method. Success depends on many factors, especially knowledge of cumulus cloud characteristics during the growing season. We present some cumulus cloud statistics for the months May–September based on analysis of once-per-day satellite products for a limited region (western Kansas) and show that frequency, size and distance between cumulus elements vary substantially on a monthly and yearly basis across the study area. More clouds were recorded in the northwest and southeast portions of the study region. Areas of highest cloud numbers migrated from southeast to northwest from May to September for any given year and for the four-year sample. Eightysix percent of all observed clouds had radii less than 4 km with clouds more closely spaced across the central ...

Optimization of a Fourier transform infrared spectrometer during on-site pollution analysis

The field transportable Fourier transform infrared (FT-IR) spectrometer system developed at Kansas State University is now finishing the testing stage. The testing stage consisted of three parts: the measurements of (1) controlled releases of volatile organic compounds (VOC), (2) uncontrolled VOC releases at well documented sites, and (3) uncontrolled VOC releases at complex sites with little or no precharacterization1. Some measurements have been acquired in all three categories with most of the data acquisition taking place in the first two categories, which are discussed in these proceedings. These tests were developed to validate the qualitative and quantitative capabilities while enhancing the versatility and detection limits of the spectrometer system. The controlled VOC releases, for the most part, took place at the University of Kansas (KU). The KU tests utilized a co-monitoring technique, evacuated stainless steel canisters followed by GC/FID analysis, during the acquisition of the infrared data. The ability to monitor the concentrations of the released plume with another technique allowed for the comparison and examination of how varying parameters can affect the infrared spectrometer technique. The varying parameters that were addressed were wind, path length, temperature, barometric pressure, water and carbon dioxide concentration, and air borne particulates. One set of uncontrolled releases occurred at an active production facility. A list of the possible compounds that might be observed from the facility directly due to production was obtained. Infrared measurements were acquired at two different setup geometries down wind and one setup geometry up wind. The three path lengths were 390 meters, 500 meters, and 412 meters respectively. During these measurements two series of canister samples were obtained down wind and one series of canister samples were obtained up wind. The analyses of these canisters, on-going at this writing, is being performed by GC/FT-IR (matrix isolation). When the analysis from this method is complete the results will be compared. These two different data acquisitions have led to much insight into the capabilities of the spectrometer system and how varying parameters can affect the FT-IR spectrometers performance. Preliminary analysis of the spectroscopic data from both data acquisitions will be discussed.

Estimation of VOC emission rates from FTIR measurements and whole-air canister data

Methods of estimating VOC emission rates from a point source are being field tested by the University of Kansas, in cooperation with Region VII of the U.S. EPA and Kansas State University. The methods use path-integrated VOC concentrations, meteorological data, and a form of the Gaussian dispersion equation. VOC concentrations were derived both from a whole-air canister sampling method, with subsequent GC analysis, and from open-path FTIR measurements; estimated emission rates produced from the two analytical methods were compared. Canister-derived concentrations provided higher mean estimation accuracies than did FTIR measurements for both 1, 1, 1-Trichloroethane and toluene; however, for a third data set consisting of all other compounds released, FTIR measurements provided higher values. Estimation accuracy also was evaluated as a function of atmospheric stability and downwind distance; accuracy generally increased and variability decreased as stability increased; accuracy was better at longer than at 50 meters.

ATYPICAL PRECIPITATION MEASURES: COMPARISONS ALONG AN ENVIRONMENTAL GRADIENT, CENTRAL UNITED STATES

Similarities and differences among 11 precipitation measures from 11 central U.S. sites are described. Sites are arrayed along transects that cross a longitudinal environment gradient. Nine derived (precipitation days, hours, events, duration, traces to precipitation hours, four intensity ratios) and two measured (precipitation amounts, trace occurrence) variables are used. Hourly values for 10 growing seasons comprise the data. Measures are compared under normal, wet, and dry conditions. Inclusion of trace occurrences on comparisons is noted. Normal condition median values decrease westward; significant similarities exist among stations for all variables; trace inclusion raises median precipitation days and event numbers at western stations. Under dry conditions, medians are lower for all variables but overall sample characteristics are similar to normal conditions; trace data inclusion decreases contrasts with normal conditions; trace data inclusion (exclusion) increase (decreases) twofold between wet a...