Hydrogeology & Hydrology Program
Piedmont Region Water Quality	contact: David Bolton (dbolton@mgs.md.gov)

1. Collect water samples from approximately 50 sites that were sampled as part of the original ground-water study.
2. Evaluate ground-water quality with respect to data collected during the initial study, particularly with respect to land-use changes.

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A study of ground-water quality in the Piedmont region of Baltimore County, Maryland was conducted between 1994 and 1996 in a cooperative project between the Baltimore County Department of Environmental Protection (DEPRM), the Maryland Geological Survey (MGS), and the U.S. Geological Survey (USGS) (Bolton, 1998). That study provided (1) an evaluation of ground-water quality with respect to Federal drinking-water standards, land use, well characteristics, aquifer lithology, and other factors, and (2) baseline data to which future water-quality data can be compared to assess changes in ground-water quality over time. This project will resample the wells and springs to determine what changes, if any, have occurred in ground-water quality, and to identify factors associated with observed changes.

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Objective #1: Data collection:

1. Write a quality assurance (QA) project plan that describes sampling procedures, sample transport, QA sampling and objectives, data reduction and validation, and corrective actions.
2. Purchase necessary equipment and supplies.
3. Obtain permission to resample wells and springs.
4. Collect water samples from approximately 50 wells and springs. To the extent possible, samples will be sampled and processed as in the initial study. All samples will be analyzed for constituents listed in table 1 (constituents are discussed in the next section of the proposal). It is anticipated that water-quality analysis will be performed by the USGS National Water Quality Laboratory, as was done in the initial study.
5. Document changes in land use that may have occurred since the initial study at or near each site. This will be done using Maryland Office of Planning land-use coverage and by visual inspection of each sampling site.
6. Evaluate water-quality data for accuracy and completeness as it returns from laboratory.

Objective #2: Data evaluation:

1. Summarize all new data in a table similar to Table 8 in the original report (Bolton, 1998, p. 88-97). Compare the two data sets to evaluate overall changes in ground-water quality in the study area. This will be done by comparing the two tables and by using appropriate statistical methods such as Mann-Whitney and Kruskal-Wallis rank-sum tests.
2. Compare the old and new data for changes in ground-water quality in different land-use categories. Data will be organized in a figure similar to Figure 21 in the original report (Bolton, 1998, p. 55-57). The data will be compared visually and statistically.
3. Evaluate old and new data from sites which have had significant land-use or other changes since the initial study.
4. Analyze data in other ways that address the needs of the cooperating agencies.

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Water-quality constituents to be analyzed are listed in table 1. The constituent list, which includes major ions, selected pesticides, volatile organic compounds (VOCs), and radionuclides, was developed after many discussions between DEPRM and MGS personnel. Gross alpha-particle and beta-particle activity, which was not analyzed in the initial study, will provide an inexpensive screening method for radium and other radionuclides. Both short-term (analyzed within three days of sample collection) and long-term (analyzed again after 30 days) measurements of gross alpha and beta will be made. Samples containing more than 15 picocuries per liter gross alpha-particle activity will be resampled and analyzed specifically for radium-226 and radium-228. Pesticides will be analyzed using the same analytical method as in the initial study; approximately 10 additional samples will also be analyzed by USEPA Method 507 for comparison. It is anticipated that bacteriological samples will be collected by DEPRM personnel and analyzed for total coliform bacteria and E. coli.

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Quality assurance (QA) procedures will be established to ensure data quality. Prior to sample collection, a QA project plan will be written that describes all aspects of the project, including a project description, sampling procedures, QA objectives, analytical procedures, QA samples, and corrective action to be taken. QA samples will be collected in order to (1) ensure there is no sample contamination from sampling equipment; (2) document the effectiveness of decontamination procedures; and (3) document precision of measurements. QA samples will consist of trip blanks, field blanks, and field duplicates. Data from the QA samples will be analyzed immediately in order to take any corrective actions that may be necessary. Other QA activities will include (1) comparison of field and laboratory values of pH, alkalinity, and specific conductance; (2) comparison of analytical values of total dissolved solids to residue-on-evaporation; and (3) evaluation of charge-balance errors and selected parameter ratios.

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Bolton, D. W., 1998, Ground-water quality in the Piedmont region of Baltimore County, Maryland: Maryland Geological Survey Report of Investigations No. 66, 191 p.

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Table 1. Proposed water-quality constituents to be analyzed in samples from Baltimore County wells

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