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Geology topics

S.J. Pollock

Publications and source records attributed to S.J. Pollock.

4 recordsLinked to original sources
USGS1984

Effectiveness of highway drainage systems in preventing salt contamination of ground water, Route 25 from Wareham to the Cape Code Canal, Massachusetts

A study to determine the relative effectiveness of specially designed highway drainage features in preventing salt contamination of ground water was designed to compare four different drainage designs along a new highway in Massachusetts. At the control site, no attempt will be made to prevent salt from entering the ground. At the other three sites, different combinations of drains and impermeable berms have been designed to prevent salt contamination of ground water. To evaluate the effectiveness of the drainage designs, a salt balance will be prepared at each site over 5 years of highway use. The amount of salt applied to the highway will be compared to the amounts in the ground water or diverted to the drainage systems. Salt loads in ground water will be determined from sodium and chloride concentrations in water from about 80 wells and from aquifer porosity estimated from geophysical logs and lithologic samples. Salt loads in the drainage systems will be estimated from flow and specific conductance with the use of stage-to-discharge and conductance-to-concentrations rating curves. (USGS)

Water-Resources Investigations Report↗
USGS1981

Hydrologic effects of highway-deicing chemicals in Massachusetts

Methods of estimating annual mean and annual maximum chloride concentrations and sodium concentrations in streams were developed using multiple and simple linear regression techniques and data collected during the 1972-77 water years. Independent variables are easily obtainable parameters such as total salt application within a basin, annual precipitation, and drainage basin characteristics. Methods for obtaining gross estimates of chloride loads and sodium loads from salt-application data and estimates of nonhighway-related chloride and sodium were suggested. A chloride budget was calculated for a small drainage basin containing a section of interstate highway. The chloride budget was described in terms of the percentages in direct runoff to the stream, in ground-water discharges to the stream, in storage in the ground, and in the amount unaccounted for. Attempts were made to relate chloride concentrations in ground water adjacent to highways to quantities of salt applied to the highways on an annual basis, annual precipitation, depth of the wells below land surface, depth of wells below the water table, and distance of well from edge of pavement. Little correlation was observed between annual salt-application values and annual mean chloride concentrations in ground water near highways. The irregular distribution of highway runoff, due to topographic differences between sites, and variations in salting and runoff during individual storm events seem to affect correlation between quantities of salt applied and chloride concentrations in ground water near highways. (USGS)

Open-File Report↗
USGS1981

Hydrologic effects of highway-deicing chemicals in Massachusetts; executive summary

Methods of estimating annual mean and annual maximum chloride concentrations in streams were developed through multiple and simple linear regression techniques using data collected during the 1972-77 water years. Independent variables are easily obtainable parameters, such as total salt application within a basin, annual precipitation, and drainage basin characteristics. Methods for obtaining gross estimates of chloride loads and sodium loads from salt-application data and estimates of nonhighway-related chloride and sodium were suggested. A chloride budget was calculated for a small basin draining a section of interstate highway. The chloride budget was described in terms of the percentages in direct runoff to the stream, in ground-water discharges to the stream, in storage in the ground, and the amount unaccounted for. Attempts were made to relate chloride concentrations in ground water adjacent to highways to quantities of salt applied to the highways on an annual basis, annual precipitation, depth of the wells below land surface, depth of the well below water table, and the distance of the well from the edge of the pavement. Little correlation was observed between annual salt-application values and annual mean chloride concentrations in ground water near highways. The irregular distribution of highway runoff, due to topographic differences between sites, and variations in runoff resulting from individual storms seem to be the causes of the lack of significant correlation between annual quantities of salt applied and chloride concentrations in ground water near highways. (USGS)

Open-File Report↗