Open-File Report 2004-1208
Concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) and Major and Trace Elements in Simulated Rainfall Runoff From Parking Lots, Austin, Texas, 2003
By Barbara J. Mahler, Peter C. Van Metre, and Jennifer T. Wilson
U.S. Geological Survey
Open-File Report 2004–1208 version 3—ONLINE ONLY
In cooperation with the City of Austin
The Press Release: http://www.usgs.gov/newsroom/article.asp?ID=1642
The Inquiry
The Response: http://tx.usgs.gov/Response.pdf
Abstract
Samples of creek bed sediment collected near seal-coated parking lots in Austin, Texas, by the City of Austin during 2001–02 had unusually elevated concentrations of polycyclic aromatic hydrocarbons (PAHs). To investigate the possibility that PAHs from seal-coated parking lots might be transported to urban creeks, the U.S. Geological Survey, in cooperation with the City of Austin, sampled runoff and scrapings from four test plots and 13 urban parking lots. The surfaces sampled comprise coal-tar-emulsion-sealed, asphalt-emulsion-sealed, unsealed asphalt, and unsealed concrete. Particulates and filtered water in runoff and surface scrapings were analyzed for PAHs. In addition, particulates in runoff were analyzed for major and trace elements. Samples of all three media from coal-tar-sealed parking lots had concentrations of PAHs higher than those from any other types of surface. The mean total PAH concentration in particulates in runoff from parking lots in use were 3,500,000, 620,000, and 54,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed (asphalt and concrete combined) lots, respectively. The probable effect concentration sediment quality guideline is 22,800 micrograms per kilogram. The mean total PAH (sum of detected PAHs) concentration in filtered water from parking lots in use was 8.6 micrograms per liter for coal-tar-sealed lots; the one sample analyzed from an asphalt-sealed lot had a concentration of 5.1 micrograms per liter and the one sample analyzed from an unsealed asphalt lot was 0.24 microgram per liter. The mean total PAH concentration in scrapings was 23,000,000, 820,000, and 14,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed asphalt lots, respectively. Concentrations of lead and zinc in particulates in runoff frequently exceeded the probable effect concentrations, but trace element concentrations showed no consistent variation with parking lot surface type.
Contents
Abstract
Introduction
Purpose and Scope
Site Selection
Sample-Collection Methods
Analytical Methods
PAHs in the Particulate Phase
PAHs in the Dissolved Phase
Major and Trace Elements in the Particulate Phase
Quality-Control Samples
PAHs and Major and Trace Elements in Simulated Rainfall Runoff
PAHs
Runoff From Test Plots
Runoff From Parking Lots in Use
Scrapings
Major and Trace Elements (Metals)
Runoff From Test Plots
Runoff From Parking Lots in Use
References Cited
Figures
1. |
Map showing location of parking lots for sampling of simulated runoff, Austin, Texas, 2003. |
|
2–7. |
Graphs showing: |
|
2. |
Rainfall for the sampling period as recorded at the National Weather Service Austin Camp Mabry station and dates washoff samples collected. |
|
3. |
Concentrations of total particulate polycyclic aromatic hydrocarbons (ΣPAHpart) in washoff samples from four test plots in Austin, Texas, 2003. |
|
4. |
Concentrations
of total dissolved polycyclic aromatic hydrocarbons (ΣPAHdiss)
in washoff samples from four test plots in Austin, Texas, 2003. |
|
5. |
Concentrations
of total particulate polycyclic aromatic hydrocarbons (ΣPAHpart)
in washoff samples from test plots and parking lots in use, Austin,
Texas, 2003. |
|
6. |
Concentrations
of total dissolved polycyclic aromatic hydrocarbons (ΣPAHdiss)
in washoff samples from test plots and parking lots in use, Austin,
Texas, 2003. |
|
7. |
Concentrations of total particulate polycyclic aromatic hydrocarbons (ΣPAHpart) in scrapings samples from test plot and parking lot surfaces in Austin, Texas, 2003. |
Tables
1. | Selected characteristics of sites for sampling simulated rainfall runoff from parking lots, Austin, Texas, 2003. | |
2. | Particulate-phase concentrations of polycyclic aromatic hydrocarbons in washoff and scrapings samples from parking lots, Austin, Texas, 2003. | |
3. | Dissolved-phase concentrations of polycyclic aromatic hydrocarbons in washoff samples from parking lots, Austin, Texas, 2003. | |
4. | Particulate-phase concentrations of major and trace elements in washoff samples from parking lots, Austin, Texas, 2003. | |
5. | Suspended sediment concentrations in washoff samples from parking lots, Austin, Texas, 2003. |