Skip directly to search Skip directly to A to Z list Skip directly to site content




The 1995 realtime air monitoring collected on one resident's property were high enough to have resulted in an odor complaint, if the contaminants were xylene, toluene, ethylbenzene, and/or methyl ethyl ketone. The odor thresholds for these compounds are as follows: xylene (0.08-3.7 ppm), toluene (approximately 8 ppm), ethylbenzene (approximately 2 ppm), and methyl ethyl ketone (5-8 ppm). The headache and dizziness health effects reported by the residents are consistent with exposures to these compounds in the 1 to 5 ppm range for several hours [8, 9, 10, 11]. These effects should cease after exposure stops. However, without confirmatory sampling/analysis data, it cannot be determined if this event resulted in the reported symptoms. It should be noted that the target volatile organic contaminants found at the site are also commonly found in household cleaning supplies and in gasoline.

If the contaminants detected with the realtime instrument were xylene, toluene, ethylbenzene, and/or methyl ethyl ketone, it is likely that the respective ATSDR inhalation minimal risk levels (MRLs) for the contaminants were exceeded. MRLs are defined as an estimate of daily human exposure to a dose of a chemical that is likely to be without an appreciable risk of adverse noncancerous effects over a specified duration of exposure. In addition, the site-specific ARARs were likely exceeded. Table 7 summarizes these health-based values.

Results of the annual perimeter air sampling and the sampling conducted by ERT in 1996 indicate no exceedances of the site ARARs. However, some of the contaminant concentrations approach the ARARs (xylenes) and the annual sampling's detection limit for benzene is above the ARAR. Results of the worker's breathing zone samples confirm that the contaminants (benzene, toluene, ethyl benzene, xylenes, and methyl ethyl ketone) are present in the waste material. More frequent perimeter sampling would assist in determining if the limited sampling results collected to date are representative of emissions during site operations and during weather conditions (i.e., inversions) that would decrease the dispersion of the contaminants into the atmosphere.


  • The information about air stripper emissions is lacking. In order to determine if off-site populations are being exposed to the emissions, stack sampling and dispersion modeling are conducted. At a minimum, groundwater contaminant concentrations could be measured and modeled.
  • Realtime air monitoring conducted downwind of operations reveal readings up to 258 ppm. Collecting grab samples for laboratory analyses when OVA readings are elevated would assist in determining which compounds are present at these levels.
  • No realtime particulate monitoring is occurring during site earthmoving/spreading activities. Similarly, worker monitoring and perimeter sampling for metals that are elevated in on-site soils do not appear to be occurring. Realtime monitoring and time-weighted sampling is necessary to ensure that exposures to on-site workers and off-site populations is below the applicable worker standards and community ARARs.
  • From the information reviewed, it was not possible to determine If the operator of the backhoe was included in the breathing zone worker sampling program. It appears that the realtime OVA readings taken in the backhoe cab are above the 100 ppm level that should result in temporary relocation of the worker to a clean area. Continuous realtime monitoring and periodic breathing zone sampling in the cab of this backhoe (when in operation), along with other equipment/vehicles used for earthmoving/ spreading activities would assist in determining if the operators are in the appropriate level of respiratory protection.
  • Although not part of the air emission concerns, ATSDR has not been provided with the area well sample results for review.

Next Section          Table of Contents The U.S. Government's Official Web PortalDepartment of Health and Human Services
Agency for Toxic Substances and Disease Registry, 4770 Buford Hwy NE, Atlanta, GA 30341
Contact CDC: 800-232-4636 / TTY: 888-232-6348

A-Z Index

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #