Dames & Moore, 1999 - USDA Forest Service

December 1 1, 1998
Sediment Data, Fall 1998, Holden Mine
Page 3
6. Internal Standards,(lCP MS analysis only) - Acceptab!e
7. ICP Interference Check (ICP analysis only) - Acceptable
8. Laboratory Control Sample (LCS) - Acceptable
A standard reference material (SRM) was analyzed in lieu of a typical LCS. Lead recovery
(124%) in the SRM associated with this sample set was above the typical LCS control limits of
80 to 120%. However, the recovery was within the advisory range published by the supplier.
Data were not qualified based on the LCS recoveries.
9. Laboratory Duplicate Sample - Acceptable
10. Field Duplicate
Field replicates were collected and labeled LUC-SED-101598-1A, -1~; and -1C. Data were
comparable for all analyses. It is noted that the relative percent difference for cadmium was 53%. Data
qualifiers were not assigned based on the field replicate results.
11. Matrix Spike
A matrix spike was performed on sediment sample STE-SED-101698-1. Aluminum (210%) and
iron (51 1%) recoveries were outside of the control limits (75-125%). The concentration of aluminum and
iron in the original sample exceeded the spiking concentration by greater than 4X. Data qualification was
not required.
12. ICP Serial Dilution (ICP analysis only) - Acceptable
13. Detection Limits - ~cceptable
14. Type of Review - Standard
15. Overall Assessment of Data
The usefulness of the data is based on EPA guidance documents listed above. Upon
consideration of the information presented above, the data are acceptable except where flagged with
data qualifiers that modify the usefulness of the individual values.
Conventional Analvses
Samples were analyzed for pH, total solids, total volatile solids (lVS), acid volatile sulfides
(AVS), total organic carbon (TOC), and grain size by EPA or other appropriate methodology identified in
the introduction to this report.
1. Hold Time
The analysis for pH in the sediment samples was performed 14 days after sample collection. As
pH generally should be analyzed as soon as possible after sample collection, the data is qualified as
estimated and flagged "J" accordingly.
DAMES & MOORE