The SCBPP used performance-based quality assurance
objectives for sediment chemistry. Each
laboratory was to have demonstrated initial
capability and ongoing performance. The SCBPP
Quality Assurance Project Plan lists minimum
ongoing QA/QC requirements for sediment chemistry
analysis. Included in this data set are QA/QC
documentation for: Laboratory blanks -
minimum 1 per batch, < 3 x MDL Matrix
Spike(s) - minimum 1 per batch; 50 - 120% recovery
for 80% of the organic analytes or 70 - 120%
recovery for 80% of the inorganic analytes;
relative difference of duplicate organic or
inorganic analysis < 30%. Reference
Materials (CRM or LCM) - minimum 1 per batch;
within 30% of certified value for organic analytes
10 x MDL or within 20% of certified value for
inorganic analytes > 10 x MDL; < 30% percent
difference of organic or inorganic analytes > 10 x
MDL for all batches combined. Certified Reference
Material (CRM) for organics was NIST Standard
Reference Material 1941a. Certified Reference
Material (CRM) for inorganics was National
Research Council of Canada MESS-2. Each
laboratory provided its own LCM. Duplicate
samples - no applicable requirement for organics.
Relative percent difference for inorganics < 20%.