FINAL SAMPLING AND ANALYSIS PLAN - Documents for Moffett Field

8 Worksheet #15, Table 15-4 Change the project action limit for lead
to the September 2009 California Human
Health Screening Level (CHHSL). The
California Office of Environmental
Health Hazard Assessment recalculated
the cleanup number based on a level of
lead in soil that could result in up to a 1
microgram per deciliter (µg/dL) increase
in blood lead level.. The re-calculation
reduced the CHHSL for lead to 320
milligrams per kilogram for
commercial/industrial exposure. If the
Navy elects not to make this
recommended change, provide
justification for the decision.
9 Worksheet #16 Revise the schedule to show the correct
date(s) for distribution of the Work Plan.
10 Worksheet #17 Describe the steps that will be taken if
the soil samples from 12 inches below
ground surface contain chemicals of
concern at concentrations greater than the
screening criteria. The Navy has not
included a sampling contingency for this
scenario.
11 Worksheet #17 Revise the soil sampling locations to
collect representative soil samples from
each soil area. Soil contamination, if
present, likely is the result of deposition
of contaminated particles that slough off
the hangar. Because these particles could
be transported via wind prior to
deposition on the soil surface, there is no
basis for sampling solely at the locations
closest to the hangar.
The project action limit for lead for
import soil will be changed to 320
milligrams per kilogram.
Comment noted. Project schedule will
be updated.
If the 12 inch samples exceed the
action limit, then additional
excavation will occur until the action
levels are met. The Pre-Final Draft of
the SAP will be revised accordingly.
The soil sampling strategy will be
revised. A grid approach will be
utilized to collect soil samples from
soil areas on the east side of the
Hangar. The grid will cover the entire
soil area. Sample results will be
provided to both EPA and Water
Board for consultation on the specific
soil removal approach.
Response to Comments on Draft Sampling and Analysis Plan
Moffett Field, California
DCN: AMEC-8816-0005-0041
April 2010
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