24-100334-Soil Sample Report-01.31.24Cobalt Geosciences, LLC
P.O. Box 1792
North Bend, WA 98045
www.cobaltgeo.com (206) 331-1097
November 28, 2023
Muhammad Saad Mohyuddin
saadmohi@googlemail.com
RE: Environmental Soil Sampling
Proposed Residence
1013 S. 295th Place
Federal Way, Washington
In accordance with your authorization, Cobalt Geosciences, LLC has prepared this letter to
present the result of our recent soil sampling and subsequent analytical soil testing.
The site is within the Tacoma Smelter Plume area and soil testing is typically required for new
development to determine if significant levels of arsenic and lead are present in the near surface
soils.
We collected soil samples from locations within the area of the proposed development near the
ground surface and at a slightly greater depth (6 to 12 inches) for analytical testing. The testing
was performed by OnSite Environmental, Inc. using the EPA 6010 Method for Arsenic and Lead.
Only one soil sample (3A) was above non-detectable levels of arsenic in soil (12 parts per million
(ppm)). Lead values ranged from non-detect (ND) up to 78 ppm, with most values below 20 ppm.
We note that the duff composite sample had values of ND for Arsenic and 10 ppm for lead. All
values were lower than the required clean up levels for these constituents, which is 20 ppm for
arsenic and 250 ppm for lead.
The attached Figure 1 shows sample locations. Samples noted with an A are for the 6 to 12 inch
depth. All other samples were 0 to 6 inches in depth. Composite sample is for forest duff
materials.
CLOSURE
Our services are limited to soil sampling only and do not include recommendations for soil
removal or any other environmental services.
November 28, 2023
Page 2 of 2
Soil Sampling
www.cobaltgeo.com (206) 331-1097
Sincerely,
Cobalt Geosciences, LLC
11/28/2023
Phil Haberman, PE, LG, LEG
Principal
N
SOIL
SAMPLE
LOCATIONS
FIGURE 1
1
132nd Street SE
Proposed Residence
295th Place 1013 S.
Federal Way, Washington
Cobalt Geosciences, LLC
P.O. Box 1792
North Bend, WA 98045
(206) 331-1097
www.cobaltgeo.com
phil@cobaltgeo.com
3
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: November 21, 2023
Samples Submitted: November 13, 2023
Laboratory Reference: 2311-116
Project: 1013 S. 295th Pl
TOTAL METALS
EPA 6010D
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: 1
Laboratory ID: 11-116-01
Arsenic ND 13 EPA 6010D 11-17-23 11-17-23
Lead 44 6.6 EPA 6010D 11-17-23 11-17-23
Client ID: 2
Laboratory ID: 11-116-02
Arsenic ND 15 EPA 6010D 11-17-23 11-17-23
Lead 25 7.5 EPA 6010D 11-17-23 11-17-23
Client ID: 3
Laboratory ID: 11-116-03
Arsenic ND 15 EPA 6010D 11-17-23 11-17-23
Lead 28 7.3 EPA 6010D 11-17-23 11-17-23
Client ID: 4
Laboratory ID: 11-116-04
Arsenic ND 17 EPA 6010D 11-17-23 11-17-23
Lead 22 8.4 EPA 6010D 11-17-23 11-17-23
Client ID: 5
Laboratory ID: 11-116-05
Arsenic ND 11 EPA 6010D 11-17-23 11-17-23
Lead 32 5.7 EPA 6010D 11-17-23 11-17-23
Client ID: 6
Laboratory ID: 11-116-06
Arsenic ND 12 EPA 6010D 11-17-23 11-17-23
Lead 18 6.0 EPA 6010D 11-17-23 11-17-23
Client ID: 7
Laboratory ID: 11-116-07
Arsenic ND 14 EPA 6010D 11-17-23 11-17-23
Lead 38 6.9 EPA 6010D 11-17-23 11-17-23
4
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: November 21, 2023
Samples Submitted: November 13, 2023
Laboratory Reference: 2311-116
Project: 1013 S. 295th Pl
TOTAL METALS
EPA 6010D
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: 8
Laboratory ID: 11-116-08
Arsenic ND 13 EPA 6010D 11-17-23 11-17-23
Lead 8.7 6.3 EPA 6010D 11-17-23 11-17-23
Client ID: 9
Laboratory ID: 11-116-09
Arsenic ND 16 EPA 6010D 11-17-23 11-17-23
Lead 11 8.0 EPA 6010D 11-17-23 11-17-23
Client ID: 10
Laboratory ID: 11-116-10
Arsenic ND 13 EPA 6010D 11-17-23 11-17-23
Lead 11 6.4 EPA 6010D 11-17-23 11-17-23
Client ID: 11
Laboratory ID: 11-116-11
Arsenic ND 11 EPA 6010D 11-17-23 11-17-23
Lead ND 5.4 EPA 6010D 11-17-23 11-17-23
Client ID: 12
Laboratory ID: 11-116-12
Arsenic ND 12 EPA 6010D 11-17-23 11-17-23
Lead 15 5.9 EPA 6010D 11-17-23 11-17-23
Client ID: 1A
Laboratory ID: 11-116-17
Arsenic ND 13 EPA 6010D 11-17-23 11-17-23
Lead 12 6.7 EPA 6010D 11-17-23 11-17-23
Client ID: 2A
Laboratory ID: 11-116-18
Arsenic ND 11 EPA 6010D 11-17-23 11-17-23
Lead ND 5.3 EPA 6010D 11-17-23 11-17-23
5
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: November 21, 2023
Samples Submitted: November 13, 2023
Laboratory Reference: 2311-116
Project: 1013 S. 295th Pl
TOTAL METALS
EPA 6010D
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: 3A
Laboratory ID: 11-116-19
Arsenic 12 12 EPA 6010D 11-17-23 11-17-23
Lead 78 6.0 EPA 6010D 11-17-23 11-17-23
Client ID: 8A
Laboratory ID: 11-116-20
Arsenic ND 11 EPA 6010D 11-17-23 11-17-23
Lead 8.8 5.5 EPA 6010D 11-17-23 11-17-23
Client ID: Composite
Laboratory ID: 11-116-21
Arsenic ND 12 EPA 6010D 11-17-23 11-17-23
Lead 10 6.0 EPA 6010D 11-17-23 11-17-23
6
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: November 21, 2023
Samples Submitted: November 13, 2023
Laboratory Reference: 2311-116
Project: 1013 S. 295th Pl
TOTAL METALS
EPA 6010D
QUALITY CONTROL
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
METHOD BLANK
Laboratory ID: MB1117SM1
Arsenic ND 10 EPA 6010D 11-17-23 11-17-23
Lead ND 5.0 EPA 6010D 11-17-23 11-17-23
Source Percent Recovery RPD
Analyte Result Spike Level Result Recovery Limits RPD Limit Flags
DUPLICATE
Laboratory ID: 11-177-05
ORIG DUP
Arsenic ND ND NA NA NA NA NA 20
Lead ND ND NA NA NA NA NA 20
MATRIX SPIKES
Laboratory ID: 11-177-05
MS MSD MS MSD MS MSD
Arsenic 95.8 96.9 100 100 ND 96 97 75-125 1 20
Lead 251 252 250 250 ND 101 101 75-125 0 20
7
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: November 21, 2023
Samples Submitted: November 13, 2023
Laboratory Reference: 2311-116
Project: 1013 S. 295th Pl
% MOISTURE
Date
Client ID Lab ID % Moisture Analyzed
1 11-116-01 25 11-17-23
2 11-116-02 33 11-17-23
3 11-116-03 31 11-17-23
4 11-116-04 40 11-17-23
5 11-116-05 12 11-17-23
6 11-116-06 17 11-17-23
7 11-116-07 28 11-17-23
8 11-116-08 20 11-17-23
9 11-116-09 38 11-17-23
10 11-116-10 22 11-17-23
11 11-116-11 8 11-17-23
12 11-116-12 16 11-17-23
1A 11-116-17 25 11-17-23
2A 11-116-18 6 11-17-23
3A 11-116-19 17 11-17-23
8A 11-116-20 9 11-17-23
Composite 11-116-21 17 11-17-23
8
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Data Qualifiers and Abbreviations
A - Due to a high sample concentration, the amount spiked is insufficient for meaningful MS/MSD recovery data.
B - The analyte indicated was also found in the blank sample.
C - The duplicate RPD is outside control limits due to high result variability when analyte concentrations are
within five times the quantitation limit.
E - The value reported exceeds the quantitation range and is an estimate.
F - Surrogate recovery data is not available due to the high concentration of coeluting target compounds.
H - The analyte indicated is a common laboratory solvent and may have been introduced during sample
preparation, and be impacting the sample result.
I - Compound recovery is outside of the control limits.
J - The value reported was below the practical quantitation limit. The value is an estimate.
K - Sample duplicate RPD is outside control limits due to sample inhomogeneity. The sample was
re-extracted and re-analyzed with similar results.
L - The RPD is outside of the control limits.
M - Hydrocarbons in the gasoline range are impacting the diesel range result.
M1 - Hydrocarbons in the gasoline range (toluene-naphthalene) are present in the sample.
N - Hydrocarbons in the lube oil range are impacting the diesel range result.
N1 - Hydrocarbons in diesel range are impacting lube oil range results.
O - Hydrocarbons indicative of heavier fuels are present in the sample and are impacting the gasoline result.
P - The RPD of the detected concentrations between the two columns is greater than 40.
Q - Surrogate recovery is outside of the control limits.
S - Surrogate recovery data is not available due to the necessary dilution of the sample.
T - The sample chromatogram is not similar to a typical ____________.
U - The analyte was analyzed for, but was not detected above the reported sample quantitation limit.
U1 - The practical quantitation limit is elevated due to interferences present in the sample.
V - Matrix Spike/Matrix Spike Duplicate recoveries are outside control limits due to matrix effects.
W - Matrix Spike/Matrix Spike Duplicate RPD are outside control limits due to matrix effects.
X - Sample extract treated with a mercury cleanup procedure.
X1 - Sample extract treated with a sulfuric acid/silica gel cleanup procedure.
X2 - Sample extract treated with a silica gel cleanup procedure.
Y - The calibration verification for this analyte exceeded the 20% drift specified in methods 8260 & 8270, and
therefore the reported result should be considered an estimate. The overall performance of the calibration
verification standard met the acceptance criteria of the method.
Y1 - Negative effects of the matrix from this sample on the instrument caused values for this analyte in the bracketing
continuing calibration verification standard (CCVs) to be outside of 20% acceptance criteria. Because of this,
quantitation limits and sample concentrations should be considered estimates.
Z -
ND - Not Detected at PQL
PQL - Practical Quantitation Limit
RPD - Relative Percent Difference