geophysical system verification - a commercial application

Commercial Application of the Physics-Based Test Strip and

Seeding Approach

Ryan Steigerwalt, P.G., Weston Solutions, Inc.Jim Austreng, P.E., California Department of Toxic Substances Control

C. Scott Goulart, Aerojet-General Corporation

UXO/Countermine/Range Forum 2009Orlando, Florida

Commercial ApplicationGeophysical System VerificationAerojet Chino Hills Facility, CA

TALKING POINTS• Introduction and Conceptual Site Model • Project planning and requirements• Implementation of the Geophysical System

Verification (GSV) process– Planning and development– Test Strip construction– Seeding program– Operations– Results


INTRODUCTION• Project site located in Chino

Hills, CA• Facility owned by Aerojet-

General Corporation• Perform MEC detection and

removal in areas not previously investigated

• Use DGM in all accessible areas

• Perform mag & dig surveys in all other areas where possible

• Work was conducted with DTSC oversight

• Dec 2008 – Feb 2009


CONCEPTUAL SITE MODEL

• CSM identified anticipated munitions and facility uses

• Extensive geophysical prove-outs were conducted at the facility in 2004

• Evaluated detection capabilities of various instruments and techniques

• Reported the type and quality of data required for subsequent MEC detection and removal activities


WORK PLAN• Use results from

previous GPO• Develop data

collection parameters and quality control

• Perform a limited GPO and gain concurrence

• Mobilize remainder of crew

• Collect data


PROJECT REQUIREMENTS

• In November 2008, wildfire struck the facility and cleared vegetation

• Need to perform technically defensible work, quickly, before vegetation returned

• Mobilize ASAP


FIELD VARIANCE• Began site setup• Preparing to perform limited GPO• Project team discussed GSV and potential

application– No GPO grid construction– Start collecting data immediately– No required review cycle– Joint QC/QA– Can continuously monitor performance

• Developed a brief field variance to document GSV approach- test strip construction and seeding

• Gained regulatory concurrence


GSV DESIGN• Test Strip Construction

– Seed anticipated munitions items at detection depth objectives

– Place seeds at least favorable orientation

– Establish multiple Test Strips if necessary to increase efficiency

– Perform daily to evaluate equipment functionality

Description Quantity Orientation Depth* 30-mm Projectile 2 horizontal 10 inches** 30-mm Projectile 2 horizontal 13 inches*** 25-mm Projectile 2 horizontal 11 inches**** 20-mm Projectile 2 horizontal 8 inches****

Notes:* Depth is equal to detection performance metrics established in Final Work Plan.**Detection performance metric for EM61-MK2.***Detection performance metric for Schonstedt.****Detection performance metric for EM61-MK2 and Schonstedt.


GSV DESIGN• Seeding Program

– Use similar items and burial depths as Test Strips

– Initially place one seed within each 100-ft x 100-ft grid block

– Relax seed frequency to one seed per acre if performance is acceptable


GSV IMPLEMENTATION• Equipment

– EM61-MK2 towed sled– 4 sensor– RTK-GPS Navigation

• Test Strip– Perform background and

baseline survey prior to production mapping

– Run Test Strip daily with instrumentation

– Perform concurrent with standardized QC function tests

– Evaluate response and monitor results


SURVEY SUMMARY• Digital Geophysical

Mapping Summary– Completed

approximately 9 total acres

– Includes rough and steep terrain

– Spanned several weeks– All DGM was performed

using a towed array sled


TEST STRIP 1 RESULTS

Day 1 (Baseline)

Day 2

Day 3

Day 4

Day 5

Day 6


TEST STRIP 2 RESULTSDay 8

Day 9

Day 10

Day 11


TEST STRIP SUMMARYItem # 1 2 3 4 5 6 7 8

Item Description30-mm

Projectile

30-mm

Projectile

30-mm

Projectile

30-mm

Projectile

25-mm

Projectile

25-mm

Projectile

20-mm

Projectile

20-mm

Projectile

Item Depth (inches) 10-inches 10-inches 13-inches 13-inches 11-inches 11-inches 8-inches 8-inches

Test Strip 1

1/07/09 10.25 7.90 13.33 13.81 11.44 6.46 5.72 6.40

1/08/09 10.12 4.89 14.18 9.22 9.71 6.31 7.01 3.04

1/11/09 8.09 7.43 12.49 12.68 7.69 6.24 6.99 3.11

1/13/09 7.43 4.90 13.74 7.58 9.90 5.42 6.50 5.40

1/29/09A 8.51 4.40 14.88 8.81 10.07 6.14 7.62 4.00

1/30/09 9.68 5.16 12.85 6.75 8.75 5.58 7.46 4.97

Mean (mV) 9.01 5.78 13.58 9.81 9.59 6.02 6.88 4.49

Std Dev 1.2 1.5 0.9 2.8 1.3 0.4 0.7 1.3

Test Strip 2

1/29/09B 17.71 6.94 15.69 3.99 12.25 11.32 9.46 4.93

1/30/09B 24.42 9.24 16.69 6.86 21.98 8.18 10.38 6.19

1/31/09A 19.50 8.14 17.68 5.06 17.59 9.76 10.93 6.42

1/31/09B 22.24 8.23 18.02 5.18 20.43 9.29 12.10 6.45

Mean (mV) 20.97 8.14 17.02 5.27 18.06 9.64 10.72 5.99

Std Dev 3.0 0.9 1.0 1.2 4.3 1.3 1.1 0.7

Direction of Travel


SEEDING RESULTS• 19 total seeds (30mm,

25mm, 20mm)• Check response against

Test Strip results

1

2

3

4

5

0.0 5.0 10.0 15.0 20.0 25.0 30.0

20mm Projectile Seed

1

2

3

4

5

6

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0


12345678

0.0 5.0 10.0 15.0 20.0 25.0 30.0


Response (mV)

Response (mV)

Response (mV)

Test Strip Avg ~6 mV



+xSeed

Target


QUALITY ASSURANCE• Regulatory site visits• Industry Standard Targets and inert items

– 1-inch by 4-inch pipe nipples– Vertical (most favorable) at 11-inches– Horizontal (least favorable) at 7-inches

Grid Item Depth Orientation Y X Type

6719/6037 Small IST 11in Vertical 12326050.66 1416776.02 QA

6719/6037 20mm 8in Horizontal 12326050.20 1416774.42 QA

6720/6137 Small IST 11in Vertical 12326192.54 1416795.16 QA

6521/6239 Small IST 7in Horizontal 12326275.29 1416612.33 QA




SENSOR RESPONSE CURVE

0.0 10.0 20.0 30.0 40.0 50.0 60.01.0

10.0

100.0

1000.0

Small Industry Standard Target

MFO LFO

Depth Below Ground Surface (inches)

CH3

Resp

onse

(mV)

Seed Seed


BENEFITS• Means to monitor

geophysical system performance daily and consistently

• Shortened schedule• Re-allocated resources to

risk reduction efforts– Planning variance drafted

onsite– No duplicate QC/QA– Began production mapping

next day


LESSONS LEARNED

• Still need to plan ahead– Define objectives– Seeding program– Schedule

• Ensure Test Strip seeds are isolated from other influence

• Use Industry Standard Targets to reduce variability

• Reality works


QUESTIONS?

Montauk Monster

geophysical system verification - a commercial application

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