Gasco-Siltronic Technical Documents | Region 10 | US EPA

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Gasco-Siltronic Technical Documents

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Field Oversight Report U.S. Moorings Substantial Product Investigation Gasco Sediments Site, Portland, Oregon (PDF) (149 pp, 32MB) - February 2014

U.S. Moorings Sediment Investigation Report (PDF) (177 pp, 8.8MB) - January 24, 2014

Environmental Monitoring Report - Third and Fourth Quater 2012 (PDF) (726 pp, 65.5MB) - December 2013

Groundwater Source Control Extraction System Test (PDF) (211 pp, 20.4MB) - December 23, 2013

Data Report for NW Natural Sediment Characterization Adjacent to U.S. Moorings Site - Addendum 1 to the Project Area Identification Report Quality Assurance Project Plan (PDF) (61 pp, 6.2MB) - December 23, 2013

Gasco Treatment System Outfall Recontamination Evaluation (PDF) (18 pp, 864K) - December 2013

Fill WBZ Trench Investigation Work Plan (PDF) (322 pp, 26.8MB) - November 2013

Groundwater Source Control Extraction System Test Plan (PDF) (247 pp, 17MB) - November 2013

U.S. Government Moorings: Geotechnical and Sediment Investigation Report (PDF) (162 pp, 2.1MB) - October 11, 2013

Fill Zone Well Installation Work Plan (PDF) (11 pp, 1.1MB) - August 2013

Hydraulic Source Control and Containment System, Groundwater Model Update Report (PDF) (39 pp, 4.4MB) - July 2013

Draft Study Design for Sediment Characterization Adjacent to U.S. Moorings Site (PDF) (14 pp, 1.3MB) - July 2013

Environmental Monitoring Report - First and Second Quarter 2012 (PDF) (699 pp, 48.3MB) - May 2013

Environmental Monitoring Report - Third and Fourth Quarter 2011 (PDF) (660 pp, 52MB) - November 2012

NW Natural Proposal to Complete Additional Field Visual Surveys at the Gasco Sediments Site during August and September 2012 (PDF) (21 pp, 1.2MB) - July 2012

Environmental Monitoring Report for the First and Second Quarter 2011 (PDF) (649 pp, 48.5MB) - July 2012

Gasco Sediments Site Draft Engineering Evaluation /Cost Analysis (EE/CA Report, draft, undergoing EPA review for incorporation into the Harborwide Feasibility Study (PDF) (2355 pp, 81MB) - May 2012

Environmental Monitoring Report - Third and Fourth Quarter 2010 (PDF) (645 pp, 28MB) - March 2012

Revised Groundwater Source Control Construction Design Report (PDF) (155 pp, 35MB) - January 2012

Monthly Report and Removal Area Visual Inspection for November 2011 (PDF) (6 pp, 533K) - November 2011

Draft Technical Briefing Presentation for the Engineering Evaluation and Cost Analysis (PDF) (22 pp, 3.8MB, to start) - October 2011

Field Oversight Report for Segment 2 Capture Zone Field Test, GASCO/Siltronics (with photos) (PDF) (545 pp, 58MB) - August 2011

Gasco Field Oversight Report; Data Gaps Investigation (with photos) (PDF) (299 pp, 26MB) - May 2011

Segment 2 Field Tests of the Programmable Logic Control & Variable Frequency Drive Well Pumps (PDF) (39 pp, 5.9MB) - May 2011

Groundwater Source Control Final Design Report (PDF) (1179 pp, 74MB) - May 2011

Remedial Investigation Data Summary Report - April 2011(PDF) (364pp, 8MB) - April 2011

Scope of Work for Benthic Toxicity Retesting (PDF) (19 pp, 2MB) - April 2011

Bioassay Interpretation Summary and Recommendations (PDF) (13 pp, 1.3MB) - March 2011

Segment 2 Capture Zone Field Test Report (PDF) (240 pp, 14.4MB) - March 2011

Segment 2 Capture Zone Test, Data Summary Memorandum (PDF) (99 pp. 10MB) - January 2011

Project Area Identification Report and Data Gaps QAPP (PDF) (691 pp. 20MB) - July 2010

Environmental Monitoring Report Third and Fourth Quarter 2009 NW Natural Gasco Facility (PDF) (463pp. 17MB) - June 2010

Data Summary Report: Year 3 Event 2 Long-term Event Monitoring (PDF) (587 pp. 20MB) - April 2010

First and Second Quarter Environmental Monitoring Report (PDF) (371 pp. 14MB) - January 29, 2010

Final Work Plan Gasco Sediments Cleanup Action (PDF) (478 pp. 56.5MB, to start) - January 2010

NW Natural and Siltronic Groundwater Treatment Pilot Plant Report (PDF) (111 pp. 1.2MB) - December 2009

Map of 1996 high water mark for Arkema, Siltronic, and Gasco Sites (PDF) (1 page 310K) - November 2009

Data Summary Report–Year 3 Event 1 Long-term Pilot Cap Monitoring, Removal Action (PDF) (88 pp. 6.5MB) - November 2009

Groundwater Source Control Interim Design Report (PDF) (507 pp. 31.5MB) - November 2009

Health and Safety Plan for Gasco Field Activities for Capture Zone Field Test Plan (PDF) (54 pp. 945K) - November 2009

Draft Work Plan for the Gasco Sediment Cleanup Action (PDF) (469 pp. 48.7MB) - October 9, 2009

Capture Zone Field Test Plan (PDF) (102 pp. 4.9MB) - September 2009

Siltronic Performance Monitoring Plan (PDF) (35 pp. 1.1MB) - August 31, 2009

Environmental Monitoring Report, Third and Fourth Quarter 2008 (PDF) (357 pp. 12.1MB) - August 10, 2009.

Annual Data Evaluation Monitoring Report Year 2 Long Term Pilot Cap Monitoring (PDF) (274 pp. 28.1MB) - July 2009

Revised Wastewater Pilot Plant Testing Plan (PDF) (44 pp. 645K) - June 2009

Vibration Study Data Report Gasco Siltronic Construction (PDF) (148 pp. 5.5MB) - May 2009

Data Summary Report Year 2 Event 2 Long-Term Pilot Cap Monitoring (PDF) (619 pp. 25.5MB) - May 2009

Evaluation of Potential DNAPL Mobilization in Former Effluent Pond Area by Shoreline Source Control Extraction Wells (PDF) (18 pp. 4.6MB) - March 2009

Environmental Monitoring Report Summer 2007 through Spring 2008. (PDF) (158 pp. 10.3MB to start) - February 2009

Source Control Evaluation Report “Segment 3” Siltronic Property Related to NW Natural “GASCO” Site (PDF) (639 pp. 20.5MB) - February 2009

Groundwater Source Control Treatability Testing (PDF) (31 pp. 528K) - December 2008

Data Summary Report Year 2 Event 1 Long-Term Pilot cap Monitoring (PDF) (8 pp. 481K to start) - December 2008

Groundwater Flow Model and DNAPL Evaluation Supplemental Report (PDF) (37 pp. 4.7MB) - October 2008

DNAPL Removal Pilot Program, NW Natural GASCO Site (PDF) (20 pp. 8.5MB) - October 10, 2008

Annual Data Evaluation Monitoring Report –Year 1 Long–Term Pilot Cap Monitoring (PDF) (9 pp. 259K to start) - September 10, 2008 and May 2008 respectively.

Enhanced Bioremediation Source Control Work Plan - Siltronic Site (PDF) (43 pp. 1.5MB) - May 12, 2008

Data Summary Report Year 1 Event 2 Long-Term Pilot Cap Monitoring (PDF) (7 pp. 479K) - draft undergoing governmental review- April 2008

Revised Long Term Pilot Cap Monitoring Approach (PDF) (40 pp. 4.8MB) draft undergoing governmental review - March 26, 2008

Offshore Investigation Report (PDF) (311 pp. 13MB to start) - February 2008

Data Summary Report Year 1 Event 1 Long-Term Pilot Cap Monitoring (PDF) (6 pp. 546K to start) - February 2008

Siltronic Site: Final Feasibility Study Coordination (PDF) (13 pp. 145K) - December 19, 2007

Groundwater DNAPL Source Control Focused Feasibility Study (PDF) (174 pp. 6.75MB to start) draft undergoing governmental review- November 2007

Focused Feasibility Study (PDF) (140 pp. 3MB) - Siltronic Site - undergoing governmental review- October 23, 2007

Annual Data Evaluation Monitoring Report: Year 0 Long-Term Pilot Cap Monitoring (PDF) (8 pp. 496K to start) draft undergoing governmental review - September 2007.

Phase 2 Step 2 Field Sampling Approach (PDF) (18 pp. 4.7MB to start) August 14, 2007

Siltronic Site Enhanced IN-SITU Bioremediation Pilot Study Report (PDF) (131 pp. 1.8MB) - August 9, 2007

Siltronic Remedial Investigation Workplan (PDF) (65 pp. 12MB to start) July 25, 2007.

Source Control Data Gaps Work Plan (PDF) (55 pp. 2.7MB) - July 2007

Data Summary Report: Year 0 Event 3 Long-Term Pilot Cap Monitoring (PDF) (7 pp. 500K to start) - May 2007.

Groundwater/NAPL Pilot Program Extraction Well and Performance Evaluation Design Report (PDF) (297 pp. 16.5MB) draft undergoing governmental review - May 2007

Siltronic Phase I Report and Phase 2 Sampling_Approach: Source Control Evaluation Draft undergoing government review(PDF) (543 pp. 38.2MB) May 2007.

NW Natural Remedial Investigation Report (PDF) (193 pp. 1.15MB to start) draft undergoing governmental review - April 30, 2007

Siltronic Remedial Investigation Report (PDF) draft undergoing government review (142 pp. 576K) April 16, 2007.

Submittal of Private Aids to Navigation Application Memorandum (PDF) (7 pp. 2MB to start) - March 16, 2007.

Year 0 Round 2 Data Summary Report & Cover Letter (PDF, 22 pp. 286K to start) February 21, 2007.

GASCO/Siltronic Figures: Vinyl Chloride in Transition Zone Water and PAHs/PEC Quotient Data from RI/FS Round 2 Data Summary (PDF) (8 pp. 1MB)- Feb. 6-7, 2007

Request for Regulated Navigation Area Memo (PDF) (7 pp. 1.2MB) - February 2007

Location of GS-06 Offshore Boring Letter (PDF, 4pp. 1.9MB) December 20, 2006.

Addendum to Phase I Field Sampling Approach - December 6, 2006. (PDF, 4pp. 169KB)

GASCO Source Control Data Gaps Evaluation (PDF) (882 pp. 10.5MB) - November 2006.

Siltronic Remedial Investigation Proposal (PDF) (236pp. 22.3MB) - November 17, 2006.

NW Natural Demand for payment of stipulated penalties Administrative Order on Consent for Removal Action (PDF, 2 pp. 179kb) November 16, 2006

Final GASCO Oversight Report November 16, 2006 (PDF, 10pp. 312KB to start)

Institutional Control Memorandum: Gasco Tar Body Removal Post–Construction Controls – Buoys and Signage October 18, 2006 (PDF, 3pp. 1.2MB)

SOP for Hydropunch Sampling (PDF, 3pp. 123KB) October 9, 2006

Draft Year 0 Event 1 Long-Term Pilot Cap Monitoring (Draft Undergoing Agency Review) (PDF, 121pp. 4.64MB to start) October 6, 2006
Year 0 Event 1 Long-Term Pilot Cap Monitoring Summary Report (PDF, 41pp. 644KB) October 6, 2006

Addendum to Phase I Field Sampling Approach - September 29, 2006. (PDF, 7pp. 229KB)

Draft Visual Monitoring Reports Submittal (Draft Undergoing Agency Review) (PDF, 39pp. 1.8MB) - September 20, 2006.

Final Phase 1 - Field Sampling Approach - GASCO Siltronic Groundwater Source Evaluation (PDF, 418pp. 30MB to start) - September 2006 SOP for Hydropunch Sampling (PDF, 3pp. 119KB)

GASCO Diver Reconaissance Survey- Transect 30 Excerpts-Year Zero Event 2. (4 min, 46MB Quicktime) - August 18, 2006. Note: To view this file, you will need the Quicktime Player. Apple provides a free download of this program for Windows.

Enhanced Bioremediation Pilot Study Work Plan - Siltronic Corporation (PDF) (42 pp. 152K to start) - July 28, 2006

Draft GASCO Construction Oversight Report. July 14, 2006. DRAFT undergoing government review. (PDF, 55pp. 2.1 MB to start)

Final Gasco Offshore Sampling Plan. June 21, 2006 (PDF, 425 pp. 41.5 MB to start)

Long Term Monitoring Year 0 Event 1 - Discussion of Path Forward - April 21, 2006 (12 pp. 300 KB pdf)

Revised GASCO Completion Report, TEXT ONLY April 19, 2006 DRAFT undergoing EPA review (556 pp. 32MB pdf)

Long Term Monitoring Year 0 Event 1 – Summary of Field Results and Proposed Alternative Field Methods - April 13, 2006 (8 pp. 165 KB pdf)

GASCO Final Monitoring and Reporting Plan - Post Construction - March 15, 2006 (149 pp. 5.8MB pdf)

GASCO Draft Final Monitoring and Reporting Plan - Post Construction February 6, 2006 (29 pp. 3.3MB pdf to start)

GASCO Visual Monitoring Report January 18, 2006 (9 pp. 500 KB pdf)

GASCO Draft Completion Report January 17, 2006 (undergoing Agency Review, 300 pp MAIN TEXT ONLY, 20 MB pdf)

GASCO Early Action in Review Presentation for Community Advisory Group December 14, 2005 (38 pp. 3.3 MB pdf)

GASCO Weekly Progress Report November 7 - 13 (56 pp. 4 MB pdf) November 16, 2005

GASCO Summary Report - Former MGP Operations and Dense Non-Aqueous Liquid Occurence (PDF) (66 pp. 2.2 MB to start) November 7, 2005

GASCO Weekly Progress Report October 31 - November 6 (39 pp. 1.6 MB pdf) November 8, 2005

GASCO Weekly Progress Report October 24-October 30 (19 pp. 816 KB pdf to start) November 1, 2005

GASCO Weekly Report October 17-23, 2005 (110 pp. 5 MB pdf) - October 25, 2005

GASCO Biological Opinion Amendment - October 20, 2005 (2 pp. 22 KB pdf) - October 20, 2005

GASCO Weekly Report October 10-16, 2005 (137 pp. 5.9 MB pdf) - October 18, 2005

GASCO Post-dredge Sampling Location Map - October 17, 2005 (1 pp. 146 KB pdf) - October 17, 2005

GASCO Monitoring and Reporting Plan - DRAFT undergoing Agency review October 13, 2005 (26 pp. 6 MB pdf to start) - October 13, 2005

GASCO Water Quality Data September 30, 2005 (1 pp. 70 KB pdf) -October 13, 2005

GASCO Water Quality Data September 29, 2005 (2 pp. 150 KB pdf) - October 12, 2005

GASCO Weekly Report through October 9, 2005 (88 pp. 3.6 MB pdf) - October 11, 2005

GASCO Organoclay Design Addendum - October 11, 2005 (5 pp. 1.9 MB pdf) - October 11, 2005

GASCO Biological Opinion - Amendment - October 5, 2005 (3 pp. 700 KB pdf) - October 5, 2005

GASCO Weekly Report through October 2, 2005 (113 pp. 2.93 MB pdf) - October 4, 2005

GASCO Water Quality Sampling Locations (currently sampling WCD1=water quality downstream station #1, WCD4, WCU1) (1 pp. 70 KB pdf) - September 27, 2005

GASCO Water Quality Data September 27, 2005 (2 pp. 10 KB pdf) -September 27, 2005

GASCO Water Quality Data through September 26, 2005 (8 pp. 160 KB pdf) - September 27, 2005

GASCO Water Quality Data through September 23, 2005 (3 pp. 140 KB pdf) - September 23, 2005

GASCO Weekly Report through September 25, 2005 (90 pp. 2.5 MB pdf) - September 25, 2005

GASCO Weekly Report through September 18, 2005 (50 pp. 3.6 MB pdf) - September 18, 2005

GASCO Weekly Report through September 9, 2005 (40 pp 2.8 MB pdf) - September 9, 2005

GASCO Removal Action Biological Opinion (51 pp 315 KB pdf) - August 19, 2005

GASCO Removal Action Project Plan (448 pp 19.2 MB pdf) - July 28, 2005

Siltronic Updated Phase I Characterization Report Summary (99 pp. 1 MB pdf to start) - July 22, 2005

GASCO Water Quality Certification (17 pp 156 KB pdf) - July 26, 2005

Action Memorandum (16 page 105 KB .pdf to start) - June 20, 2005

GASCO Biological Assessment Final Draft (172 pp 11.7 MB pdf) - May 2005

GASCO Public Hearing Transcript on Removal Action May 26, 2005 (27 pp. 161 KB, pdf)

GASCO Engineering Evaluation/Cost Analysis (EE/CA) Public Review Draft (26 pp 800 KB pdf executive summary to start, 238 pp 9.8 MB entire document) - May 13, 2005

Action Memorandum(14 page 60 KB .pdf) - April 28, 2004 Administrative Order on Consent (30 page 116 KB to start .pdf) - April 28, 2004

Statement of Work (13 page 53 KB .pdf)

Report on Supplemental Upland Remedial Investigation Activities Volume 1 - March 11, 2005 (100 pp. 18 MB pdf)

Report on Supplemental Upland Remedial Investigation Activities Volume 2 - Appendices - March 11, 2005 (614 pp. 18 MB pdf)

Revised Baseline Ecological and Human Health Risk Assessment Report (PDF) December 2004. (294 pp. 12MB)

Supplemental Soil Quality Investigation Report- April 2001(208 page 7.23 MB.pdf)

Phase 1 RI Summary Report and Preliminary Analysis of Soil Data Vol 1- October 1998 (59 page 1.45 MB.pdf)

Phase 1 RI Summary Report and Preliminary Analysis of Soil Data Vol. 2 - October 1998 (205 page 6.6 MB.pdf)

Preliminary Analysis of Soil Contamination Data - October 1998 (239 page 8.75 MB.pdf)

Sediment Sample Location Map- September 1998 (1 page 151 KB .pdf)


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