1206 drainage sediment assessment and remedial alternative ... · sediment requiring remediation in...

Memorandum

Date: 3/28/2018 To: Jeff Lux, P.E.

From: David Horne

Subject: 1206 Drainage Sediment Assessment and Remedial Alternative Evaluation

Cimarron Environmental Response Trust (CERT)

As detailed in the July 6, 2017 letter entitled Removal of Burial Area #2 Remediation from Decommissioning Plan (submitted by Environmental Properties Management, LLC [EPM] to the U.S. Nuclear Regulatory Commission [NRC] and the Oklahoma Department of Environmental Quality [DEQ]), groundwater in the Sandstone A formation in and around Former Burial Area #2 (BA2) previously targeted for remediation of uranium in groundwater now appears to comply with the State criteria for unrestricted release. Consequently, the BA2 treated water injection trench (GWI-WU-02) proposed in the 2015 Facility Decommissioning Plan will be removed from the remediation plan for the site. However, based on groundwater samples previously collected from transition zone sediments located downgradient of BA2 (see sample points 1206-HR and MWWA-03 in Attachment 1), groundwater within these sediments do not meet the State criteria and will require remediation. For the purposes of this memorandum and future project deliverables, the 1206 Drainage will be divided into three areas and referenced as follows:

1. 1206 West Drainage 2. 1206 East Drainage 3. 1206 Confluence

These three areas are identified on the figure included as Attachment 2. Due to the limited permeability of 1206 Drainage sediments, and the relatively small volume of sediment requiring remediation in the 1206 West Drainage, the Cimarron Environmental Response Trust (CERT) design team conducted additional characterization of the 1206 West Drainage to obtain data needed to estimate sediment volumes and assess alternative remediation strategies. Excavation and removal was initially identified as a potentially cost-effective alternative for uranium-impacted sediments in the 1206 West Drainage; consequently, the design team elected to conduct additional characterization of the 1206 East Drainage to obtain data needed to assess alternative remediation strategies for this area as well. This Memorandum has been prepared to document the following:

1. Incorporation of 1206 Drainage probe locations and elevations into the project geospatial database

Jeff Lux Environmental Properties Management 3/28/2018

2. Coordinate control and data management – describes procedures used to incorporate site investigation locations, for which standard coordinate and elevation survey data are not available, into the project geospatial database.

3. Development and analysis of a 3-dimensional visualization (3DV) of surface and bedrock topography to estimate 1206 Drainage sediment extents and volumes

4. The proposed 1206 Drainage remediation alternative concept and remediation alternative selection rationale

5. Estimation of the cost impact of the proposed remediation alternative Incorporation of 1206 Drainage Probe Data into Geospatial Database Coordinate and elevation data which had not previously been incorporated into the project geospatial database were compiled for 1206 Drainage probes completed during various phases of site investigation in 1998, 2005, 2014, and 2018. A description of each probe data set is provided below. 1998 – Sub-Area H Post-Remediation Probes Locations for 1206 Drainage probes completed in 1998 were obtained from a figure produced by Kerr-McGee Corporation: Cimarron Facility Phase II – Sub-Area H Post Remediation Drainage Depth Soil Sample Results (1998). This figure was included in Appendix 4 of the 1998 Cimarron Corporation Final Status Survey Report for Subarea H. The process of converting the northing and easting coordinate data from this portable document format (PDF) figure file into digital form is detailed in the December 6, 2017 memorandum entitled CERT Geospatial Coordinate Data Import – Historical Sampling Locations in Surface Drainages Located near Former Burial Areas #2 and #3 (included as Attachment 3). The approximate ground surface elevation of each of these probe locations was based on the LIDAR topographic survey conducted at the site in 2014. The 1998 probe locations are illustrated in Attachment 4. All of the 1998 probe locations were used in the 3DV analysis with the exception of SAH-53. This probe was omitted because it is located outside of the 1206 Drainage. 2005 Probes In 2005, 18 soil probes were completed in the northern segment of the 1206 Drainage, at the confluence of the 1206 West and East Drainages. Northings and eastings for these probes were obtained from a survey conducted in 2005, but the original survey file was inaccessible. However, an existing ArcGIS shapefile that included these probe locations was identified. Notes regarding the source of coordinate data and quality assurance / quality control (QA/QC) were not provided in the shapefile; however, this file was assumed to be the most accurate information


available. Ground surface elevations for each probe location were also provided within the shapefile. The 2005 probe locations are illustrated in Attachment 5. Probes BHWA-13 and BHWA-19 were excluded from the 3DV analysis because they were located outside of the 1206 Drainage, in the alluvial deposits to the north. 2014 Probes In 2014, 15 soil probes were installed within the 1206 Drainage (see Attachment 1). Soil probes were advanced using hand-driven equipment to refusal on bedrock. Probe depths were obtained from data recorded during field investigation activities and cross-sections were prepared using this data. Northings and eastings for these probes were obtained by converting latitude and longitude coordinates obtained from a hand-held global positioning satellite (GPS) device during probe advancement and are assumed to be accurate within approximately 10 feet. However, upon placement of the 206-FR, 1206-G, and 1206-HR probes on the site map, it was determined that the calculated coordinates resulted in probe locations that were outside of the drainages; consequently, these points were relocated based on recommendations from EPM. Ground surface elevations for the probes were estimated using the 2014 LIDAR topographic survey. The 2014 probe locations are illustrated in Attachment 6. The following 2014 1206 Drainage probe locations were excluded from the 3DV analysis for the reasons noted below:

1206-K – adjacent to monitoring well MWWA-09; MWWA-09 data used in lieu of 1206-K data

1206-SB3 – adjacent to multiple soil probes completed in 2018 (see below) 1206-SB6 – located outside the 1206 Drainage (south of 1206 West Drainage) 1206-I – adjacent to multiple soil probes completed in 2018 (see below) 1206-L – located outside the 1206 Drainage (south of 1206 East Drainage)

2018 Soil Probes EPM personnel performed two phases of investigation to collect data in areas not adequately defined during previous investigations. A total of 74 hand-driven probes were advanced within the 1206 West Drainage on January 10, 2018, and 98 probes were advanced within the 1206 East Drainage on January 22, 2018. A detailed description of these investigation activities is presented in the 1206 East Drainage Investigation Memorandum (included as Attachment 7), and the Assessment of Sediment Thickness in 1206 West Drainage Memorandum (included as Attachment 8). As discussed in these memoranda, the probe locations were surveyed in the field using hand measurements referenced to the centerline of the drainage. Northings and eastings for these locations were then calculated using the field measurements and the approximate drainage


centerline estimated from the 2014 LIDAR topographic survey. Ground surface elevations for the probes were estimated using the 2014 LIDAR topographic survey. The 2018 soil probe locations were incorporated into the 3DV analysis and are illustrated in Attachment 9. Additional Data Points The geospatial data set used by the 3DV software application must be of sufficient quantity and distribution to prevent the geostatistical analyses (e.g., kriging) from generating unrepresentative topographic surfaces and volume estimates. Due to the size of the 1206 Drainage 3DV domain and a lack of geospatial data in specific areas, 129 data points were added to constrain the 3DV model. These ‘constraining points’ consisted of the following:

1. 14 points established along the center of the 1206 East Drainage of the drainage. The 2014 LIDAR topographic survey was used to locate the center of the drainage and estimate ground surface elevations for these data points. These points are denoted as ‘Middle_of_channel’ in the 3DV figure included as Attachment 10. As shown on the figure, these points are limited to segments of the 1206 East Drainage located between the 2018 soil probes and the 1998 soil probes, and between the 1998 soil probes and historical probes to the north.

2. 14 points collocated (in the xy-dimension) with ‘Middle_of_channel’ locations described in #1 above. These points are located at the sediment/bedrock interface elevation, estimated based on data obtained from the nearest soil probe completed during site investigation efforts (see above). Incorporation of these data points resulted a smoother, more realistic depiction of bedrock topography within the 1206 East Drainage. These are the only constraining points that included estimated elevations not based upon the 2014 LIDAR topographic survey.

3. 73 points established to more accurately depict the lateral drainage boundaries at ground surface (i.e., the sediment/bedrock interface along the drainage slopes). The locations of these points were selected based on topography provided by the 2014 LIDAR survey; sharp increases in elevation were used to locate drainage edges. Following initial selection of these data points, the locations were confirmed by field personal familiar with the physical attributes of the 1206 Drainage. Northings, eastings, and ground surface elevations for these points were also obtained from the 2014 LIDAR topographic survey. These points are denoted as ‘Bedrock’ locations in the 3DV plan view figure included as Attachment 11.

4. 28 points of known surface elevation established to more accurately represent the ground surface between the 1206 West Drainage and 1206 East Drainage within the 3DV


domain. Without an accurate ground surface depiction between the two drainages, the 3DV kriging analysis would lack boundaries, resulting in inaccurate sediment volume calculations. The northings, eastings, and elevations of these points were obtained from the 2014 LIDAR topographic survey. These points are denoted ‘T’ locations in the 3DV plan view figure included as Attachment 12.

Coordinate Control and Data Management Coordinate control across the different data sets was accomplished using ArcMap version 10.4 and AutoCAD version 2017. The 1998 soil probe coordinates were converted from a local coordinate system into the Oklahoma State Plane North coordinate system as discussed in the memorandum referenced above. The 2005 probe coordinates were previously converted to a shapefile referenced to the Oklahoma State Plane North coordinate system and the 2014 probe locations, originally surveyed to latitude/longitude coordinates using a mobile GPS device, were converted to the Oklahoma State Plane North coordinates using an online application (http://www.earthpoint.us/StatePlane.aspx) and digitized as a shapefile (2014 Design Investigation Borings.shp). The 2018 probe locations were located in AutoCad by first approximating the drainage centerline (assumed to follow the topographic low depicted in 2014 LIDAR topographic survey) used as a reference for field measurements. The field measurements were then used to plot probe locations in AutoCad and obtain the Oklahoma State Plane North coordinates. The northings, eastings, ground surface elevations, and bedrock elevations for all probes and constraining points were managed within an MS Excel® data workbook for subsequent input to the 3DV software application. The following QA/QC tasks were completed in coordination with this effort:

1. 2018 probe locations plotted in AutoCAD were reviewed with field personal present during probe installation. The surveyed locations were compared against aerial images and topographic contours and adjusted as necessary, with input from field personnel, to achieve the most accurate locations possible.

2. Constraining points representing the edges of sediment deposits were reviewed with field personal present during probe installation. The surveyed locations were compared against aerial images and topographic contours and adjusted as necessary, with input from field personnel, to achieve the most accurate locations possible.

3. Data entered into the data workbook were reviewed to confirm that coordinates and elevations were correctly transcribed from previous sources (i.e., 1998, 2005, 2014 data sets).


4. Data entered into the data workbook were reviewed to confirm that northing and eastings were transcribed correctly from the AutoCAD file.

5. Data entered into the data workbook were reviewed to confirm that elevations obtained from the 2014 LIDAR topographic survey were correctly transcribed from the AutoCAD file.

Development and Analysis of 3D Visualization 3DV Construction A 3DV of sediment, bedrock, and ground surface topography in the 1206 Drainage and surrounding areas was constructed using the Earth Volumetric Studio® (EVS) software application. Although three physical surfaces (bedrock, ground, and sediment) are included in the 3DV, they are represented by only two topographic surfaces. This can be explained by the manner in which the aforementioned data sets were entered into EVS and used in the geostatistical analysis:

For probes and constraining points located within the drainages, the shallowest elevation represented the ground surface and top of sediment. The deepest elevation represented the top of bedrock.

Elevations for constraining points located at the sediment/bedrock interface along the drainage slopes represented top of bedrock.

Elevations for constraining points located between the eastern and western drainages represented the ground surface, typically a foot or more above top of bedrock.

Within the EVS, the drainage sediment / ground surface elevation data were contoured as one topographic surface. The top of bedrock (within the 1206 Drainage) elevation data and ground surface (outside of the 1206 Drainage) elevation data were then contoured together to form a single topographic surface that underlaid and constrained the sediment surface. The domain for each surface was determined by the data and the extent of the drainages. The EVS application was used to perform geostatistical evaluation of the sediment material using a kriging estimation method consisting of a spherical variogram and anisotropy with a range of 549, a sill of 2.14, and a nugget of 0. Geostatistical evaluation of the bedrock/ground surface was performed using the Natural Neighbors estimation method. Images of the 3DV are presented in figures included in Attachments 10 through 12. In addition, a 3DV image of the drainage sediment ‘body’ created by the EVS geostatistical evaluation is presented in a figure included as Attachment 13. A plan view depiction of the sediment body is provided in Attachment 14. 3DV Interpretations


The EVS application was used to perform geostatistical calculations to estimate the volume of sediment within the 1206 Drainage. The 1206 Drainage contains a total of approximately 7,589 cubic yards of sediment, comprised of the following:

1,970 cubic yards of sediment in the 1206 East Drainage, located downgradient of Former Burial Area #3 (BA3);

131 cubic yards of sediment in the 1206 West Drainage, located downgradient of and BA2; and,

5,488 cubic yards of sediment in the 1206 Confluence. The boundaries and calculated sediment volumes for all three 1206 Drainage areas are presented on the figures included in Attachments 13 and 14. The northern boundary of the 1206 East Drainage is defined by probe BHWA-15 (see Attachment 5) and the northern boundary of the 1206 West Drainage is defined by the northern line of 2018 soil probes (Probe-01 through Probe-07) [see Attachment 9]. Soil probes were advanced through standing water or saturated sediment in the majority of probe locations in both the 1206 East and West Drainages. Consequently, all drainage sediment was functionally classified as saturated, and an estimation of saturated versus unsaturated sediment thickness/volume was not considered relevant to the evaluation of remediation alternatives. QA/QC The 3DV was subjected to a QA/QC review process that included confirmation of the following within the EVS database:

1. The correct input data were uploaded into the EVS software application; 2. The EVS software 3DV model framework was correctly created; 3. The most appropriate geostatistical estimation methods were used (e.g., kriging, Natural

Neighbors, spline, etc.); and, 4. The correct EVS software 3DV model framework parameters were selected.

1206 Drainage Remediation Alternative Evaluation Burns & McDonnell considered multiple remediation alternatives for the 1206 Drainage in an effort to reduce cost and improve certainty of performance. Alternatives considered included:

Treated water injection within the 1206 West Drainage, as originally planned for BA2 and 1206 East Drainage;


Enhanced treated water injection within the 1206 East Drainage, to increase hydraulic gradient and flux beyond that provided by injection trench GWI-WU-01;

Groundwater extraction, via collection trenches, with 1206 East and West Drainages; and,

Sediment excavation and removal. Due to the limited permeability of 1206 Drainage sediments and the relatively small depth and volume of sediment requiring remediation in the 1206 East and West Drainages, the treated water injection and groundwater extraction alternatives were eliminated for 1206 East and West Drainages. In addition, the fact that 1206 Drainage sediments are in compliance with unrestricted NRC license release criteria increased the favorability and feasibility of the excavation and removal alternative. Consequently, the design team proceed with developing a design concept and cost estimate for an alternative that included excavation and removal of the relatively thin sediment deposits within the 1206 East and West Drainages. This alternative would also include in situ remediation of 1206 Confluence sediments via treated water injection and groundwater extraction. 1206 Drainage Remediation Alternative Concept As indicated above, Burns & McDonnell developed an alternative remediation approach for the 1206 Drainage consisting of sediment excavation, treated water injection, and groundwater extraction. This alternative is illustrated on the figure included as Attachment 15 and a detailed description of the alternative is provided below.

1. Clearing and grubbing of the 1206 East Drainage will be performed to provide access for the excavation and construction activities described below.

2. Sediments within the 1206 West Drainage will be excavated from the southern extent of the drainage to the point at which sediment becomes approximately 6 feet thick (estimated to be approximately 100 feet southwest of monitor well MWWA-03). Since the only groundwater exceeding either the State or NRC criteria is contained within the sediment, the removal of this sediment effectively remediates groundwater in the 1206 West Drainage.

3. Sediments within the 1206 East Drainage will be excavated from monitor well 1359 to the point at which sediment becomes approximately 6 feet thick (estimated to be approximately 110 feet southeast of monitor well MWWA-09).

4. Sediments excavated from the 1206 East and West Drainages will be transported to the Uranium Pond #1 and #2 (UP1 and UP2) remediation areas. At UP1 and UP2, the sediments will be mixed with spoils generated during the excavation of full-scale treated


water injection trenches to minimize the potential for potentially contaminated water within the sediment materials to migrate. The mixed sediment/spoils will be spread on the ground in the UP2 Material Stockpile Area established during the 2017 Pilot Test, capped with topsoil, and stabilized with seed, mulch, and fertilizer. The soils will remain outside of the 100-year floodplain.

5. A perforated pipe will be installed along the 1206 East Drainage centerline to convey natural drainage and discharges resulting from operation of injection trenches GWI-WU-01 and GWI-UP1-01 through GWI-UP1-06. The pipe will be installed on granular bedding material placed directly on the bedrock surface and covered with a protective layer of aggregate appropriately sized to accommodate stormwater flow velocities. Perpendicular laterals will be installed at the northern terminus of the drainage pipe to facilitate the infiltration of water into the remaining transition zone sediments in the 1206 Confluence. Water migrating through these sediments will be captured by extraction trench GETR-WAA-01.

6. The location and orientation of GETR-WAA-01 will be optimized. The trench has been repositioned to the south as needed to avoid influencing hydraulic conditions in the floodplain alluvium and to maximize recover of groundwater within transition zone sediments. Additional trench optimization will be conducted during finalization of the revised 60% remediation design.

1206 Drainage Remediation Alternative Cost Estimation and Selection Rationale Using the estimated sediment volumes provided by the 3DV analysis detailed above, Burns & McDonnell obtained preliminary budgetary pricing for excavation, relocation, and stabilization of 1206 Drainage sediments. Based on this pricing data, the estimated budgetary cost for the 1206 Drainage remediation alternative described above and depicted in the sketch included as Attachment 15 is on the order of $210,000. The alternative 1206 Drainage remediation approach described above provides the following benefits:

1. The alternative eliminates the cost of installing and operating GWI-WU-02 and associated water conveyance piping, controls, instrumentation, etc. In 2015, the cost of installing this remediation infrastructure was estimated to be $73,000. Consequently, the cost of the alternative described above, which addresses both 1206 East and West Drainages, would be significantly offset by the elimination of the BA2 / 1206 West injection remedy.


2. The alternative achieves immediate remediation of the 1206 East and West Drainages by removing material containing groundwater that may be in excess of remediation criteria;

3. The alternative will accelerate remediation of groundwater within 1206 Confluence transition zone sediments by reducing the length of the water migration flow path between GWI-WU-01 and the 1206 Confluence sediments. Removing sediments from the 1206 East and West Drainages should also increase the rate and volume of natural drainage through the 1206 Confluence sediments.

4. The alternative greatly reduces uncertainty related to the remediation of groundwater in the sediment.

DCH/dch


Attachments: Attachment 1 – 1206 Drainage Groundwater Concentrations Attachment 2 – 1206 Drainage Areas

Attachment 3 – CERT Geospatial Coordinate Data Import Memorandum Attachment 4 – 1998 Probe Locations Attachment 5 – 2005 Probe Locations Attachment 6 – 2014 Probe Locations

Attachment 7 – 1206 West Drainage Investigation Memorandum Attachment 8 – 1206 East Drainage Investigation Memorandum Attachment 9 – 2018 Probe Locations Attachment 10 – Middle of Channel Constraining Locations Attachment 11 – Bedrock Constraining Locations Attachment 12 – Terrain Constraining Locations Attachment 13 – 1206 Drainage Sediment Volume Estimates (3D View) Attachment 14 – 1206 Drainage Sediment Volume Estimates (Plan View) Attachment 15 – Sketch - Remedial Alternative for the 1206 Drainage

Attachment 1 – 1206 Drainage Groundwater Concentrations

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1206-CR

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1206-JR

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1206-FR1206-SB6

1206-SB3

MWWA-09

MWWA-03

T-74

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Attachment 11206 DRAINAGEGROUNDWATER

CONCENTRATIONSCIMARRON SITE, OKLAHOMA

272 ug/L272 ug/L

91 ug/L91 ug/L

156 ug/L156 ug/L

127 ug/L127 ug/L145 ug/L145 ug/L

586 ug/L586 ug/L

84.4 ug/L84.4 ug/L

206 ug/L206 ug/L

8 ug/L8 ug/L

14 ug/L14 ug/L

3 ug/L3 ug/L

3 ug/L3 ug/L125 ug/L125 ug/L

2 ug/L2 ug/L


875 ug/L875 ug/L


14 ug/L14 ug/L

72 ug/L72 ug/L

3 ug/L3 ug/L

22 ug/L22 ug/L

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M MONITORING WELL IN SANDSTONE Cug/L - MICROGRAMS PER LITER(GROUNDWATER URANIUM CONCENTRA-TION)

MONITOR WELL GROUNDWATER CON-CENTRATIONS CALCULATED FROM 2011 THROUGH 2ND QUARTER 2016 DATA

2014 1206 DRAINAGE PROBES

Attachment 2 – 1206 Drainage Areas

NOTES:1) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).2) AERIAL SURFACE BASED ON 2014 LIDAR SURVEY.3) AERIAL IMAGE TAKEN FROM ARCMAP (ESRI, DIGITALGLOBE, GEOEYE, EARTHSTAR, GEOGRAPHICS, CNES/AIRBUS DS, USDA, USGA, AERO-GRID, IGN, AND THE GIS USER COMMUNITY).

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Attachment 21206 DRAINAGE AREAS

CIMARRON SITE, OKLAHOMA

1206 CONFLUENCE

1206 DRAINAGE EAST

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Attachment 3 – CERT Geospatial Coordinate Data Import Memorandum

Memorandum

Date: 12/06/17 To: Cimarron Environmental Response Trust (CERT) Design Team

From: David Horne

Subject: CERT Geospatial Coordinate Data Import – Historical Sampling Locations in Surface

Drainages Located near Former Burial Areas #2 and #3

This Memorandum has been prepared to document the incorporation of coordinate data for historical soil boring and sampling locations originally completed by Cimarron Corporation. Incorporation of this data was required to complete an evaluation of saturated overburden thickness and extent within the surface drainages located near Former Burial Areas #2 and #3 at the Cimarron Remediation Site. The following revisions and additions to the Site geospatial database were conducted in accordance with the December 22, 2016 project memorandum entitled: CERT Groundwater Remediation Project – Review of Geospatial Coordinate Systems and Data Management Practices. Locations of Subarea H Final Status Survey (FSS) soil borings, completed in 1998 and surveyed using a local coordinate system, required incorporation into the current project geospatial database developed from surveys referenced to the Oklahoma State Plane North coordinate system. The Subarea H boring locations could only be obtained from scanned copies of historical Cimarron Corporation figures included in the Final Status Survey Report for Subarea H1. Images of these historical site figures were imported into ArcGIS and site features, including building corners, common to both the historical figures and surveys incorporated into the current GIS database were used to align the historical imagery overlay and approximate Subarea H boring location coordinates in the State Plane system. The following historical figures were used in the data import and coordinate conversion process:

1. Cimarron Facility Phase II – Sub-Area H Post Remediation Drainage Soil Sample Results (1998) Soil Sample Aliquot: Surface (0-6”)

2. Cimarron Facility Phase II – Sub-Area H Post Remediation Drainage Depth Soil Sample Results (1998)

The corners of the Plutonium Building and the Warehouse Building #4 were first used to align the Soil Sample Aliquot: Surface (0-6”) figure image with the site survey in ArcGIS. While this achieved alignment the southwestern portion of the figure, site feature location discrepancies between the historical figure image and the underlying site survey were recognized in the northeastern portion of the figure. These discrepancies were caused by image irregularities resulting from printing and scanning of the historical figure. To address this, a fence corner, present on both the historical figure and the ArcGIS basemap (consisting of a geo-referenced

1 Cimarron Corporation. Final Status Survey Report for Subarea H. November, 1998.

12/06/17 Page 2

Memorandum (cont’d)

aerial photo), was used to align the northeastern portion of the figure. To assess the potential for discrepancies between the geo-referenced aerial basemap and site survey, surveyed locations of monitor wells located near the fence corner were compared (via image overlay) to corresponding monitor well concrete pads shown in the basemap aerial imagery. The well pads generally plotted 2 feet north of the surveyed well locations. Consequently, the fence corner included on the historical figure was placed approximately 2 feet south of the location shown in the basemap aerial imagery. Using six fit points – five building corners and one fence corner – ArcGIS rotated, scaled, and appropriately warped the historical figure image using a 1st order polynomial (affine) transformation. An imported image of the second historical figure referenced above was then aligned with the first using four fit points located on original site survey coordinate lines present in both figures. Subarea H soil boring location coordinates were then taken from the approximate center point of the boring symbols shown on both historical figures. From the methods described above, it is reasonable to assume that the boring locations and site features imported from the scanned Cimarron Corporation figures are positioned geospatially within approximately 1 meter of the actual locations in the Oklahoma State Plane North coordinate system. Network file paths for the files referenced herein are as follows:

Historical Site Figures: \\bmcd\dfs\Clients\ENS\CERT\_ClientInfo\Sites\Database\Geospatial\Maps & Dwgs\ArcGIS\BMCD_Files\Arcdocs\2017\2017 Drainage Way Docs\APP 4 MAP 98POAHDSSS-0 (2 of 10).pdf

\\bmcd\dfs\Clients\ENS\CERT\_ClientInfo\Sites\Database\Geospatial\Maps & Dwgs\ArcGIS\BMCD_Files\Arcdocs\2017\2017 Drainage Way Docs\APP 4 MAP 98POAHDDSS (1 of 10 ).pdf

ArcGIS Shapefile: \\bmcd\dfs\Clients\ENS\CERT\_ClientInfo\Sites\Database\Geospatial\Maps & Dwgs\ArcGIS\BMCD_Files\Arcdocs\2017\2017 Drainage Way Docs\CERT Drainage Way.mxd

Network file paths are included to document file location for future Burns & McDonnell reference, and are not relevant to Environmental Properties Management, LLC (EPM) or regulatory agency personnel. DCH/dch

Attachment 4 – 1998 Probe Locations

Attachment 41998 PROBE LOCATIONS


NOTES:1) SAH LOCATIONS (PINK SPHERES) REPRESENT SOIL PROBES CONDUCTED IN 1998.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).

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Attachment 52005 PROBE OCATIONS


NOTES:1) BHWA LOCATIONS (TEAL SPHERES) REPRESENT SOIL PROBES CONDUCTED IN 2005.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).

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NOTES:1) 1206 LOCATIONS (BROWN SPHERES) REPRESENT SOIL PROBES CONDUCTED IN 2014.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).4) 1300 LOCATIONS (BLUE SPHERES WITH WHITE CENTERS) REPRESENT MONITOR WELLS.20

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Attachment 7 – 1206 West Drainage Investigation Memorandum

Date: January 14, 2018 To: John Hesemann

From: Jeff Lux

Subject: Assessment of Sediment Thickness in 1206 West Drainage

On January 10, 2018, a 4-foot soil probe was used to determine the thickness of sediment in the 1206 West drainage. The probe was a tapered steel rod with a T-handle at the top. The intention of the test was to provide data which can be used to estimate the volume of sediment in this portion of the 1206 Drainage channel. Preparatory Work In November and December 2017, Remediation Services, Incorporated (RSI) cleared vegetation from the western portion of the 1206 drainage. After removing the vegetation, RSI graded the area, partially backfilling the drainage channel. RSI installed erosion control fabric in the channel to minimize sediment transport and applied hydro-mulch to the entire disturbed area. Seepage from the sandstone that formed the sides of the drainage collects in the restored channel, and the resulting drainage “stream” does not always flow in the center of the drainage channel. Pin flags were placed in the topographically low point of the channel, which was not always the center of the drainage. Field Assessment The end of a 300-foot tape was fastened to the lock on the protective casing for Monitor Well MWWA-03, and the tape was extended southward toward the centerline of the drainage way (see image “1 – SSE From MWWA-03.jpg”). The first 110 feet of the tape spanned a relatively broad, fairly level area, which is at least three feet in elevation higher than the floodplain alluvium. This area is considered to be within the transition zone, located between the floodplain alluvium and drainage sediment; there was no clear evidence of a “channel” in this area. Starting 110 feet south of MWWA-03, orange pin flags were placed at 10-foot intervals in the approximate center of the “stream” in the drainage. The following images show the placement of pin flags and the configuration of the channel centerline: • “2 – S From 110 Feet.jpg” • “3 – SSE From 170 Feet.jpg” • “4 – S From 210 Feet.jpg”

The soil probe was advanced near each pin flag and at 2-foot (lateral) intervals from the pin flag in a direction perpendicular to the tape. At times, a steep bank was immediately adjacent to the probe location, and at some locations, the furthest location that was probed was on the sloping soil bank of the channel.

January 14, 2018

• From 110 feet to 170 feet the drainage was fairly level (see images “2 – S From 110

Feet.jpg”). • From 170 feet to 220 feet, the channel sloped upward (see image “3 – SSE From 170

Feet.jpg”). • From 220 feet to 290 feet, the channel was fairly level (see image “4 – S From 210

Feet.jpg”). • Beyond 290 feet, the channel was very narrow, with rocky sides, a rocky bottom, and very

little soil. The last pin flag that can be seen in image “4 – S From 210 Feet.jpg” was set at 290 feet.

• No attempt was made to probe the channel past the 290-foot pin flag.

The four images referenced in this section are presented in Attachment A. Results A spreadsheet entitled, “1206 West Sediment Thickness” was generated to document the thickness of soil at each probe location. Blue highlighting and the letter “B” in cells indicates that the boundary of the drainage channel had been reached by that distance from the center pin flag. The spreadsheet is presented in Attachment B. Attachments cc: Jeff Binder

Eric Dulle

January 14, 2018

ATTACHMENT A SITE IMAGES

View looking south-southeastfrom Monitor Well MWWA-03.

View looking south from 110'from Monitor Well MWWA-03.

View looking south-southeast from110' from Monitor Well MWWA-03.

View looking south from 210'from Monitor Well MWWA-03.

January 14, 2018

ATTACHMENT B 1206 WEST DRAINAGE SEDIMENT THICKNESS DATA

Cimarron Environmental Response Trust1206 West Drainage Sediment Thickness (feet)

Center

6' 4' 2' 0' 2' 4' 6'

110' B 1.5 2.0 3.75 3.5 3.5 B

120' B 1.0 1.5 1.5 2.0 B

130' B 1.75 1.5 2.25 2.75 1.5 B

140' B 3.0 2.0 1.75 1.75 2.0 B

150' 3.0 2.5 2.5 2.5 2.25 3.0 B

160' B 1.5 3.5 3.0 2.0 2.0 B

170' B 3.0 3.0 3.75 4.0 3.0 B

180' B 3.0 3.0 3.0 2.0 2.0 B

190' B 1.25 1.25 1.25 1.25 1.0 B

200' B 0.75 0.75 1.0 1.25 B

210' B 2.25 2.5 2.75 2.5 1.0 B

220' B 1.25 1.5 1.5 B

230' B 1.5 2.25 2.0 B

240' B 1.5 1.0 1.0 B

250' B 0.5 0.5 B

260' B 0.5 0.75 B

270' B 1.0 1.0 B

280' B 1.0 1.0 1.0 B

290' B 0.75 1.0 B

From 290' - 350', the channel is < 4' wide with very little sediment.

From MWWA-03 to 110' there's no defined channel.

LocationWest of CenterEast of Centerline

Attachment 8 – 1206 East Drainage Investigation Memorandum

Memorandum

Date: January 23, 2018 To: John Hesemann, David Horne

From: Jeff Lux, EPM and Dane Kaylor, ENERCON Services

Subject: Assessment of Sediment Thickness in 1206 East Drainage On January 22, 2018, a 4-foot soil probe was used to determine the thickness of sediment in the eastern 1206 drainage. The probe was a tapered steel rod with a T-handle at the top. The intention of this test is to provide data which can be used to estimate the volume of sediment in this drainage channel. A stake was placed in the center line of the channel approximately 50 feet west of monitoring well 1360 (Image 1 – West from 1360). From this location, a 300-foot tape was extended along the center line of the channel. The soil probe was advanced near the center-line and at 2-foot distances in a direction perpendicular to the tape. A spreadsheet entitled, “1206 East Sediment Thickness” was generated to document the thickness of soil at each location The first 120 feet of line reached across a very narrow section of the drainage channel which had little (0 to 4 inches) soil covering the exposed bedrock. From 120 to 130 feet a large pool and waterfall prevented accurate soil probing (Image 2 – South from 230’ Mark). Seepage from the sandstone that formed the sides of the drainage does not always flow in the center of the drainage channel. The flags were placed in the topographically low point of the channel, which was not always the center of the drainage (Image 3 – North from 200’ Mark). From 130 feet to 160 feet the channel maintained a regular width from 12 to 15 feet with a well-defined, rocky bank. At times, a steep bank was immediately adjacent to the probe location, and at some locations, the furthest location was probed on the sloping soil bank of the channel. Soil thicknesses ranged from 1.5 to 2.5 feet in the center and 0.25 to 3.0 feet nearer the bank. From 160 to 230 feet the channel widened from 16 to 20 feet with a very well defined, steep bank to the east and a more sloping bank to the west (Image 4 – South from 230’ Mark). Soil thickness increased in this interval, ranging from 2 feet to 4 feet. From 230 to 280 feet soil thickness continue to increase while the channel broadened. Probing was ceased after consecutive 4-foot depths were recorded as locations reached 280 feet. Channel width along this interval was more than 20 feet and the bank became less defined (Image 5 – North from 250’ Mark) and included a large “quarry” area to the west of the 300-foot mark (Image 6 – North from 300’ Mark and Image 7 – NE from 300’ Mark towards Quarry).

January 23, 2018 Page 2


Image 1: West from Monitoring Well 1360.



Image 2: South from 230’ mark towards pool and waterfall.



Image 3: North from 200’ mark along center-line. Small tributary running NE from main drainage.

Image 4: South from the 230’ mark. Steep bank to the East and sloped bank to the West.



Image 5: North from 250’. Channel begins to widen while becomes less defined. End of interval at 300’ in the distance.

Image 6: North from 300’ Mark. Channel loses definition and is covered in grasses.



Image 7: NE from 300’ Mark towards quarried location and fallen timber.

Cimarron Environmental Response Trust1206 East Drainage Sediment Thickness (feet)

Center10' 8' 6' 4' 2' 0' 2' 4' 6' 8' 10'

102030405060708090100110120130 bank 0.25 1.75 1.50 0.00 1.00 bank140 bank 1.00 2.00 1.50 1.25 bank150 bank 3.00 3.00 2.25 2.00 0.50 0.25 bank160 bank 1.75 1.75 1.75 2.50 0.25 0.25 bank170 bank 1.50 2.50 2.00 2.25 1.75 bank180 bank 4.00 2.25 1.75 2.50 2.25 2.25 2.75 bank190 bank 4.00 4.00 2.25 2.50 1.75 3.25 bank200 bank 4.00 4.00 2.50 2.00 2.00 2.00 2.75 bank210 bank 4.00 2.75 2.75 2.25 2.25 2.75 bank220 bank 4.00 2.75 3.00 2.75 2.00 2.00 3.50 bank230 bank 3.25 3.00 1.75 3.00 3.25 bank240 bank 2.00 2.25 3.00 3.50 4.00 bank250 bank 3.00 3.00 2.75 2.75 1.75 0.50 2.75 bank260 bank 4.00 3.50 3.50 3.00 3.00 4.00 4.00 bank270 bank 4.00 4.00 4.00 3.50 3.75 4.00 4.00 bank280 bank 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 bank290300

LocationEast of Center LineWest of Centerline

No further probing

no access

Narrow channel with exposed bedrock, waterfall and large pond to 122'

Very tight channel; minimal coverage 0 to 6" overlaying hard rock base. Channel width approximately 8 to 10'

0' is ~50' due West of Monitoring Well 1360



NOTES:1) PROBE LOCATIONS (ORANGE SPHERES) REPRESENT SOIL PROBES CONDUCTED IN 2018.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).4) 1300 LOCATIONS (BLUE SPHERES) REPRESENT MONITOR WELLS.20

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Attachment 10 – Middle of Channel Constraining Locations

Attachment 10MIDDLE OF CHANNEL

CONSTRAINING LOCATIONSCIMARRON SITE, OKLAHOMA

NOTES:1) MIDDLE OF CHANNEL CONSTRAINT LOCATIONS REPRESENTED AS BLUE SPHERES.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) RED AND GREEN SPHERES REPRESENT ADDITIONAL MODEL CONSTRAINING LOCATIONS (SEE ATTACHMENTS 11 AND 12).4) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).5) 1300 LOCATIONS (BLUE SPHERES WITH WHITE CENTERS) REPRESENT MONITOR WELLS.

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Attachment 11 – Bedrock Constraining Locations

Attachment 11BEDROCK

CONSTRAINING LOCATIONSCIMARRON SITE, OKLAHOMA

NOTES:1) BEDROCK CONSTRAINT LOCATIONS REPRESENTED AS RED SPHERES.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) BLUE AND GREEN SPHERES REPRESENT ADDITIONAL MODEL CONSTRAINING LOCATIONS (SEE ATTACHMENTS 10 AND 12).4) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).5) 1300 LOCATIONS (BLUE SPHERES WITH WHITE CENTERS) REPRESENT MONITOR WELLS.

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Attachment 12 – T Constraining Locations

Attachment 12TERRAIN CONSTRAINING

LOCATIONSCIMARRON SITE, OKLAHOMA

NOTES:1) TERRAIN CONSTRAINT LOCATIONS REPRESENTED AS GREEN SPHERES.2) BROWN SURFACE REPRESENTS MODEL EXTENTS.3) RED AND BLUE SPHERES REPRESENT ADDITIONAL MODEL CONSTRAINING LOCATIONS (SEE ATTACHMENTS 10 AND 11).4) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).5) 1300 LOCATIONS (BLUE SPHERES WITH WHITE CENTERS) REPRESENT MONITOR WELLS.

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Attachment 13 – 1206 Drainage Sediment Volume Estimates (3D View)

Attachment 133D SEDIMENT VOLUME


NOTES:1) 4X VERTICAL EXAGGERATION.2) PINK, TEAL, BROWN, AND ORANGE SPHERES REPRESENT SOIL BORINGS AND PROBES CONDUCTED IN 1998, 2005, 2014, AND 2018, RESPECTIVELY.3) BLUE, RED, AND GREEN SPHERES REPRESENT MODEL CONSTRAINING LOCATIONS (SEE ATTACHMENTS 10, 11, AND 12).4) BLUE COLUMNS REPRESENT MONITORING WELL SCREENS.5) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).6) AERIAL SURFACE BASED ON 2014 LIDAR SURVEY.7) AERIAL IMAGE TAKEN FROM ARCMAP (ESRI, DIGITALGLOBE, GEOEYE, EARTHSTAR, GEOGRAPHICS, CNES/AIRBUS DS, USDA, USGA, AEROGRID, IGN, AND THE GIS USER COMMUNITY).

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Attachment 14 – 1206 Drainage Sediment Volume Estimates (Plan View)

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Attachment 141206 DRAINAGEWAY

SOIL VOLUME ESTIMATESCIMARRON SITE, OKLAHOMA

NOTES:1) 4X VERTICAL EXAGGERATION.2) PINK, TEAL, BROWN, AND ORANGE SPHERES REPRESENT SOIL BORINGS AND PROBES CONDUCTED IN 1998, 2005, 2014, AND 2018, RESPECTIVELY.3) BLUE, RED, AND GREEN SPHERES REPRESENT MODEL CONSTRAINING LOCATIONS (SEE ATTACHMENTS 10, 11, AND 12).4) 1300 LOCATIONS (BLUE SPHERES WITH WHITE CENTERS) REPRESENT MONITOR WELLS.5) GREEN, YELLOW, AND BLUE SURFACE REPRESENTS WEST DRAINAGE, EAST DRAINAGE, CONFLUENCE (RESPECTIVELY).6) AERIAL SURFACE BASED ON 2014 LIDAR SURVEY.7) AERIAL IMAGE TAKEN FROM ARCMAP (ESRI, DIGITALGLOBE, GEOEYE, EARTHSTAR, GEOGRAPHICS, CNES/AIRBUS DS, USDA, USGA, AEROGRID, IGN, AND THE GIS USER COMMUNITY).

Attachment 15 – Sketch - Remedial Alternative for the 1206 Drainage

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Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID,IGN, and the GIS User Community

AERIAL PHOTO - 2010 / MAP PRODUCED - 3/29/2018COORDINATES : (NAD 83) STATE PLANE OKLAHOMA NORTH FEETSource: ESRI and Burns & McDonnell Engineering.

DATE :

±0 100 20050Feet

ATTACHMENT 15REMEDIAL ALTERNATIVE FOR THE

1206 DRAINAGE - SKETCHCIMARRON SITE, OKLAHOMA

0

LegendINJECTION WELL

M MONITORING WELL IN TRANSITION ZONE

M MONITORING WELL IN ALLUVIUM

M MONITORING WELL IN SANDSTONE A

M MONITORING WELL IN SANDSTONE B

M MONITORING WELL IN SANDSTONE C

5-FOOT CONTOUR

PROPOSED GW EXTRACTION TRENCH

PROPOSED GW INJECTION TRENCH

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OPTIMIZE GETR-WAA-01 LOCATION/ORIENTATION.MOVE TRENCH SOUTH AS NEEDED TO AVOIDINFLUENCING ALLUVIUM AND PLACE TRENCH WITHINTRANSITION ZONE SEDIMENTS. ACTUAL LOCATIONWILL BE DETERMINED DURING 60% DESIGN REVISIONSAND PRESENTED IN REVISED DECOMMISSIONINGPLAN.

PERFORATED PIPE TO CONVEYNATURAL DRAINAGE AND DISCHARGESASSOCIATED WITH GWI-WU-01 AND UP1INJECTION TRENCHES

EXCAVATE DRAINAGE SEDIMENT.EXCAVATE NORTH UNTIL SEDIMENTSBECOME APPROXIMATELY 6-FEETTHICK.

GWI-WU-01

EXCAVATE DRAINAGE SEDIMENT.EXCAVATE NORTH UNTIL SEDIMENTSBECOME APPROXIMATELY 6-FEETTHICK.

1206 drainage sediment assessment and remedial alternative ... · sediment requiring remediation in...

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