Utility_Locating_Services.pdf

VIA EMAIL: janis.cooper@cityarchriver.org

February 3, 2014 J017065.14

Ms. Janis Cooper City Arch River 2015 Foundation Gateway Tower, Suite 700 One South Memorial Drive St. Louis, Missouri 63102

Re: Utility Locating Services

CAR 2015

Jefferson National Expansion Memorial St. Louis, Missouri

Dear Ms. Cooper:

Geotechnology, Inc. has completed utility locating services for the Jefferson National Expansion Memorial Project CAR 2015 located in St. Louis, Missouri. The project was performed in general accordance with proposal number P017065.14 dated November 12, 2013. Utility locating was performed at eleven locations.

Utility drawings provided by Michael Van Valkenburgh Associates, Inc. (MVVA) were reviewed. In general, site utilities included electric, fiber optic, steam, and water lines. An electric duct bank generally trends northwest-southeast at a location east of the intersection between Pine Street and Interstate Highway I-70. The primary fiber optic telecommunication line was identified along the same northwest-southeast trend as the electric duct bank. Steam and water lines were indicated throughout the project area.

Geophysical surveys were performed to locate utilities at eleven locations previously staked by the project surveyor, Engineering Design Source, Inc. (EDSI). A total of 16 locations were originally identified, indicated as Potholes PH-1 through -16, however, Potholes PH-3, -4, -5, -8, and -14, were removed from the scope of services. The surveys were performed from January 13 through January 17, 2014 using a GSSI SIR 3000 ground penetrating radar unit with a 400 MHz antenna, Radiodetection RD-4000 meter, Pipehorn 800 Pipe and Cable locator, and EM31 frequency domain electromagnetic unit. Utilities were marked in the field using pin flags.

Vacuum excavations were performed at the eleven locations from January 13 through January 17, 2014. Observations made during excavation activities are summarized in Table 1. Field Reports are presented in Appendix A and photographs are presented in Appendix B. However, due to a camera malfunction the photograph of Pothole PH-13 was not saved and, therefore, not presented in the appendix.

The duct bank electric utility was located at a depth of approximately 71 inches within Pothole PH-16 and the telecommunications utility was identified at a depth of approximately 77 inches within Pothole PH-15. A steam line was traced and estimated to be approximately 16 feet

Size Type Material Northing Easting Elevation at

Ground Surface (ft-msl)

Depth to Top of Utility

Elevation at Top of Utility

(ft-msl)

Condition of Utility

PH-1 None Silty Clay 2" Water PVC 14037592.88 2443772.307 445.99 22" 444.16 Good PH-2 None Silty Clay 6" Water Cast Iron 14037836.81 2443860.8 446.91 57" 442.16 Good PH-3 Removed from scope PH-4 Removed from scope PH-5 Removed from scope

PH-6 None Silty Clay NA Steam NA 14038258.06 2444043.951 460.47 NA NA NA Not exposed at depth of 10 ft

RD4000 indicates approx depth of 16 ft PH-7 None Silty Clay 6" Water PVC 14038762.31 2444011.873 464.32 30" 461.82 Good PH-8 Removed from scope PH-9 None Silty Clay 10" Water Concrete Covered 14039805.26 2444241.421 467.66 62" 462.49 Good PH-10 None Silty Clay 10" Water Cast Iron 14039807.89 2444281.499 463.91 60" 458.91 Good PH-11 None Silty Clay 4" Water PVC 14039821.42 2444403.959 462.67 41" 459.25 Good PH-12 None Silty Clay 4" Water PVC 14039627.66 2444624.004 462.00 24" 460.00 Good PH-13 None Silty Clay 6" Water Cast Iron 14039427.18 2444838.354 466.35 41" 462.93 Good PH-14 Removed from scope PH-15 None Silty Clay 2-4" Telecommunication Metal Conduit 14038737.39 2444148.861 448.46 77" 442.04 Good PH-16 None Silty Clay 36" Electric Duct Bank 14038741.68 2444155.271 447.79 71" 441.87 Good

Test Hole

ST. LOUIS, MISSOURI

JEFFERSON NATIONAL EXPANSION MEMORIAL

TABLE 1

Utility Information

UTILITY LOCATING SERVICES

VACUUM EXCAVATION SUMMARY

Soil/Fill Material

Pavement Thickness/T ype Comments

APPENDIX A

FIELD REPORTS

APPENDIX B

EXCAVATION PHOTOGRAPHS

CAR 2015 - Jefferson National Expansion Memorial J017065.14 Utility Locating Services

Photograph 1 - PH-1: Top of sprinkler head. Line ends at sprinkler head.

Photograph 2 - PH-2: Tee in metal pipe. A joint is visible on the right side of the tee.

Photograph 3 - PH-6: View of hole with no utility exposed. Top of utility was not exposed, but estimated to be at a depth of approximately 16 feet.

Photograph 4 - PH-7: View of PVC water line.

Photograph 5 - PH-9: View of concrete covering pipe at turn in pipe.

Photograph 6 - PH-9: View of concrete covering pipe at turn in pipe.

Photograph 7 - PH-10: View of metal pipe under large rock or concrete.

Photograph 8 - PH-10: Close-up of metal pipe under large rock or concrete.

Photograph 9 - PH-11: View of PVC water line.

Photograph 10 - PH-12: View of PVC water line.

Photograph 11 - PH-15: View of top of metal conduit (AT&T).

Photograph 12 - PH-16: View of top of concrete duct bank (Ameren).

APPENDIX C

LIMITATIONS OF REPORT

UTILITY SURVEYING LIMITATIONS

1. This report was prepared for the exclusive use of the owner, architect, and engineer for evaluating the project as it relates to the technical aspects discussed herein. It can be made available to prospective contractors for information on factual data only and not as a warranty of subsurface conditions included in this report. Unless other contractual agreements were made, the services described in this report were carried out in accordance with the Terms for Geotechnology's Services that were attached to the proposal.

2. Geotechnology endeavored to perform the utility surveying in accordance with generally accepted practices of other consultants undertaking similar studies at the same time and in the same geographical area. The findings and conclusions stated herein must be considered not as scientific certainties, but rather as professional opinions concerning the significance of the limited data gathered during the course of the survey. No warranty, express or implied, is made.

3. The geophysical analyses and conclusions contained in this report are based on the site conditions, project layout, grid size, geophysical data, and interpretive procedures described herein and are for preliminary planning purposes only. Geotechnology can make no interpretation as to the presence of underground features at locations beyond the survey lines.

4. The possibility exits that abandoned, forgotten, non-tonable utilities or utilities without a tracer wire, utilities buried excessively deep beyond detection limits of standard geophysical survey methods, or undocumented utilities may be missed using standard utility surveying services. Geophysical exploration methods are non-intrusive, indirect, and potentially influenced by a variety of natural or man-made conditions. The potential for detecting the presence or absence of underground objects or voids is based on the quality of the recorded data as limited by site conditions, and on the interpretation of the data received;

hence, there will always be the potential of not observing a subsurface object or interpreting the presence of a subsurface object where one does not exist.