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November 21st, 2016 REPORT FOR SUBSURFACE UTILITY ENGINEERING Utility Designating and Locating Services SP6982-322 (Twin Ports Interchange) Submitted to: Minnesota Department of Transportation 1123 Mesaba Avenue Duluth, MN 55811 Submitted by: Utility Mapping Services, Inc. 3947 East Calvary Road Suite 206 Duluth, MN 55803 www.umsi.us 218.728.8087
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Page 1: REPORT FOR SUBSURFACE UTILITY ENGINEERING Utility … · 2018-02-13 · The following summarizes the results of subsurface utility engineering (SUE), utility designating and locating

November 21st, 2016

REPORT FOR SUBSURFACE UTILITY ENGINEERING Utility Designating and Locating Services

SP6982-322 (Twin Ports Interchange)

Submitted to:

Minnesota Department of Transportation 1123 Mesaba Avenue

Duluth, MN 55811

Submitted by:

Utility Mapping Services, Inc. 3947 East Calvary Road Suite 206

Duluth, MN 55803www.umsi.us 218.728.8087

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Table of Contents

Introduction .................................................................................................................................... 1 Data Limitations ............................................................................................................................. 1 Project Specific Scope of Work ..................................................................................................... 2 SUE Services Performed ............................................................................................................... 4

Phase I Utility Designating ......................................................................................................... 4 Utility Ownership ......................................................................................................................... 4 Supplemental Comments Regarding Existing Facilities ............................................................ 5 Utility Descriptions ...................................................................................................................... 5

Summary ................................................................................................................................. 5 Power and Street Lighting ....................................................................................................... 5 Natural Gas ............................................................................................................................. 5 Sanitary Sewer ........................................................................................................................ 5 Telecommunications ............................................................................................................... 5 Culinary Water ......................................................................................................................... 6 Storm Drains and Culverts ...................................................................................................... 6

Utility Discrepancies, Issues and Notes ........................................................................................ 6 Recommendations ......................................................................................................................... 7 State Law Caveat ........................................................................................................................... 8 Appendix A ..................................................................................................................................... 9

UTILITY DESIGNATNG AND LOCATING PROCESS .............................................................. 9 Phased Approach for Data Acquisition .................................................................................... 11

Data Acquisition Phase I Responsibilities ............................................................................ 11

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Introduction

The following summarizes the results of subsurface utility engineering (SUE), utility designating and locating services performed for design project: Twin Ports Interchange. This work was performed under a contract agreement between Utility Mapping Services, Inc. (UMS) and Minnesota Department of Transportation (MnDOT) (a.k.a. the “Client”). The purpose of this investigation was to interpret the presence of utilities within the specified project limits identified by the Client as described within this report. Professional judgment has been exercised to reasonably investigate, develop and present findings in a pragmatic manner for the ensuing project design and bid document preparation, while staying within the allotted budget. The users of this data are reminded that this information is for design purposes only, and not intended to be used in-lieu of the Gopher State One Call (Dial 811) utility locating process. The contractor is legally required to call Gopher State One Call two business days prior to construction. The data presented here are time sensitive and represent the results of the Phase I utility designating efforts at the time of the field investigation (August/September 2016). Specified project boundaries for the utility designating effort were identified in the original Detailed Work Plan dated August 5, 2016 with the area added on TH 53 from West First Street to Superior Street. Coverage of some facilities may extend outside these project limits as practical to capture surface features necessary to complete QL C alignments. The results of the subject utility designating investigation are presented in digital and hardcopy deliverables (see File Information section) including this report, a MicroStation utility reference file, and a hydraulic database report. To assure meaningful and proper usage, and to minimize risk of misinterpretation, this data must be kept, regarded, and interpreted in a collective, integral manner and in accordance and with understanding of CI/ASCE 38-02 standard guidelines.

This report documents the SUE field investigation and data interpretation. Particular attention has been given to special conditions including questionable interpretations, unusual installations or contradictory information obtained from record data and field findings. The information included herein enabled: 1) systematic determination of conflicts between existing utilities and proposed design and construction; and 2) proactive activities between the project development team and utility owners to value engineer resolutions. To best utilize the submitted utility investigation results, refer to Appendix A which provides an overview of the utility designating and locating investigation process.

Data Limitations UMS consistently performs professional utility designating services in accordance with CI/ASCE 38-02 guidelines and generally accepted engineering principles and practices at this time. However, a possibility exists that abandoned, forgotten, non-detectable, undocumented or newly installed utilities may not get mapped using standard records research and geophysical survey procedures. While the CI/ASCE 38-02 standard guidelines mitigate these issues, utilities possessing characteristics mentioned below can be missed while following standard utility designating and locating procedures:

1. Utilities lacking apparent available records and without apparent surface features. 2. Utilities with record information which is illegible, misleading, or incomplete.

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3. Utilities which are inaccurately reported or inaccurately represented by the utility owner as lying a significant distance from the true position.

4. Abandoned utilities without apparent surface features. 5. Utilities buried excessively deep, beyond detection limits of standard utility designating

equipment. 6. Non-conductive utilities buried in clay soil without apparent surface features. 7. Facilities installed subsequent to the utility designating field investigation effort.

A common problem occurs when the project involves facility owners and operators with insufficient records and non-conductive buried facilities, a situation often encountered with public works installations, infrastructure for oil and natural gas wells installed prior to 1960, and irrigation systems that have non-conductive water mains. Facilities mapped under these circumstances are often depicted as QL D during the utility designating (Phase I) field effort to keep operations and budgets at a practical level. As the design project progresses some depicted facilities may have to be upgraded to a higher quality level through more advanced geophysical prospecting and utility locating methods (Phase II) to properly identify and assess utility conflicts for design and construction. Designers, utility coordinators, and contractors must realize the CI/ASCE 38-02 utility mapping effort is an iterative acquisition and interpretation process; unless subsequent endeavors are made to upgrade designated quality levels, facilities depicted at lower quality levels, such as QL D, may be completely in error. In addition, depicted facilities and corresponding data are pertinent at the time in which field investigation operations are completed, and are subject to change. Final utility plans and data are for design purposes only, and reflect utility conditions at the time surveyed. Unless authorized to maintain and keep data sets current, UMS cannot be held responsible for changing utility scenarios after completion of field operations. Users of this data set must understand and adhere to the limitations associated with the designated quality levels assigned to the depicted facilities. QL C and QL D depictions are based on interpolations, extrapolations, and available record data; this data can be erroneous and should not be used alone for design development and bidding purposes. Additional utility designating and locating field efforts to upgrade data to QL B and A are strongly recommended for areas where accurate final design and construction planning and bidding is required. UMS strongly recommends users of this data, especially project engineers-of-record, become orientated with the CI/ASCE 38-02 standard guidelines and the corresponding data limitations inferred by the designated quality levels prior to employing the data set for design purposes. In addition, this report must always accompany the existing utility reference CADD file to ensure proper interpretation and usage of the data set. Any questions regarding this submittal should be directed to the SUE professional engineer-of-record.

Project Specific Scope of Work

The project specific scope of work included designating the utilities within specified project limits. However, coverage of some facilities may extend outside these limits as practical to capture surface features necessary to complete QL C alignments; additional utilities may exist outside these limits and are not depicted on the utility designating and locating data CADD reference file and map. The achieved quality levels for the Phase I utility designating effort are summarized in Table 1.

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The project scope included designating as practical to a target quality level B (QL B), or QL A if the facility was exposed and accessible, all identified underground utilities; however, to keep the investigation pragmatic, facilities that could not be detected using standard electromagnetic inductive tools were mapped to QL C and D during this Phase I utility field investigation effort. This iterative mapping procedure was used to allow the Owner the opportunity to evaluate the necessity to expend more resources during the Phase II effort to achieve a higher quality level designation on utilities in question. In some situations, QL objectives could not be met due to geophysical limitations such as excessive depth of facility, lack of tracer wire, non-conductive nature of pipe material, lack of surface features, lack of access, and/or insufficient records. Exceptions to Table 1 are noted on the MicroStation utility reference file and plan sheets.

Table 1. Utility Designating Results Utility Type (Buried)

Mains & Primary Laterals Mapped

Services and Secondary Laterals Mapped

Storm Drain N/A N/A

Sanitary Sewer QL A at manholes and inlets, QL B, C & QL D based on available records information & field observations

N/A

Culverts N/A N/A

Telecommunications / CATV QL A for surface features, QL B

QL B

Natural Gas and Propane QL B QL B

Traffic Signals QL A for surface features, QL B

QL B

ATMS N/A N/A

Lighting QL B N/A

Water Mains QL A for surface features, QL B, C and D

QL D as available on records

Power QL A for surface features, QL B

QL A for surface features, QL B

Irrigation N/A N/A

Petroleum N/A N/A

Military Communications N/A N/A

The project scope of work and work plans for utility designating included records research, field operations, data management, QA review and CADD development tasks, to produce deliverables outlined in the File Information section of this report.

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SUE Services Performed

Protocols as established by UMS, ASCE, and FHWA for SUE were followed for this project. Field operations proceeded on a segment-by-segment basis, and entailed reconnaissance, field designating, drainage work/manhole logging, and engineering survey campaigns.

Phase I Utility Designating A project kickoff meeting was held on September 13, 2016 with representatives from UMS, MnDOT, City of Duluth and the various utility owners. Utility designating work involved field meets and reconnaissance, collating information from records obtained from the utility owners, relating records with observable surface features, and geophysical surveys. The work performed was not 100% geophysical sweep of project area limits, but a retracing of distinct, known, detectable utility alignments within the project area to achieve Table 1 QL designating objectives wherever possible.

Utility Ownership

Table 3 specifies utility ownership and representative contact information for utilities identified within the subject utility designating investigation project limits. Information is current as of the date of submittal.

Table 3: Utility Ownership and Contacts

Utility Utility Type Contact Phone/Email

Western Lake Superior Sanitary District

Sanitary Sewer

Carrie Clement

218-722-3336 [email protected]

CenturyLink Telecommunications Michael Coughlin

218-723-4224 [email protected]

City of Duluth Water Sanitary Sewer/Gas

Tom Pfeffer 218-730-5104 [email protected]

Charter Telecommunications John Quade 218-529-8042 [email protected]

Consolidated Communications

Telecommunications Jeff Bright [email protected]

Northeast Service Corp.

Telecommunications Adam Lawery 218-748-7619 [email protected]

Minnesota Power Power Eric Clement 218-355-2831 [email protected]

Zayo Telecommunications Steve Senger 952-230-9660 [email protected]

MnDOT TMS Dave Mavec 218-725-2767 [email protected]

MnDOT Illumination and Traffic John Hoivik 218-725-2790 [email protected]

Wisconsin Central Limited/BNSF

R/R Roadmaster- Lakes Division

Charles VonRueden

715-394-1235 [email protected]

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Supplemental Comments Regarding Existing Facilities

Users of this information are reminded that mapping results presented and depicted with this submittal are representative as of completion of field investigation (August/September 2016) and are a pragmatic interpretation based on the systematic designating effort executed. Limitations may still exist as previously discussed in this report.

Utility Descriptions The following utility specific sections are general, non-inclusive overviews of utilities encountered within the project limits. Special mention is made to many, but not all, locations of potential utility conflicts. In all cases, please refer to the SUE MicroStation existing utility reference CADD file for utility details, location specific quality level attributes, and identified discrepancies. Utility designating investigations have produced considerable data and digital information which is presented via the CADD existing utility reference file. The objective is to depict and provide representative information for subsurface utilities present within the specified project limits. The following provides a descriptive summary of the depicted utilities, and discusses the quality level of that information. Summary For this investigation, QL A data is tied via an engineering survey to project survey control 3D coordinates; QL B data is tied to project horizontal coordinates, but elevations are at the ground surface. QL C alignments are straight lined between visible surface features, consequently they will not reflect ground surface undulations. QL D alignments are approximate only and will not reflect ground surface undulations. Explanation of areas where geophysical detection was poor or non-existent, degrading the quality of designation, will be provided in the following utility specific descriptions.

Power and Street Lighting Several overhead and buried power installations were mapped throughout the project corridor and are owned by Minnesota Power. The City of Duluth and MnDOT own the existing street lighting. The buried power installations were generally mapped QL B during this field investigation. The overhead alignments are based on surveyed pole and structure locations.

Natural Gas

The City of Duluth has a gas main running along Lower Michigan Street and crossings of I-35 near 26th Avenue, I-35 near Garfield Avenue, and TH 53 at Michigan Street. The gas facilities were generally mapped to QL B on the utility reference file.

Sanitary Sewer Western Lakes Sanitary Sewer District (WLSSD) owns and maintains gravity installations within the project corridor. They cross I-35 at 26th Avenue and also a nearby crossing of I-35 further north. The pipe sizes and material type were recorded at each location. The connections between each pipe end were designated QL C based on the apparent alignments observed at each pipe end or manhole. Telecommunications There are numerous fiber optic and telephone installations, both OH and UG, located throughout the project corridor. The utility owners include Charter, Centurylink, Zayo, Consolidated Communications,

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and Northeast Service Corporation. The buried facilities mapped during this field investigation were generally designated QL B on the utility reference CADD file.

Culinary Water

The City of Duluth water mains and services were designated throughout the project limits. Identified surface features (e.g., valves) were surveyed and logged. The water facilities mapped during this field investigation were generally designated QL B on the utility reference CADD file. Storm Drains and Culverts

Storm drains and culverts were not part of this effort.

Utility Discrepancies, Issues and Notes

The following summaries are provided to draw particular attention to special conditions such as discrepancies between utility records and field findings, unusual utilities, and utilities found to have incomplete or conflicting information. These issues may warrant further investigation. Natural Gas

The City of Duluth gas line crossing of I-35 near Garfield was unlocatable. No sizes were mentioned in the record information. The gas line in the alley south of First Street was unlocatable. There were tracer wire hookups but no reading was registered. The alignments shown have been drawn in QL D for the submittal and may require further investigation.

Sanitary Sewer

The City of Duluth has a force main under TH 53 on Michigan Street which was unlocatable. The alignments shown have been drawn in QL D for the submittal and may require further investigation. Some of the manholes were full of water which limited the field crew's ability to record pipe data such as size and material.

Structures 603, 623 and 624 are all a part of the sanitary sewer mainline. We were not able to open any of these structures. Pipe sizes, material are from record information provided.

WLSSD has a force main crossing I-35 near the pedestrian bridge that was unnlocatable. The alignments shown have been drawn in QL D for the submittal and may require further investigation.

WLSSD has a crossing of I-35 near 26th Avenue where no intermediate manhole, as shown on the record information, was found between the two manholes on either side of I-35. The alignments shown have been drawn in QL D for the submittal and may require further investigation.

WLSSD has a sanitary force main drawn between the manhole structure and the lift station in the interchange area below the Blatnik Bridge.

Several sewer manholes were either full of water or not accessible which lead to no indication of pipe material or size.

Water

City of Duluth waterline crosses I-35 at Garfield Avenue and was unlocatable due to no close above ground features to hook on It is drawn as QLD. No size was mentioned in the record information.

Deleted: .

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File Information Utility ownership, size and material (where available), designating quality level, and notes are included for each utility on the MicroStation existing utility reference file (SP6982_322ut.dgn). Digital photographs are also included with the submittal.

Table 4. Digital file submittals

File Name Description

SP6982_322ut.dgn Existing Utilities Reference File Utility ownership, specification, ASCE Quality Level, and notes are provided at each survey point along the utilities.

SP6982_322ut_SUE_Existing_Utility_Sheets.pdf SUE Notes Sheet Existing Utilities Plan Sheets

SP6982_SUE_Phase1_Report.pdf This document

SP6982-322_Hydraulic_Information.pdf Hydraulic Log Sheets (manholes, inlets, etc.)

The existing utility MicroStation reference file (SP6982_322ut.dgn) has data parsed within the appropriate levels based on the MnDOT design standards.

Recommendations UMS recommends vacuum excavations (test holes) or advanced geophysical methods be used to further investigate utilities identified to be in potential conflict with the proposed designs to better define positional and facility characteristics and explore conflict mitigation alternatives. Further exploration is also recommended on QL D and QL C depicted utilities where more accurate positioning is necessary to assess conflicts and also clarify or resolve discrepancies between field observations and record data. UMS should be kept advised throughout the design process to: 1) evaluate designer usage of the existing utility reference data from the utility designating and locating effort; and 2) provide recommendations for further utility investigations as deemed prudent based on previous UE investigation results. UMS recommends that MnDOT and the City of Duluth coordinate any utility permit requests within the project limits so as to keep this data current. QL A data should be requested of any utility work added within these project limits. UMS recommends a pre-bid job walk or a pre-bid meeting be held with MnDOT contractors or construction teams to allow UMS the opportunity to discuss results from this investigation and the usage and limitations of this data.

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State Law Caveat

A pragmatic effort has been made to systematically designate and depict buried utilities within the corridor to the extent practical for the authorized project budget. Final utility plans are for design purposes only and reflect subsurface utility conditions at the time surveyed. Existing utility locations depicted on the plans do not supersede Gopher State One Call demarcations of buried utilities, or relieve the contractor from the legal requirement to call One Call two working days prior to construction. UMS and the project design engineer should be notified of any discrepancies between the utility designating / locating survey and One Call markings, and the contractor shall use caution until discrepancies are resolved. Contractor shall call the utility notification service, Gopher State One Call, (800) 252-1166 or (651) 454-0002, before excavating as required by Law.

SEAL

I hereby certify that this engineering document was prepared by me or under my direct personal supervision and that I am a duly licensed Professional Engineer under the laws of the State of Minnesota.

Curt Fakler, P.E. Date 11/21/2016 License Number: 19410 My license renewal date is June 30, 2018

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Appendix A

UTILITY DESIGNATNG AND LOCATING PROCESS The project utility designating and locating investigation was performed in a systematic and practical manner, complying with policies promoted by the Federal Highway Administration (FHWA) and adhering to established standard guidelines published by the American Society of Civil Engineers (CI/ASCE 38-02) as described below.

ASCE Standard Guidelines for Utility Data Acquisition Data collection activities follow ASCE Standard Guidelines for the Collection and Depiction of Existing Subsurface Utility Data (Standard CI/ASCE 38-02, American Society of Civil Engineers, Reston, VA, 2002, 20 p). A significant contribution of the ASCE standard is development of a formalized procedure for qualifying and designating the general quality of the depicted individual facilities. Table 4 summarizes the four quality level (QL) definitions included in the ASCE standard. Included with the definitions are comments on the relative positional accuracy for the corresponding quality levels. Adherence to ASCE depiction standards along with the use of records research, geophysical methods, vacuum excavation, and engineering survey, and quality assurance measures, combined in a phased approach and guided by professional judgment, is often simply regarded as subsurface utility engineering or SUE. However, in proper context, SUE (now simply referred to as “Utility Engineering” or UE) is a rather complex and important series of engineering tasks and associated responsibilities; the utility mapping and designation of quality levels, in fact, provides the data set with which the UE process begins. In a broader sense, UE involves utilizing the qualified utility data sets to conduct the following engineering activities:

systematically identify, itemize, and define apparent conflicts between proposed designs and existing utilities;

optimize design development to curtail utility conflicts and risks;

identify and accommodate other infrastructure planned betterments and new installations;

conduct effective utility coordination in which resolutions to conflicts are derived that serve the best interests of the public and all stakeholders involved;

develop construction plans and bid documents that concisely identify and detail outstanding conflicts for construction planning, bidding, and execution; and

encourage value engineering and mitigation of cost implications to all infrastructure systems, which provide service to commerce, government, and the general public.

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Table 4. Quality level (QL) summary based on the ASCE Construction Institute Standard CI/ASCE 38-02

Quality Level (QL)

Description

Resulting Positional Accuracy and Data Completeness

D Information derived from existing records or oral recollections.

Data may be completely erroneous. Only the records indicate the utility is present. No direct field evidence is apparent.

C Information obtained by surveying and plotting visible above ground utility features and by using professional judgment in correlating information to available records and QL D information. QL C is usually used to map non-conductive pipes, deep utilities, or when electromagnetic (EM) signal interference and distortion is too significant.

Positional accuracy of surface features is typically to within 0.1 feet; however, alignments between surface features are often schematic only, providing general direction of alignment. Typically, according to FHWA studies, 15% to 30% of the utility data may be erroneous or missing.

B Information obtained through the application of appropriate surface geophysical methods to determine the existence and approximate horizontal position of subsurface utilities. QL B data should be reproducible at any point of their depiction using surface geophysical methods. This information is surveyed to applicable tolerances defined by the project and reduced onto plan documents. Standard geophysical methods map only the point of peak signal associated with a conductive utility. While a QL B point can be reproducible using geophysics, the signal can be distorted due to the superposition of EM fields from adjacent conductors and not lie horizontally above the target. Experienced SUE operators help identify and mitigate these issues. However, QL A data is recommended for design / construction work to be performed in the immediate proximity of QL B depicted utilities to provide definitive positional accuracy.

A positional accuracy statement with confidence level is not feasible unless electromagnetic fields are completely mapped and statistical analysis is used to derive alignments from the linear anomalies; in addition, sufficient ground truth sampling (e.g., test holes) is required. This level of geophysical survey and analysis effort required is often not practical or cost effective. In practice, experienced SUE designators can determine utility alignments reasonably well. Professional judgment is exercised to distinguish incidents of “bleed-over” and when apparent alignments don’t make sense. Available utility records are compared with field findings to confirm completeness of the QL B data. QL B rating, as a rule of thumb, is generally estimated to +/- 1 foot horizontally for utilities less than 5 feet deep. Horizontal accuracy degrades with depth. Utilities over 10 feet deep are very difficult to position horizontally using standard inductive equipment. Vertical location cannot be reliably derived using EM inductive methods as computed depths are often inconsistent and can be misleading unless ground truth (i.e. test holes) are available to confirm accuracy.

A Precise horizontal and vertical location of utilities obtained by the actual exposure (or verification of previously exposed and surveyed utilities) and subsequent measurement of subsurface utilities, usually at a specific point. Minimally intrusive excavation equipment is typically used to minimize the potential for utility damage. With QL A observations, relatively precise horizontal and vertical depictions, as well as other utility attribute data, are shown on plan documents. Accuracy is typically about 0.1 feet vertical, and to applicable horizontal survey and mapping accuracy as defined or expected by the project owner and as limited by the survey equipment and methodology used to perform the measurement.

This is the only QL to which a positional accuracy statement might be made. QL A is as accurate as the reference horizontal and vertical survey control will permit and the methodology used to make the measurement and derive the coordinates. Note that in some cases involving inverts, direct measurements may not be possible; consequently, QL A designation can only indicate that a relatively accurate position has been determined on the subject facility at that discrete location. In some cases an apparent minimum depth of clearance is provided. This is not QL A data as the utility has not been exposed. The utility apparently lies in line with the test hole, but is deeper than can be reached via vacuum excavation based on the detected geophysical signal. However, the minimum depth data is provided for informational purposes for planning consideration.

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Phased Approach for Data Acquisition An iterative two-phased approach for performing utility engineering data acquisition operations is typically incorporated for design efforts. The Phase I operation primarily involves utility designating and is generally to provide designers a comprehensive plan of existing utilities based on records research, field investigation, and geophysical survey methods, while utilizing professional judgment to keep the effort focused and at a pragmatic, cost effective level. The Phase I work includes efforts and processes to achieve the highest quality levels practical without vacuum excavation methods, and typically results in a mixture of QL D, C, and B data; some QL A data will also be provided as available through manholes, vaults, or where facilities daylight. The Phase I designated utility data is provided to the client for review and evaluation, and used to identify locations where more detailed data is required. For the purposes of this work, “designate” means to establish by engineering and drafting practices the presence and horizontal location of subsurface utilities using, to the fullest extent practical, available records and geophysical detection methods, including, without limitation, magnetic, electromagnetic (EM), and, if authorized, ground penetrating radar (GPR) techniques. Utilities detected and mapped using geophysical methods are generally designated as QL B. Non-conductive piping that does not have a tracer wire is generally mapped to QL C during Phase I, unless GPR or electromagnetic sonde methods are authorized and practical for designating purposes. Typically it is more efficient to map non-conductive utilities to QL C during the Phase I, with a subsequent Phase II effort to obtain QL A data as necessary to complete the design with a reasonable degree of confidence. Telecommunication, electrical, metal pipe, and facilities with tracer wire are typically mapped to QL B during the Phase I effort. Non-conductive water mains, sanitary sewer and storm drains are usually mapped to QL C during the Phase I, with pipe inverts at manhole locations mapped to QL A. The Phase II field investigation primarily encompasses utility locating, which involves vacuum excavations performed at discrete test hole locations where utility conflicts are a concern, and more detailed QL A data, including precise three-dimensional coordinates, may be required to complete designs and mitigate/accommodate conflicts. For the purposes of this work, “locate” means to establish by engineering, surveying, drafting, and vacuum excavation practices the accurate horizontal and vertical position of subsurface utilities with vertical tolerances of 0.1 feet based on referenced benchmarks. A written log of each test hole is prepared, derived elevations are transcribed onto CADD reference files, and “locate” points are mapped to QL A on the plans. Test hole locations are identified with the client/designer prior to conducting field operations. Phase II operations can also include more advanced and involved geophysical methods to upgrade QL D and C data to QL B as feasible and desired. UMS implements this phased investigation process by performing the following series of tasks and associated responsibilities. Data Acquisition Phase I Responsibilities

The following checklist describes a typical Phase I project: Discuss with the client project management the specific scope of work for Phase I operations. Provide appropriate equipment, personnel, traffic control and supplies. Conduct utility records research, investigate site conditions, and identify applicable project

limits. Designate the existing underground utilities using geophysical instruments and based upon

existing records and observable surface features. This is not a 100% sweep of the project area limits, but retracing distinct, known, detectable utility alignments within the project area to obtain QL B data wherever possible, collating information from records obtained from the utility

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owners, and relating records with observable surface features. Much effort is spent determining and evaluating discrepancies between existing records and field findings.

Conduct engineering survey of designated utilities to establish horizontal coordinates for mapping.

Prepare CADD drawings depicting all collected information on MicroStation reference files. Review and correct plan sheets against utility records, field sketches, and field notes. Prepare report summarizing field findings and identifying discrepancies between utility records

and field findings (this report). Conduct QA/QC reviews. Professional Engineer overseeing all investigation efforts, and report and plan preparations seals

work product.

Data Acquisition Phase II Responsibilities

The following checklist describes a typical Phase II project: Discuss with the client project management the specific scope of work for Phase II operations. Provide standard equipment, personnel, traffic control, and supplies. Obtain necessary work and access permits. Coordinate with property owners, utility representatives, and one-call services. Perform advanced or additional geophysical detection to upgrade QL D and C data to QL B as

feasible and desired. Perform geophysical sweep for the targeted underground utility. Excavate test holes to safely expose the utility, preserving integrity of hole and area. Conduct engineering survey and record exposed utility. Provide permanent restoration of the pavement and location. Evaluate and compare test hole information with utility records and identify conflicts. Prepare CADD drawings showing all information collected in a plan format. Conduct QA/QC reviews Professional Engineer overseeing all investigation efforts and submittals seals work product.