Utility Mapping Services Inc.

INTRODUCTION

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PROJECT APPROACH

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UMS General SUE Approach for Designating/Locating

ASCE Standards for SUE

Data collection activities will follow the recently enacted 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). Perhaps the most significant contribution of the ASCE standard is the development of a formalized procedure for identifying the quality associated with the survey of individual facilities. Table 5 summarizes the four quality level (QL) definitions included in the ASCE standard along with 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 land survey combined in a phased approach and guided by professional judgment, is generally referred to as Subsurface Utility Engineering or SUE. Protocols for SUE, as established by ASCE and the Federal Highway Administration (FHWA) will be followed for each project. The SUE method provides a framework to obtain and represent the requested utility information in an efficient, systematic manner.

Two-Phased Project Approach for Designating and Locating

The intent of the SUE Phase I operation, also referred to as utility designating, 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 (QL) practical without vacuum excavation methods and can result in a mixture of QL D, C, B, and A data. The Phase I designated utility data is provided to the project design team for review and evaluation, and to identify locations where more detailed data is required.

For this process, “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 and ground penetrating radar (GPR) techniques. Utilities designated using geophysical methods are generally mapped to QL B. Non-conductive piping that does not have a trace wire are generally mapped during Phase I using the QL C (as described below), 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 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 SUE Phase II investigation primarily involves utility locating utilizing vacuum excavation 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 this process, “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 0.05 feet based on referenced benchmarks. A written log of each test hole is prepared, derived elevations are transcribed onto CAD reference files, and “locate” points are mapped to Quality Level A on the plans. Test-hole locations are identified with the designer prior to conducting field operations.

UMS Utility Designating (SUE Phase I) Responsibilities

The following checklist describes a typical Phase I project:

• Meet with client project management to develop project specific scope of work, cost estimate, and work schedule for Phase I SUE operations.

• Provide appropriate designating equipment, personnel, traffic control and supplies for conducting SUE field operations.

• Conduct utility records research, investigate site conditions, identify applicable project limits.

• Obtain necessary permits and rights of entry from the State, local jurisdictions, and/or private landowners.

• Designate the existing underground utilities using geophysical instruments and based upon existing records and observable surface features. This is a retracing of distinct, known, detectable utility alignments within the project area to obtain QL B data wherever possible, collating information from records obtained from the utility owners and relating records with observable surface features.

• Conduct land survey of designated utilities to establish horizontal coordinates for mapping. Survey of utility features and detected utilities will be tied to the existing project control network using global positioning system (GPS) real-time kinematic (RTK) and/or conventional land survey methods.

• Prepare CAD drawings depicting all collected information on MicroStation reference files.

• Review plans against utility records, field sketches, and field notes. Prepare report summarizing field findings and identifying discrepancies between utility records and field findings.

• Conduct QA/QC reviews

• Professional Engineer overseeing all investigation efforts and report and plan preparations will seal work product.

UMS Utility Designating (Phase I) Deliverables

Phase I deliverables will include digital and hardcopy issues of the following:

• Existing utility MicroStation reference files compliant with the client's CADD standards.

• Georeferenced utility attribute data including utility ownership, utility specifications, ASCE quality level designation, and discrepancies (within the MicroStation utility reference file).

• A submittal report summarizing the investigation effort, findings, discrepancies encountered, outstanding issues and recommendations for further investigation. (Adobe PDF format)

• Georeferenced digital photographs of utility features (Adobe PDF format) with photo identification vectors showing photograph location orientation included on the MicroStation reference file.

• Completed UMS manhole log sheets with flow direction, pipe specifications, and invert depth and elevation data (Adobe PDF format).

• Completed UMS utility feature log sheets documenting work-related communications between UMS, utility owners, outside agencies, and/or private landowners (Adobe PDF format).

Electronic data can be submitted by uploading files to a designated FTP site, or by courier and CD-ROM.

UMS Utility Locating (SUE Phase II) Responsibilities

The following checklist describes a typical SUE Phase II project:

• Meet with client to develop a project specific scope of work, cost estimate, and project schedule for SUE Phase II operations.

• Provide standard designating and locating equipment, personnel, traffic control, and supplies.

• Obtain necessary permits and rights of entry from the State, local jurisdictions, and/or private landowners.

• Adhere to OSHA health and safety practices.

• Coordinate with property owners, utility representatives, and one-call services.

• Perform geophysical sweep for the targeted underground utility.

• Neatly cut and remove the existing pavement or surface, with a maximum cut area of 225 square inches unless unusual circumstances exist. Vertical and horizontal exploration will be performed through this cut.

• Excavate test holes to safely expose the utility, preserving integrity of hole and area. Appropriate safety measures will be incorporated to ensure safety of locating operators and the public. UMS will comply with applicable utility damage prevention laws and coordinate with utility inspectors as required.

• Investigate, evaluate, measure and record all utility data ascertainable from each test hole site.

• Be responsible for damage to the utility directly caused by the excavation work. In the event of utility damage, UMS will stop work and notify appropriate agencies, including the utility owner. Work will not resume until the owner has determined what action to take. UMS will be liable for costs associated with the repair or replacement of the facility for the damages inflicted by UMS. UMS will not be responsible for effects resulting from exposing facilities that: 1) are previously damaged; 2) were installed using faulty construction methods; 3) were not installed to the legal requirements established by applicable state statutes, the United Builders Code and APWA; and 4) have degraded over time through corrosion or strained due to settlement, resulting in compromised integrity. UMS will contact the appropriate environmental coordinator immediately if hazardous materials are encountered and recognized.

• Tie all vertical elevations to a minimum of two checked benchmarks. The accuracy of these turns will be in accordance with established surveying practices.

• Provide permanent restoration of the pavement and location. UMS will be responsible for the backfill and surface restoration, and return if necessary if restoration measures were insufficient to correct the situation at no extra cost.

• Backfill the excavation with approved material around the utility structure and compact, in lifts, with appropriate devices.

• Furnish, install, and color code a permanent above the ground marker (e.g., PK nail, peg, steel pin, or hub) directly above the centerline of the structure and record the elevation of the marker.

• Provide complete cleanup of the work site to equal or better condition than existing prior to excavation.

• Evaluate and compare test-hole information with utility records and identify conflicts.

• Prepare CAD drawings showing all information collected in a plan format.

• Conduct QA/QC reviews

• A registered professional engineer overseeing investigation efforts and report and plan preparations will seal work product, certifying the accuracy of the submittals and establishing corresponding responsibility for professional errors and omissions.

SUE Phase II deliverables will include digital and hardcopy issues of the following:

UMS Utility Locating (SUE Phase II) Deliverables

• Existing utility MicroStation reference files compliant with the client's standards updated to include test hole obtained depth and elevation data.

• Georeferenced utility test hole data including utility ownership, utility specifications, ASCE quality level designation, depth and elevation data, and discrepancies (MicroSoft Excel format and within the MicroStation utility reference file).

• A submittal report summarizing the investigation effort, findings, discrepancies encountered, outstanding issues and recommendations for further investigation. (Adobe PDF format)

• Georeferenced digital photographs of utility features exposed through test hole operations (Adobe PDF format) with photo identification of the corresponding test hole number.

• Completed UMS test hole log sheets with apparent conduit dimensions, color, construction, depth, and elevation data, including observed pavement thickness and soil conditions. (Adobe PDF format).

The following test hole information will be recorded:

• Elevation of the top and/or bottom of the utility, tied to datum of the furnished plan

• Elevation of the existing grade over the utility at the test hole

• Horizontal location referenced to the project coordinate datum after performing all required survey work

• Outside diameter of the pipe or width of the duct banks and configuration on the non-encased multiconduit systems

• Utility structure material compositions

• Pavement thickness and type, where applicable

• Identification of benchmarks used to determine elevations

• Elevation tied to existing vertical control to within a statistically derived tolerance of +/- 0.05ft

• Updates to the UMS utility feature log sheets documenting work-related communications between UMS, utility owners, outside agencies, and/or private landowners (Adobe PDF format).

In addition, UMS will process data using a software package that permits elevations to be assigned to the utilities and will place corresponding cells for the utilities within the cross sections to aid the engineer during earthwork and 3D design efforts.