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Last Updated: Friday, February 3, 2012 11:30 AM

EXHIBIT 5.3 Extended Phase I Report Format and Content Guide

Exhibit 5.3 PDF version here

Extended Phase I Report Format

XPI Report Format
  • Title page
  • Summary of Findings (Abstract)
  • Table of Contents (optional)
  • Introduction
  • Site Context
  • Scope of Work
  • Study Results
  • Summary and Conclusions
  • References Cited
  • Maps
  • Other Figures
  • Tables
  • Site Record

The Extended Phase I (XPI) Report addresses the issue for which the work was undertaken, including the site limits to the project’s Area of Potential Effects (APE) and/or Area of Direct Impact (ADI), and the integrity of the deposit within the APE or ADI. Refer to Chapter 5, Section 5-5 for a complete discussion of XPI studies.

Title Page

  • In the title, identify the document as an XPI Report and cite the primary number and trinomial for the site.
  • Below the title, identify the highway project by name (e.g., "Proposed Truck Passing Lane") and reference the district, county, route, post miles, and expenditure authorization (e.g., "03‑SAC‑29, P.M. 28.7/31.5, K.P. 46.2/50.7, E.A. 03‑096110").
  • Provide the name, title, Professionally Qualified Staff (PQS) Level as described in Section 106 PA Attachment 1, and location of the report author(s). The senior author signs the title page of the final document.
  • Provide the name, title, and location of the District Environmental Branch Chief (EBC) for whom the report was prepared. The EBC approves the report by signing the title page in his/her signature block.
  • If a government permit for the excavation was issued, provide the name of permitting agency and the permit number.
  • Cite the USGS topographic quadrangle depicting the site area. Make sure to identify the topographic map by name, type (e.g., 7.5-minute), and date of latest revision.
  • List the primary number, trinomial, and any other permanent designations for the site.
  • Provide the date (month and year) of completion of the report at the bottom of the page.

Summary of Findings (Abstract)

Summarize the intent, methods, scope, and major findings of the study.

Table of Contents

List the major report sections, subheadings, appendices, tables, and figures, with page numbers.


Concisely describe or discuss:

  • Proposed highway project
  • Brief history of the project as it pertains to the site
  • Nature and purpose of the archaeological investigation
  • Dates of fieldwork
  • Names, titles, and qualifications of the personnel participating in the study
  • Any permits and permission obtained
  • Arrangements for curation of the collection
  • Disposition of any human bone, associated grave goods, or sacred objects
  • Scope and results of Native American consultation and monitoring (for prehistoric sites only)

Site Context

  • If the ASR for this project has positive findings, reference its background sections. Only newly relevant citations or changes in information previously provided should be discussed.
  • If background information has not been presented in a previous report, provide a brief summary and appropriate citations of relevant regional and local studies, following the content and format guidelines for background information contained in ASRs (see Exhibit 5.1).

Scope of Work

The scope of work discussion should:

  • Describe the study plan outlined in the proposal
  • Identify the methods used in fieldwork
  • Discuss methods used to define site limits or the deposit’s depth
  • State the number of person-hours expended
  • Describe measures taken to restore excavated areas to their previous appearance
  • Reference the study maps

Study Results

Describe and discuss the:

  • Extent of the site in terms of both horizontal boundaries and depth, as far as those are known
  • Excavated soil types and stratigraphy
  • Integrity of the cultural deposit, including discussions of any disrupting intrusions (e.g., roads, vandalism) that have changed the site’s condition or affected its integrity
  • Presence/absence of sub-surface features
  • Artifacts and ecofacts recovered, including total counts and/or weights and distributional data by test unit and by depth for each unit and data class
  • Temporal placement and functional interpretation of the site
  • (For historical archaeological site artifacts), description and enumeration by functional class and material type, including summaries of minimum numbers of items within individual features. In addition, the period of manufacture and use should be discussed, as well as any maker’s marks or other attributes contributing to the identification of temporal affiliation.

Summary and Conclusions

  • Summarize the results of the study in terms of the stated study goals.
  • Discuss the degree to which those goals were achieved, and any limiting factors.

References Cited

  • List all references cited.
  • Bibliographic format should follow the most recent style guide for American Antiquity.


All maps should display the district, county, route, post miles, and expenditure authorization. The Study Location Map and Study Site Map should have north arrows and graphic (analog) scales.

  • Study Vicinity Map: Depict the location of the study area on a county or District map.
  • Study Location Map: Depict the site location on a portion of the appropriate USGS topographic quadrangle. Make sure to identify the topographic map by name, type (e.g., 7.5-minute), and date of latest revision.
  • Study Site Map: This map should be scaled to show detail, at least 1”: 200'. An aerial photograph or engineering mapping may be used as a base map. Show the pertinent portion of the APE/ADI, right-of-way, site boundary, surface features, and locations of all study units (e.g., excavation units, surface scrapes, auger holes). Show topography and modern features, as appropriate.
  • Project Graphics: Include additional photographs, engineering cross sections, as-builts or other materials that illustrate project area conditions and the relationship of proposed project elements to the study finds.

Other Figures

There may be few figures in the report because, normally, little is found in XPI studies. Appropriate figures may include:

  • Sidewall profiles
  • Feature diagrams
  • Graphs and charts on recovered materials
  • Artifact illustrations
  • Photographs to illustrate testing work, features, and artifacts, as appropriate


Tables should be used to summarize the:

  • Types, sizes, and depths of excavation units
  • Distributions of artifacts, ecofacts, and features

Site Record

An updated site record should be appended, documenting the findings of the work.

Peer Review and Approval

Caltrans PQS certified at the Principal Investigator level must peer review the draft XPI Report following the guidelines in Exhibit 2.14: Guidelines for Peer Review of Cultural Resources Reports. Peer reviewers’ names should be kept on record and comments retained in the project files. Chapter 2 Section 2-5.5 and Exhibit 2.11 Table C contain additional guidance on peer reviews and reviews for approvals.

Only Caltrans PQS may review XPI Reports for approval, which the EBC approves. The Caltrans PQS or consultant who prepares the XPI Report signs, dates and includes his/her discipline, PQS level (as applicable) and District/Headquarters or affiliation. The Caltrans PQS at the Principal Investigator level reviewing the XPI Report for approval likewise signs, dates, and includes his/her PQS discipline, level and District. Finally, the EBC approves the XPI Report by signing and dating the document. See Chapter 5 Section 5-5.6 for more detailed information.