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

EXHIBIT 5.2 Extended Phase I Proposal Format and Content Guide

Exhibit 5.2 PDF version here.

Extended Phase I Proposal Format

XPI Proposal Format
  • Title page
  • Table of Contents (optional)
  • Introduction
  • Site Context
  • Scope of Work
  • Decision Thresholds
  • Timetable
  • Native American Coordination (Prehistoric sites)
  • Curation
  • Archaeological Permits
  • References Cited
  • Maps
  • Other Figures
  • Site Record Forms

An Extended Phase I (XPI) study is an extension of the identification phase for archaeological resources, meeting the requirements of 36 CFR 800.4(b), “to identify historic properties within the area of potential effects,” and similar requirements under CEQA. The XPI Proposal is used to explain the reasons for the XPI study, to describe the proposed field methods, and will be used as the basis for determining when the study goals have been met and fieldwork can cease. Refer to Chapter 5, Section 5-5 for a complete discussion of Extended Phase I studies.

Title Page

  • In the title, identify the document as a proposal for an XPI excavation and cite the primary number and trinomial for the site.
  • Below the title identify the proposed highway project by name (e.g. "Proposed Truck Passing Lane") and identify 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 proposal 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 proposal by signing the title page in his/her signature block.
  • Provide the date (month and year) of completion of the proposal at the bottom of the page.

Table of Contents

A table of contents is usually not necessary for the XPI proposal, since it is limited to a few pages. If the report is large enough to make a table helpful, list the major report sections subheadings, appendices, tables, and figures, with page numbers.


  • Briefly describe the site.
  • Explain why an XPI study is needed (see relevant discussions in Chapter 5 and Chapter 6), referencing the National Historic Preservation Act (NHPA), 36 CFR §800, and/or CEQA, as appropriate.
  • If the XPI is to verify a lack of subsurface deposit, briefly explain the argument for this supposition.
  • Summarize the goals of the study.

Site Context

  • If a positive ASR has been prepared for this project, reference its background sections.
  • If background information has not been presented in a previous report, provide a limited background and appropriate citations of relevant regional and local studies.
  • Provide information relevant to understanding the site and expected archaeological deposits, and briefly discuss the types of research issues sites of this nature might be able to address.

Scope of Work

  • Briefly describe the proposed field methods, including the types, numbers, and placement of units, and the screen size(s) proposed.
  • Discuss any problems or special conditions that might require modification of the proposed work program.
  • Discuss the key personnel and number of crewmembers, their qualifications and estimated duration of their participation.

Decision Thresholds

This section defines specific thresholds for assessing when the goals of the study have been met.

  • Discuss the potential findings that would justify a conclusion that a substantial subsurface deposit is not present in the areas being tested, or that the deposit is so disturbed that it would no longer have the potential to contribute to eligibility for the site as a whole.
  • Discuss the potential findings that would justify a conclusion that an intact deposit is present, and that further evaluation of the site may be required.
  • Discuss circumstances under which additional XPI effort might be needed to achieve the study goals.


  • Provide a schedule for completion of the proposed work. This timetable may be presented in text or graphic form (e.g., as a timeline).
  • Include the start date and the duration of fieldwork, laboratory processing, and report preparation.
  • Include any arrangements for gaining permission to conduct the study, including any necessary permits.

Native American Coordination (for Prehistoric Archaeological Sites)

  • Describe the previous and anticipated future involvement of Native Americans through consultation and monitoring.
  • Explicitly identify action to be taken if human bone, associated grave goods, or sacred objects are found.


  • Indicate the facility that will curate the cultural materials recovered and the accession number, if known. If arrangements with a facility cannot be completed prior to work, identify how and where materials will be maintained until an agreement is reached
  • If recovered materials will not be curated, provide details of any discard policy that will be used.

Archaeological Permits

  • Discuss any permits that may be needed to conduct the work.
  • Include permit acquisition in the timetable discussed above in the Timetable.

References Cited

  • A bibliography is usually not necessary, but any references in the text should be listed.
  • Citations may follow the most recent style guide for American Antiquity.


All maps should display the district, county, route, postmiles, and expenditure authorization, and should have north arrows and scales.

  • Project Vicinity Map: Indicate the site location on a county or district map.
  • Project Location Map: Indicate 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.
  • Site Map: This map should be scaled to show detail at 1”: 200’ or better and can be based on an aerial photograph or engineering map. Show the known site boundaries in relation to the APE/ADI, as well as the portion of the site to undergo XPI excavation. If possible, depict proposed excavation locations.
  • Other Graphics: It may be useful to include additional photographs, engineering cross sections, as-builts or other materials to illustrate project area conditions and support the proposal.

Site Record Forms

Attach all primary and site record forms available for the site, including initial and updated forms.

Peer Review and Approval

Caltrans PQS certified at the Principal Investigator level must peer review the draft XPI Proposal 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 Proposals for approval, which the EBC approves. The Caltrans PQS or consultant who prepares the XPI Proposal 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 Proposal for approval likewise signs, dates, and includes his/her PQS discipline, level and District. Finally, the EBC approves the XPI Proposal by signing and dating the document. See Chapter 5 Section 5-5.2 for more detailed information.