Short answer: Most firms publish a 2-4 week standard for a Phase I Environmental Site Assessment (ESA), which is 10-20 business days, and LightBox EDR’s May 2023 benchmark survey put the average at 16 business days. Several firms now publish 5-10 day standards. Compyle Environmental delivers in 5 business days from authorization and confirmed site access, or 3 business days with a $400 rush.
On a specific property, how long a Phase 1 environmental assessment takes depends less on a consultant’s headline number than on three things no consultant fully controls: when someone can let the assessor in, how quickly the buyer’s own information arrives, and whether a government agency has to pull a file. Figures for named firms below are as listed on their websites on October 19 or 20, 2026.
How long does a Phase 1 environmental take? Published turnaround times
The only industry-wide survey data we found come from LightBox EDR, which surveys environmental professionals every 5 years. Its 2023 Benchmark Survey, answered by more than 300 environmental professionals, found an average of 16 business days for a Phase I that meets the All Appropriate Inquiries (AAI) rule on a conventional property with no non-scope issues. (ASTM treats matters such as asbestos and radon as outside the scope of a standard Phase I.)
The 2018 edition found most firms reporting 2 or 3 business weeks. Firm websites in October 2026 show the same range, and several firms now publish standards of 5-10 days. Firms that say when their clock starts use different starting points, which matters as much as the number:
| Source | Published standard | When the clock starts |
|---|---|---|
| LightBox EDR 2023 survey | 16 business days (average) | Not defined (survey) |
| Geotill | 2-3 weeks | Order date |
| A3 Environmental | 3 weeks, about 12-16 business days | Project authorization |
| AEI Consultants | 2-4 weeks (described as typical) | Not stated |
| Aegis Environmental | 2-4 weeks (described as typical) | Not stated |
| iSi Environmental | 10-14 business days | Not stated |
| FastPhase1 | 10 days | After the site visit |
| Kross Inspectors | 5 business days typical on its Phase I page; 5-7 business days on its services and quote pages | Not stated |
| Compyle Environmental | 5 business days | Authorization and confirmed site access |
A week is 5 business days, so 2-4 weeks is 10-20 business days, and each federal holiday in the period adds a day. A clock that starts after the site visit can run well past its headline number. Ask any firm, including us, when its clock starts and what pauses it.
The Phase I timeline, step by step
A Phase I is a set of parallel tasks, not one sequence. The Environmental Professional (EP), the person who meets the license, education and experience requirements in 40 CFR 312.10 and signs the report, can finish only when the slowest input has arrived or has been recorded as a data gap.
| Step | What happens | Typical time | Who sets the pace |
|---|---|---|---|
| 1. Authorization | You sign the engagement, name the user and relying parties, and agree on any extra scope, such as asbestos or radon. | As soon as the signed agreement is back | You and the firm |
| 2. Records and data package | Government database report plus historical aerials, fire insurance maps, city directories and topographic maps (40 CFR 312.24 and 312.26). | 1-3 days for LightBox’s Premium package, lien and AUL search excluded; 3-5 business days for an ERIS city directory | Data vendor |
| 3. Historical research | Uses traced to the first developed use or 1940, whichever is earlier, with more sources when “retail” could hide a dry cleaner. | Depends on the history | EP |
| 4. Regulatory database review | Listings reviewed at the AAI search distances, such as 1 mile for National Priorities List sites and half a mile for leaking tanks. | Part of the desk review | EP |
| 5. Agency file requests | Agency files reviewed when the property or an adjoining property is listed, or the report explains why not. | First response due in 5-20 days under every law below except Florida’s, which sets no number; the files can take longer | The agency |
| 6. Site visit | On-site inspection and a view of adjoining properties (40 CFR 312.27). | Set by when access is available | You, the owner, tenants |
| 7. Interviews and user information | Owner, site manager and occupants interviewed (312.23), plus state or local government officials (E1527-21, section 11); your own inquiries, including the lien search (312.22). | Depends on responses; 3 business days or less for AFX Research’s standard lien and AUL report | You, the owner, tenants |
| 8. EP review and report | Findings, opinions, conclusions, data gaps and the EP’s two declarations, in a signed report (312.21). | Report writing averaged 6.8 hours (LightBox 2023) | EP |
The professional work is measured in hours. LightBox found report writing was the most time-consuming single task, and EDR’s 2018 survey found more hours went to writing than to the site visit and quality review combined. Most of the elapsed time is waiting for a data package, an access window, an agency or the buyer’s information, and much of that waiting can be cut on day one.
What slows a Phase I down, and what you can do about each
Site access
The site visit is required, and under 40 CFR 312.27(c) a seller’s refusal of access does not excuse it. If a building cannot be entered and its use often leads to contamination, ASTM’s own example treats that as a significant data gap (E1527-21, section 12.5.1).
What to do: name one contact with keys to every area, tell tenants a visit is coming, and make sure the purchase agreement gives you and your consultant access.
Your own inquiries and the user questionnaire
The AAI rule gives the buyer (ASTM calls it the user) its own tasks: the environmental lien search, any specialized knowledge, whether the price reflects fair market value, and commonly known information (40 CFR 312.22). ASTM E1527-21, the commercial Phase I standard EPA recognizes in 40 CFR 312.11, asks for specialized knowledge before the site visit (section 6.3). Its User Questionnaire (Appendix X3) is optional but is the usual way that information arrives.
What to do: return the questionnaire with the order. You need not disclose the price, but tell the EP if you believe it is below market because of contamination (section 6.5).
Prior reports
Before the site visit, the EP asks the owner, site manager and user for helpful documents: earlier assessments and investigations, permits, tank registrations, agency notices and recorded use restrictions (section 10.8). Records you provide can also stand in for an agency file review when the EP finds them sufficient (section 8.2.3.2).
What to do: send every prior Phase I and Phase II, tank closure letter and no further action letter you or the seller have, even old ones.
Title and lien information
The AAI rule requires a search for recorded environmental cleanup liens (40 CFR 312.25). ASTM pairs it with a search of title and judicial records for activity and use limitations (AULs), such as a recorded restriction that limits how a cleaned-up property may be used, and makes both the user’s job unless the EP is hired for them (section 6.2). The title commitment or preliminary title report for the deal can satisfy the search, as can a separate lien and AUL report covering 1980 to the present. LightBox excludes the lien and AUL search from its 1-3 day package turnaround.
What to do: forward the title commitment when the title company issues it, or order a lien and AUL report from a title company or search vendor on day one.
Multiple parcels and long histories
Each parcel can carry its own addresses, records and title. ASTM expects the EP to account for parcels and addresses that changed over time (section 8.3.2) and, on retail, industrial or manufacturing properties, to keep looking when more sources could identify a specific past use (EPA’s comparison of the AAI rule and E1527-21).
What to do: list every parcel number and former address you know of. We require a scope review and a fixed quote before authorization for multiple parcels, including contiguous parcels under one owner.
Interviews that go unanswered
Under E1527-21, an interview section is not incomplete just because someone other than the user does not answer, as long as the EP records the questions asked and makes at least one reasonable follow-up (section 10.7.2).
What to do: give the firm direct phone numbers and email addresses for the owner, site manager and tenants.
Agency file requests: the step a rush cannot buy
When the property or an adjoining property appears on a listed government database, E1527-21 expects the EP to review the pertinent agency files or explain in the report why not (section 8.2.3.1). Alternatives include records kept on site, records you provide, local agency records and interviews with regulators, and the EP must say whether they were sufficient (section 8.2.3.2).
ASTM also caps how long the standard expects anyone to wait: information counts as obtainable within reasonable time and cost only if the source provides it within 20 calendar days of a request at a nominal cost, or allows an in-person review within 20 calendar days (section 8.1.5, the same rule McGuireWoods quoted for E1527-13). Public-records laws set the agency’s side:
| Agency | What the law requires | Rule |
|---|---|---|
| Federal, including EPA regional offices | A determination within 20 working days; up to 10 more in unusual circumstances | 5 U.S.C. 552(a)(6) |
| California | A determination within 10 days, with an estimated date for the records; up to 14 more days in unusual circumstances | Cal. Gov. Code 7922.535 |
| Florida | Prompt acknowledgment and a good-faith response; no fixed number of days | Fla. Stat. 119.07(1)(c) |
| New Jersey | Grant or deny within 7 business days, or 14 for a commercial-purpose request; archived records up to 21 more business days | N.J.S.A. 47:1A-5(i) |
| New York | Within 5 business days, produce, deny or acknowledge with an approximate date; a reason and a date certain if granting will take more than 20 business days from the acknowledgment | N.Y. Public Officers Law 89(3)(a) |
| Texas | Produce promptly; if not possible within 10 business days, certify that in writing and set a date | Tex. Gov’t Code 552.221 |
These are response deadlines, not delivery promises, and most allow extensions. iSi Environmental names state file-review backlogs, at 5 days to 8 weeks depending on the agency, as the most common reason Phase Is miss closing dates. Curren Environmental tells buyers to budget 4-6 weeks for a Phase I when older state agency reports have to be pulled from archives, against about 3 weeks for a simple site.
When a file has not arrived, the data gap rules apply. A data gap is required information that could not be obtained despite good-faith efforts (40 CFR 312.10), and the report must identify the data gaps that affect the EP’s ability to identify conditions indicative of releases and comment on their significance (40 CFR 312.21(c)(2)). Under E1527-21, a gap is significant only if it affects the EP’s ability to identify a recognized environmental condition (REC), the standard’s term for a release-related finding. Significant gaps go in the findings and conclusions, with the EP’s view of how they affect the opinion (sections 12.5.1, 12.6.2 and 12.7).
Not every firm waits for the files. Curren Environmental, a New Jersey consultant that reviews Phase I reports for financial clients, wrote in May 2024 that a common thread in those reports is that they were issued before public-records requests and file reviews were finished, with an addendum promised if files turn up. Ask whether any agency request is still open at delivery and how the report treats it. Our engagement terms say agency response times beyond our control extend the delivery date day for day.
How to plan a Phase I around your closing date
The hard stop is the day you take title. The landowner defenses in CERCLA, the federal Superfund law, require all appropriate inquiries to be done on or before acquisition (42 U.S.C. 9601(35)(B)), and EPA’s enforcement guidance says purchasers cannot perform them afterward (page 5). The Phase I meets one requirement of the bona fide prospective purchaser defense most buyers rely on. The defense also requires your own inquiries, continuing obligations after closing and the other conditions in 42 U.S.C. 9601(40), such as having no affiliation with a party liable for the contamination.
Within that limit, work back from the earlier of your due diligence deadline and your lender’s deadline, counting business days. Take a purchase agreement signed Monday, November 2, 2026 with a 30-day due diligence period ending Wednesday, December 2. With Veterans Day and Thanksgiving, that leaves 20 business days after signing. If the Phase I is authorized and access confirmed on November 2:
| Turnaround | Report delivered | Business days left in due diligence |
|---|---|---|
| 5 business days | Monday, November 9 | 15 |
| 16 business days (LightBox 2023 average) | Wednesday, November 25 | 4 |
| 20 business days (top of a 2-4 week quote) | Wednesday, December 2 | 0 |
The days left are your room to act on a finding. In EDR’s 2018 survey, environmental professionals said close to a quarter of their Phase Is lead to a Phase II. Published Phase II timelines run from 2-4 weeks (iSi Environmental, depending on the laboratory queue and the site) to a typical 4-8 weeks (AEI Consultants, which says complex sites can take several months). A report that lands on the last day leaves no time to decide on a Phase II, a price change or an extension.
The opposite mistake is ordering too early. The interviews, lien search, government records review, site visit and EP declaration must be conducted or updated within 180 days before you take title (40 CFR 312.20(b)), and the rest of the inquiry within one year (312.20(a)). Under E1527-21 the report date is not the test; the component dates are, and the report must list the key dates (sections 4.6.1 and 4.6.3). For a lease or refinance, the clock runs to that transaction’s date.
The same January 15, 2027 closing with two order dates:
| Date or status | Ordered at the letter of intent | Ordered when the contract is signed |
|---|---|---|
| Oldest work in the report (records search) | Monday, June 15, 2026 | Monday, November 2, 2026 |
| Last closing date without an update (180 days) | Saturday, December 12, 2026 | Saturday, May 1, 2027 |
| Last closing date with an update of the five components (one year) | Tuesday, June 15, 2027 | Tuesday, November 2, 2027 |
| Status at a Friday, January 15, 2027 closing | Update of the five components required (the rest is still within one year) | Within 180 days, with 106 days of room |
Our Phase I validity calculator runs these dates for your report, and the Phase I ESA 180-day rule guide explains updates and lender clocks. If a closing slips past 180 days, an update brings the five components current, with the lien search still your task unless you hire the EP for it. Ours costs $595 for a report we wrote and takes 4 business days. For another firm’s report, we confirm scope and price within 1 business hour of seeing it.
Three more points to plan around:
- SBA loans. Under SOP 50 10 8.1, environmental reports must be dated within one year of the date the SBA loan number is issued (Section A, Chapter 5, Paragraph E.3), and SBA will accept for review an otherwise AAI-compliant Phase I dated within that year, notwithstanding EPA’s 180-day update rule (Appendix 4, definition of Phase I Environmental Site Assessment). The same definition says parties “may still wish to strictly comply with EPA’s regulatory timeframes to avoid jeopardizing legal and regulatory protections.” Plan to whichever clock ends first.
- SBA loans that may not need a Phase I. Where no current or known prior use of the property matches an environmentally sensitive NAICS code in Appendix 6, the SOP’s minimum for a loan over $250,000 is an Environmental Questionnaire plus a Records Search with Risk Assessment (RSRA), a records review with no site visit. A Phase I follows if the RSRA finds anything other than low risk (Paragraph E.4), and lenders can require more (Paragraph E.2).
- Ordering before you sign. Some buyers want the report before they commit. Check that a realistic closing date, not the contract date, falls within 180 days of the oldest of the five time-sensitive components.
Can a rush shorten a Phase I? Published rush terms
Few firms publish rush prices, and in LightBox’s 2023 survey 25% of responding consultants said they charge a premium for faster delivery. Rush terms published by the firms above, October 2026 (Aegis describes typical market terms rather than its own):
| Firm | Standard turnaround | Rush turnaround | Published rush price |
|---|---|---|---|
| A3 Environmental | 3 weeks | 2 weeks; 1 week | +$500; +$1,000 |
| Aegis Environmental | 2-4 weeks | 1-2 weeks | Typically a 20-50% surcharge |
| Geotill | 2-3 weeks | As few as 5-7 business days | Fee applies; amount not published |
| Compyle Environmental | 5 business days ($1,495) | 3 business days | +$400 ($1,895 total) |
A rush compresses the firm’s own queue: the data order, scheduling, desk review and writing. It cannot compress an agency’s response period, the owner’s calendar, the title company or the information only you can provide, so a rush date holds when access, the title commitment and prior reports arrive with the order. Our rush Phase I page covers how the 3-business-day option works.
How long a Phase I takes with Compyle Environmental
Our Phase I ESA is delivered in 5 business days from authorization and confirmed site access with a knowledgeable contact, or 3 business days with a $400 rush. We confirm scope, price and delivery date within 1 business hour, before you authorize.
We built proprietary internal technology that collects and organizes the regulatory and historical records the day an order is authorized, so the EP reviews an organized record instead of assembling one. We book a qualified local field professional at authorization, and the delivery date already accounts for the site visit. Every Phase I is signed by an Environmental Professional who meets 40 CFR 312.10, with reliance for your lender and, for SBA loans, the SBA Appendix 5 reliance letter.
The price is $1,495 flat for standard scope (one parcel, up to 5 acres, up to 3 buildings and 50,000 square feet in total, no heavy industrial or manufacturing use). In October 2026, most Phase I prices and ranges other firms published ran about $1,800 to $5,000, and our Phase I cost guide compares them. If we miss the date we commit to for a reason within our control, we take $250 off. Under our engagement terms, denied or rescheduled access, unavailable interviewees, agency response times beyond our control and scope changes you request extend the date day for day.
Sources
- 2023 Benchmark Survey of Environmental Professionals, LightBox, accessed October 2026
- A Technology Retrospective: The Past, Present and Future of Phase I ESA Tools and Processes, LightBox, accessed October 2026
- EDR’s 2018 Benchmark Survey of Environmental Consultants: Summary of Results, Environmental Data Resources, accessed October 2026
- Lenders, Geotill, accessed October 2026
- Phase 1 ESA: Nationwide, Lender-Accepted Reports, A3 Environmental Consultants, accessed October 2026
- Understanding the Differences Between Phase I and Phase II Environmental Site Assessments, AEI Consultants, March 26, 2025, accessed October 2026
- Phase I ESA Costs and Best Practices for 2025, Aegis Environmental, accessed October 2026
- Phase I Environmental Site Assessment, iSi Environmental, accessed October 2026
- Fast Phase I ESA: From $2,950, Site Visit + 10 Days, FastPhase1, accessed October 2026
- Phase I Environmental Site Assessment, Kross Inspectors, accessed October 2026
- Services, Kross Inspectors, accessed October 2026
- Quote Request, Kross Inspectors, accessed October 2026
- EDR Environmental Data Packages, LightBox, accessed October 2026
- Smart CD, ERIS Environmental Risk Information Services, accessed October 2026
- Environmental Liens and AUL Reports for Phase 1 Assessments, AFX Research, accessed October 2026
- 40 CFR Part 312, Innocent Landowners, Standards for Conducting All Appropriate Inquiries, eCFR, accessed October 2026
- ASTM E1527-21, Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process, ASTM International, accessed October 2026
- Comparison of All Appropriate Inquiries Regulation, the ASTM E1527-13 Phase I Environmental Site Assessment Process, and ASTM E1527-21 Phase I Environmental Site Assessment Process, U.S. EPA docket document (copy hosted by Wisconsin DNR), accessed October 2026
- ASTM Releases New Phase I Standard: What Does It Really Mean for Purchasers?, McGuireWoods, accessed October 2026
- 5 U.S.C. 552, Legal Information Institute, Cornell Law School, accessed October 2026
- California Government Code section 7922.535, California Legislative Information, accessed October 2026
- Florida Statutes section 119.07 (2026), The Florida Senate, accessed October 2026
- New Jersey Revised Statutes section 47:1A-5, Justia, accessed October 2026
- New York Public Officers Law section 89, New York State Senate, accessed October 2026
- Texas Government Code chapter 552, Texas Legislature, accessed October 2026
- How much does a Phase I ESA Cost, Curren Environmental, accessed October 2026
- How Long Does a Phase I Environmental Site Assessment Take to Complete?, Curren Environmental, accessed October 2026
- 42 U.S.C. 9601, Definitions, Legal Information Institute, Cornell Law School, accessed October 2026
- Enforcement Discretion Guidance Regarding Statutory Criteria for Those Who May Qualify as CERCLA Bona Fide Prospective Purchasers, Contiguous Property Owners, or Innocent Landowners (“Common Elements”), U.S. EPA, accessed October 2026
- SOP 50 10 8.1, Lender and Development Company Loan Programs with Technical Policy Updates, U.S. Small Business Administration, accessed October 2026