Monthly audits, reviewed with the crew the next day
No California electric safety rule sets an interval for auditing completed vegetation work. The utility sets it, in its wildfire mitigation plan and its contract, and Energy Safety audits that commitment. A monthly cycle is chosen because the evidence a span leaves behind decays in weeks. The next-day review reaches the crew that made the cut.
A vegetation QA/QC program has two clocks. One decides how often the auditor walks completed work. The other decides how long a finding sits before the people who made the cut hear about it. Most published program documents set the first and say nothing about the second, which is how a program ends up with a year of audit results and no change in the defect that produced them.
This page is about those two intervals: where the numbers come from, what a month buys that a quarter does not, and which findings are not permitted to wait for either clock. What the auditor grades once on site belongs to what a QA/QC audit actually covers.
The code does not set the interval
No California electric safety rule tells a utility how often to audit completed vegetation work. What the state reaches is the commitment the utility made in its own plan. California Public Utilities Code section 8386.3(b)(5)(A) puts it plainly:
Following the end of the performance period, the office may, consistent with its authority pursuant to paragraph (1) of subdivision (b) of Section 15475 of the Government Code, conduct audits of the vegetation management work performed by, or on behalf of, the electrical corporation. The initial audit shall identify deficiencies in the electrical corporation's implementation of the vegetation management commitments in the wildfire mitigation plan.
The measuring stick is the plan. Subparagraph (B) adds that the office may engage its own independent auditor, who "shall be a certified arborist." So the person checking the interval is qualified to walk the span it produced.
Energy Safety has used it. On April 13, 2022, the office sent Southern California Edison its audit report on SCE's substantial vegetation management work in 2020. The letter cites section 8386.3(c)(5)(A); the audit authority reads at subdivision (b)(5)(A) today, so a reader who opens the 2022 letter and goes looking for (c)(5)(A) in the current code will not find it.
The practical answer to "who sets the interval" is therefore the utility, twice. Once in the wildfire mitigation plan, where the number becomes a commitment the state can audit. Once in the contract, where it becomes a thing somebody is paid to do.
Three published answers to when the auditor goes out
Utilities have solved this differently, and all three of these are public.
Program | What triggers the review | Source |
PG&E distribution vegetation QC | A work order packet with all spans 100 percent inspected and 85 percent or more of prescribed tree work completed and documented | |
PacifiCorp overhead detailed inspection audits, Tier 1 | A computer-generated random 5 percent sample inside a completed section, weekly | |
PacifiCorp vegetation management QA/QC, as documented for 2025 | Forester discretion |
PG&E's document declines to name a calendar at all:
The timeliness of QC reviews is dependent on the VM program being evaluated and the specific execution work activity.
Its trigger is a completion percentage rather than a date. Quality control reviews a distribution work order packet once the packet is fully inspected and 85 percent of its prescribed tree work is done and recorded. Annual planning still happens on a calendar. The document reads: "Planning is conducted in the fourth quarter of each year for the following year." The audit itself waits for the work to reach a threshold.
PacifiCorp's asset inspection side runs the other way. Contractors audit a random 5 percent sample weekly, drawn inside a completed section. That program is pole and equipment inspection rather than vegetation work, so it is not a vegetation benchmark. It is useful as a comparison, because the same evaluator looked at both programs at the same company in the same report and graded them differently.
The interval is what the evaluator grades
The third row of that table is the one worth reading twice. On page 124 of the 2025 report, the Independent Evaluator wrote:
The materials describe QA/QC as occasional and left to the foresters discretion, which conflicts with the 2025 WMP's statement that post-audits occur annually
Two documents at one utility named two different intervals, and one of the two was forester discretion. The evaluator's finding lands on the conflict itself. A program that cannot state its own cadence gives an auditor nothing to measure against.
Energy Safety's evaluator scores QA/QC on five dimensions from 0 Not Implemented to 4 Mastered. On the Quality Inspections/Audits dimension, frequency is written into the rating itself:
Rating | Frequency of subject matter expert review of inspection quality | What is done with results |
2 Applied | At least annually | Reviewed to make ad hoc corrections |
3 Routine | At least twice per year | Used to identify deficiencies and weaknesses |
4 Mastered | At least four times per year | Used to improve WMP processes, procedures, and trainings |
PacifiCorp scored 2 on that dimension in 2025. The top of the published ladder is four reviews a year. A monthly audit cycle is twelve, and it clears the frequency half of a 4 rating three times over.
The second column is the one that actually separates a 2 from a 4. At a 2, results are "reviewed to make ad hoc corrections." At a 4, they are "used to improve WMP processes, procedures, and trainings." That distinction is a statement about who hears the finding, not about how often the auditor walks.
What a month buys that a quarter does not
Take one span. A crew prunes poles 47 to 48 on a distribution circuit on March 4. Under a monthly cycle the auditor is under that span by March 26, twenty-two days later. Under a quarterly cycle the same span is audited on June 20, one hundred and eight days later.
By June 20, five things the auditor needs are gone or degraded:
The regrowth has moved the number. The clearance the auditor measures in June is not the clearance the crew left in March. How much it moved depends on the species and the season, which are worked through in growth rate and cycle length and fast-growing species. Which of those two numbers the auditor is grading is settled in time of trim versus maintained clearance.
The brush is gone. A cleanup finding is graded against a site that was hauled the same week. Most BMP failures leave the site before the auditor arrives, which is why site clean and BMPs grades the record as much as the ground.
The mark has weathered. Paint on a trunk is evidence of what was prescribed, and it is evidence with a shelf life. What that mark is worth is covered in trim type correct.
The crew has moved. Three months of production puts a distribution crew on a different circuit, often in a different district. Sending them back to poles 47 to 48 is a remobilization, and the person who pays for it is the subject of rework.
Nobody remembers the span. A foreman can tell you in March why a limb was left, and which customer said no. In June the answer is a shrug, and a refusal that was real becomes a defect that is undocumented.
Monthly does not eliminate any of that. Twenty-two days of regrowth is still regrowth. It keeps all five inside the window where an answer still exists.
One statutory clock runs on the same rhythm and is easy to miss. Under 3 CCR 6627, the monthly summary pesticide use report is due to the county agricultural commissioner by "the 10th day of the month following the month in which the work was performed."
An audit that closes out March in the last week of March gives the herbicide record a few days of usefulness before it is filed. An audit that closes out March in June is reviewing a report the county already has. The record itself belongs to site clean and BMPs.
The month is a lot boundary, and the boundary is a timestamp
The interval does more than schedule a visit. It draws the edge of the population the sample is pulled from. March's audit covers units that closed in March, so the closure timestamp decides which audit a unit belongs to.
That edge is sharper than it sounds. Two spans on the same line, cut by the same crew on the same afternoon, can land in different months: one closed at 4:50 p.m. on March 31 and one at 7:10 a.m. on April 1. They are graded by different auditors against different monthly rates, and a defect common to both shows up twice in two reports rather than once as a pattern.
Which event the completion date names is the whole question here. The day the crew finished, the day the paperwork went in, and the day a reviewer signed are three different dates on one unit, and they are set out in unit closed properly. For the interval, the rule is narrow. The program picks one event, writes it down, and uses the same one every month. A program that changes which timestamp defines the month has made its month-over-month trend meaningless.
How the sample is drawn once the lot is defined, and what has to be recorded for it to stand up later, is sampling versus a full census.
Short months make noisy rates
A monthly interval has a real cost, and it is arithmetic rather than money.
Suppose a contract produces 40 work units in March and the plan samples 5 percent of them. That is 2 units. One failing unit prints a 50 percent fail rate for March. Run the same contract for twelve months at that rate and the year holds 480 units, of which 24 are audited. The same single defect against 24 audited units prints 4.2 percent. Nothing about the work changed between the two figures. The denominator did.
Two things follow, and a program should do both.
1. Act on findings monthly. A defect found on March 26 is actionable on March 27 regardless of what the rate says. 2. Read the rate on a rolling window, or set a floor on the monthly sample so the denominator cannot collapse. A three-month rolling pass rate moves on the work. A two-unit monthly pass rate moves on one span.
Reporting both is honest and takes one more column. Reporting only the monthly rate invites a program to celebrate a 100 percent month that was two units.
The next day: who actually hears the finding
The monthly review most utilities can document is a meeting between the utility and the contractor's management. SCE described its version to Energy Safety:
SCE's vegetation management and supply management personnel meet monthly with all of our vegetation contractors in separate meetings…[to] [discuss] including, but not limited to, quality control and adherence to schedule.
Energy Safety did not take that sentence at face value. It asked for proof and got one artifact: a May 2020 scorecard reviewed with a vegetation contractor, listing areas "needing improvement," one of which was quality of work pertaining to SCE's vegetation radial clearance distance. The auditor accepted the scorecard, and on that basis found SCE consistent with its plan.
That meeting is a program-level review. It reaches a general foreman and a contract manager. It does not reach the sawyer who made the cut on poles 47 to 48, and a defect in how a cut is made is fixed at the saw.
The next-day review is the other half. The finding from March 26 goes to the crew at the March 27 tailboard, with the span number, the photo, and the specific call. Three properties make it work:
It is the same crew. The people who will make the next cut, rather than the contractor's office or the district.
It is specific to a span. "Clearance on 47 to 48 came in at 3 feet 8 inches against a 4-foot requirement" changes behavior. "Clearance scores are trending down" does not.
It is early enough to matter. A crew working a monthly cycle has roughly twenty more production days in the audit month after the review. A crew hearing a March finding in June has already built the same defect into three months of work.
PacifiCorp's approach is a system push rather than a meeting: audit exceptions are recorded in its Mobile Data Management Software and, per the 2025 report at page 125, "the audit exceptions are visible to the vegetation management contractors within the MDMS." Visibility in a system and a conversation at a tailboard are not the same event. A program that relies on the first should be able to show that somebody opened it.
A safety finding does not wait for either clock
This is where the interval stops being a scheduling question.
An auditor walking completed work sees two kinds of thing. One is a quality defect in the finished product: a clearance short of the number, a flush cut, brush left in a ditch. Those belong to the monthly sample and the next-day review. The other is an unsafe work practice observed in progress: a climber inside the minimum approach distance, a drop zone with a road in it, a chipper fed with the guard defeated.
The second kind is governed by 8 CCR 3203, which binds every employer in California, and it runs on severity rather than on a calendar. Subsection (a)(6) requires an injury and illness prevention program to:
Include methods and/or procedures for correcting unsafe or unhealthy conditions, work practices and work procedures in a timely manner based on the severity of the hazard: (A) When observed or discovered
"When observed or discovered" is the clock. A QA auditor who logs an approach-distance violation for the March report and leaves the crew working has not met it. Approach limits themselves are covered in Cal/OSHA 2950 and minimum approach distance; who may halt the work is part of who signs off on a span.
Two further subsections attach to the same finding. Section 3203(a)(4)(C) requires inspections to identify and evaluate hazards "[w]henever the employer is made aware of a new or previously unrecognized hazard." Section 3203(a)(7)(E) requires training and instruction on the same trigger. So an audit finding that surfaces a previously unrecognized hazard obliges a look and a training response, and neither is satisfied by a line item in a monthly report.
Where a QA auditor has authority to stop work, and where that authority sits with somebody else, is a contract question with a real answer in each program. It should be answered before the auditor is in the field rather than in the moment.
What the two intervals have to leave behind
What Energy Safety accepted as proof was an artifact: one scorecard, from one month, naming one deficiency. That sets the standard for both clocks. A stated interval with no monthly artifact behind it is the exact gap the 2025 PacifiCorp finding names.
A monthly audit cycle produces, each month:
The lot definition: which units closed in the month, under which timestamp rule.
The sample: which units were drawn, how, and by whom.
The findings, each tied to a unit and a defect class.
The rate, stated with its denominator and alongside the rolling figure.
A next-day review produces, for each session:
The date, the crew, and who was present.
The spans discussed, by identifier.
The specific call on each, in the terms the auditor used.
What the crew disputed, if anything, and who resolved it.
That last line is the one programs leave out and the one that earns the review its keep. A crew that pushed back on a clearance call and was right has found a calibration problem between two auditors, which is worth more than the span. A crew that pushed back and was wrong has been trained, which is what the 4 rating on the Energy Safety ladder asks for.
Retention of both sets of records is covered in recordkeeping and retention. What happens to the failed unit after the crew has heard about it is rework.
Further reading
What a QA/QC audit actually covers in utility vegetation work: The unit under audit, the corrective action, and the due date the finding carries.
Sampling versus a full census: How the sample is drawn inside the month, and what makes it defensible afterward.
Rework: what happens to a failed unit, and who carries it: Where a finding goes once the crew has heard it.
Frequently asked questions
Does any California rule say how often a QA/QC audit of completed vegetation work has to happen?
No rule sets a fixed interval for it. Public Utilities Code section 8386.3(b)(5)(A) lets Energy Safety audit vegetation management work performed by or on behalf of an electrical corporation, and the standard that audit applies is the corporation's own wildfire mitigation plan commitments. So the interval is set in the plan and in the contract, and the state then measures the utility against the number it wrote down.
What does Energy Safety's independent evaluator use to grade audit frequency?
A five-dimension QA/QC framework scored from 0 to 4. On the Quality Inspections/Audits dimension, the 2 rating requires inspection quality assessed through subject matter expert review at least annually, the 3 rating at least twice per year, and the 4 rating at least four times per year. In the 2025 PacifiCorp report the evaluator scored that dimension a 2.
Why review the audit with the crew the next day instead of at the monthly contractor meeting?
The monthly meeting is a program-level review between the utility and the contractor's management, and Energy Safety has accepted a monthly scorecard as evidence that one happened. It does not reach the foreman who made the cut. A next-day review does, while the crew still remembers the span and is close enough to go back to it.
Can a safety finding wait for the monthly review?
No. Title 8 section 3203(a)(6) requires correcting unsafe work practices in a timely manner based on the severity of the hazard, when observed or discovered. The audit calendar governs the quality sample. It has no bearing on a finding about how the work was performed.
Is a monthly pass rate a usable number?
Not on its own when the monthly lot is small. A 5 percent sample of a 40-unit month is 2 units, so a single failure prints a 50 percent fail rate. Act on the findings monthly and read the rate on a rolling window, or set a floor on the monthly sample size.
