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Prescribed fire EPA monitor flag

2021-03-10 Augusta-Richmond County prescribed-fire smoke episode

March 10, 2021 · Origin: Augusta-Richmond County, GA-SC

Daily PM2.5 peaked at 41.2 µg/m³ near Augusta across 1 covered metro home to 636,760 people.

Why we think this happened

The basis for “Prescribed fire”

Supplied qualified evidence supports prescribed-fire smoke as the root cause. The grouping includes only events linked by explicit shared episode evidence; otherwise this remains a single-event episode.

EPA monitor flag EPA attached an exceptional-event qualifier to the affected samples. The agency flagged the measurement itself; no separate agency record describes the event.

U.S. EPA Air Quality System and the submitting air monitoring agency · Mar 10, 2021 official

AQS PM2.5 qualifier RM — Prescribed Fire.

EPA AQS carries an agency-submitted request-exclusion qualifier (RM, Prescribed Fire.) on 48 PM2.5 samples in the candidate CBSA on 2021-03-10, identifying prescribed-fire smoke as affecting the samples. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.

See every retained source and limitation ↓

Evidence path

From source to city

A cause is more convincing when the record connects three things: something happened, the air mass moved toward the region, and local instruments responded. Here is how much of that chain is documented for this event.

Open the evidence ledger ↓
  1. 1

    Source or mechanism

    Prescribed fire

    EPA AQS carries an agency-submitted request-exclusion qualifier (RM, Prescribed Fire.) on 48 PM2.5 samples in the candidate CBSA on 2021-03-10, identifying prescribed-fire smoke as affecting the samples. A request-exclusion qualifier is an official…

    View supporting source ↗
    Documented
  2. 2

    Air-mass movement

    The transport path has not been reconstructed

    The retained record does not yet show how air traveled from the proposed source to these metros. A trajectory replay or dated plume analysis belongs here.

    Research gap
  3. 3

    Local response

    41.2 µg/m³ near Augusta

    EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.9 cigarette-equivalents at the outdoor daily rate.

    Inspect the pollutant and weather signals ↓
    Documented

Event autopsy

What the instruments saw

Before, during, and after the episode: nearby pollutant monitors and surface-weather stations show what changed. This context tests the “Prescribed fire” explanation; it does not assign the cause by itself.

Observed context · not attribution

Augusta-Richmond County, GA-SC

Monitor comparison window 2021-03-07 to 2021-03-13 · PM2.5 target: Augusta

4 pollutant signals
Fine-particle pulse 40.5 µg/m³

115% above nearby days

Air movement 1.76 kt

17% higher than surrounding days

PM10 27 µg/m³

42% higher than surrounding days

Pollution fingerprint

Metro-wide median of reporting monitors
PM2.5 40.5 µg/m³

115% higher than surrounding days

Before16.4 µg/m³ Event40.5 µg/m³ After18.8 µg/m³
1 monitor · 1 HOUR
PM10 27 µg/m³

42% higher than surrounding days

Before14 µg/m³ Event27 µg/m³ After19 µg/m³
1 monitor · 24-HR BLK AVG
Sulfur dioxide 0.179 ppb

About the same as surrounding days

Before0.196 ppb Event0.179 ppb After0.096 ppb
1 monitor · 1 HOUR
Ozone 0.040 ppm

About the same as surrounding days

Before0.035 ppm Event0.040 ppm After0.039 ppm
4 monitors · 8-HR RUN AVG BEGIN HOUR

Atmospheric conditions

Nearby EPA weather observations
Humidity 60.5 %

About the same as surrounding days

Pressure 1026 Millibars

About the same as surrounding days

Temperature 56.7 °F

About the same as surrounding days

Wind 1.76 kt

17% higher than surrounding days

Source: U.S. EPA AirData daily observations and, where available, nearby ASOS/AWOS surface observations. Values are descriptive medians over the retained monitor set; missing measurements remain missing. Transport and source evidence remain separate layers because this instrument pattern does not assign a cause by itself.

Measured daily PM2.5 at EPA monitors, as cigarette-equivalents
EPA monitors sit in metro areas, so the colour clusters there. Land between and beyond them is unmeasured, not clean: this map shows where IAQng has readings, not the extent of the smoke.

Episode peak

-- cigarettes

The smoke map's scale, replayed over this event: the surface interpolates between covered metros' daily records, framed to the affected region. Hover for a reading, click a metro to pin it to the card. Days a monitor did not report draw nothing.

Affected metros

MetroPeak PM2.5Cigarettes, whole eventPeak dayAll-time standing
Augusta-Richmond County, GA-SC 41.2 µg/m³ 1.9 Mar 10, 2021 #25 of its top days

"Cigarettes, whole event" totals a metro's ranked event days at 22 µg/m³ per cigarette: what a person outdoors there breathed across the event, as the illustration. "All-time standing" is where this episode's days sit in each metro's ranked record (worst-area measure, since 1999). Full local context is on each metro's Air Records page.

Public evidence library

What supports this account

Each card states what a source supports—and what it does not. Official records, research, reporting, community observations, and transparent inferences remain visibly different kinds of evidence.

EPA AQS monitor qualifier 1

  • AQS PM2.5 qualifier RM — Prescribed Fire.

    U.S. EPA Air Quality System and the submitting air monitoring agency · Mar 10, 2021 official government

    EPA AQS carries an agency-submitted request-exclusion qualifier (RM, Prescribed Fire.) on 48 PM2.5 samples in the candidate CBSA on 2021-03-10, identifying prescribed-fire smoke as affecting the samples. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.

Agency and publisher pages 1

  • Final Report for PM2.5 Exceedances in Georgia, 2021

    Georgia Environmental Protection Division · Georgia Environmental Protection Division official government

    The state report lists the Augusta monitor's March 10, 2021 PM2.5 exceedance (41.2 µg/m3) and attributes it to prescribed fires.

What remains uncertain

Status and provenance

EPA monitor flag EPA attached an exceptional-event qualifier to the affected samples. The agency flagged the measurement itself; no separate agency record describes the event.

This episode was grouped from the monitor record by the catalog pipeline and given its cause from the evidence listed above. It has not been individually reviewed and signed off, so its boundaries, cause, and name may change as evidence accumulates. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula. If it is wrong, tell us.