Air Monitoring in North Denver (CAG Overview) Environmental Quality - - PowerPoint PPT Presentation

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Air Monitoring in North Denver (CAG Overview) Environmental Quality Division Department of Public Health & Environment July 17, 2018 Denvers s N Nationally lly A Accredited P Publi lic H Healt lth D h Department CONNECT WITH

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Denver’s ’s N Nationally lly A Accredited P Publi lic H Healt lth D h Department CONNECT WITH US 311 | POCKETGOV | DENVERGOV.ORG | DENVER 8 TV

Air Monitoring in North Denver (CAG Overview)

Environmental Quality Division Department of Public Health & Environment July 17, 2018

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Requested Discussion Topics

► Overview of monitoring ► Air monitoring data network management

► Swansea Air Monitoring Data

► Elevated Pollution Days

► Labor Day weekend 2017 (Sept 4 in particular) ► November 10, 2017 ► January 4, 2018 ► February 22, 2018

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Projects Overview

 Globeville Landing Outfall  Central 70  OU1, OU2, OU3  Four air quality monitoring projects

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Swansea Air Monitoring Station

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Goal: Develop a better understanding of ongoing cumulative air quality impacts associated with major highway construction

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Measures Pollutants:

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CO, NOx, PM2.5, PM10, Black Carbon, VOC’s

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Frequency: Minute for criteria pollutants, 5 min BC, 30 min VOC’s

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Collaborators:

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Denver Department of Public Health & Environment

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Colorado Department of Transportation

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Colorado Department of Public Health and Environment

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Schedule:

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Start: April 1, 2017

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End: 1 year after end of construction (there will be future phases during and after construction)

425 ft 260 ft

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Network Management

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Data – PM Focus

PM10 STD PM2.5 STD

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CO NO2 PM2.5 PM10 BC

Report View

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Elevated Pollution Days

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Elevated Pollution Days in Denver

Key ingredients

In Denver’s case, river valley next to mountains
Cold air is more dense and sinks into the valley
Temperature inversions (occur year round, strongest in fall

and winter)

Clear skies (night) or high clouds (day) that partially block the

sun

Light or stagnant winds
Wildfire smoke (summer and fall)
Enough terrain variation in Metro Denver that high pollution is

frequently but not always Metro-wide

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Temperature Inversions

Inversions act as a lid on the atmosphere
With surface heating after sunrise,

inversions usually break by mid morning

Mobile source pollution gets trapped

below the inversion

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High Pollution Days over Past 12 Months

Labor Day weekend 2017 (Sept 4 in particular)
November 10, 2017
January 4, 2018
February 22, 2018
Without wildfire impacts, PM levels greatest in winter, followed by

fall, summer, and spring in that order

Need to evaluate regional monitors to determine if it is a regional or

local event

Visibility cameras and new satellite images are helpful as well

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September 4, 2017 (Labor Day)

Heavy smoke from Pacific NW

wildfires

Impacts over entire weekend
Peaked on Labor Day behind

a dry cold front

Due to holiday, clearly not a

mobile or industrial source driven event

All 4 GLO monitors high as

well

Regional impact from Fort

Collins to Chatfield

Longmont Boulder Chatfield

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Sept 4, 2017 (Labor Day) – Wildfire Smoke

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Sept 4 2017(Labor Day)– Visibility Camera

Can’t see the mountains!

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November 10, 2017

All day inversion
Greater impacts in the

S Platte River valley from Denver-Greeley

Greeley 24-hr Avg = 35

(not shown on map)

Typical urban pollution

sources all contributing

Longmont Boulder Chatfield

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Nov 10 2017– Visibility Camera

Can barely see the mountains; highest PM near the surface

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January 8, 2018

All day inversion
Highs temps mid 40s
Greatest impacts in the S

Platte River valley Denver- Greeley

Greeley 24-hr Avg = 35 (not

shown on map)

Boulder, Longmont, and

Chatfield are not in the inversion or as long

High clouds all day until ~2 pm
Sun could not heat surface

and erode the inversion

Longmont Boulder Chatfield

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Jan 8 2018 – Visibility Camera

Strong, shallow inversion impacting ground level monitors.

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February 22, 2018

All day inversion
Greatest impacts in the S

Platte River valley from Chatfield-Greeley

Greeley 24-hr Avg = 30 (not

shown on map)

High temps low-mid 20’s
Cloudier as day went on
Light snow by 4 pm
Sun could not heat surface

and erode the inversion

Longmont Boulder Chatfield

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Feb 22 2018 – Visibility Camera

Cant see the mountains, 60% humidity and aerosols (PM) making for ext. poor visibility