This past Wednesday, April 26th, 2017, I attended a Puget Sound Clean Air Agency (PSCAA) information session on two permits for expanding fossil fuel operations in the Port of Tacoma.

Permit #1:  Emerald Services proposes to expand their capacity to refine used motor oils by 10%.  Per questioning during the session, this will equate to an approximately 5,000 gallon increase per day.

Permit #2:  Targa Sound Terminal seeks to modify four existing storage tanks to be able to house natural gasoline (a liquid byproduct of natural gas extraction).  Targa is anticipating that they will receive approximately 3 x 36 rail cars per week of natural gasoline.  By simple math, this equates to approximately:

 3 trains/week x 36 railcars/train x 30,000 gallons/railcar
          = 3,240,000 gallons of natural gasoline / week

So Targa will be bringing in about 3.24 million gallons of natural gasoline to the port per week.  Per Targa’s permit (p. 2-1), the annual throughput at the terminal of the natural gasoline will be 151,500,000 gallons/year.  Also per the permit, these four tanks have only been used to store distillate products such as diesel and fuel oil.  It is unclear, however, if these tanks are currently being used or if this represents an actual increase in the amount of fossil fuels being introduced by Targa into the Port of Tacoma.

There is plenty to discuss about the merits of the two proposed permits, however I want to focus the remainder of this blog entry on some comments made by the PSCAA representatives.  PSCAA indicated that the air quality ramifications of these permit requests are only considered on a permit-by-permit basis, and that the impact of these permits on the overall air quality is not considered during the permit review process.  So consider the case of benzene release (note that benzene causes cancer per the American Cancer Society). It was discussed that Targa’s introducing natural gasoline would actually increase the amount of benzene released in the atmosphere and PSCAA provided hardcopy slides showing a benzene wind dispersion model around the Targa facility (see Figure 1).  The PSCAA representative indicated that when reviewing the permit, that they only consider the specifics of that permit, and not how it impacts the overall air pollutant levels.  This is disturbing as what if by approving the Targa application, that the overall benzene level in the Port of Tacoma reaches a toxic level for humans?  Shouldn’t this overall benzene level be regulated and doesn’t it make sense that PSCAA should be the regulatory agency?

Figure 1: Targa Sound Terminal Benzene Wind Dispersion Model Results (picture of slide provided by PSCAA)

In reviewing PSCAA’s website, they indicate that they currently monitor six pollutants, what they call “criteria air pollutants” which include:

  1. Particle Pollution
  2. Ozone
  3. Carbon Monoxide
  4. Sulfur Dioxide
  5. Nitrogen Dioxide
  6. Lead

Pollutants levels of items 3-6 are apparently significantly below the federal requirements, so while concerned about them, PSCAA doesn’t appear to be actively working to further reduce them.  Items 1 and 2 are still of concern however.  The next obvious question then becomes (at least to me):  what particle and ozone sensors does PSCAA operate in and around Tacoma, and in particular around the heavy industrial Port of Tacoma?

During the meeting, PSCAA indicated that they have only a single air quality sensor in the Port of Tacoma.  This sensor measures fine particulate matter (PM2.5) (i.e. item 1 above).  These are very small particles that measure approximately 2.5μm in size.  PSCAA provides a nice description and the below graphic of particulate matter.

Figure 2: Particulate Matter Sizes (PSCAA)

It is unclear to me if the existing PM2.5 sensor in the Port of Tacoma also measures ozone levels or not, but I’m guessing that it does not.  Noticeably absent is a benzene sensor, especially given the potential increase in benzene due to the Targa natural gasoline project.  I would note that PSCAA currently operates three air quality sensors in and around Tacoma, per their website (it appears that they actually have four sensors, but one of them only collects temperature and wind data) (see Figure 3 or

  1. Tacoma S 36th
  2. Tacoma South L
  3. Tacoma Tideflats

Figure 3: PSCAA Air Quality Sensor Locations (source:

With all of this as background, where does that leave us?  It appears that PSCAA currently operates by providing permits without consideration for cumulative air pollution levels for most pollutants and that PSCAA has very limited air quality sensors in and around Tacoma, which raises my final question:

Shouldn’t we be measuring a greater number of pollutants beyond just the criteria air pollutants around Tacoma to ensure high quality air?

Questions and Follow-up:

  1. Targa – Does the 3.24 million gallons of natural gasoline per week represent an increase in the amount of fossil fuels that you will be bringing into the Port of Tacoma, or is Targa substituting this natural gasoline for another fossil fuel?  If the latter, please indicate which other fossil fuel you are reducing and by how much?  What is the net increase / decrease in pollutant emissions
  2. Cumulative Air Quality Monitoring of Additional Pollutants – I believe that we need to advocate that PSCAA expand the scope of their cumulative air quality monitoring to include other pollutants such as benzene, carbon dioxide, methane, and more.  We obviously need to define what this list should include.



John C · April 30, 2017 at 5:42 pm

TY for posting. Alarm bells should be going off for those who live nearby…

Steven Storms · May 1, 2017 at 3:18 pm

Another point that PSCAA does not address is the difference in safety from the change in fuels arriving and stored in the tanks. The “natural gasoline” is described as isopentane. This is a highly volatile chemical and is much more dangerous than diesel or fuel oil. Bringing in 107 rail tanker car per week and shipping it out by marine vessels should be a safety consideration. Since it is not a clean air problem, PSCAA does not address this issue when issuing a permit. Either their role needs to be expanded or the process needs to include other agencies that can properly evaluate safety risks.

Steven Storms · May 1, 2017 at 4:20 pm

Emerald Services also points to the flaw in having PSCAA be the authority to grant permits. While PSCAA is directly involved with clean air, they do not have the authority to look at other environmental issues. Emerald Services has one of the worst environmental records in the State. They were fined $167,000 in 2015. They were investigated for 19 spills in 2015 and over 200 since 2008. “We don’t keep a master list of who commits the most spills in the state, but they’d be in the top five,” says Department of Ecology spokesman Chase Gallagher. – Granting an expansion to a company with this environmental record should not even be considered. If PSCAA is to be the permitting agency, they need the authority to investigate more than just air emissions.

Mary Paterson · November 10, 2017 at 1:52 am

I am reading this blog for the first time out of concern about the LNG plant currently under construction at the Port of Tacoma. I live in Seattle but my daughter, an environmental engineer, lives in Boulder. Here is an paper she recently wrote on small-scale sensors in the Boulder area that showed oil and gas extraction as a cause of high levels of surface ozone:
the press release-summary is

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