Public Lab Research note

Colorado Regulations Hotsheet

by gretchengehrke | October 28, 2016 21:41 28 Oct 21:41 | #13664 | #13664

As we start to work with community members in Colorado on issues emanating from oil and gas industry activities, we think it's important to look at the regulatory landscape in the state. Eventually (soon!) we'll build this out into a more in-depth wiki like, (and eventually the Wisconsin regulations wiki will include sections about water quality and the non-metallic mining program). For starters, here is a "hot sheet" about various Colorado state regulations that may be of interest for oil and gas monitoring and advocacy work.

If you're interested in helping build this hot sheet into a thorough explanatory document, please make a comment below! We can work together, and hopefully develop a guide for regulations review in case others would like to do so too. Also, if you're interested in making a hot sheet about another state's regulations, that would be awesome! Please comment, and we can work together on that too!

This research note contains sections on:

Airborne Particulate Matter

Colorado complies with the National Ambient Air Quality Standards (NAAQS) set by the federal EPA, and does not have any more stringent regulations for those criteria pollutants (such as particulate matter) or hazardous air pollutants.

For areas that have been in non-attainment of NAAQS, those counties are subject to special major source emissions limitations, which can be found here:

For any airborne emissions, the state recommends that companies seek control measures that are "technologically feasible and economically reasonable." Note that this is a fairly weak approach for environmental protection, providing a leverage point for industry's economic priorities.

Visible Airborne Emissions

Resources for visible emissions guidelines include:!OpenView&Start=1&Count=30&Expand=1.3#1.3 and

In general, there is a 20% opacity limit for all emissions from stationary sources (such as smokestacks).

In situations where the source doesn't operate for a full six minutes (which is required to satisfy Method 9's 24 consecutive readings at 15-second intervals), then measurements can be taken at 15-second intervals while the source is in operation until 24 readings have been conducted.

There are more lenient opacity limitations for experimental operations (in first 180 days of operation), fire building, and waste gas flares, but these can't exceed 30% opacity for any aggregated six minutes in a 60 minute window.

There is also extra leniency for locomotives, which can have up to 20% opacity at elevations below 6000 ft and 30% opacity at elevations above 6000 ft, and a total exemption for up to 30 minutes upon starting the engine if the locomotive is stationary during that time. There is also leniency during locomotive testing and repair, and acceleration from being stationary for up to four minutes.

For any open burning, companies have to obtain open burn permits and comply with local ordinances, but agricultural vegetative waste that is burned in order to clear fields for crop production is exempted. Companies are supposed to notify any residents that may be impacted by their burning though.

Important exemptions from Colorado's opacity rules include:

  • non-commercial fireplaces and stoves
  • fugitive dust -- airborne dust not directly resulting from man's activities (e.g. windblown dust from a frac sand pile)
  • fugitive particulate emissions -- airborne particulate matter that is due to man's activities (e.g. bulldozing)

Regional Haze

The Colorado Dept of Public Health and Environment, Air Pollution Control Division's State Implementation Plan for Regional Haze:

Federal visibility goals include returning natural visibility conditions (e.g. not impacted by industrial emissions) in Class 1 areas by 2064. Class 1 areas are considered areas of natural and scenic beauty such as national parks; Colorado has 12 Class 1 areas and is part of the Western Regional Air Partnership (WRAP). The initial planning period is 2007-2018 and lays the foundation for further planning and ultimate implementation and attainment. The first planning phase (through 2018) must focus on how the state will improve visibility on the worst visibility days and ensure that the best visibility days remain at current or better visibility.

Emissions sources subject to Best Available Retrofit Technology (BART) requirements must install BARTs no later than 2016. The state must demonstrate how incorporation of BARTs and prevention of significant degradation (PSD) permits will foster "reasonable progress" toward regional haze goals. Note that what is considered "reasonable" includes a balance of economic and environmental considerations.

Phase 1 involves identifying and monitoring "reasonably attributable visibility impairment" (RAVI) to assess existing and new sources' impact on impaired visibility. Colorado is participating in the "interagency monitoring of protected visual environments" (IMPROVE) network, which involves particulate matter source apportionment modeling in conjunction with monitoring at certain sites There are six IMPROVE sites and two additional sites that use IMPROVE protocols in Colorado, most of them clustered in the central northern zone where most of the oil and gas activities are located.

States are required to track and report haze using the Haze Index in "deciview" units, which are calculated from light extinction measurements using transmissometers: (side note: does it seems odd to require everything be reported in a unit than cannot itself be directly measured?).

Colorado's plans include decreasing statewide sulfur dioxide emissions by 51% from 2002 to 2018, including a 91% reduction in sulfur dioxide emissions from Western Regional Air Partnership (WRAP; composed of Colorado and 12 other states) oil and gas sources. Colorado plans to decrease statewide nitrogen dioxide emissions by 30% between 2002 and 2018, but anticipates a 43% increase of NOx emissions specifically from regional oil and gas development. Colorado anticipates a slight (3%) overall decrease in VOCs emissions, but anticipates a 60% increase in VOCs emitted from regional oil and gas operations by 2018. Interestingly, although organic carbon aerosols appear to be the largest driver of poor visibility versus good visibility days, Colorado only anticipates a 1% reduction in organic carbon aerosol emissions by 2018. Colorado expects coarse particulate matter (PM10, particles less than 10 micrometers in diameter) to increase 4% by 2018, in large part due to fugitive dust from building and road construction (which is exempt from visible emissions opacity rules).

Haze-forming pollutants are considered to be PM10, SO2, and NOx (even though VOCs contribute to ozone, which is a leading cause of haze).

Prevention of Significant Deterioration (PSD; rules apply to new sources or modifications of existing sources that cause an increase in emissions by 40 tons/yr SO2, 40 tons/yr NOx, or 15 tons/yr PM10. PSD rules include requiring the emissions source to use the Best Available Control Technology (BACT), construct an emissions model, and conduct ambient monitoring (self-reported). Note that the extent of ambient monitoring that a site would need to do once operations have begun to demonstrate compliance with PSD is subject to what the reviewing authority (Colorado DPHE) deems necessary to assess that source's effect on ambient air quality.

Colorado is not on track to achieve the natural visibility conditions by 2064 in most of their Class 1 areas. New estimates for achieving those visibility conditions range from 2083 to 2168.

Hydrogen sulfide

Air permits (Air Pollutant Emissions Notice, APEN) must be obtained for sources that will emit more than 2 tons per year H2S in an attainment area or 1 ton per year H2S in a non-attainment area. A step-by-step guide for figuring out if you need to apply for an air permit can be found here.

Before building a new emissions source, air permits are required for construction activities in Colorado if the company estimates they will emit 2 tons per year of H2S, or more. However, sources that involve combustion of natural gas containing "trace" H2S of less than 500 ppm (which is not an insignificant amount, health-wise) are exempt from requiring construction permits.

Effluent Turbidity

Information about stormwater and discharge permits in Colorado can be found on the CDPHE website:

Stormwater turbidity

Non-point source potential polluters (such as agricultural operations) are encouraged to use best management practices, but that is entirely voluntary.

Point-sources of pollution, like industrial operations, do have to comply with stormwater permits. Interestingly, oil and gas operations have an exception if the stormwater hasn't come into contact with overburden materials, raw materials, products or byproducts. Note that the owner/operator of the facility doesn't have to apply for a permit unless the discharge does come into contact with the material, but without a permit and requisite monitoring, it's unclear how CDPHE would be able to assess whether or not the stormwater came into contact with those materials, except possibly through site inspections or aerial photography. Specific stormwater permit types for various industries (mostly general permit, COR900000) can be found here.

Direct effluent turbidity

There are several regulations that address direct effluent, and these regulations need to be unpacked in a more in-depth review. Here are some general notes (that I think are poignant), and a list of links to Colorado water quality regulations is included below.

One important note is that it appears as though permitees (not the DPHE) are responsible for assessing, reviewing, and analyzing their self-monitoring and self-reported data.

Total Suspended Solids (TSS) in direct effluent/discharge is not to exceed 45 mg/L for a 7-day average of samples, and not to exceed 30 mg/L for a 30-day avg of samples. If a treatment pond is the primary strategy for secondary treatment of waste, then the 7-day average of TSS can be up to 160 mg/L and 110 mg/L for non-aerated and aerated treatment ponds, respectively, but both types need to have an 85% TSS removal before discharging into state waters.

Nutrient effluent limits appear to be based solely on total phosphorus and total inorganic nitrogen.



This is cool!

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