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Odors & Hydrogen Sulfide

DEC conducted a screening assessment to look for sources of odors in the Port of Albany (Port). A variety of odorous chemicals can be released from industrial sources and standard air sampling methods are not designed to measure most of these chemicals. Additionally, there are a few chemicals that people can smell at levels below our ability to measure them. This makes pinpointing the exact cause of odors and a source for odors challenging. One of the common odorous chemicals related to many of the industrial activities in the Port is hydrogen sulfide. Because DEC has instruments capable of measuring hydrogen sulfide at low levels, this chemical was used as a surrogate for investigating sources of odors. Staff measured hydrogen sulfide in the Port in 2015, 2016 and 2017. Hydrogen sulfide has a noxious odor like "rotten eggs". The screening for sources of odors was conducted during the warmer months, May to November, when hydrogen sulfide levels were expected to be higher.

Where?

Hydrogen sulfide monitors rotated through eight locations in the Port area and each monitoring session lasted for a full week. These locations, shown on the map, are close to potential sources of hydrogen sulfide and industrial activities with known odors. Locations were sampled multiple times, from May to November.

Map showing the locations where air monitoring sessions took place in the Port area.

Instrument

The type of monitoring instrument used is an Apptek Low Range OdaLog. The instrument's operating range is 0.01 to 2.00 parts per million (ppm). Data were collected at ten-minute intervals and the results were stored in the instrument and downloaded after a week of monitoring. The instrument is an effective screening tool for understanding sources of hydrogen sulfide and changes in concentrations. It is battery operated and can be placed along public roads between industrial facilities. The results are collected on a continuous basis, so if there are significant and consistent sources of hydrogen sulfide they will be detected no matter when the emissions occur - day or night. There are limitations with this instrument. Diesel exhaust and other common gases such as carbon monoxide, nitrogen oxides and sulfur dioxide can interfere (by increasing the apparent hydrogen sulfide concentration) with the accuracy of the hydrogen sulfide results. Therefore, this instrument cannot be used as an enforcement tool.

Air Standard for Hydrogen Sulfide

DEC's standard for hydrogen sulfide is 0.01 ppm for a one-hour period. Because of the limitations of the instrument, results will be compared against the State standard to determine follow-up activities but not enforcement actions.

Results

Over the course of the study, 80,000 ten-minute observations were collected. During the study, almost all the results were below the instrument detection limit (0.01 ppm) - hydrogen sulfide was rarely detected. The results were at or above the detection limit for 172 observations (0.22%). As shown in Table 1, on eight separate occasions one-hour averages (calculated by averaging six consecutive ten-minute concentrations) were above DEC's one-hour standard for hydrogen sulfide. All of them were consistently at location #5 near the Buckeye Terminal. The intermittent nature of the results at location #5 indicates that a source of hydrogen sulfide is in the localized area. Known sources of hydrogen sulfide clustered in this area include an asphalt plant and diesel emissions from trucks and equipment, including marine vessels which generally do not use low sulfur fuels. Since the exceedances were separated by weeks, intermittent operations of diesel engines could be the likely source of these measurements.

Although the tool we used in this screening assessment did not detect hydrogen sulfide very often, very low levels of hydrogen sulfide could be present and some people can smell it below the instrument's detection limit.

Table 1. Hydrogen Sulfide 1-hour Averages above State Standard at Location #5
Date Time 1-hour
Average (ppm)
5/23/2016 6:53 AM 0.013
7/5/2016 12:11 PM 0.028
8/18/2016 11:31 AM 0.062
9/15/2016 1:41 PM 0.012
9/26/2016 2:13 PM 0.10
9/28/2016 1:03 PM 0.030
10/13/2016 8:19 AM 0.022
10/03/2017 2:11 PM 0.018

*New York State Standard for hydrogen sulfide is 0.01 ppm.

Next Steps

Although this screening assessment did not identify any sources at the Port that we would consider to be large sources of hydrogen sulfide, there are a variety of industrial operations in the Port that release odorous chemicals. DEC will continue to evaluate these operations and research other tools for investigating sources of odors in the community.

We recognize that there is still a concern for hydrogen sulfide odors. We will continue to use our screening instruments for evaluating sources of hydrogen sulfide in this community and monitor changes in facility operations that could contribute to increased releases of hydrogen sulfide.

Odor Hotline

Report nuisance odors 1-800-457-7362 toll-free 24-hour hotline.

DEC will conduct on-the-spot air quality inspections using portable air monitoring equipment to assess the odor issues and help identify the cause in response to complaints.

More about Odors

To learn more about odors and health effects visit these sites.

New York State Department of Health - Odors & Health (leaves DEC's website)

Agency for Toxic Substances and Disease Registry - Environmental Odors (leaves DEC's website)