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Brownfield Redevelopment in New York City and Community Air Monitoring – What you need to know

Written by Paul R. Pickering, Aeroqual Ltd.

Brownfield cleanup in New York City

As New York City’s need for space grows, existing stock of land must be used more effectively. Brownfield cleanup and redevelopment represents one of the best opportunities to engage communities and reclaim land for development in many cities. In 2018, the Mayor’s Office of Environmental Remediation (MOER) announced 1000×21, the most aggressive land cleanup and revitalization goal of any city in the world. This OneNYCinitiative seeks to remediate and redevelop 1,000 lots in NYC by the end of the de Blasio administration in 2021.


A vacant lot in Mott Haven, NY before remediation. Photo: OneNYC

Remediation air quality challenges

Any time a remediation or construction project involves earth-moving, it has the potential to release particulate (dust) and volatile organic compounds (VOCs) contaminants that exist below the surface. VOCs will readily transition to the gaseous, breathable phase, when exposed to air. Particulate emissions must be controlled to prevent impacts to the respiratory system. Negative impacts range from mild lung irritation to chronic lung disease. 

Regulations to protect community

To protect workers and the surrounding community, construction and demolition projects that involve excavation need to follow a stringent Community Air Monitoring Plan(CAMP), as specified by the New York State Department of Health (NYSDOH). If the excavation activities are occurring on a remediation or cleanup site, additional requirements are outlined in a guidance document known as DER-10. NYSDOH and DER-10 specifically apply to sites in New York. However, agencies and authorities in other states may also recognize these guidelines. They have been known to apply or refer to them for projects in their designated territories.

What is DER-10?

In 2010, the New York State Department of Environmental Conservation (NYSDEC) issued Division of Environmental Remediation (DER)-10 Technical Guidance for Site Investigation and Remediation, known as DER-10. This is the source document the NYSDEC refer to for authority to oversee remediation projects. It was designed to help parties and consultants (environmental and engineering) in developing and implementing investigation and remediation projects at contaminated sites.

DER-10 extensively (over 225 pages) describes the A to Z requirements for remedial site investigations, cleanups, post-cleanup monitoring and site closure. It presents detailed technical guidance for each of the investigative and remedial steps undertaken at contaminated sites. DER-10 covers procedures for assessing the environmental conditions at the site, including air monitoring during remediation activities.

What is CAMP?

Appendix 1A of the DER-10 outlines requirements for the implementation of a CAMP. This air monitoring plan is prescribed by NYSDOH. It involves direct-reading air monitoring instruments placed at defined locations around the perimeter of a remediation, construction or demolition site.

A CAMP requires real-time air monitoring for total VOCs (also referred to as total organic vapors) and PM10 (particulate matter 10 micrometers or less in diameter) at downwind and upwind locations relative to each designated work area when certain activities are in progress at contaminated sites. The CAMP is not intended for use in establishing action levels for worker respiratory protection. Rather, it is intended to protect the downwind community) from potential airborne contaminants released as a direct result of investigative and remedial work activities. The downwind community includes off-site receptors such as residences, businesses, and on-site workers not directly involved with the subject work activities. The specified CAMP action levels require increased monitoring, corrective actions to abate emissions, and/or work shutdown. Additionally, the CAMP helps to confirm that work activities did not spread contamination off-site through the air.

VOC and particulate monitoring

Basic requirements of a CAMP call for real-time air monitoring for VOCs and/or particulate levels at the perimeter of the exclusion zone, or work area. Sites known to be contaminated with heavy metals alone may only require particulate monitoring. If radiological contamination is a concern, additional monitoring requirements may be necessary in consultation with NYSDEC and NYSDOH. The table below summarizes CAMP Monitoring Action Levels for total VOC and particulate monitoring.

CAMP air monitoring equipment

Since the introduction of DER-10 in 2010, sensor-based technologies have reduced the cost of air monitoring and increased efficiency of the implementation of CAMP. Real-time air monitoring solutions are available to fit the budget and complexity requirements of every project. Below is a sampling of equipment options:

Entry Level – Basic environmental dust monitoring kit

Assembled kits, like this Basic Environmental Dust Monitoring Kit from Raeco Rents, are portable and suited to short-term or temporary CAMP. The ensemble includes an off-the-shelf dust monitor, handheld PID monitor for total VOCs, and a cloud-based telemetry system mounted in an environmental enclosure.

Ultimate Flexibility – All-in-one air quality monitor

All-in-one air quality monitors, like the AQS1 and the Dust Sentry from Aeroqual, are highly flexible and defensible, as well as good allrounders for short or long-term CAMP. In addition to the primary particulate fraction PM10, these monitors can also measure PM2.5, PM1 and Total PM. They can also be configured for monitoring total VOCs and NO2 emissions from remediation and construction sites. A robust light-scattering Nephelometer with sharp cut cyclone is integrated with a PID-based VOC analyzer module (or GSE-based NO2 gas module), Cloud telemetry platform, air quality software, and optional plug-and-play weather and noise sensors. Trigger alerts are programmable for SMS and email notifications, or can be used to activate an external VOC canister sample collection for speciated analysis according to EPA Method TO-15.

The Rolls Royce – GC-based perimeter air monitoring station

Perimeter air monitoring stations, like the AirLogics Classic 2, contain analytical, climatic, and communications instrumentation. This equipment includes: a gas chromatograph (GC) to measure specific VOCs, a respirable particulate meter to measure dust levels, shelter heaters and air conditioners, and a radio-based data acquisition system. These systems were originally developed for use in the cleanup of former manufactured gas plant (MGP) sites.

Weather monitoring

DER-10 guidelines require daily measurement of wind speed and direction, temperature, barometric pressure, and relative humidity, to establish background weather conditions. Wind direction data is used to position the air monitoring equipment in appropriate upwind and downwind locations.

The evaluation of weather conditions is also necessary for proper fugitive dust control. When extreme wind conditions make dust control ineffective, remedial actions may need to be suspended. There may be situations that require fugitive dust suppression and particulate monitoring requirements with more stringent action levels.

Additional monitoring

Under some circumstances, the contaminant concentration and/or toxicity may require additional monitoring to protect site personnel and the community. Additional integrated sampling and chemical analysis of the dust may be required. This must be evaluated when a Health and Safety Plan (HASP), is developed. Appropriate suppression and monitoring requirements are established for protection of people’s health and the environment.

Reporting

All recorded monitoring data is downloaded and field logged daily, including Action Limit Reports (if any) and daily CAMP monitoring location plans. Records are required to be maintained onsite for NYSDEC and NYSDOH to review. A description of the CAMP-related activities is also included in a monthly progress report submitted to the NYSDEC. The overall report submitted to the NYSDEC should include all CAMP monitoring records. If site works are stopped due to inability to control fugitive emissions to below the action limit, the NYSDEC is to be notified within twenty-four hours of the work stoppage.

For a real-life example of air monitoring at a remediation site please read my blog about the pilot cleanup of the Gowanus Canal, NY.

What CAMP solutions does Aeroqual offer?

Aeroqual’s Dust Sentry and AQS1 are flexible air monitoring platforms used by air quality professionals, and environmental and geotechnical consultants, for community air monitoring plans on remediation sites. We help environmental consultants deliver defensible data on projects by providing cost-effective and reliable instrumentation. For insights on the latest air monitoring trends at construction sites please read our blog about measuring NO2 and multiple PM fractions.


About the Author

Paul R. Pickering is the Business Development Director at Aeroqual Ltd., and is located in Auckland, New Zealand. Aeroqual Ltd. is a company that delivers innovative air quality and environmental monitoring solutions. He is passionate about making it easier to measure the air with advanced sensor-based technology. He believes that more relevant information about our environment can help us make better informed decisions, enjoy better quality of life, and make our planet a better home. 

Real-Time Global Radon Map

Airthings, a company specializing in digital radon detectors, recently launched RadonMap.com, a live global Radon map.  The map pulls constantly-updating Radon level data from Airthings’ devices all over North America, Europe ,and beyond to provide current localized analysis and advice – ideal for anyone looking to for the risks associated with radon exposure.

Facts about Radon

Radon is a radioactive gas that occurs naturally when the uranium in soil and rock breaks down. It is invisible, odourless and tasteless. When radon is released from the ground into the outdoor air, it is diluted and is not a concern. However, in enclosed spaces, like homes and offices, it can sometimes accumulate to high levels, which can be a risk to the health of the occupants of the building.

Radon gas breaks down or decays to form radioactive elements that can be inhaled into the lungs. In the lungs, decay continues, creating radioactive particles that release small bursts of energy. This energy is absorbed by nearby lung tissue, damaging the lung cells. When cells are damaged, they have the potential to result in cancer when they reproduce.

Exposure to high levels of radon in indoor air results in an increased risk of developing lung cancer. The risk of cancer depends on the level of radon and how long a person is exposed to those levels.

Exposure to radon and tobacco use together can significantly increase your risk of lung cancer. For example, if you are a lifelong smoker your risk of getting lung cancer is 1 in 10. If you add long term exposure to a high level of radon, your risk becomes 1 in 3. On the other hand, if you are a non-smoker, your lifetime lung cancer risk at the same high radon level is 1 in 20.

Radon Map

RadonMap.com aggregates radon level data from Airthings’ devices dispersed all over the world to provide accurate, local radon readings for users seeking current and reliable insight into the dangerous indoor gas and how much exposure they are subjected to daily.

Previously, gaining an understanding of localized Radon readings was only possible through professionally-administered tests or government data, offering a one-time snapshot rather than a constantly-evolving picture. With the introduction of the Airthings RadonMap.com, radon levels and fluctuations can be tracked accurately through a community of user-generated data. RadonMap.com instantly becomes a very reliable and up-to-date information source available for alerting the public about the presence of Radon in their environments and enabling them to take corrective action, if necessary, before a situation becomes critical.

About Airthings

Airthings is a Norwegian tech company that develops and manufactures both professional and consumer facing technology. These products include monitors for radon and other dangerous indoor air pollutants. The company was founded in 2008.

In Situ Treatment Performance Monitoring: Issues and Best Practices

The U.S. EPA recently released an issue paper (EPA 542-F-18-002) that describes how in situ treatment technologies may impact sampling and analysis results.  The paper discusses the best practices to identify and mitigate issues that may affect sampling and analysis.

The utility of monitoring wells for performance or attainment monitoring is based on the premise that contaminant concentrations measured in the wells are representative of aquifer conditions. However, during in situ treatment, various biogeochemical and hydrogeological processes and sampling and analysis procedures may affect the representativeness of the monitoring well and sample quality, which may not be adequately considered in current remediation practice.

A properly designed monitoring network that anticipates the distribution of amendments after injection would minimize impacts to monitoring wells.  However, predicting amendment distribution prior to injection is challenging such that impacts to monitoring wells are likely.

The purpose of The U.S. EPA issue paper is to:
• describe how in situ treatment technologies may impact sampling and analysis results used to monitor treatment performance; and
• provide best practices to identify and mitigate issues that may affect sampling or analysis.

The U.S. EPA issue  paper discusses eight potential sampling or analytical issues associated with groundwater monitoring at sites where in situ treatment technologies are applied. These issues are grouped under three topic areas:
• Issues related to monitoring wells (Section 2).
• Representativeness of monitoring wells (Section 3).
• Post-sampling artifacts (Section 4).

The paper presents issues that pertain to collecting water samples directly from a monitoring well and does not discuss the use of other sampling techniques, such as passive diffusion bags or direct push groundwater sampling.

US officials consider robots to prevent mine spills

As reported by the Associated Press, Crumbling mine tunnels awash with polluted waters perforate the Colorado mountains and scientists may one day send robots creeping through the pitch-black passages to study the mysterious currents that sometimes burst to the surface with devastating effects.

One such disaster happened at the inactive Gold King Mine in southwestern Colorado in 2015, when the United States Environmental Protection Agency (U.S. EPA) accidentally triggered the release of 3 million gallons of mustard-colored water laden with arsenic, lead and other toxins. The spill tainted rivers in three states.

a man in a hard hat sprinkling lime (white power) into a pool of muddy water next to a culvert. Here, lime is added to a settling pond to assist in the pH adjustment of the water (Credit: Eric Vance/U.S. EPA)

Now the U.S. EPA is considering using robots and other sophisticated technology to help prevent these types of “blowouts” or clean them up if they happen. But first, the agency has to find out what’s inside the mines, some of which date to Colorado’s gold rush in the 1860s.

Wastewater laden with toxic heavy metals has been spewing from hundreds of inactive mines nationwide for decades, the product of complicated and sometimes poorly understood subterranean flows.

Mining creates tainted water in steps: Blasting out tunnels and processing ore exposes long-buried, sulfur-bearing rocks to oxygen. The sulfur and oxygen mix with natural underground water flows to create sulfuric acid. The acidic water then leaches heavy metals out of the rocks.

To manage and treat the wastewater, the U.S. EPA needs a clear idea of what’s inside the mines, some of which penetrate thousands of feet into the mountains. But many old mines are poorly documented.

Investigating with robots would be cheaper, faster and safer than humans.

“You can send a robot into an area that doesn’t have good air quality. You can send a robot into an area that doesn’t have much space,” said Rebecca Thomas, project manager for the U.S. EPA’s newly created Gold King Superfund site, officially known as the Bonita Peak Mining District.

Instruments on the robots could map the mines and analyze pollutants in the water.

They would look more like golf carts than the personable robots from “Star Wars” movies. Hao Zhang, an assistant professor of computer science at the Colorado School of Mines, envisions a battery-powered robot about 5 feet long with wheels or tracks to get through collapsing, rubble-strewn tunnels.

Zhang and a team of students demonstrated a smaller robot in a mine west of Denver recently. It purred smoothly along flat tunnel floors but toppled over trying to negotiate a cluttered passage.

“The terrain is pretty rough,” Zhang said. “It’s hard for even humans to navigate in that environment.”

A commercial robot modified to explore abandoned mines — including those swamped with acidic wastewater — could cost about $90,000 and take three to four years to develop, Zhang said.

Robot in underground mine (Photo Credit: Tatlana Flower/AP File)

Significant obstacles remain, including finding a way to operate remotely while deep inside a mine, beyond the reach of radio signals. One option is dropping signal-relay devices along the way so the robot stays in touch with operators. Another is designing an autonomous robot that could find its own way.

Researchers are also developing sophisticated computerized maps showing mines in three dimensions. The maps illustrate where the shafts intersect with natural faults and provide clues about how water courses through the mountains.

“It really helps us understand where we have certainty and where we have a lot of uncertainty about what we think is happening in the subsurface,” said Ian Bowen, a U.S. EPA hydrologist. “So it’s a wonderful, wonderful tool.”

The U.S. EPA also plans to drill into mines from the surface and lower instruments into the bore holes, measuring the depth, pressure and direction of underground water currents.

Tracing the currents is a challenge because they flow through multiple mines and surface debris. Many tunnels and faults are connected, so blocking one might send water out another.

“You put your finger in the dike here, where’s the water going to come out?” Thomas said.

Once the U.S. EPA finishes investigating, it will look at technologies for cleansing the wastewater.

Options range from traditional lime neutralization — which causes the heavy metals dissolved in the water to form particles and drop out — to more unusual techniques that involve introducing microbes.

The choice has consequences for taxpayers.  If no company is found financially responsible, the EPA pays the bill for about 10 years and then turns it over to the state.  Colorado currently pays about $1 million a year to operate a treatment plant at one Superfund mine. By 2028, it will pay about $5.7 million annually to operate plants at three mines, not including anything at the Bonita Peak site.

The U.S. EPA views the Colorado project as a chance for the government and entrepreneurs to take risks and try technology that might be useful elsewhere.

But the agency — already dealing with a distrustful public and critical politicians after triggering the Gold King spill — said any technology deployed in Colorado will be tested first and the public will have a chance to comment before decisions are made.

“We’re certainly not going to be in the position of making things worse,” Thomas said. “So when I say we want to take risks, we do, but we want to take calculated, educated risks and not worsen water quality.”

Phytoforensics: Using Trees to Find Contamination

The United States Geological Survey (USGS) recently prepared on Fact Sheet on how phytoforensics can be used to screen for contamination prior to traditional sampling methods.  Phytoforensics is a low cost, rapid sampling method that collects tree-core samples from the tree trunk to map the extent of contamination below the ground.

By utilizing phytoforensics, environmental professionals can save the cost and time associated with traditional methods of subsurface investigation – drilling boreholes, installing monitoring wells.

Scientists at the Missouri Water Science Center were among the first to use phytoforensics for contamination screening prior to employing traditional sampling methods, to guide additional sampling, and to show the large cost savings associated with tree sampling compared to traditional methods, to guide additional sampling, and to show the large cost savings associated with tree sampling compared to traditional methods.

The advantages of phytoforensics include the following: quickly screen sites for subsurface contamination; cost- and time-effective approach that uses pre-existing trees; non-invasive method (no drill rigs or heavy equipment required); and representative of large subsurface volumes.

Phytoforensics testing involves the collection of a tree-core sample with necessary sampling equipment including an incremental borer, forceps, a sample vial, and gloves.  Samples are collected at about 3 feet (1 metre) above ground surface, placed into vials for subsequent laboratory analysis.

Similar to phytoforensics, phytoremediation is the field of looking to use plants to mitigate environmental pollutants and human exposures. As plants are efficient, key components in local and global water, carbon and energy cycles, they can influence pollutant transport and availability in many different ways.

Dr. Joel Burken, Missouri S&T professor of civil and environmental engineering, tests a tree in Rolla’s Schuman Park with then high school senior Amanda Holmes and S&T graduate student Matt Limmer. Photo by B.A. Rupert