The July 2021 issue of HETI Horizons provided an overview of anticipated changes in the 2021 update to American Society for Testing and Materials (ASTM) E1527, “Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process”. In this edition, some 18 months later, we present some of the major final revisions – which become effective this month.

In March 2022, the Environmental Protection Agency (EPA) issued a direct final rule (87 FR 14174) stating that it would continue to recognize the old ASTM Standard E1527-13 as well as the new Standard as satisfying the All Appropriate Inquiries (AAI) provision in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Then in May, EPA withdrew the direct final rule after receiving objections to continued use of ASTM E1527-13. Commenters argued that ASTM E1527-21 was developed with input from industry professionals, users, and regulators; and since it represents “good commercial and customary business practice” it should, therefore, replace ASTM E1527-13 altogether. Furthermore, commenters stated that using both the 2013 and 2021 Standards could generate confusion and add a level of complexity for users – as they would have to evaluate differences in costs/benefits of using one Standard over the other when reviewing multiple bids from environmental consultants.

In response to the concerns raised by commenters, EPA issued a new direct final rule (87 FR 76578) on December 15, 2022, stating that only the newer Standard should be used moving forward. However, to allow users to become accustomed to the new Standard, EPA is providing a sunset period of one year for ASTM E1527-13. The effective date of publication of EPA’s final rule is February 13, 2023 – meaning that the 2013 Standard will continue to satisfy AAI until February 13, 2024.

Definition Changes

The definition of a “Recognized Environmental Condition” (REC) was revised in an effort to clarify the term as it relates to the presence of hazardous substances or petroleum products at a property. A REC is now defined as (1) the presence of hazardous substances or petroleum products in, on, or at the subject property due to a release to the environment; (2) the likely presence of hazardous substances or petroleum products in, on, or at the subject property due to a release or likely release to the environment; or (3) the presence of hazardous substances or petroleum products in, on, or at the subject property under conditions that pose a material threat of a future release to the environment.

The new Standard now describes circumstances that elevate a “data gap” to the level of “significant data gap,” which is now defined as “a data gap that affects the ability of the environmental professional to identify a recognized environmental condition.” It also clarifies that a “data gap” – defined as “a lack of or inability to obtain information required by this practice despite good faith efforts by the environmental professional to gather such information” – is not inherently significant. Therefore, if a data gap does not affect the environmental professional’s ability to identify a REC, it does not constitute a “significant data gap.”

ESA Report Content & Viability Changes

ASTM E1527-21 now promotes the consistent use of “Subject Property” in a Phase I ESA report when referring to the property that is the subject of the environmental site assessment. Many environmental consultants use various terms like “subject property”, “site”, “target”, or “property” interchangeably in their reports; so, referring to the property undergoing the Phase I as “subject property” will reduce confusion among report readers and users.

The revised Standard requires the environmental professional to document in the report whether or not the features and conditions specified in the Site Reconnaissance section of the new Standard (§9.4.1 through 9.4.28) were observed. A blanket statement that “no RECs were observed at the Subject Property” will not meet the site description requirements in the revised Standard. This change in the ASTM Standard promotes good business practices as it shows the user or reader of the report that the environmental professional searched for all of the features and conditions specified in the Standard, and clearly describes their presence or absence in the ESA report.

The new Standard also clarifies the time frame for continued viability of an ESA report. The validity of a report, or the report’s expiration, depends on the earliest date at which certain components of the ESA were conducted. These include (1) interviews with owners, operators, and occupants; (2) searches for recorded environmental cleanup liens (a user responsibility); (3) reviews of federal, tribal, state, and local government records; (4) visual inspection of the Subject Property; and (5) declaration by the environmental professional. These components must be conducted within 180 days prior to the transaction date, and the dates at which they were conducted (except for environmental lien searches which are the user’s responsibility) must be identified in the report. This update to ASTM 1527-21 means that an ESA report is valid for 180 days from the date at which the first of these components was completed.

Although many environmental consultants have been including site plans in their ESA reports prior to the 2021 update, the new Standard now explicitly requires the inclusion of a site plan. The update further specifies that the following features must be included in the site plan: a north arrow; the approximate scale; all major structures; occupant/business names or land uses; and locations of features, activities, and conditions at the subject property and adjoining properties.

The old ASTM Standard stated that the environmental professional should exercise professional judgement in determining what historical sources should be reviewed to identify historical uses of the Subject Property. The new Standard specifically requires the review of four Standard Historical Sources – identified as aerial photographs, local street directories, topographic maps, and fire insurance maps – if reasonably ascertainable, likely to be useful, and applicable to adjacent properties. The environmental professional should exercise professional judgement and review additional historical sources to identify past uses that may indicate a REC in connection with the subject property.

ASTM E1527-21 clarifies that environmental lien and activity and use limitation (AUL) searches are to be completed by users and searches for land title records must be completed from the present back to 1980.

The new Standard addresses the growing concern regarding “emerging contaminants” such as per- and polyfluoroalkyl substances (PFAS), by indicating that once these emerging contaminants are classified by EPA as hazardous substances under CERCLA, they will be evaluated within the scope of ASTM E1527. This suggests that users may want to consider the risks of emerging contaminants at the subject property, and request that the environmental professional address the potential for emerging contaminants in the ESA report as a non-scope issue.

What It All Means

Overall, the aim of the new Standard is to strengthen the framework for environmental due diligence by clarifying the scope and the depth of review for an ESA and revising certain terms and definitions to make them more concise and eliminate potential confusion.

For a property owner, lender, consultant, or other interested party, it is important to be aware of these changes and to understand the new requirements set forth in ASTM E1527-21. Effective implementation of this ASTM Standard plays a critical role in managing                 environmental liability and financial risk. Ultimately, adherence to E1527-21 will assist a   property owner with qualifying for landowner liability protections (LLPs) against contamination and remediation requirements under CERCLA; and promote increased uniformity and transparency of Environmental Site Assessment reports prepared by environmental professionals.

HETI staff are well-versed in the ASTM Standard for environmental assessment of commercial real estate and are ready to support our clients as questions arise regarding the usage and interpretation of the new ASTM 1527-21.

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This is the first of a two-part update summary of technologies used for treating “infectious” waste generated at healthcare facilities, research and clinical laboratories, biotechnology/pharmaceutical laboratories, and the like. Part 1 reviews what are considered currently viable technologies. Part 2 will provide recommendations for evaluating, selecting and implementing the best, most cost-effective system for a facility-specific application.

Starting Point – Properly Describe and Define the Waste

Evaluation, decision-making and the implementation of any facility-specific waste management, treatment and disposal program should always begin with the establishment of a clear, precise description and characterization of the waste stream, along with a compositional breakdown of its main constituents. Failure to do so could result in any number of problems – ranging from management difficulties to the procurement of an inadequate, noncompliant, or overly costly waste treatment system.

It is also important that proper, clear terminology be used to describe or define the waste as opposed to vague, generic terms – such as “medical waste” – which provide no useful information about the waste itself. There are at least a dozen terms often used when referring to “medical waste” – including “infectious waste”, “contaminated waste”, and “clinical waste”. But such terms have different meanings and are subject to varying interpretations.

Use of the term “infectious waste” is a prime example where clarification is recommended; simply because only a small fraction of medical waste is actually infectious. Technically, infectious waste comprises disposed items that have been contaminated by a pathogenic microorganism or pathogens (such as bacteria, viruses, or fungi) capable of causing an infectious disease in healthy humans. The primary source for such contamination is contact with blood or body fluids from medical procedures. However, since it’s problematic to know with certainty whether any such contacted fluids actually contain viable pathogens, it is standard practice for such contaminated waste to be designated as being “infectious” and collected in red-colored containers having a universal biohazard symbol. All such color-coded containers are assumed to be filled with “infectious” waste, but published data have shown that upwards of 95% of the waste is not “infectious” and poses a negligible risk of transmitting an infectious disease.

Viable Medical Waste Treatment Technologies

Terminology

Waste Processing vs. Waste Treatment

The terms “waste processing” and “waste treatment” are often used interchangeably; but they are different. Waste processing involves the application of equipment, such as shredders and compactors, to change the physical characteristics of a waste for a particular purpose; while waste treatment involves the application of processes and equipment to convert wastes having hazardous characteristics or properties to a residue that is safe for handling and disposal.

Disinfection vs. Sterilization

The terms “disinfection” and “sterilization” are also often used interchangeably, but they also have different meanings. Disinfection involves processes for eliminating harmful microorganisms from objects and surfaces to an acceptable level, while sterilization involves processes for killing all microorganisms. Only a few medical waste treatment technologies, such as high-temperature incineration, are capable of providing sterilization. But other technologies provide a sufficiently high level of disinfection (typically 99.99% or higher) to be considered acceptable in accordance with most state         regulations.

Evolutionary Development

Until the early 1990s, incineration and steam autoclaving were widely considered the only proven, viable medical waste treatment technologies. But a series of national events, including fears associated with the AIDS epidemic, triggered the rapid proliferation of non-incineration treatment technologies – with more than 200 different technologies developed by the early 2000s. Within a few years virtually all of them proved unsuccessful and became no longer available. Today, the only proven, viable, medical waste treatment technologies are again incineration, steam autoclaving, and possibly pyrolysis. A few other technologies – including ozonation and        microwaving – continue to be promoted; but none of them have demonstrated proven success and basically reflect failed technologies from decades ago.

Incinerator Systems & Equipment

Incineration is a high-temperature combustion process suitable for destroying virtually all types of waste. A properly designed, controlled, and operated incinerator system readily converts medical waste (and almost all other types of waste generated at healthcare facilities) to an inert, sterile, non-hazardous, unrecognizable ash residue that is safe for disposal in a sanitary landfill. Incinerator systems typically reduce the weight and volume of medical waste by upwards of 95 percent or more, and provide the opportunity to recover useful energy from the waste in the form of steam via heat recovery boilers.

The most widely used incinerator technology for disposing of medical waste is termed controlled air type incineration – because of the way air for combustion is introduced and controlled. However, regardless of incinerator type, the key to procuring a successful, reliable, compliant system involves the application or specification of widely recognized design, construction and operational criteria for the incinerator itself and all associated components (such as the waste loading system, ash removal system, burners and blowers, stack and breechings, controls and instrumentation, and air pollution control devices).

Steam Autoclave Systems & Equipment

Steam autoclaving uses pressurized, saturated steam injection within a chamber for inactivating or killing pathogenic microorganisms. It is suitable for treating or disinfecting most types of medical waste; but they are not considered acceptable for treating pathological waste, waste containing bulk quantities of fluids, or hazardous waste and chemicals. Autoclaving effectiveness or efficiency is a function of steam temperatures, the ability of the steam to contact                  microorganisms within loaded waste containers, and the duration of steam contact with contaminated items. Since most autoclaved waste remains recognizable and because sharps within the waste containers remain as potential puncture hazards, it is often necessary to shred the autoclaved waste to render it unrecognizable and safe for  handling and off-site disposal. 

Pyrolysis Treatment Technologies

Pyrolysis technologies use indirect heating sources – without the introduction of air or oxygen – to heat the waste to high temperatures. This process drives off volatile gases from the waste, but such gases need to be combusted in a fuel-fired afterburner prior to stack discharge. The solid residues after pyrolysis have high percentages of carbonaceous, recognizable items that require additional special processing such as shredding or encapsulation prior to disposal.

HETI Services

HETI has extensive expertise, experience, and full-service capabilities involving all aspects of medical waste management, treatment and disposal – including feasibility evaluations, engineering and design, permitting, construction administration, and ongoing compliance support. HETI staff have provided such services to more than 500 healthcare, university and biomedical research facilities throughout the United States and internationally.

U.S.-derived fossil fuels are known as the “cleanest” in the world! If everybody drove an electric car, we could achieve zero emissions! Can both statements be true or are we cherry-picking the facts?

For fossil fuels, the waste stream from drilling operations is known as “exploration and production” (or E&P) waste. E&P wastes are derived from spent drilling mud, rock fragments (“cuttings”), and fluids generated from underground materials that come to the surface during drilling operations. These wastes may sometimes contain environmentally unfriendly contaminants and trace metals. Appropriate management of the wastes in environmentally sensitive areas, such as the North Slope of Alaska, requires newer techniques and technologies. These new measures have changed the way the oil and gas industry manages E&P wastes to reduce long-term risks to the environment.

The North Slope of Alaska holds vast proven reserves of oil and gas in five large oil fields, including Prudhoe Bay – the largest oil field in North America, encompassing 5,000 acres. E&P operations on the North Slope commenced in the 1950s. Operators historically managed wastes by constructing rectangular gravel berm-enclosed pits on top of the frozen tundra and adjacent to each well site to discard cuttings, mud, solids, and drilling fluids.

Environmental Liability

By 1980, hundreds of reserve pits, several acres in size, dotted the Alaska landscape – making them not only eyesores, but also a risk of melting the underlying permafrost and causing releases to the surrounding soils, groundwater, and surface waters. Permafrost, or ground that is permanently frozen, is a vital component to the North Slope ecosystem. Raising the temperature of permafrost through operation of E&P waste pits can mobilize contaminants and cause erosion, as well as release bound-up carbon and organic materials through greenhouse gases.

A study conducted by the U.S. Environmental Protection Agency (EPA) of reserve pits and nearby pond areas revealed an increase in concentrations of petroleum hydrocarbons, salts, and other contaminants from samples collected in ponds downgradient of reserve pits. Concentrations of petroleum hydrocarbons, barium, chloride, potassium, chromium, copper, iron, nickel, lead, and selenium have been reported. Moreover, wildlife studies conducted by the Arctic National Wildlife Refuge determined that macro-invertebrates in tundra ponds, an important food source for birds, were becoming depleted.

Several petroleum companies operating on the North Slope began putting their general liability insurers on notice, as more data from studies pointed to potential pollution damages to the environment coming from the reserve pits. At about the same time, the Alaska Department of Environmental Conservation (ADEC) began exploring options and new regulations. Insurance carriers argued that the insured needed to demonstrate that a release of contamination occurred from the reserve pits and that a directive for cleanup was required by the ADEC. Otherwise, the carriers’ position indicated that the removal of the wastes in the reserve pits would be considered a deferred cost-of-doing-business expense that should be borne by the insured directly as part of their ongoing operation and maintenance costs.

Closure Solutions

By the mid-1990s, it became increasingly clear that the ADEC would require a new method of disposal of drilling wastes and that traditional reserve pits posed many potential long-term environmental liabilities.

ADEC instituted a new closure standard – Alaska Administrative Code 18, Chapter 60, Section 440 (18 AAC 60) – that required reserve pits to be capped. The closure process involved excavation of the reserve pits below the drilling waste/tundra interface, collection of closure and surface water samples, and return of the reserve pit landscape to original pre-drill conditions.

A settlement agreement was reached between ARCO and the National Resources Defense Council (NRDC) which directed ARCO to use an alternative disposal method, known as the “grind-and-inject” (G&I) method to dispose of fluids underground at a new G&I plant facility.

Alternative Cleanup Solutions

G&I alternative disposal methods were derived from down-hole disposal methods used in the 1940s that were first used to inject water produced from oil and gas drilling into depleted wells. However, the down-hole method did not involve injecting solids. ARCO then borrowed several mining techniques to grind and pulverize suspended rock materials in the mud recirculation system to successfully demonstrate this method would work. The mud passed through shaker screens, desanders, and centrifuges at the surface to remove finer particles, so the slurry could be pumped into the formation without plugging the fine pores and permeable channels in the rock formation.

As the G&I method became the industry standard on the North Slope, it soon became practicable to excavate and haul the wastes from the reserve pits for disposal at the G&I plant, where it was made into slurry and injected into the subsurface via several injection wells.

Conclusion

To date, more than 2.5 million cubic yards of reserve pit material and over six hundred reserve pits have been closed in Alaska. The G&I process has helped eliminate reserve pits that once dotted the North Slope landscape – improving aesthetics, as well as removing potential sources of long-tail environmental liability. In addition, the permafrost, surface water quality, and wildlife habitats have been restored.

HETI…Here to Help

HETI staff continue to monitor E&P activities at drilling and petroleum operations in various states and stay informed of new regulations in the oil industry when dealing with E&P wastes. HETI’s extensive engineering and environmental experience enable us to assist our clients in understanding the risks and changing regulatory environment of E&P activities and technology.

References:

“Drilling fluids and the Arctic Tundra of Alaska: Assessing contamination of wetlands habitat and the toxicity to aquatic   invertebrates and fish”; Woodward, D., E Snyder-Conn, R. Riley, and T. Garland; US Environmental Protection Agency EPA/600/J-88/246

“Oil Drilling in Alaska”; FEE Foundation for Economic Education; September 1, 1993; Sarah Anderson

18 Alaska Admin. Code 60.440 – Closure of inactive reserve pits; October 26, 2021

“30 Strong: The drilling waste dilemma”; Petroleum News; Volume 12, No. 41

“Site-Wide Project Work Plan-Part I; Part 2: Current Conditions Report Prudhoe Bay Facility, Alaska”; Oasis Environmental; January 28, 2008

“Effects of Prudhoe Bay Reserve Pit Fluids on Water Quality and Macroinvertebrates of Arctic Tundra Ponds in Alaska”; Yukon Flats National Wildlife Refuge and Fairbanks Fish and Wildlife Enhancement Office; September 1987

“Oil Development Damages Air, Water, and Wildlife”; the Arctic National Wildlife Refuge

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In construction safety, basic measures most companies take in evaluating and controlling construction hazards are through written safety & health plans. These plans, typically designed to address site-specific construction hazards, then become an integral part of a company’s safety & health program. Implementing a written plan to address identified hazards in the workplace is a crucial step to bring awareness to employees, reference applicable Occupational Safety & Health Administration (OSHA) construction regulations, prevent accidents, and drive a company culture that prioritizes safety.

Key Safety & Health Programs

Important safety & health programs, designed to address and control safety hazards facing construction workers, include:

♦  Accident Investigation ♦  Hot Work

♦  Bloodborne Pathogens ♦  Housekeeping

♦  Compressed Gas Safety ♦  Job Safety Analysis

♦  Confined Spaces ♦ Jobsite Safety Field Manuals

♦  Cranes & Derricks in Construction ♦  Lockout/Tagout

♦  Electrical Safety ♦  Overhead Cranes

♦  Emergency Action Plan & Fire Safety ♦ PPE

♦  Ergonomics ♦  Powered Industrial Trucks & Forklift Safety

♦  Fall Protection ♦   Respiratory Protection

♦ Silica/Lead/Hexavalent Chromium/Asbestos Awareness

♦  First Aid, Hazard Communication

♦ Hearing Conservation    

♦  Heavy Equipment Safety ♦  Trenching & Excavation

OSHA Construction Standard: Employer Responsibilities

An OSHA Construction Safety Standard is a legal requirement that employers must follow to minimize employee risk of injury or illness in the performance of work. Adherence to OSHA standards protects workers from fatal hazards and health risks. The Construction Standard, found in 29 CFR 1926, addresses some of the more prominent employer responsibilities regarding safety and health of employees in the construction industry – including:

• Ensure employees are adequately trained/experienced to operate equipment/machinery.
• Ensure first aid services/medical provisions are available.
• Provide and require wearing of appropriate personal protective equipment (PPE) in operations where hazardous conditions are present.
• Ensure harmful debris – such as scrap lumber, protruding nails, etc. – is cleared from work areas and walkways during construction.
• Ensure adequate illumination in walking-working areas where work is in progress.
• Ensure access to PPE for excessive noise exposure, where necessary.
• Provide fall protection – such as guardrails, safety nets, safety harnesses – to employees working at heights of six feet or more.
• Develop and consistently implement effective fire protection/ prevention program throughout construction/demolition projects.
• Ensure all electrical equipment used at job sites is safe/free from recognized hazards.
• Ensure that pressure vessels/boilers have current, valid certification from insurance company or regulatory authority.

Aids to Compliance

To enhance their efforts to comply with the OSHA construction standard, employers can implement a variety of aids to that promote compliance and influence employee behavior. Some of the more popular approaches are:

Develop an Effective Safety & Health Policy — Senior management should create a safety & health policy with clear objectives – indicating the basic health and safety philosophy of the organization. This policy should include the site-specific, written safety & health programs mentioned above.

Enable Frontline Workers to Respond Proactively – OSHA standards can be easily met when organizations empower frontline workers to mitigate health and safety risks at the onset. Before commencing work, site supervisors should regularly conduct an OSHA Toolbox meeting for workers to be aware or reminded of job    hazards, best practices, and preventive measures. Environmental Health & Safety (EHS) managers should implement real-time Incident Reporting through mobile-ready OSHA 300 forms to identify leading indicators to safe performance. Establishing an adaptive work environment allows employees to take greater ownership of occupational health and safety for themselves and their co-workers.

Maximize Use of Cost-Effective Digital Tools – Time can be saved by replacing paper-based incident reporting/recordkeeping with powerful software tools. Proper recordkeeping and documentation of safety & health programs are critical in substantiating compliance with OSHA standards.

Celebrate Wins to Boost Motivation – EHS managers should recognize safe and on-time performance – facilitating peer-to-peer observations, providing informal feedback, and engaging in follow-up discussions – to further encourage and support safe behavior among employees. Consistent hazard prevention, prompt incident reporting, proactive  response to safety issues, and appropriate solutions to recurrent problems should also be rewarded.

Stay Updated by Consulting the OSHA Webpage Regularly — Maintaining compliance with OSHA standards entails the commitment of the organization, its management, and all employees to prioritize health and safety. OSHA’s FAQs (at www.osha.gov) provide up-to-date releases/revisions of OSHA standards – such as the final rule to improve tracking workplace injuries and illnesses, new training requirements, and compliance audit schedules.

Safety Training — Employers are responsible for providing workers with the knowledge and skills required to perform all work-related tasks while ensuring their safety. While educating and training all workers to follow OSHA’s standards, employers must provide safety training in a language and vocabulary workers can understand.

HETI…Helping Evaluate and Control Construction Hazards

HETI can assist facilities facing the challenges discussed in this newsletter through an assessment of health and safety hazards and compliance with the OSHA Construction Standard. Our experienced industrial hygienists and safety professionals can provide a workplace evaluation for construction-related hazards – recommending appropriate and feasible solutions to control them. If hazard control methods are already in place, HETI can conduct an assessment to document their effectiveness.

References:

• Occupational Safety and Health Administration, Department of Labor, 29 CFR 1926 OSHA Construction Standard: www.osha.gov/laws-regs/regulations/standardnumber/1926
• Occupational Safety and Health Administration Website, Standards, Enforcement, Topics, Help and Resources: https://www.osha.gov/

Firestopping devices are forms of passive fire protection used to seal the openings or passages in fireproof floors, walls, or ceilings and to impede the spread of flames, smoke and toxic gases. A firestop device fills the holes created during the installation of communication or electricity cables, plumbing, or ventilation ducts. It contains a soft fire-retardant material (usually red) that closes the gaps between pipes, cables, ducts, holes, edges, etc.– thus blocking fire and smoke from spreading and enhancing safety for building occupants. Firestopping is currently required for top of walls, curtain walls, slab edges, joints, and pipe penetrations. Note that firestopping should not confused with fireproofing which is the spray-on product applied to building materials.

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In older homes and buildings, lead can leach from service lines, solder, and fixtures into tap water and become a significant source of lead exposure. In children, lead exposure can cause irreversible and life-long health effects – including decreasing IQ, focus, and academic achievement. ¹ Continue Reading →

New spill reporting regulations from the Connecticut Department of Energy and Environmental Protection (DEEP) are now in effect. The regulations (RCSA §§ 22a-450) require reporting to DEEP for a broad spectrum of spills – including many which would likely be considered minor or of little concern by the regulated community. Continue Reading →

It’s been more than eight years since we reported on the health & safety and risk management issues related to spray polyurethane foams. So, we decided to re-visit the HETI Horizons we published in November 2013 – updating, as appropriate, based on we what we know today.

One of the cutting-edge advances in new construction was the use of spray polyurethane foam insulation for energy conservation. Although the chemistry has been around since the 1940s, the past twenty years have seen the application expand in commercial buildings and high-end homes. The use of spray foam is likely to reach $2.1 billion by 2025, with an annual growth rate of 5%.

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In April 2022, the United States Environmental Protection Agency (EPA) announced its final plan for regulation of perchlorate in drinking water. The plan formalizes the agency’s withdrawal of its 2011 decision to promulgate a Maximum Contaminant Level (MCL) for perchlorate, and announces actions that will be taken to minimize perchlorate impacts in the future. Continue Reading →

Crystalline silica is a common mineral found in the earth’s crust. Materials like sand, stone, concrete, and mortar contain crystalline silica. It is also used to make products such as glass, pottery, ceramics, bricks, and artificial stone. Respirable crystalline silica – very small particles at least 100 times smaller than ordinary sand found on beaches and playgrounds – is created when cutting, sawing, grinding, drilling, and crushing stone, rock, concrete, brick, block, and mortar.

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