Foundry Sand Reuse in Kentucky

Planning to reuse spent foundry sand in Kentucky? This guide covers the rules that apply, the tests that decide how the sand can be managed, and how Kentucky’s beneficial reuse permit-by-rule works.

Key terms

Spent foundry sand

Foundries bond silica sand into molds and cores for casting metal. The sand is reused many times in the plant. Spent foundry sand is molding and core sand that can no longer make molds or cores.

Green sand and chemically bonded sand

Green sand is bonded with clay, usually bentonite, plus water and additives such as carbon. Chemically bonded sand uses resin binders. Most cores are chemically bonded. The binder system affects what the spent sand contains.

Beneficial reuse

Beneficial reuse puts a waste material to productive use instead of disposing of it. In Kentucky, “beneficial reuse of solid waste” is a permit-by-rule under 401 KAR 47:150. A reuse that meets the rule’s conditions needs no written permit.

TCLP

The Toxicity Characteristic Leaching Procedure (EPA Method 1311) measures how much of certain contaminants can leach from a sample. It is one part of deciding whether a waste is hazardous.

What’s in your spent sand?

Spent sand carries what the casting process added: binder residue, metal fines, and burnt core material. The alloy matters most. Sand from iron, steel, and aluminum foundries is the most commonly reused. Sand from leaded brass and bronze foundries is often regulated as hazardous waste.

Keep each stream separate. Baghouse dust, shotblast fines, cupola slag, broken cores, and core room sweepings need their own evaluation. Mixing them into spent sand can change how the whole load is managed. Track the alloys cast, the binder system, and any process changes.

Kentucky’s beneficial reuse rule

Kentucky’s beneficial reuse rule is 401 KAR 47:150, Section 1(11). It lists “beneficial reuse of solid waste” as a permit-by-rule. A qualifying reuse needs no permit application or written authorization. It qualifies only when it:

1. does not violate the environmental performance standards in 401 KAR 47:030; and
2. does not present a threat of imminent hazard to human health or substantial environmental impact.

The performance standards in 401 KAR 47:030 cover flood plains, endangered species, surface water, groundwater, food chain crops, PCBs, disease, air, safety, public nuisance, and wetlands.

Fill needs a purpose. When inert solid waste is used as structural fill, the property owner must have an intended use for the filled area. That use separates beneficial reuse from open dumping, which KRS 224.40-100 prohibits.

The generator keeps some responsibility. It does not have to be the permittee. But it may be held liable for remedial measures if the reused waste causes a release of a reportable quantity of a pollutant (KRS 224.1-400).

Asking DWM for written approval

• When: written approval is optional. If you want it, file DEP 7098, “Application for a Permit-by-Rule for Beneficial Reuse of Solid Waste,” with the Division of Waste Management (DWM).
• Who files: the waste generator, the end user, or a third-party manager or broker.
• What to include: the waste type and volumes (acres affected, monthly volume, and lifetime tons); the proposed reuse, its personnel and equipment, and its benefit; how the reuse meets the environmental performance standards; a site plan; and a USGS 7.5-minute topographic map of the location.
• Property owner: if the owner is not the applicant, the owner signs a notarized acknowledgement of liability (Addendum 1).
• Signature: a person with signature authority under 401 KAR 47:160 signs the certification before a notary. Consultants may not sign it.
• How to submit: the form asks for the original and one copy, sent to DWM.
• Fee and review time: 401 KAR 47:090 sets a $750 fee for a beneficial reuse determination. Its technical review time is 90 calendar days.
• Help: staff at DWM’s regional offices may help decide whether a proposed reuse is likely to meet the rules.

DWM Solid Waste Branch: (502) 564-6716.

Hazardous waste determination

Kentucky adopts the federal hazardous waste rules by reference in 401 KAR Chapter 39, with state changes. 401 KAR 39:060 adopts 40 CFR Parts 260, 261, and 268, among others. 401 KAR 39:080 adopts the generator rules in Part 262.

Kentucky adds generator steps. Small and large quantity generators must register with the Cabinet. They renew each year, at least 45 days before the certificate of registration expires. Generators other than very small quantity generators file a Hazardous Waste Annual Report.

Under 40 CFR 262.11, the foundry must decide whether its spent sand is hazardous:

1. Make the determination at the point of generation, before mixing or dilution. Repeat it if the waste may have changed.
2. Check whether the waste is excluded from the hazardous waste rules.
3. Check whether it matches a listed hazardous waste.
4. Check for hazardous characteristics, including toxicity. Use knowledge of the materials and process, testing, or both. Test when knowledge alone is not enough.

Small and large quantity generators must keep records supporting the determination for at least three years after the waste was last sent for treatment, storage, or disposal.

TCLP testing and limits

Tell the lab the alloys cast, the binder system, and which streams the sample includes. Use representative samples. Agree on the sampling plan with the lab, DWM, and the receiving site before collecting.

A waste is hazardous for toxicity if its TCLP extract meets or exceeds any limit in 40 CFR 261.24. The limits for the RCRA metals are:

Passing TCLP addresses toxicity for the substances tested. It does not approve reuse or rule out other reasons a waste may be hazardous. See material testing for sampling basics.

Kentucky adds a PCB limit for land placement. Solid waste with PCBs at 1 mg/kg (dry weight) or more cannot be placed on the land, except at certain landfills (401 KAR 47:030, Section 8). The reuse also may not contaminate an underground drinking water source above the maximum contaminant levels in Section 6.

Finding a reuse destination

EPA’s 2014 risk assessment found three uses protective of health and the environment for silica-based spent sand from iron, steel, and aluminum foundries: manufactured soil, soil-less potting media, and road subbase. EPA and USDA support those uses. The finding does not cover sand from brass or bronze foundries, olivine sand, or sand mixed with other foundry wastes such as baghouse dust or cupola slag. EPA defers to state programs, so the state rules on this page still decide each use.

DWM decides reuse case by case. Check any destination and proposed use with DWM before scheduling delivery.

Describe the job the sand will do at the receiving site. DWM’s examples of permit-by-rule reuse include industrial byproducts used as substitute ingredients in manufacturing. For fill, confirm the property owner’s intended use for the area. Get the receiving site’s specifications and written acceptance. If reuse is not cleared, arrange disposal that fits the waste determination.

Worker protection

• Silica: foundry sand is mostly crystalline silica. OSHA’s general industry standard, 29 CFR 1910.1053, sets a permissible exposure limit of 50 µg/m³ of respirable crystalline silica as an 8-hour average. Exposure assessment starts at the 25 µg/m³ action level.
• Construction use: crews placing sand as fill or subbase fall under the construction silica standard, 29 CFR 1926.1153.
• Lead: brass and bronze foundries that cast leaded alloys also follow OSHA’s lead standard, 29 CFR 1910.1025.
• Dust: control dust during shakeout, storage, and loading.

Kentucky Occupational Safety and Health (Kentucky OSH) runs Kentucky’s OSHA-approved State Plan. For most employers, its standards apply in place of federal OSHA and must be at least as effective.

Storage and records

Store spent sand on a defined pad or in bins, control dust and runoff, and keep other foundry wastes out. Kentucky’s performance standards bar discharges of pollutants to waters of the Commonwealth and nuisances from blowing debris (401 KAR 47:030).

Keep the waste determination, lab reports, any DWM approval, and the receiving site’s acceptance together. Record tonnage shipped, dates, and destinations. DEP 7098 includes a log sheet for the generator, recipient, delivery date, and amount reused. DWM recommends keeping it for the most recent three years of operation. Keep determination records for at least three years.

Before pickup

1. Identify the alloys cast, sand and binder systems, separate streams, monthly volume, and plant location.
2. Make the hazardous waste determination and complete the required tests.
3. Choose a destination and get its material specifications.
4. Confirm the reuse meets 401 KAR 47:150 and 47:030. File DEP 7098 if you want written approval.
5. Get written acceptance and arrange pickup.

Common questions

Rules and guidance

• Kentucky DWM: Beneficial Reuse
• Kentucky DWM: Solid Waste Branch Forms (DEP 7098)
• 401 KAR 47:150: Special types of permits
• 401 KAR 47:030: Environmental performance standards
• 401 KAR 47:090: Solid waste permit fees
• 401 KAR 39:060: Hazardous waste general requirements
• 401 KAR 39:080: Hazardous waste handlers
• 40 CFR 262.11: Hazardous waste determination
• 40 CFR 261.24: Toxicity characteristic
• EPA Method 1311: TCLP
• EPA: Beneficial Uses of Spent Foundry Sands
• EPA: Risk Assessment of Spent Foundry Sands in Soil-Related Applications
• 29 CFR 1910.1053: Respirable crystalline silica
• 29 CFR 1926.1153: Respirable crystalline silica in construction
• Kentucky Occupational Safety and Health (Kentucky OSH)