Foundry Sand Reuse in Georgia

Planning to reuse spent foundry sand in Georgia? This guide covers the rules that apply, the tests that decide how the sand can be managed, and what Georgia’s rules require before the sand can be reused.

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. Georgia’s solid waste rules use the term “recovered materials.” Material that meets the rule’s conditions is excluded from regulation as solid waste. EPD’s Recovered Materials Unit reviews applications for beneficial reuse projects.

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.

Georgia’s recovered materials rule

Georgia’s reuse rule is Ga. Comp. R. & Regs. 391-3-4-.04(7). It has no provision written for foundry sand. Recovered materials, and facilities that process them, are excluded from regulation as solid waste. To qualify, the material must:

1. have a known use, reuse, or recycling potential;
2. be feasibly used, reused, or recycled; and
3. have been diverted or removed from the solid waste stream for sale, use, reuse, or recycling.

The rule counts a material as used, reused, or recycled when it is:

1. an ingredient, including an intermediate, in a process to make a product;
2. employed for its original purpose or a different one, without physically changing its composition; or
3. an effective substitute for a commercial product, when the substitution does not threaten human health or the environment and the facility is not a solid waste thermal treatment facility.

Placing material on or in the land is not reuse when it amounts to disposal that, in the Director’s opinion, may threaten human health and the environment. The rule’s examples include using inherently waste-like materials as fill.

Stockpiles have a limit. During any rolling 12-month period, at least 75% of the stored material, by weight or volume, must be recycled, sold, used, or reused. Material accumulated speculatively is solid waste.

Material that does not qualify is solid waste. Under Rule 391-3-4-.02(1), handling it requires a solid waste handling permit unless an exemption or permit-by-rule applies.

Working with EPD

• Who reviews: the Recovered Materials Unit in EPD’s Land Protection Branch reviews applications for beneficial reuse projects. It also gives technical assistance on industrial by-products.
• Proof of reuse: show sale, use, or reuse with bills of sale or other records of the material’s movement to a recycler or user. You must also show a known market or disposition for the material.
• Processing: anyone claiming to run a recovered materials processing facility must show it has the necessary equipment.
• Solid waste permits: if the sand is handled as solid waste, disposal and processing permit applications go through GEOS, EPD’s online system.
• Other rules: meeting the solid waste rules does not relieve you of other local, state, or federal requirements.

EPD Recovered Materials Unit technical duty officer: (404) 362-2537. Solid waste technical assistance duty officer: (404) 362-2692.

Hazardous waste determination

Georgia adopts the federal hazardous waste rules (40 CFR Parts 124, 260–266, 268, 270, 273, and 279, as amended through October 1, 2021) by reference in Ga. Comp. R. & Regs. 391-3-11-.01.

Georgia adds a record step for stored hazardous waste. Under Rule 391-3-11-.08(3), weekly inspections of central accumulation areas must be documented and kept on site for three years.

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, EPD, 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.

Under Rule 391-3-4-.04(7)(f)4, using soil as fill is disposal when its Appendix VIII hazardous constituents exceed background levels in the area filled.

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.

EPD reviews beneficial reuse projects case by case. Check any destination and proposed use with EPD before scheduling delivery.

When you talk to EPD, describe the proposal using the categories in Rule 391-3-4-.04(7)(f). For example, is the sand a concrete ingredient, or a substitute for purchased fill sand? 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.

Storage and records

Store spent sand on a defined pad or in bins, control dust and runoff, and keep other foundry wastes out. Plan volumes so at least 75% of stored sand is used, sold, or recycled in any rolling 12-month period. Material accumulated speculatively is solid waste under Rule 391-3-4-.04(7)(b)–(c).

Keep the waste determination, lab reports, EPD correspondence, and the receiving site’s acceptance together. Keep bills of sale or shipping records that show tonnage, dates, and destinations. 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 with EPD’s Recovered Materials Unit that the use meets Georgia’s recovered materials conditions.
5. Get written acceptance and arrange pickup.

Common questions

Rules and guidance

• Georgia EPD: Recovered Materials
• Georgia EPD: Land Protection Branch programs and contacts
• Ga. Comp. R. & Regs. 391-3-4: Solid Waste Management
• Georgia EPD: Solid Waste and Recovered Materials Forms (GEOS)
• Ga. Comp. R. & Regs. 391-3-11: Hazardous Waste Management
• 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