Foundry Sand Reuse in South Dakota | Foundry Recycling Services

Planning to reuse spent foundry sand in South Dakota? This guide covers the rules that apply, the tests that decide how the sand can be managed, and what DANR needs 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. South Dakota law ranks recycling and reuse above landfill disposal. Its solid waste rules apply through DANR permits.

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.

South Dakota’s solid waste permit rules

South Dakota’s solid waste law is SDCL chapter 34A-6. SDCL 34A-6-1.2 sets the state’s order of preference. Volume reduction at the source comes first, then recycling and reuse, then energy production, then disposal.

Solid waste includes discarded material from industrial operations (SDCL 34A-6-1.3). The rules define industrial waste as solid waste generated by manufacturing or industrial processes.

The rules are ARSD article 74:27. Under ARSD 74:27:08:01, no one may build or operate a solid waste facility without a valid permit. A solid waste facility is one used for the storage or disposal of solid waste (SDCL 34A-6-1.3).

General permits cover groups of similar facilities. ARSD 74:27:10:02 lists the categories, including rubble disposal, construction and demolition debris, and sludge disposal. It also allows other categories that meet the general permit criteria. DANR must authorize each facility before it accepts any waste under a general permit.

ARSD 74:27 has no separate beneficial use approval. Ask DANR’s Solid Waste Section how the rules apply to the sand, the receiving site, and the proposed use.

Applying to DANR

Who files: the person who will build or operate the receiving facility applies for the permit.
How: use DANR’s application form for the facility type. Most forms work for an individual permit or for authorization under a general permit.
Fees: ARSD 74:27:08:03 sets fees by facility size. Type I is $5,000, Types IIA and IIB are $500, Type III is $250, and Type IV has no fee.
Size: facility type depends on tons received each year. A Type IV facility receives less than 500 tons a year.
Review: DANR reviews the application and recommends a decision. It publishes the recommendation for a 30-day public comment period. If no one contests it, the recommendation becomes final.
Before you apply: applicants may schedule a meeting with DANR to discuss application requirements (ARSD 74:27:08:05).

DANR Solid Waste Section: (605) 773-3153.

Hazardous waste determination

South Dakota adopts the federal hazardous waste rules by reference in ARSD 74:28:21:01.01. It covers 40 CFR Parts 124, 144, 260–268, 270, 273, and 279 as in effect on July 1, 2022.

The generator standards are in ARSD 74:28:23:01, which applies 40 CFR Part 262. DANR’s Hazardous Waste Section assigns generator identification numbers. Small quantity generators re-notify DANR every four years.

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

Make the determination at the point of generation, before mixing or dilution. Repeat it if the waste may have changed.
Check whether the waste is excluded from the hazardous waste rules.
Check whether it matches a listed hazardous waste.
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, DANR, 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:

TCLP regulatory levels, RCRA metals
Contaminant	EPA waste code	Limit (mg/L)
Arsenic	D004	5.0
Barium	D005	100.0
Cadmium	D006	1.0
Chromium	D007	5.0
Lead	D008	5.0
Mercury	D009	0.2
Selenium	D010	1.0
Silver	D011	5.0

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.

Ask DANR what analyses it needs for the receiving facility’s permit before you sample.

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.

DANR reviews each receiving facility through its permit. Check any destination and proposed use with DANR before scheduling delivery.

Confirm the receiving facility holds a permit or general permit authorization that covers your sand. DANR issues each authorized general permit operator a certificate and letter of authorization. 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. A site used to store solid waste is a solid waste facility, so plan pickup to avoid long storage.

Keep the waste determination, lab reports, DANR permits or authorizations, and the receiving site’s acceptance together. Record tonnage shipped, dates, and destinations. Keep determination records for at least three years.

Before pickup

Identify the alloys cast, sand and binder systems, separate streams, monthly volume, and plant location.
Make the hazardous waste determination and complete the required tests.
Choose a destination and get its material specifications.
Confirm the destination’s DANR permit or general permit authorization covers the sand and use.
Get written acceptance and arrange pickup.

Common questions

Is a passing TCLP test enough?

No. It answers a toxicity question for the substances tested. The full waste determination, DANR’s permit requirements, and the receiving site’s specifications still apply.

Does EPA’s risk assessment approve our sand?

No. It supports three soil-related uses for silica-based sand from iron, steel, and aluminum foundries. DANR still decides each use in South Dakota.

Does a general permit for another material cover spent sand?

Each general permit covers a specific category of waste handling. DANR must authorize each facility before it accepts waste, and a copy of a general permit is not proof of authorization.

What does a permit application cost?

Fees run from no fee for a Type IV facility to $5,000 for a Type I facility (ARSD 74:27:08:03).

How does DANR decide on a permit?

DANR reviews the application and publishes its recommendation for 30 days of public comment. An uncontested recommendation becomes final.

When do we need to test again?

Repeat the determination when the waste may have changed, such as a new alloy, binder, or process. Follow any conditions in the receiving facility’s permit.