19 unchanged sentences
Northern White frac sand is found in poorly cemented Cambrian and Ordovician sandstones and in unconsolidated alluvial deposits locally derived from these sandstones.
−Removed: All of our frac sand facilities are located in Wisconsin, with our Taylor facilities located in Jackson County, our Piranha facilities located in Barron County and our Muskie facilities located in Pierce County.
−Removed: Our frac sand facilities consist of three dry plants with a total permitted capacity of 5.7 million tons of sand per year, and two wet plants, with a total permitted capacity of 8.7 million tons of sand per year, that supply two of the dry plants with Northern White silica sand, which we believe is some of the highest quality raw frac sand available.
−Removed: Our Muskie plant in Pierce County, Wisconsin is currently idled.
+Added: All of our frac sand facilities are located in Wisconsin, with our Taylor facilities located in Jackson County and our Muskie facilities located in Pierce County.
+Added: As of December 31, 2025, our frac sand facilities consist of two dry plants with a total permitted capacity of 3.1 million tons of sand per year, and two wet plants, with a total permitted capacity of 3.9 million tons of sand per year, that supply two of the dry plants with Northern White silica sand, which we believe is some of the highest quality raw frac sand available.
+Added: Our Piranha plant, which had a permitted capacity of 2.6 million tons of sand per year and a wet plant with a capacity of 4.7 million tons of sand per year was sold in September 2025.
+Added: Our Muskie plant in Pierce County, Wisconsin has been idled since September 2018 and was subsequently sold in January 2026.
Our frac sand facilities operate seasonally from March or April through October or November depending on both weather and material demand.
2 unchanged sentences
mining, wet plant operations and dry plant operations.
−Removed: All mining activities take place in an open pit environment, whereby we remove the topsoil, which is set aside, and then remove other non-economic minerals, or “overburden,” to expose the sand deposits.
−Removed: A third-party contractor then “bumps” the sand using explosives on the mine face,
−Removed: which causes the sand to fall into the pit, where it is then carried by truck or conveyor to the wet plant operations.
+Added: All mining activities take place in an
+Added: open pit environment, whereby we remove the topsoil, which is set aside, and then remove other non-economic minerals, or “overburden,” to expose the sand deposits.
+Added: A third-party contractor then “bumps” the sand using explosives on the mine face, which causes the sand to fall into the pit, where it is then carried by truck or conveyor to the wet plant operations.
At our wet plants, the mined sand goes through a series of processes designed to separate the sand from unusable materials.
10 unchanged sentences
Our Muskie location has an indoor wash facility, which is capable of being run year-round.
−Removed: Our Taylor and Piranha mines are located in western Wisconsin, near an estimated combined population of over 350,000 people.
+Added: Both the Taylor and Piranha mines are located in western Wisconsin, near an estimated combined population of over 350,000 people.
Both sites are accessible via a well-developed network of primary and secondary roads, which offer direct access to the mines and processing facilities and are open year-round.
−Removed: Our Taylor facilities have access to the Canadian National rail network, while our Piranha facilities have access to the Union Pacific rail network.
+Added: Our Taylor facilities have access to the Canadian National rail network, while our Piranha facilities had access to the Union Pacific rail network.
Both operations have readily available access to requisite electrical power, natural gas and water.
5 unchanged sentences
As of December 31,
−Removed: 2024 2023 2022
Plant Location
Taylor in Jackson County, Wisconsin 525 492
−Removed: Piranha in Barron County, Wisconsin (a)
+Added: Piranha in Barron County, Wisconsin 136 53
Total 661 545
−Removed: Decline in 2024 due to lower sales volumes.
Mineral Resources and Reserves
8 unchanged sentences
This recovery factor accounts for removal of out-sized (i.e., larger than 20-mesh and smaller than 100-mesh) sand and losses in the wet and dry processing plants due to minor inefficiencies.
−Removed: We do not have any reportable frac sand resources excluding those converted to frac sand proven reserves for the Taylor and Piranha mines.
−Removed: Any frac sand within the defined boundaries of the Taylor and Piranha mines which is not reported as frac sand reserves are not considered to have potential economic viability.
+Added: We do not have any reportable frac sand resources excluding those converted to frac sand proven reserves for the Taylor mine.
+Added: Any frac sand within the defined boundaries of the Taylor mine which is not reported as frac sand reserves are not considered to have potential economic viability.
Therefore, they are not reportable as frac sand resources.
Further, as we do not own any mineral rights for the Muskie property, but, rather, own only the surface rights to the processing plants, we do not (and do not expect to ever) report any reserves attributable to our Muskie property.
−Removed: Boyd updates our reserve estimates annually, making necessary adjustments for operations at each location during the year and
−Removed: additions or surveying, drill core analysis and other tests to confirm the quantity and quality of the reserves.
−Removed: The following table presents our estimated frac sand reserves for the Taylor and Piranha mines as of December 31, 2024 (amounts in thousands):
+Added: Boyd updates our reserve estimates
+Added: annually, making necessary adjustments for operations at each location during the year and additions or surveying, drill core analysis and other tests to confirm the quantity and quality of the reserves.
+Added: The following table presents our estimated frac sand reserves for the Taylor mine as of December 31, 2025 (amounts in thousands):
Mine Reserves Category Total Reserves (1)(2)
Taylor Proven 22,113
−Removed: Piranha Proven 36,650
−Removed: Pricing data based on the weighted average projected sales price for sand of $19.73 per ton for Taylor ’ s operations and $18.59 for Piranha ’ s operations.
−Removed: Boyd has determined that all reportable mineral resources for the Taylor and Piranha mines are categorized as proven reserves as the areas are well explored and exhibit acceptable drill hole data spacing to be classified as measured resources.
+Added: Pricing data based on the weighted average projected sales price for sand of $20.84 per ton for Taylor ’ s operations.
+Added: Boyd has determined that all reportable mineral resources for the Taylor mine are categorized as proven reserves as the areas are well explored and exhibit acceptable drill hole data spacing to be classified as measured resources.
We categorize our sand properties in accordance with the SEC definition in subpart 1300 of Regulation S-K.
19 unchanged sentences
Surface and Mineral Rights
−Removed: For each of our Taylor and Piranha frac sand facilities, we own surface and mineral rights.
+Added: For our Taylor sand facility, we own surface and mineral rights.
For our Muskie sand facility, we own surface rights.
1 unchanged sentence
Our Taylor operation is located less than one mile northwest of the town of Taylor, in Jackson County, Wisconsin and encompasses a total of approximately 393 acres.
−Removed: Approximately 148 acres of frac sand resources remain on this
+Added: Approximately 148 acres of frac sand resources remain on this property.
We own in fee numerous land parcels which comprise the processing plant site, mineral resource areas and rail loadout facility.
1 unchanged sentence
Our Taylor operation commenced mining operations in 2012.
−Removed: We acquired the Taylor operation in June 2017 when we acquired Sturgeon Acquisitions, LLC.
+Added: We acquired the Taylor
+Added: operation in June 2017 when we acquired Sturgeon Acquisitions, LLC.
The total net book value of the Taylor operation’s real property and fixed assets as of December 31, 2025, was $20.1 million.
17 unchanged sentences
The decrease from 2024 to 2025 is primarily attributed to depletion by mining 0.5 million tons of sand.
−Removed: Our Piranha operation is located approximately five miles northwest of the town of New Auburn, in Baron County, Wisconsin and encompasses a total of approximately 608 acres.
−Removed: The current estimated mineable area is approximately 313 acres, or 52% of the total property, after observing setbacks, right of ways, processing areas and other non-mining acreage.
−Removed: We own 100% of the surface and mineral rights.
−Removed: Our dry plant and loadout is also located in Baron County and is approximately one mile east of the mine and wet processing facility.
−Removed: We acquired the Piranha operation on May 26, 2017 from Chieftain Sand and Proppant LLC (Chieftain).
−Removed: Under Chieftain, the property commenced mining operations in August 2012.
−Removed: In January 2018, we purchased the Conoboy tract, which is adjacent to a tract of land previously mined by Chieftain.
−Removed: The total net book value of the Piranha operation’s real property and fixed assets as of December 31, 2024 was $12.3 million.
−Removed: The site contains 36.7 million tons of proven recoverable proppant sand reserves as of December 31, 2024, based on estimates prepared by John T.
−Removed: Our Piranha wet plant, which is adjacent to the mine, can process up to 4.7 million tons of wet sand per year and is located two miles from our Piranha dry plant, to which we have year-round trucking access.
−Removed: As of December 31, 2024, the dry plant facility had a rated production capacity of 2.6 million tons per year.
−Removed: Our current air permit allows us to produce up to 3.5 million tons per year of finished product.
−Removed: Our Piranha facility includes a 150 ton per hour natural
−Removed: gas fired fluid bed dryer and a 200 ton per hour natural gas fluid bed dryer as well as seven high-capacity screeners capable of producing 2.6 million tons of frac sand per year.
−Removed: During the year ended December 31, 2024, our Piranha facility produced 0.1 million tons of sand.
−Removed: Our finished product is loaded directly into railcars.
−Removed: Our Piranha facility is capable of storing up to 400 railcars.
−Removed: We estimate an overall product yield (after mining and processing losses) of approximately 79% for the Piranha mine.
−Removed: Boyd utilized post March 31, 2017 production data we provided, in conjunction with other data, to reconcile the estimate from the March 31, 2017 volumetric estimate to December 31, 2024.
−Removed: The following table presents a summary of our mineral reserves for the Piranha mine as of December 31, 2024, together with a comparison to the reserves as of the end of the preceding fiscal year and an explanation of any material changes.
−Removed: Piranha Mine – Summary of Reserves (1)(2) (Thousands of Tons)
−Removed: Reserves Category December 31, 2024 December 31, 2023 Change % Change
−Removed: Proven 36,650 36,706 (56) — %
−Removed: Pricing data based on the weighted average projected sales price for sand of $18.59 per ton.
−Removed: Boyd has determined that all reportable mineral resources for the Piranha mine are categorized as proven reserves as the area is well explored and exhibit acceptable drill hole data spacing to be classified as a measured resource.
−Removed: The decrease from 2023 to 2024 is primarily attributed to depletion by mining 0.1 million tons of sand.
Our Muskie facility is located in Plum City, Wisconsin and encompass a total of approximately 40 acres.
3 unchanged sentences
The facility has a 100 ton per hour natural gas fired fluid bed dryer as well as six high-capacity screeners that are capable of producing 0.9 million tons per year.
−Removed: As a result of adverse market conditions, production at our Muskie facility has been idled since September 2018.
+Added: As a result of adverse market conditions, production at our Muskie facility has been idled since September 2018 and was subsequently sold in January 2026.
When operating, our finished product is transported via truck to a third-party facility with rail access.
2 unchanged sentences
Muskie was contributed to Mammoth in November 2014.
−Removed: The total net book value of the Muskie operation’s real property and fixed assets as of December 31, 2024, was $4.5 million.
+Added: As of December 31, 2025, the real property and fixed assets associated with the Muskie operation had no remaining carrying value.
Our corporate headquarters are located at 14201 Caliber Drive, Suite 300, Oklahoma City, Oklahoma 73134.
−Removed: We currently own 9 properties, four located in Wisconsin, four located in Ohio and one located in Texas, which are used for field offices, yards, production plants or housing.
+Added: We currently own 5 properties, one located in Wisconsin, three located in Ohio and one located in Texas, which are used for field offices, yards, production plants or housing.
In addition to our headquarters, we also lease 6 properties that are used for field offices, yards or transloading facilities for frac sand.
1 unchanged sentence
Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.