# PCS MT 002 Biochar Carbon Removal & Storage\_v1.0

## Document Control

### Document identification

* **Document code:** PCS-MT-002
* **Title:** Biochar Carbon Removal & Storage Methodology
* **Scope:** Biochar carbon removal projects converting eligible biomass to biochar via controlled thermochemical processes (e.g., pyrolysis/gasification) with eligible storage/application pathways where permanence criteria are met
* **Crediting outcome:** Carbon removals (tCO₂e) attributable to stable biochar carbon storage, net of project emissions and leakage

### Version history and change log

**Table DC-1. Revision history**

| Version | Date | Status | Summary of changes              | Prepared by     | Approved by |
| ------- | ---- | ------ | ------------------------------- | --------------- | ----------- |
| v1.0    | TBD  | Draft  | Release for public consultation | PCS Secretariat | TBD         |

### Superseded versions

No superseded versions for v1.0.

### Governance note on versioning and archiving

Only the latest approved version of this methodology shall be used for new project registrations. Superseded versions shall be archived and retained for traceability, including for projects registered under earlier versions where applicable, consistent with PCS governance rules.

## Purpose and scope summary

### Purpose

PCS-MT-002 defines eligibility criteria, quantification rules, monitoring requirements, and permanence safeguards for biochar projects seeking carbon removal credits, ensuring removals are real, additional, measurable, and durable while accounting for emissions associated with biomass sourcing, processing, production, transport, and end use.

### Scope summary

This methodology applies to projects that convert eligible biomass feedstocks into biochar using controlled thermochemical processes and store/apply biochar in a manner that demonstrably limits oxidation and carbon loss.

### Methodology overview (how the quantification works)

Net carbon removal is quantified ex-post for each monitoring period. The methodology sets the baseline durable carbon removal to zero; credited removals arise exclusively from project activities that convert biomass into stable biochar and store/apply it to limit oxidation.

Gross removals are calculated from stable biochar carbon, converted to CO₂e using the molecular weight ratio of CO₂ to C; project emissions are deducted, and leakage is included where material and attributable.

Only positive net values are eligible for issuance for the monitoring period.

### Normative references

Where there is a conflict, the higher-level PCS governing document prevails unless PCS explicitly states otherwise.

**Table NR-1. Normative references**

| Document code | Title                                                   | Role in this methodology                                    |
| ------------- | ------------------------------------------------------- | ----------------------------------------------------------- |
| PCS-FR-001    | Program Framework                                       | Program principles and governance expectations              |
| PCS-MN-002    | Program Manual                                          | Program processes, roles, and operational rules             |
| PCS-PS-004    | Project Standard                                        | Project eligibility, boundary, additionality, MRV alignment |
| PCS-VVS-005   | Validation & Verification Standard                      | VVB requirements for validation/verification                |
| PCS-ESS-006   | Environmental & Social Safeguards Standard              | Safeguards requirements                                     |
| PCS-SDG-007   | Sustainability & SDG Integrity Standard                 | SDG integrity / contribution claims                         |
| PCS-DC-008    | Avoidance of Double Counting & Corresponding Adjustment | Claim integrity / Article 6 alignment                       |
| PCS-MD-012    | Methodology Development Standard                        | Controls for methodology use/updates/deviations             |
| PCS-PP-013    | Program Processes                                       | Procedural governance controls                              |
| PCS-CN-003    | Biochar Stability Metrics                               | Stability metrics and application in quantification         |
| PCS-CN-004    | Stability vs Permanence                                 | Boundary between stability and permanence obligations       |
| PCS-CN-005    | Evidence Sufficiency                                    | Conservative defaults and treatment of data gaps            |

**Internal consistency note (important):**

PCS-MT-002 text currently cites CN codes for stability/evidence in a way that may be offset from your current file names (e.g., it references “PCS-CN-002 / CN-003 / CN-004” in places). Before finalizing, align all cross-references to the current PCS CN numbering you’re using (CN-003 / CN-004 / CN-005).

## Chapter 1 - Introduction and Scope

### 1.1 Background

1. Biochar is a carbon-rich solid material produced through the thermochemical conversion of biomass under oxygen-limited conditions. When produced from sustainably sourced biomass and managed in a manner that prevents rapid oxidation, biochar enables the conversion of short-cycle biogenic carbon into a chemically stable form capable of persisting for decades to centuries. This characteristic allows biochar systems to function as a **durable atmospheric carbon removal pathway**.
2. Unlike energy-focused biomass systems, biochar methodologies prioritize long-term carbon storage as the primary mitigation outcome. Energy co-products may occur during production, but the climate benefit claimed under this methodology arises exclusively from the stable sequestration of carbon in biochar, not from fossil energy displacement.
3. This methodology establishes a conservative and scientifically grounded framework for quantifying net atmospheric carbon removal achieved through eligible biochar projects under the Planetary Carbon Standard.

### 1.2 Purpose of the Methodology

4. The purpose of PCS-MT-002 is to define eligibility criteria, quantification rules, monitoring requirements, and permanence safeguards for biochar projects seeking carbon removal credits. The methodology ensures that credited removals are real, additional, measurable, and durable, while accounting for emissions associated with biomass sourcing, processing, biochar production, transport, and end use.
5. This document is the controlling technical reference for biochar projects. Any associated calculation tool implements, but does not supersede, the rules defined herein.

### 1.3 Scope of Application

6. This methodology applies to projects that convert eligible biomass feedstocks into biochar using controlled thermochemical processes such as pyrolysis or gasification, where the resulting biochar is stored or applied in a manner that demonstrably limits oxidation and carbon loss.
7. Eligible storage and application pathways include soil application, incorporation into construction materials, land reclamation, mine rehabilitation, and dedicated biochar storage systems, provided permanence criteria are met.
8. This methodology does not apply to:

* Uncontrolled combustion or incidental char formation
* Biomass energy projects without long-term carbon storage
* Fossil-derived carbon materials
* Projects unable to demonstrate biochar stability and traceability

### 1.4 Relationship to PCS Framework

9 PCS-MT-002 is developed in accordance with the PCS Program Framework, Methodology Development Standard, and Validation & Verification Standard. It is aligned with PCS rules on additionality, permanence, conservative accounting, and avoidance of double counting.

Where inconsistencies arise, PCS core standards take precedence over this methodology.

### 1.5 Scientific Basis

10. The methodological approach draws on peer-reviewed research on biochar stability, aromatic carbon structures, hydrogen-to-carbon ratios, oxidation resistance, and observed long-term decay behavior. Conservative assumptions are applied where uncertainty exists, particularly in relation to permanence and degradation rates.
11. Carbon accounting principles align with IPCC treatment of biogenic carbon, with additional constraints applied to ensure that credited removals represent durable atmospheric carbon removal rather than temporary carbon cycling.

### 1.6 Intended Users

12. This methodology is intended for project developers, validation and verification bodies, registry administrators, and technical reviewers with experience in carbon accounting, biomass systems, and negative emissions technologies.

## Chapter 2 - Project Eligibility and Applicability

### 2.1 General Eligibility Conditions

13. A project is eligible under this methodology if it demonstrably converts eligible biomass feedstocks into biochar using a controlled thermochemical process and ensures that the resulting biochar is stored or applied in a manner that provides durable carbon storage.
14. Eligibility is contingent on the project meeting all requirements related to feedstock sourcing, production technology, biochar quality, permanence, monitoring, and verification as defined in this methodology. Projects must demonstrate that carbon removal is the primary mitigation outcome, and that no double counting occurs with energy generation or other mitigation claims.

### 2.2 Eligible Feedstock Categories

15. 1This methodology permits the use of both **residual biomass** and **dedicated biomass**, subject to sustainability and additionality safeguards.

**16. Residual biomass** refers to biomass that arises as a by-product or residue of existing processes and would otherwise be unmanaged, underutilized, or disposed of without intentional carbon sequestration. Examples include agricultural residues, forestry residues, processing by-products, organic waste fractions, and similar materials.

**17. Dedicated biomass** refers to biomass intentionally cultivated or produced for biochar generation. Dedicated biomass is eligible only when the project demonstrates that its production does not cause direct or indirect environmental harm, does not displace food or feed production, and does not lead to land-use change that would negate claimed removals.

18. All feedstocks must be of **biogenic origin**. Fossil-derived materials, peat, or materials with mixed fossil content are not eligible.

### 2.3 Sustainability and Additionality Requirements for Feedstocks

19. For **residual biomass**, the project must demonstrate that the biomass is not diverted from an existing higher-value use that would otherwise result in long-term carbon storage or equivalent climate benefit. Residual biomass must not be sourced in a manner that causes environmental degradation, biodiversity loss, or social harm.
20. For **dedicated biomass**, additional requirements apply. The project must demonstrate that biomass production does not result in deforestation, degradation of natural ecosystems, or conversion of high-carbon or high-biodiversity lands. The project must also demonstrate that biomass cultivation practices are consistent with sustainable land management and do not increase net emissions through fertilizer use, irrigation energy, or soil carbon loss beyond what is accounted for in project emissions.
21. Projects using dedicated biomass must document land tenure, land-use history, and baseline land conditions. Any land-use change emissions attributable to feedstock production must be included in project emissions where applicable.

### 2.4 Eligible Conversion Technologies

22. Eligible projects must use **controlled thermochemical conversion processes** designed to maximize solid carbon retention. Eligible technologies include:

* Pyrolysis systems operated under oxygen-limited conditions
* Gasification systems where solid char is recovered and preserved

23. The technology must allow reliable measurement of biomass input, biochar output, and process conditions. Open burning, uncontrolled combustion, or systems where char formation is incidental are not eligible.
24. Energy co-products generated during conversion are permitted but **must not be credited** under this methodology. Any emissions associated with energy use must be accounted for as part of project emissions.

### 2.5 Biochar Quality and Stability Requirements

25. To be eligible, produced biochar must meet minimum stability criteria demonstrating resistance to rapid degradation. Stability may be demonstrated using recognized indicators such as elemental composition, hydrogen-to-carbon ratios, aromatic carbon content, or other scientifically defensible metrics.
26. Biochar that does not meet minimum stability thresholds cannot be credited. Where multiple stability metrics are available, conservative interpretation must be applied. Stability requirements apply equally to biochar derived from residual and dedicated biomass.

### 2.6 Eligible Storage and Application Pathways

27. Biochar must be stored or applied in a manner that ensures long-term carbon retention. Eligible pathways include soil incorporation, construction material blending, land rehabilitation, mine reclamation, and dedicated storage systems.
28. The project must demonstrate that the selected pathway minimizes oxidation, erosion, or removal of biochar and that management practices support permanence over the credited time horizon.
29. Temporary storage without defined long-term placement is not eligible unless safeguards are in place to prevent reversal.

### 2.7 Excluded Project Types

30. The following project types are not eligible under PCS-MT-002:

* Projects where biochar stability cannot be demonstrated
* Projects relying primarily on fossil-derived inputs
* Projects that claim emission reductions from energy displacement under this methodology
* Projects that intentionally increase biomass harvesting without sustainability controls
* Projects where feedstock sourcing results in net ecosystem carbon loss

### 2.8 Applicability Over the Project Lifetime

31. Eligibility must be maintained throughout the crediting period. Changes in feedstock sourcing, technology, operating conditions, or storage pathways that materially affect emissions or permanence must be assessed and documented.
32. If eligibility conditions are no longer met, credit issuance must be suspended until compliance is restored.

## Chapter 3 - Project Boundary and Sources

### 3.1 Purpose of the Project Boundary

33. The project boundary defines all physical processes, carbon pools, and emission sources that must be included when quantifying net atmospheric carbon removal. A clearly defined boundary ensures completeness, avoids double counting, and enables conservative accounting of both removals and emissions associated with biochar systems.
34. The boundary encompasses upstream activities necessary to produce biochar, the biochar production process itself, downstream handling and storage or application, and any associated emissions that materially influence the net carbon balance.

### 3.2 Physical Boundary

35. The physical boundary includes all facilities, equipment, and activities under the control of the project proponent that are directly involved in:

* Biomass feedstock sourcing and preparation
* Transport of biomass to the conversion facility
* Thermochemical conversion of biomass into biochar
* Collection, processing, and conditioning of biochar
* Transport of biochar to its final storage or application site
* Storage or application of biochar in eligible pathways

36. Where third-party activities are integral to these processes, such activities must be included within the boundary if they are attributable to the project and would not occur in the absence of the project.

### 3.3 Carbon Pools Included

37. The methodology includes the following carbon pools within the project boundary:

* **Atmospheric carbon**, represented by biogenic CO₂ removed during biomass growth
* **Biomass carbon**, contained in residual or dedicated feedstocks
* **Biochar carbon**, representing the stable carbon retained in solid form after conversion

38. The methodology credits only the fraction of biochar carbon that meets defined stability and permanence criteria. Temporary or unstable carbon pools are not credited.
39. Soil organic carbon changes outside the direct influence of biochar application are excluded unless explicitly measured and conservatively accounted for under approved procedures.

### 3.4 Emission Sources Included

40. All material emission sources associated with the project must be included. These typically include emissions from biomass harvesting or collection, preprocessing such as chipping or drying, transport of feedstocks and biochar, energy and fuel use during conversion, and any ancillary processes required to produce and manage biochar.
41. Where dedicated biomass is used, emissions associated with cultivation activities—such as fuel use, fertilizer application, irrigation energy, and land preparation—must be included if they are attributable to the project.
42. Emissions associated with temporary biochar storage, handling losses, or conditioning processes must also be included where relevant.

### 3.5 Emission Sources Excluded

43. The following sources are excluded from the project boundary:

* Emissions from biomass growth, which represent atmospheric CO₂ uptake and are not counted as project emissions
* Emissions from energy co-products where energy is not credited and no displacement claims are made
* Downstream impacts not attributable to the project, such as unrelated land management practices

44. Excluded sources must not materially affect the conservativeness of net removal estimates. If uncertainty exists, the source must be included rather than excluded.

### 3.6 Treatment of Residual Versus Dedicated Biomass

45. For **residual biomass**, the boundary includes collection and transport activities that are incremental to existing practices. Baseline emissions associated with unmanaged decay or disposal are not credited unless explicitly permitted under PCS rules.
46. For **dedicated biomass**, the boundary extends to biomass production activities, including land preparation, cultivation, and harvesting. The project must demonstrate that these activities do not result in net ecosystem carbon loss beyond what is accounted for as project emissions. Any land-use change emissions attributable to feedstock production must be included within the boundary.

### 3.7 Biochar Storage and Application Boundary

47. The boundary includes the biochar storage or application site for the duration relevant to credited permanence. Biochar applied to soils, construction materials, or land rehabilitation sites remains within the accounting boundary for the purposes of permanence assessment and reversal risk management.
48. Projects must define clear custody and control arrangements for biochar after production to ensure that credited material remains traceable and protected against unaccounted losses.

### 3.8 Temporal Boundary

49. The temporal boundary begins with the start of biomass input monitoring and extends through biochar production, storage or application, and the credited permanence period. Monitoring and reporting must align with defined monitoring periods, while permanence obligations extend beyond credit issuance as specified in later chapters.

### 3.9 Boundary Consistency Over Time

50. The project boundary must remain consistent throughout the crediting period. Any material change to feedstock sourcing, production technology, logistics, or storage pathways that affects emissions or permanence must be assessed, documented, and, where necessary, approved prior to continued credit issuance.

## Chapter 4 - Baseline Scenario

### 4.1 Purpose of the Baseline Scenario

51. The baseline scenario defines the greenhouse gas emissions and carbon stock changes that would occur in the absence of the biochar project. For biochar carbon removal pathways, the baseline serves a conservative function: it establishes that, without the project, **no durable atmospheric carbon removal would occur**.
52. This chapter sets out the baseline assumptions applicable to both residual and dedicated biomass feedstocks and explains why baseline removals are set to zero under PCS-MT-002.

### 4.2 General Baseline Principle

53. Under this methodology, the baseline scenario assumes that biomass carbon returns to the atmosphere over short time horizons through natural or managed processes such as decomposition, open or controlled combustion, or short-lived material use. These processes do not result in long-term carbon storage and therefore do not constitute carbon removal.
54. Accordingly, the baseline level of durable carbon storage is conservatively defined as **zero**. All credited carbon removals under this methodology arise exclusively from project activities that convert biomass into stable biochar and store or apply it in a manner that prevents rapid oxidation.
55. This approach avoids speculative assumptions regarding avoided emissions or counterfactual land management practices and ensures environmental integrity.

### 4.3 Baseline Treatment of Residual Biomass

56. For residual biomass, the baseline assumes that, in the absence of the project, the material would be subject to unmanaged or managed degradation, combustion, or disposal pathways that do not result in long-term carbon storage.
57. The methodology does not credit avoided methane emissions, avoided open burning, or avoided fossil fuel displacement associated with alternative treatment of residual biomass. This conservative treatment ensures that credited removals reflect only the durable sequestration achieved through biochar formation and storage.
58. biomass that is already subject to long-term carbon storage or regulated sequestration pathways in the baseline is not eligible unless the project demonstrates additional durable storage beyond the baseline condition.

### 4.4 Baseline Treatment of Dedicated Biomass

59. For dedicated biomass, the baseline assumes that the biomass would not have been produced in the absence of the project. Therefore, baseline carbon storage remains zero, and all carbon stored in biochar is attributable to project activities.
60. However, emissions associated with biomass cultivation, harvesting, and processing must be fully accounted for within project emissions. This includes emissions from machinery, fertilizers, irrigation energy, and any other inputs that materially affect the net carbon balance.
61. The methodology explicitly excludes crediting avoided land-use change or avoided emissions associated with hypothetical alternative land uses. This avoids uncertainty and ensures that credited removals are not inflated by speculative counterfactual scenarios.

### 4.5 Exclusion of Avoided Emission Baselines

62. This methodology does not permit baseline scenarios based on avoided emissions such as avoided decay, avoided landfill disposal, avoided burning, or avoided fossil fuel use. While such emissions may be relevant in other mitigation pathways, their inclusion here would risk double counting and undermine the clarity of carbon removal accounting.
63. By excluding avoided emission baselines, PCS-MT-002 maintains a clear distinction between emission reduction methodologies and carbon removal methodologies.

### 4.6 Baseline Stability and Temporal Considerations

64. The baseline scenario is fixed and does not vary over time. It does not require periodic reassessment or updating because it is defined by the absence of durable carbon storage rather than by dynamic system behavior.
65. This fixed baseline simplifies monitoring, enhances transparency, and prevents baseline manipulation over the project lifetime.

### 4.7 Conservativeness and Environmental Integrity

66. The baseline approach adopted under PCS-MT-002 is intentionally conservative. It ensures that credits are issued only for carbon that is demonstrably converted into a stable form and retained over long time horizons.
67. Any uncertainty regarding baseline conditions must be resolved by maintaining the baseline at zero durable carbon storage. This principle underpins the environmental integrity of the methodology and aligns with best practices for carbon removal accounting.

## Chapter 5 - Biochar Production and Characterization

### 5.1 Purpose of Biochar Production and Characterization Requirements

68. This chapter defines the technical requirements governing the production of biochar and the characterization of its physical and chemical properties for the purpose of carbon removal accounting. The objective is to ensure that only biochar with demonstrable stability, traceable origin, and verifiable carbon content is eligible for crediting under PCS-MT-002.
69. Biochar characterization under this methodology serves two core functions: determining the quantity of carbon retained in solid form during conversion, and establishing the fraction of that carbon that can be considered stable over long time horizons.

### 5.2 Eligible Biochar Production Technologies

70. Eligible biochar must be produced through **controlled thermochemical conversion** of biomass under oxygen-limited conditions. The conversion process must be designed and operated to intentionally maximize the retention of carbon in solid form.
71. Eligible technologies include pyrolysis systems and gasification systems where solid char is deliberately recovered and preserved. Process conditions must be measurable and controllable, including temperature range, residence time, and oxygen availability.
72. Technologies where char formation is incidental or uncontrolled, such as open burning or conventional biomass combustion, are not eligible. The project must demonstrate that biochar production is an intentional and primary output of the system.

### 5.3 Biomass Input Measurement and Traceability

73. All biomass inputs used for biochar production must be measured, recorded, and traceable. Biomass mass must be determined using calibrated measurement systems appropriate to the scale of operation.
74. Feedstock records must identify the biomass category, origin, and whether the material is residual or dedicated. For mixed feedstocks, projects must demonstrate how input quantities are allocated across categories and how characterization results remain representative.
75. Traceability must be maintained from biomass input through conversion to biochar output, ensuring that credited biochar can be linked to eligible feedstock sources.

### 5.4 Biochar Yield Determination

76. Biochar yield represents the mass of biochar produced per unit mass of dry biomass input. Yield must be determined using direct measurement of biochar output and documented input quantities.
77. Yield calculations must be based on dry mass or be corrected for moisture content where measurements are taken on an as-received basis. Where continuous production occurs, yield may be determined on a batch or averaged basis, provided variability is monitored and documented.
78. Only biochar physically recovered and retained for eligible storage or application pathways may be included in yield calculations. Losses during handling, conditioning, or transport must be excluded from credited quantities.

### 5.5 Biochar Carbon Content Determination

79. The carbon content of biochar must be determined using laboratory analysis or equivalent standardized methods. Measurements must quantify total carbon on a dry basis and be representative of the biochar batches produced during the monitoring period.
80. Where biochar production conditions vary materially, projects must demonstrate that carbon content measurements remain representative or conduct additional testing as necessary. Default values may only be used where permitted by PCS rules and must be conservative.
81. Carbon content results form the basis for calculating gross carbon stored prior to the application of stability discounts.

### 5.6 Biochar Stability Indicators

82. Only the fraction of biochar carbon considered stable over long time horizons is eligible for crediting. Stability must be demonstrated using scientifically defensible indicators linked to resistance against biological and chemical degradation.
83. Accepted indicators may include elemental ratios, such as hydrogen-to-organic-carbon ratios, aromatic carbon content, or other recognized proxies for recalcitrance. Where multiple indicators are available, the most conservative interpretation must be applied.
84. Biochar that does not meet minimum stability criteria is not eligible for crediting under this methodology.

***Note:***\_ The interpretation and application of biochar stability indicators, including acceptable indicator types, conservative interpretation, and documentation requirements, shall be conducted in accordance with\_***PCS-CN-002 — Biochar Stability Metrics and Application in Quantification**.*

***Note:***\_ Stability indicators support conservative classification at quantification and shall not be interpreted as permanence assurances, consistent with\_***PCS-CN-003 — Stability vs Permanence: Boundary, Obligations, and Reversals**.*

***Note:***\_ Evidence used to support biochar characterization and stability indicators shall meet the sufficiency requirements and conservative treatment principles clarified in\_***PCS-CN-004 — Evidence Sufficiency, Conservative Defaults, and Data Gaps***

### 5.7 Stability Classification and Creditable Fraction

85. Biochar must be assigned to a stability class that determines the fraction of carbon eligible for crediting. Stability classification must be based on measured indicators or conservative default classes where testing is limited.
86. The methodology applies stability discounts at the time of crediting, rather than modeling future decay. This approach avoids uncertainty associated with long-term decay modeling and ensures conservative accounting.
87. The credited carbon fraction must reflect only the portion of biochar carbon that is demonstrably stable.

### 5.8 Treatment of Non-Eligible Biochar Fractions

88. Biochar fractions that fail to meet stability requirements, are lost prior to storage or application, or are used in non-eligible pathways must be excluded from credited quantities.
89. Ash, fines, or other residues without demonstrable carbon stability are not eligible. Projects must document handling practices to ensure clear separation between eligible and non-eligible fractions.

### 5.9 Batch Identification and Recordkeeping

90. Biochar must be produced and tracked in identifiable batches or continuous production segments that allow linkage between feedstock inputs, production conditions, characterization results, and final storage or application.
91. Records must include production dates, quantities, characterization results, and destination of biochar. These records form a critical component of monitoring and verification.

### 5.10 Conservative Treatment and Updates

92. If uncertainty exists regarding biochar yield, carbon content, or stability, the project must apply conservative assumptions that reduce credited quantities. Updated characterization may be required if production conditions or feedstocks change materially.
93. All characterization procedures and results must be documented and made available for verification.

## Chapter 6 - Quantification of Net Carbon Removal

### 6.1 Purpose of the Quantification Framework

94. This chapter defines the rules and equations used to quantify **net atmospheric carbon removal** achieved by biochar projects. Quantification under PCS-MT-002 is designed to be conservative, transparent, and reproducible, ensuring that credited removals represent durable carbon storage after accounting for all relevant emissions and leakage.
95. The methodology credits only the fraction of carbon that is demonstrably converted into stable biochar and retained in eligible storage or application pathways, net of project-related emissions.

### 6.2 Overview of Quantification Logic

96. Net carbon removal for a monitoring period is calculated as the difference between credited stable biochar carbon and total project-related greenhouse gas emissions, adjusted for any applicable leakage.
97. The general form of the calculation is:
98. where all terms are expressed in units of CO₂ equivalent.
99. Baseline carbon removal is zero, as defined in Chapter 4.

### 6.3 Gross Biochar Carbon Produced

100. Gross biochar carbon represents the total amount of carbon contained in eligible biochar produced during the monitoring period, prior to stability adjustment.
101. Gross biochar carbon is calculated as:
102. where:

* is the dry mass of eligible biochar produced, and
* is the measured carbon content of the biochar on a dry basis.

103. Only biochar quantities that are physically recovered, traceable, and directed to eligible storage or application pathways may be included.

***Note:***\_ All parameters used for quantification shall be supported by sufficient evidence. Where evidence is incomplete or unavailable, conservative defaults or exclusion shall be applied in accordance with\_***PCS-CN-004 — Evidence Sufficiency, Conservative Defaults, and Data Gaps**.*

### 6.4 Determination of Stable Biochar Carbon

104. Not all biochar carbon is assumed to remain stored over long time horizons. A **stability fraction** is applied to reflect the proportion of carbon that is resistant to degradation.
105. Stable biochar carbon is calculated as:
106. where is derived from stability classification based on indicators defined in Chapter 5.
107. Stability fractions must be conservative and based on measured indicators or approved default classes. No future decay modeling is applied within the crediting calculation.

*Note: Stability fractions applied for the purpose of quantification shall reflect conservative classification of durable biochar carbon and shall be applied in accordance with**PCS-CN-002 — Biochar Stability Metrics and Application in Quantification**.*

*Note: For the avoidance of doubt, the application of stability fractions at the time of quantification does not affect post-crediting permanence obligations. The boundary between stability and permanence is clarified in**PCS-CN-003 — Stability vs Permanence: Boundary, Obligations, and Reversals**.*

**6.5 Conversion to CO₂ Equivalent**

108. Stable biochar carbon is converted to carbon dioxide equivalent using the molecular weight ratio of CO₂ to carbon:
109. This represents the gross atmospheric carbon dioxide removal attributable to stable biochar storage.

### 6.6 Project Emissions

110. Project emissions include all greenhouse gas emissions attributable to project activities within the defined project boundary. These emissions must be quantified and deducted from gross removals.
111. Project emissions may include, but are not limited to:

* Fuel and energy use during biomass collection, preparation, and transport
* Energy and auxiliary fuel use during thermochemical conversion
* Electricity or fuel use for biochar handling, conditioning, and storage
* Emissions associated with dedicated biomass cultivation where applicable

112. Project emissions are calculated as:
113. where represents the activity data for emission source , and is the corresponding emission factor.
114. Only fossil greenhouse gas emissions are included. Biogenic CO₂ emissions from biomass processing are excluded, consistent with PCS treatment of biogenic carbon.

### 6.7 Leakage Emissions

115. Leakage emissions include greenhouse gas emissions occurring outside the project boundary that are attributable to project implementation and would not otherwise occur.
116. Leakage may arise from transport activities performed by third parties, preprocessing of biomass or biochar outside the project facility, or displacement of biomass to alternative uses that increase emissions elsewhere.
117. Leakage emissions are included only where they are material and attributable. Where uncertainty exists, conservative inclusion is required.
118. Leakage emissions are calculated using the same activity data and emission factor approach as project emissions.

### 6.8 Net Carbon Removal Calculation

119. Net carbon removal for the monitoring period is calculated as:
120. Only positive values of are eligible for credit issuance. Negative or zero values result in no issuance for the monitoring period.

### 6.9 Treatment of Uncertainty and Conservativeness

121. Where uncertainty exists in measurements of biochar mass, carbon content, stability, or emissions, conservative assumptions must be applied that reduce credited removals.
122. If data gaps occur, reconstruction may be permitted only where supported by robust evidence and conservative assumptions. Otherwise, affected quantities must be excluded from crediting.

### 6.10 Aggregation and Reporting

123. Quantification is performed at the monitoring-period level and may be aggregated annually or across crediting periods as required by PCS reporting rules.
124. All intermediate values, assumptions, and applied stability fractions must be transparently reported and traceable to monitoring data and evidence records.

## Chapter 7 - Permanence and Reversal Risk

### 7.1 Purpose of Permanence Provisions

125. This chapter defines how permanence is addressed for biochar-based carbon removal and establishes the rules for identifying, monitoring, and managing reversal risks. Permanence provisions ensure that credited removals represent durable atmospheric carbon storage and that any loss of stored carbon is appropriately identified and treated.
126. The approach adopted under PCS-MT-002 is conservative and precautionary, reflecting scientific uncertainty while avoiding speculative modeling of long-term decay.

*Note: For the avoidance of doubt, permanence obligations apply independently of stability classification. Stability applied at quantification does not reduce, replace, or modify permanence obligations or reversal treatment. The distinction between stability and permanence is clarified in**PCS-CN-003 — Stability vs Permanence: Boundary, Obligations, and Reversals**.*

### 7.2 Definition of Permanence for Biochar

127. For the purposes of this methodology, permanence refers to the **long-term retention of carbon in biochar in a form that resists biological, chemical, and physical degradation** over climate-relevant time horizons.
128. Permanence is demonstrated through a combination of:

* Biochar intrinsic stability, as defined by material properties
* The characteristics of the storage or application environment
* Ongoing management practices that prevent oxidation, removal, or disturbance

129. Credited removals must be consistent with a long-term storage horizon aligned with PCS carbon removal principles.

*Note: For the avoidance of doubt, stability classification applied at the time of quantification is distinct from permanence obligations. The interpretation of stability versus permanence is clarified in**PCS-CN-002 — Biochar Stability Metrics and Application in Quantification**.*

### 7.3 Permanence Time Horizon

130. PCS-MT-002 applies a permanence expectation consistent with long-duration carbon removal. Rather than modeling decay over time, the methodology applies **up-front stability discounts** to reflect conservative estimates of long-term retention.
131. Once credited, stable biochar carbon is assumed to remain stored unless evidence of loss or disturbance arises. This approach avoids uncertainty associated with projecting degradation rates far into the future.

### 7.4 Reversal Risk Categories

132. Reversal risk refers to the potential loss of stored biochar carbon resulting in its return to the atmosphere. Reversal risks under this methodology are classified into the following categories:

**133. Physical disturbance risks**, including erosion, excavation, fire, or relocation of biochar from storage or application sites.

**134. Chemical or biological degradation risks**, where environmental conditions accelerate oxidation or microbial breakdown beyond conservative assumptions.

**135. Operational and management risks**, including improper storage, mishandling, or failure to follow approved application practices.

**136. Force majeure risks**, such as extreme natural events beyond the control of the project proponent.

### 7.5 Risk Mitigation Measures

137. Projects must identify and implement measures appropriate to the selected storage or application pathway to minimize reversal risk. Measures may include controlled incorporation depths, protective coverings, restricted access, erosion controls, fire management practices, and contractual safeguards governing biochar custody.
138. Risk mitigation measures must be proportionate to the risk profile of the project and supported by operational procedures and monitoring.

### 7.6 Monitoring of Permanence

139. Projects must monitor biochar storage or application sites to detect material changes that could affect permanence. Monitoring may include visual inspections, documentation of land management activities, and confirmation that biochar remains in the approved storage or application pathway.
140. Monitoring frequency and methods must be sufficient to identify potential reversals in a timely manner and must be documented in the monitoring plan.

### 7.7 Treatment of Reversals

141. If a reversal occurs, the project must quantify the amount of biochar carbon affected and report the event promptly. The quantity of carbon lost must be deducted from credited removals in the monitoring period in which the reversal is identified.
142. Intentional reversals or negligence-related losses may result in additional corrective actions as determined by PCS governance rules. Unintentional reversals due to force majeure must still be accounted for, but may be treated differently for compliance purposes depending on PCS provisions.

### 7.8 Temporary Storage and Custody Transfers

143. Where biochar is temporarily stored prior to final application or placement, projects must demonstrate that safeguards are in place to prevent loss, contamination, or misuse. Custody transfers must be documented to ensure traceability and responsibility for permanence obligations.
144. Temporary storage without defined long-term placement is permissible only where risks are demonstrably controlled and time-limited.

### 7.9 Permanence Obligations Beyond Crediting

145. Permanence obligations extend beyond the credit issuance period. Projects remain responsible for monitoring and managing credited biochar for the duration specified by PCS carbon removal rules.
146. Failure to maintain permanence obligations may result in credit invalidation or other corrective actions as defined by PCS governance procedures.

### 7.10 Conservative Treatment and Review

147. Where uncertainty exists regarding permanence or reversal risk, conservative assumptions must be applied. PCS may require additional safeguards or adjustments to credited quantities if new scientific evidence emerges that materially affects permanence assumptions.
148. Projects must remain responsive to such updates while maintaining transparency and integrity.

## Chapter 8 - Monitoring Requirements

### 8.1 Purpose of Monitoring

149. Monitoring under PCS-MT-002 ensures that all data required to quantify net carbon removal, demonstrate permanence, and support verification are collected in a complete, accurate, and traceable manner. Monitoring requirements are designed to support conservative accounting while remaining practical for a wide range of biochar project scales and configurations.
150. All monitoring data must be directly linked to the quantification approach defined in Chapter 6 and the permanence provisions defined in Chapter 7.

### 8.2 Monitoring of Biomass Feedstock Inputs

151. Projects must monitor all biomass feedstocks used for biochar production. Monitoring must capture the quantity, type, origin, and classification of feedstocks as residual or dedicated biomass.
152. Biomass quantities must be measured using calibrated weighing systems or volumetric systems with appropriate conversion factors. Measurements must be recorded for each delivery or batch and aggregated for the monitoring period. Where moisture content varies materially, moisture measurements or corrections must be applied to ensure consistency with dry-mass calculations used in quantification.
153. Feedstock records must clearly identify the source location, feedstock category, and sustainability status. For dedicated biomass, additional records must document land-use status, cultivation practices, and any changes in sourcing over time.

### 8.3 Monitoring of Biochar Production Processes

154. Projects must monitor biochar production processes to ensure that conversion conditions remain consistent with eligible production requirements. Monitoring must include documentation of operating parameters relevant to biochar quality and stability, such as temperature ranges, residence time, and oxygen-limiting conditions.
155. Operational logs must demonstrate that biochar production is intentional and continuous or batch-controlled, rather than incidental. Any deviations from normal operating conditions that could affect yield or stability must be recorded and assessed.

### 8.4 Monitoring of Biochar Output and Yield

156. The quantity of biochar produced must be measured and recorded for each batch or defined production interval. Measurements must distinguish between eligible biochar retained for approved storage or application and any non-eligible fractions, losses, or residues.
157. Biochar mass must be recorded on a dry basis or corrected for moisture content using representative measurements. Yield calculations must reconcile biomass inputs with biochar outputs, accounting for reasonable process losses.
158. Projects must retain records sufficient to allow verifiers to reconstruct yield calculations for each monitoring period.

***Note:**&#x44;ata gaps identified during monitoring shall be treated conservatively and documented. The treatment of data gaps and use of defaults shall follow**PCS-CN-003 — Evidence Sufficiency, Conservative Defaults, and Data Gaps**.*

### 8.5 Monitoring of Biochar Carbon Content and Stability

159. Biochar carbon content must be determined through laboratory analysis or approved equivalent methods. Sampling must be representative of biochar produced during the monitoring period and reflect any variability in feedstocks or production conditions.
160. 1Stability indicators used to determine the stable carbon fraction must be measured at a frequency sufficient to remain representative. At minimum, stability testing must be conducted when production conditions or feedstock types change materially. Where production conditions are stable, periodic testing at defined intervals may be sufficient.
161. All laboratory analyses must include metadata describing sampling procedures, analytical methods, detection limits, and uncertainty ranges.

### 8.6 Monitoring of Biochar Storage and Application

162. Projects must monitor the storage or application of biochar to confirm that credited material is placed and managed in accordance with eligible pathways. Monitoring must document the location, quantity, date, and method of storage or application.
163. For soil or land applications, monitoring must include records of incorporation methods, depth, and land management practices relevant to permanence. For construction materials or dedicated storage, monitoring must document containment measures and custody arrangements.
164. Biochar must remain traceable from production through final placement. Any losses, spills, or deviations must be recorded and assessed for permanence implications.

### 8.7 Monitoring of Project Emissions

165. 1All project-related fossil greenhouse gas emissions must be monitored. This includes emissions from fuel and electricity use during biomass collection, processing, transport, biochar production, handling, and storage.
166. Activity data must be collected using calibrated meters, fuel purchase records, or operational logs. Emission factors must be applied consistently with PCS rules and documented in the monitoring report.
167. Where dedicated biomass is used, emissions from cultivation activities attributable to the project must also be monitored or conservatively estimated.

### 8.8 Monitoring of Leakage Emissions

168. Where leakage is identified as potentially material, projects must monitor relevant activity data outside the direct project boundary. This may include third-party transport distances, preprocessing energy use, or displacement of biomass to alternative uses.
169. Leakage monitoring must be sufficient to support conservative quantification. If leakage cannot be reliably quantified, conservative assumptions must be applied or affected quantities excluded from crediting.

### 8.9 Monitoring Frequency and Data Aggregation

170. Monitoring must be continuous or periodic, as appropriate to each parameter, and aligned with defined monitoring periods. Data must be aggregated consistently for reporting and verification, ensuring that all values used in quantification correspond to the same temporal boundaries.
171. Monitoring systems must be designed to minimize data gaps. Where gaps occur, reconstruction may be permitted only where supported by robust evidence and conservative assumptions.

### 8.10 Data Management and Record Retention

172. All monitoring data must be recorded in a structured and auditable format. Projects must maintain secure data storage systems that prevent unauthorized modification and allow retrieval of historical records.
173. Records must be retained for the duration required by PCS governance rules, including periods extending beyond credit issuance to support permanence obligations.

### 8.11 Monitoring Plan Updates

174. The monitoring plan must be reviewed and updated whenever project conditions change in a manner that could affect data quality, emissions, or permanence. Changes in feedstock sourcing, production technology, storage pathways, or logistics must be reflected in updated monitoring procedures.
175. All updates must be documented and justified prior to implementation.

## Chapter 9 - Quality Assurance and Quality Control (QA/QC)

### 9.1 Purpose of QA/QC Provisions

176. Quality assurance and quality control procedures under PCS-MT-002 are designed to ensure that all data used for quantification of net carbon removal are accurate, complete, conservative, and verifiable. QA/QC provisions reduce the risk of over-crediting, prevent systematic errors, and ensure consistency between monitoring data, calculations, and reported results.
177. QA/QC requirements apply across the entire project lifecycle, including feedstock sourcing, biochar production, characterization, emissions accounting, storage or application, and reporting.

### 9.2 General QA/QC Principles

178. Projects must implement QA/QC procedures that are proportionate to project scale and complexity, while ensuring that environmental integrity is not compromised. Where uncertainty exists, conservative assumptions must be applied.
179. All QA/QC procedures must be documented, consistently applied, and available for review by validation and verification bodies. Deviations from approved procedures must be recorded and justified.

### 9.3 Measurement and Equipment QA/QC

180. All equipment used to measure biomass inputs, biochar outputs, energy use, fuel consumption, and transport distances must be suitable for the intended purpose and maintained in proper working condition.
181. Calibration of weighing systems, meters, and measurement devices must be conducted at regular intervals consistent with manufacturer specifications or applicable standards. Calibration certificates must be retained and referenced in monitoring documentation.
182. Where indirect measurement methods are used, conversion factors must be documented, justified, and applied consistently. Any change in equipment or measurement methodology must be assessed for potential impacts on data comparability.

### 9.4 Laboratory Analysis QA/QC

183. Laboratory analyses used to determine biochar carbon content, elemental composition, and stability indicators must be conducted by competent laboratories using recognized analytical methods.
184. Sampling procedures must ensure representativeness of biochar produced during the monitoring period. Chain-of-custody documentation must be maintained from sample collection through analysis.
185. Laboratory reports must include information on analytical methods, detection limits, quality controls, and uncertainty ranges. Where replicate analyses are conducted, results must be evaluated for consistency, and outliers must be investigated and resolved.
186. If laboratory results are inconsistent or incomplete, conservative values must be applied or affected quantities excluded from crediting.

### 9.5 Data Completeness and Consistency Checks

187. Projects must implement internal checks to confirm that all required monitoring data are complete for each monitoring period. This includes reconciliation of biomass input quantities with biochar output quantities, accounting for reasonable process losses.
188. Consistency checks must verify that biochar yield, carbon content, and stability classifications are aligned with production conditions and feedstock types. Significant deviations from historical averages must be investigated and documented.
189. Energy and fuel consumption data must be cross-checked against operating hours and production volumes to identify anomalies.

### 9.6 Treatment of Missing or Incomplete Data

192. Where monitoring data are missing or incomplete, projects must assess the materiality of the data gap. Minor gaps may be addressed through conservative estimation methods supported by historical data or proxy measurements, provided assumptions are documented and justified.
193. If data gaps materially affect the accuracy of net carbon removal calculations and cannot be conservatively resolved, affected biochar quantities must be excluded from crediting for the monitoring period.
194. Reconstruction of data must never result in higher credited removals than would have occurred with complete and accurate data.

### 9.7 QA/QC for Emissions and Leakage Calculations

195. Emission factors used in project and leakage emission calculations must be sourced from approved references or conservative defaults. Application of emission factors must be consistent across monitoring periods.
196. Activity data used in emissions calculations must be traceable to primary records such as fuel purchase invoices, meter readings, or transport logs. Cross-checks must confirm that emissions are not omitted or double-counted.
197. Where leakage is identified, QA/QC procedures must ensure that assumptions regarding causality and attribution are conservative and evidence-based.

### 9.8 QA/QC for Permanence and Reversal Risk

198. Projects must implement QA/QC procedures to ensure that biochar storage or application remains consistent with approved permanence pathways. This includes verification of custody arrangements, storage conditions, and land management practices.
199. Any event or change that could affect permanence must be documented and assessed promptly. Failure to detect or report potential reversals constitutes a QA/QC non-conformance.

### 9.9 Documentation and Recordkeeping QA/QC

200. All QA/QC activities must be documented in a manner that allows independent verification. Documentation must clearly link monitoring data, QA/QC checks, and corrective actions to specific monitoring periods and credited quantities.
201. Records must be retained for the duration required under PCS rules, including any post-crediting permanence obligations.

### 9.10 Corrective Actions and Continuous Improvement

202. Where QA/QC issues are identified, projects must implement corrective actions to address root causes and prevent recurrence. Corrective actions may include changes to monitoring procedures, additional training, equipment upgrades, or revised data management practices.
203. Projects are encouraged to review QA/QC performance periodically and incorporate improvements as part of continuous improvement, provided changes remain consistent with PCS requirements.

### 9.11 QA/QC Review Prior to Reporting

204. Before submission of monitoring reports and Tool outputs, projects must conduct a final QA/QC review to confirm that all requirements of this chapter have been met. Any unresolved issues must be disclosed transparently in the monitoring report.

## Chapter 10 - Reporting Requirements

### 10.1 Purpose of Reporting

205. Reporting under PCS-MT-002 ensures that all information required to assess eligibility, quantify net carbon removal, and evaluate permanence is presented in a transparent, consistent, and verifiable manner. Reporting requirements are designed to allow validation and verification bodies to independently reconstruct calculations and assess compliance with this methodology.
206. Reports must clearly distinguish between monitored data, calculated results, assumptions, and conservative adjustments applied under uncertainty.

### 10.2 Monitoring Report Structure

207. Each monitoring report must follow a standardized structure to ensure consistency across projects and monitoring periods. At a minimum, the report must include:

* Project identification and monitoring period definition
* Description of feedstock sourcing and any changes during the period
* Summary of biochar production activities and operating conditions
* Quantification of gross and net carbon removal
* Summary of project emissions and leakage
* Permanence and reversal risk status
* QA/QC summary and corrective actions
* Statement of consistency with PCS-MT-002 requirements

208. The structure must allow clear cross-referencing between narrative sections, tables, Tool outputs, and evidence references.

### 10.3 Reporting of Biomass Feedstock Information

209. The report must disclose all biomass feedstocks used during the monitoring period, including classification as residual or dedicated biomass. For each feedstock category, the report must include quantities used, source locations, and confirmation of sustainability and eligibility.
210. For dedicated biomass, the report must include an explicit statement confirming continued compliance with sustainability and land-use requirements, including any material changes since the previous monitoring period.

### 10.4 Reporting of Biochar Production and Characterization

211. Projects must report total biochar produced during the monitoring period, clearly distinguishing eligible biochar from excluded fractions. Reported quantities must reconcile with monitored biomass inputs and yield calculations.
212. Carbon content and stability indicators used to determine the stable biochar fraction must be reported, including testing methods, sampling frequency, and results. Where default values or conservative assumptions are applied, these must be explicitly stated and justified.

### 10.5 Reporting of Carbon Removal Quantification

213. The report must present gross biochar carbon, stable carbon fraction applied, and resulting gross carbon removal in CO₂ equivalent. All calculations must align with Chapter 6 and be traceable to Tool outputs.
214. Net carbon removal must be clearly reported after deduction of project emissions and leakage. Any monitoring-period exclusions or conservative adjustments must be disclosed transparently.

### 10.6 Reporting of Project Emissions and Leakage

215. All project-related fossil greenhouse gas emissions included in quantification must be reported by source category. The report must identify activity data, emission factors applied, and resulting emissions.
216. Where leakage emissions are included, the report must describe the source of leakage, the rationale for inclusion, and the calculation approach used. If leakage is assessed as immaterial and excluded, the basis for that determination must be documented.

### 10.7 Reporting on Permanence and Reversal Risk

217. The report must include a statement confirming that biochar storage or application remains consistent with approved permanence pathways. Any events, changes, or observations relevant to permanence during the monitoring period must be disclosed.
218. If a reversal occurred or is suspected, the report must quantify affected carbon and describe corrective actions taken in accordance with Chapter 7.

### 10.8 Reporting of QA/QC Activities

219. A summary of QA/QC procedures conducted during the monitoring period must be included. This summary must identify any non-conformities, data gaps, or deviations from approved procedures and describe how they were resolved.
220. Where conservative assumptions were applied due to QA/QC findings, these must be clearly disclosed and reflected in reported results.

### 10.9 Evidence Referencing and Traceability

221. All reported data and calculations must be supported by evidence referenced using the standardized evidence reference structure. The report must allow verifiers to locate supporting documents without ambiguity.
222. Evidence references must be consistent with entries in the Tool and must cover the entire monitoring period.

### 10.10 Versioning and Tool Declaration

223. 2The report must specify the version of PCS-MT-002 applied and the version of any associated calculation tool used. The project must confirm that the Tool has not been altered and that all calculations were performed using the approved version.
224. Any deviations from standard Tool operation must be disclosed and justified.

### 10.11 Reporting Timelines

225. Monitoring reports must be submitted in accordance with PCS reporting timelines. Late submission or incomplete reporting may delay verification or credit issuance.

## Chapter 11 - Verification Requirements

### 11.1 Purpose of Verification

226. Verification under PCS-MT-002 provides independent assurance that reported carbon removal quantities are accurate, conservative, and fully compliant with this methodology and the PCS framework. Verification confirms that credited removals represent real, durable atmospheric carbon removal and that all monitoring, quantification, and permanence requirements have been met.
227. Verification applies to both initial project validation and periodic verification of monitoring reports throughout the crediting period.

### 11.2 Scope of Verification

228. The scope of verification includes, at a minimum:

* Confirmation of project eligibility under PCS-MT-002
* Review of feedstock sourcing and classification
* Assessment of biochar production processes and characterization
* Verification of quantification calculations and Tool integrity
* Evaluation of project emissions and leakage accounting
* Assessment of permanence provisions and reversal risk management
* Review of monitoring systems, QA/QC procedures, and reporting
* Confirmation of evidence completeness and traceability

229. Verification must cover the entire monitoring period for which credit issuance is requested.

### 11.3 Verification of Eligibility and Applicability

230. The verifier must confirm that the project remains eligible under PCS-MT-002, including compliance with feedstock eligibility rules for residual and dedicated biomass.
231. This includes reviewing documentation related to biomass sourcing, sustainability safeguards, land-use conditions (for dedicated biomass), and confirmation that biochar production and storage pathways remain consistent with approved eligibility criteria.
232. Any material deviation from eligibility conditions must be identified and assessed prior to credit issuance.

### 11.4 Verification of Biochar Production and Characterization

233. The verifier must assess whether biochar production is conducted through eligible thermochemical processes and whether biochar output is intentional, measurable, and traceable.
234. Verification must include review of:

* Production records and operating logs
* Biomass input and biochar output reconciliation
* Biochar yield calculations
* Laboratory analyses for carbon content and stability indicators

235. The verifier must confirm that characterization results are representative of the monitoring period and that stability classifications have been conservatively applied. Where default values or conservative assumptions are used, the verifier must assess their appropriateness.

### 11.5 Verification of Quantification and Calculations

236. The verifier must independently review the quantification of gross and net carbon removal. This includes checking that:

* Stable biochar carbon is calculated in accordance with Chapter 6
* Stability fractions are correctly applied
* Conversion to CO₂ equivalent is accurate
* Project emissions and leakage are fully included and correctly calculated

237. The verifier must confirm that baseline removals are correctly set to zero and that no avoided emission claims are implicitly or explicitly included.
238. Sampling or recalculation may be performed to verify consistency and accuracy.

*Note: Validation and verification bodies shall apply**PCS-CN-001 — Biochar Stability Metrics and Application in Quantification***\_ when assessing stability indicators, laboratory evidence, and application of stability fractions.\_

### 11.6 Verification of Tool Integrity

239. Where a PCS-approved calculation tool is used, the verifier must confirm that:

* The correct tool version has been applied
* Protected cells and formulas remain unaltered
* Inputs are consistent with monitoring data
* Internal consistency checks pass without unresolved errors

240. Any manual adjustments, overrides, or deviations from standard Tool operation must be disclosed, justified, and assessed for compliance.

### 11.7 Verification of Project Emissions and Leakage

241. The verifier must assess whether all material fossil greenhouse gas emissions attributable to the project have been included. This includes emissions from biomass handling, transport, production processes, and dedicated biomass cultivation where applicable.
242. Where leakage is included, the verifier must review the causal link between project activities and leakage sources and confirm that calculations are conservative and evidence-based.
243. Where leakage is excluded on the basis of immateriality, the verifier must assess the justification and ensure that exclusion does not result in over-crediting.

### 11.8 Verification of Monitoring Systems and QA/QC

245. The verifier must evaluate the adequacy and implementation of monitoring systems and QA/QC procedures described in Chapters 8 and 9.
246. This includes review of:

* Measurement equipment calibration
* Data collection and aggregation processes
* Handling of missing or incomplete data
* Corrective actions taken in response to QA/QC findings

247. The verifier must confirm that QA/QC procedures have been effectively implemented and that any non-conformities have been resolved or conservatively addressed.

***Note:***\_ Validation and verification bodies shall apply\_***PCS-CN-004 — Evidence Sufficiency, Conservative Defaults, and Data Gaps***\_ when assessing evidence adequacy, default application, and treatment of missing or uncertain data.\_

### 11.9 Verification of Permanence and Reversal Risk

248. The verifier must assess whether credited biochar remains stored or applied in accordance with approved permanence pathways. This includes reviewing records related to storage locations, land management practices, custody arrangements, and monitoring observations.
249. Any events or conditions that could affect permanence must be evaluated. Where a reversal has occurred or is suspected, the verifier must confirm that affected quantities have been properly quantified and deducted in accordance with Chapter 7.

*Note: Validation and verification bodies shall apply**PCS-CN-002 — Stability vs Permanence: Boundary, Obligations, and Reversals***\_ when assessing stability claims, permanence obligations, and the treatment of reversals.\_

### 11.10 Evidence Review and Traceability

250. The verifier must confirm that all data and calculations are supported by appropriate evidence. Evidence must be complete, traceable, and consistent with reported values.
251. The verifier must be able to reconstruct key calculations using provided evidence and must identify any gaps or inconsistencies that could materially affect reported results.

### 11.11 Verification Findings and Conclusions

252. Verification findings must clearly state whether the project and monitoring report are compliant with PCS-MT-002 and whether reported net carbon removal quantities are eligible for credit issuance.
253. Any non-conformities must be classified and documented, with clear requirements for corrective actions where applicable.
254. The verification statement must reference the applied methodology version, tool version, monitoring period, and verified quantities.

### 11.12 Treatment of Non-Conformities

255. Non-conformities identified during verification must be addressed prior to credit issuance unless PCS governance rules allow conditional issuance. Corrective actions must be documented and verified as appropriate.
256. Material non-conformities that cannot be resolved must result in exclusion of affected quantities or suspension of credit issuance.

### 11.13 Verification Frequency and Re-Verification

257. Verification must be conducted at intervals defined by PCS governance rules. Re-verification may be required where material changes occur or where PCS requires additional assurance.
258. Projects must cooperate fully with verifiers and provide access to facilities, records, and personnel as reasonably required.
