A root cause analysis is conducted and a corrective action plan is prepared for non-conformities identified during wastewater and sludge testing

Conduct a RCA/CAP for test result non-conformities, as per ‘alerts’ in the ClearStream Report.

ClearStream Report

Once the wastewater and sludge sampling and testing are completed and results are published by the supplier in their ZDHC Gateway account, they can generate and download a “ClearStream Report”. 

Wastewater

Parameters that “do not meet” limit values detailed in the requirements are highlighted in the ClearStream Report as a orange cell “alerts”.

Sludge

Parameters that are not within the required limits are indicated by a “red cross”.

Root cause analysis (RCA)

A supplier should conduct a root cause analysis (RCA) for these wastewater and sludge non-conformities, either for the input chemical inventory or effluent treatment operations, in order to locate the cause.

For non-conformaties of sludge disposal pathways D, E, F and G, immediate solutions should be included in the CAP and the supplier should evaluate if other sludge disposal options are available to dispose accordingly.

Corrective Action Plan (CAP)

The supplier must complete the RCA/CAP details (using the RCA/CAP template) for any non-conformities identified in the ClearStream Report for a specific wastewater testing cycle and upload the completed document, including the RCA/CAP template, to their ZDHC Gateway account to ensure visibility for connected brands.

Furthermore, the supplier is expected to complete the CAP within the indicated timeline and keep records to confirm the completion in the next reporting cycle.

Long term CAP measures should be implemented to improve the quality of the sludge so that it is authorised and suitable for the original disposal route via source reduction, treatment modifications and other actions such as moving to disposal pathway A, B and C. Wherever possible, sludge disposal pathways A, B and C should be preferred.

Download wastewater and sludge RCA/CAP template

Root cause analysis for non-conformities

In case of non-conformities to the ZDHC Wastewater and Sludge Guidelines, as shown in a ClearStream Report, a supplier should conduct a Root Cause Analysis (RCA) to generate and implement a Corrective Action Plan (CAP). Given below are some recommendations of steps to be followed for RCA of conventional parameters and ZDHC MRSL Parameters listed in the ZDHC Wastewater and Sludge Guidelines:

Wastewater root cause analysis (RCA): Conventional parameters

Step 1

Identify the conventional parameters of concern through the ClearStream Report.

Step 2

Complete the following:

• Review the Chemical Inventory List (CIL) and study which chemicals from the inventory can impact the parameters of concern (for example, chemicals with high COD or BOD or low fixation reactive dyes for excessive colour).
• Review the production recipe and the consumption of such chemical products to measure their impact on the organic load on the ETP.
• Work with the ETP manager to understand whether ETP chemicals have been used correctly, in line with load calculations.
• Conduct a full assessment of the ETP operations and confirm proper maintenance.
• Check if any treatment system was shut down for an extended time prior to the collection of the wastewater sample.
• Investigate if any other activities occurred before the sampling, which may have caused a shock load or excess flow to the ETP, such as emptying and washing chemical containers. 
• Investigate whether any other engineering and operational aspects of the wastewater treatment plant may have created non-compliant test results, such as faulty aerators or non-replenishment of biomass/activated sludge.

Step 3

Document your RCA and plan corrective actions in line with the root cause identified.

Step 4

Implement the Corrective Action, prepare a CAP document and upload on the ZDHC Gateway.

Step 5

Prepare an SOP to prevent the same failure from happening again. Train your team as required.

Wastewater Root Cause Analysis (RCA): MRSL Parameter

Step 1

Identify MRSL substances of concern from the ClearStream Report.

Step 2

• Review your Chemical Inventory List (CIL) to identify chemical products where ZDHC MRSL substances may have been used intentionally. (For example, non-conformity for APEOs could be due to purchase and use of an APEO based soaping agent or non-conformity for a phthalate could be due to the use of a plastisol ink in printing, see ZDHC Guidance Sheets on the ZDHC MRSL.)
• Review also other indirectly used chemical products in the manufacturing facility such as cleaning, maintenance, utility, lab and sundry chemical products. (for example, presence of chromium in the wastewater could be due to the use of Potassium Dichromate used in the lab for shade development).
• Reach out to your chemical formulator for any additional information or conduct third- party testing required to determine any MRSL contaminations in the chemical products.
• Determine if MRSL risks are possible from raw materials or input raw water used in the manufacturing facility.
• Conduct a full assessment of the ETP operations and confirm proper maintenance.

Step 3

Document your RCA and plan corrective actions in line with the root cause identified.

Step 4

In case you need to substitute a chemical product, search on the ZDHC Gateway Chemical Module for a suitable alternative.

Step 5

Implement the Corrective Action, prepare a CAP document and upload on the ZDHC Gateway (refer to CAP template).

Step 6

Ensure that the purchasing of ZDHC MRSL conformant chemical products is always done as per the purchasing policy.