Acid sulfate Management Plan Reference Document OPW19-0239 · OPW19/0239

PROCEDURE B
Treatment and Verification of Excavated ASS


B4 (e) Verification Testing
Verification samples shall be collected for treated material at a rate of 1 sample per 250 m3. The samples
shall be formed by compositing materials from three randomly selected locations. Samples shall be
collected over the full thickness of the treated lot. The Chromium Suite shall be conducted on each sample
to confirm net acidity by Acid Base Accounting.

B5.       PERFORMANCE CRITERIA
To confirm adequate lime treatment, laboratory testing must demonstrate the following:

     A neutralising capacity of more than 1.5 times the sum of existing plus potential acidity, all measured in
      the same units (and using a minimum safety factor of 1.5) and

     A pHKCL value of equal or greater than 6.5

B6.       CONTINGENCY MEASURES
Additional lime treatment and further verification testing shall be conducted where adequate neutralisation is
not initially indicated.

B7.      PERFORMANCE INDICATORS
           Item                                            Performance Indicator

                                  An appropriate earthworks strategy has been prepared to                   track
 Earthworks strategy
                                   characterisation, treatment and verification of each earthworks lot.

 Liming rates                     Correct liming rates have been applied

                                  Verification samples collected for each identifiable 250 m3 of treated material
 Treatment verification            If verification shows material has a positive net acidity, additional treatment
                            
                                   has been employed

 Non conformance                  All non-conformances have been reported and rectified


B8.      MONITORING AND REPORTING
Records shall be kept to verify volumes of soils transported to the treatment facility or treated in-situ.

The Site Supervisor shall be responsible for ensuring that samples are collected at a rate of 1 per 250 m3, if
the above liming rates are not used, to formulate more specific liming rates.

The Site Supervisor shall be responsible for ensuring that lime neutralisation and verification tests are
completed for each 250 m3 of excavated ASS material.
The Site Supervisor shall maintain a register of testing results and a record of inspections.

A summary report of all test results and inspections shall be complied by the Site Supervisor each week and
retained on site.




April 2019
J000799-003-R-Rev0 – Procedure B                         3/3