RFI - Stormwater Management Plan

              STORMWATER MANAGEMENT AND MAINTENANCE PLAN
ELEMENT:                         MAINTENANCE OF RAPID INFILTRATION PITS (RIP’s)

1.     Objective                 To ensure ongoing function of RIP’s in reintroducing
                                 runoff into the subsoil and prevent surcharge/flooding.
       Consequences of Failure   Damage to POSCW areas
2.     Management Strategy       RIP internal surface to remain free of silt/sediment build-
                                 ups.

                                 RIP grates to remain clear and free of debris or blockages.
3.     Actions                   Maintenance Contractor to be issued with laminated
                                 copies of final ALTA Projects drawings A6769/22/PD01
                                 to PD05 for reference.

                                 Swales and RIP surface grates to be kept clear of any
                                 debris or blockages.

                                 Maintenance contractor with appropriate enclosed spaces
                                 qualifications and procedures in place to enter each RIP
                                 to inspect at quarterly intervals and after any event where
                                 more than 50mm of rain has fallen.

                                 Any debris, leaf litter etc accumulated in the RIP to be
                                 removed and disposed of lawfully.

                                 Upper BIDIM A14 filter layer to be inspected and if more
                                 than 50% covered in silt or mud replaced.

                                 Upper BIDIM A14 filter layer to be replaced annually.

                                 When replacing upper filter, the sand layer below to be
                                 inspected for discolouration and contamination and if
                                 present ALTA Projects to be notified for review and further
                                 advice.

                                 RIP walls and balance pipes to be inspected for any signs
                                 of cracking or degradation. If observed ALTA Projects to
                                 be notified.

                                 All removed filter layers, sand, sediment, silt to be
                                 disposed of lawfully.
4.     Performance Indicators    No surcharging of RIPs.
                                 No overflow from rock pitched weirs.
                                 No mponding of water in RIPs.
5.     Frequency/Deadline        Inspections after rain events or quarterly (whichever
                                 comes first)
7.     Reporting and Review      Maintenance Contractor to make entries in service diary.
                                 Site Owner to review service diary annually.

ELEMENT :                MAINTENANCE OF OVERLAND FLOW PATH and PIPEWORK

1.     Maintenance Objective     To ensure ongoing function of Overland Flow Path
       Consequences of Failure   And underground pipes
                                 Possible flooding of building during storm events.
2.     Management Strategy       Landscaped overland flow path to be maintained in good
                                 condition, clear and unblocked.
                                 Underground pipework to be maintained in good
                                 condition, clear and unblocked.

3.     Actions                   Maintenance Contractor to be issued with laminated
                                 copies of final ALTA Projects drawings.