RFI - Attachment F - Engineering Report

         HUNTER ENVIRONMENTAL SERVICES
                                 Stormwater and Catchment Management
                  Geoffrey J. Hunter (MIEANZ); Churchill Fellow 1996 — Soil & Water Management
                       Jillian M. Hunter; Post Graduate Diploma Adult & Community Education
                                   52 Centre Crescent Blaxland NSW Australia 2774
                           Phone (mobile): 0437 502 952 E-mail: [email protected]

                                          A.B.N. : 90 264 168 968

Our Ref.: 1410                                                                           15 September 2014
Technical Director
Stormwater 360 Australia
PO Box 792
BOTANY NSW 1455

Attention: Mr Michael Wicks

                     RE: Peer Review of Product Evaluation Report
           Stormwater Management StormFilter® Stormwater Treatment System
                      Mitchell Community College Mooresville, NC

Thank you for commissioning Hunter Environmental Services to peer review the field study of
the StormFilter® technology undertaken by Contech Engineered Solutions within the parking
lot of the Mitchell Community College in Mooresville North Carolina USA.

The primary goal of the field study and subsequent report “was to collect performance data in
order to support the approval of the StormFilter system and its potential inclusion into the
North Carolina Stormwater BMP Manual. A major condition of the approval for continued
participation in the PEP [Preliminary Evaluation Period] program was the execution of an
additional field evaluation in accordance with the conditions outlined in the PEP program.”

Consequently monitoring and evaluation of the performance of the StormFilter® system,
installed in the Mitchell Community College carpark, was carried out to demonstrate its
effectiveness at removing Total Suspended Solids (TSS) and nutrients (Phosphorus and
Nitrogen) from runoff, as required by the PEP program.

Our review has concentrated on answering the key issues raised in your commissioning letter
of 5 August 2014, namely:

        “Review of treatment system, sampling setup and equipment and sampling methodology.
        Confirmation of independent sampling chain of custody external to Contech Engineered
         Solutions.
        Review of Report including calculations, discussions and conclusions. (refer to Discussion
         and Conclusion sections within this Peer Review).
        Comment on the comparisons of EMC’s from the study compared with local data ie
         Duncan & Fletcher + others (if applicable) to help provide transferability of results.
        Comment on the comparison of nutrient species or the composition of soluble species
         compared with local data.



HES – StormFilter® System Peer Review                                                                 Page 1