CITY OF LARCHMONT

Larchmont WWTP is owned and operated by Consolidated Utilies, a privately held company located in Savannah, Georgia.

RATIONALE FOR AMTS UPGRADE:

Larchmont determined that a system upgrade was necessary because (1) the population served and the related daily flow rates were increasing substantially from approximately 0.3 mgd to 0.6 mgd. In addition, a more demanding and stringent discharge permit was implemented by the Georgia Department of Environmental Quality (GDEQ).

New requirements for treatment were becoming more stringent such that Biochemical Oxygen Demand (“BOD”) was to be discharged at levels not to exceed of 10 mg/l, Total Suspended Solids (“TSS”) were to be discharged at levels not to exceed of 20 mg/l, Ammonia (NH3) was to be discharged at levels not to exceed of 5 mg/ and Fecal Coliform was to be discharged at levels not to exceed of 200 mg/l.

Without changed practices, compliance by Larchmont with more stringent standards from GDEQ, at more than twice the daily flow rate, was regarded as improbable.

Larchmont was impressed with the performance history of ADS and the predicted capability of AMTS to provide solid year round performance and to substantially reduce the high cost associated with periodic sludge disposal. Briefly, AMTS provides the quality treatment of mechanical plants in lagoons at significant savings in capital and operating costs. The AMTS process combines ADS’s proprietary diffusion aeration products, engineered surface area (“AquaMats® ”) and bioaugmentation (“Bacta-Pur®”) technologies to form a very stable, and low-maintenance integrated system for natural microbial treatment of municipal wastewater. Because of the efficiency of AMTS, sludge handling is typically not necessary for up to 10 years or longer.

Larchmont considered a number of different proposals and selected the AMTS from ADS because it offered the most impressive performance at low capital and O & M costs, all supported by a 5-year performance guarantee.

DESCRIPTION OF AMTS UPGRADE:

The basic goal of the AMTS for Larchmont was to convert and upgrade the existing facilities to a high performance lagoon system so that discharge requirements were consistently achieved with a comfortable margin.

Above ground header pipe and high efficiency diffusion aeration tubing were laid across the width of all primary and second lagoons. Baffles were installed in each primary and secondary lagoons. The primary lagoons were also equipped with Bacta-Pur® BactivatorsTM to continuously supply a metered and activated quantity of XLG, a Bacta-Pur® sludge digesting product.

AMTS COSTS---CAPITAL, OPERATING AND MAINTENANCE:

Capital costs incurred by Larchmont for the AMTS upgrade were approximately $200,000 in equipment and installation related services.

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