Starting with the End in Mind - Howard County's Journey through Master Planning and Dryer Start-up to Create a Marketable Product

Background Howard County owns and operates the Little Patuxent Water Reclamation Plant (LPWRP), located in Savage, Maryland. The LPWRP is permitted to treat an annual average daily flow of 29.2 million gallons per day (mgd), with a current average daily flow of 20 mgd. Howard County historically generated a Class A Exceptional Quality (EQ) alkaline-stabilized biosolids product (through the RDP process), that was beneficially used in the bulk agriculture market. The RDP process and biosolids management was contracted to a third-party contractor (TPC). While the program was successful, it had challenges including generation of large quantities of biosolids to manage, elevated pH in soils routinely receiving the biosolids, a newly adopted winter ban on land application of organic materials (including biosolids), and specific limitations on existing agricultural outlets due to the implementation of Maryland's phosphorus (P) index. Objective Recognizing these challenges, the County engaged the HDR & Material Matters Team (Team) to complete a biosolids master plan (2013) and subsequent preliminary engineering report (PER) (2014). At the start of the project, the County developed the following project goal: 'Develop a Biosolids Master Plan that provides a framework for reliable, cost-effective, and socially responsible treatment and beneficial use of LPWRP biosolids in a changing and unpredictable regulatory environment.' To aide in selecting a technology best suited to meet the County's needs, Material Matters conducted a market analysis and regulatory review for Class A/EQ biosolids in Mid-Atlantic region. The objective was to identify the product or product(s) best suited to meet the project goal. Methodology Material Matters was responsible for conducting an initial market analysis in the local community, establishing product quality characteristics and specifications, and outside-the-gate costs as part of the initial Master Planning effort. Material Matters provided customer-preferred characteristics for each of the biosolids products based on the viable market requirements. A regulatory review was conducted to define/assess the current and future regulatory requirements for both Class B and EQ biosolids to confirm and clarify the meaning of new and proposed regulatory language. Bulk sale to soil blenders was identified as a primary outlet, driven by regulatory challenges related to phosphorus (P) content of the biosolids - bulk sales to soil blenders would not be impacted by new P rules. With the support of the market assessment findings, Howard County personnel concluded that anaerobic digestion with thermal drying was the technology combination best suited to meet the set goal. Multiple thermal drying technologies were evaluated as part of the PER and a second, detailed market assessment was completed to identify which dried biosolids product type was best suited for the local soil blending market (Figure 1). The County selected the Haarslev belt drying technology for the ultimate processing of its material to create a dried Class A/EQ product for the most promising non-agriculture market identified: soil blending (Figure 1). Findings and Current Status[ Material Matters was able to provide support for the project within budget based on taking advantage of our local experience with regional regulators and other utilities. The Material Matters team is currently revisiting these efforts to develop a details distribution plan to provide the County with a recipe to successfully distribute the product during the first years following dryer start-up. The distribution plan includes tools for Howard County to advertise the product (Figure 2), example distribution plan based on market findings (Figure 3), and an overall roadmap for continual program evaluation and improvement (Figure 4). As of the time of this publication, viable options include direct distribution to a local soil blender and large farm for a small net revenue. By 'Starting with the End in Mind' and continual pursuit of local market options, the Material Matters team has helped the County save up to $300,000 per year in outside-the-gate costs (Figure 5).