Case Study: Sea Pines Resort, Hilton Head, SC
Organics Pretreatment as Part of an Integrated System for Managing Materials
The Sea Pines Resort is part of an island community where the power and majesty of nature is ever-present. So, too, are the realities of living on an island. The local landfill has an estimated operating lifespan of 5-11 years, reminding businesses and residents that there is no “away” and motivating them to find more innovative ways of managing the materials they consume and rely on for daily life. Sea Pines Resort is comprised of six restaurants, a 60 room hotel, 12,000 sf of meeting spaces, retail shops and a pier. The resort also manages a community of 425 homes and villas and three golf courses.
The company was motivated to find a better solution for managing their material streams because they had a hunch that they were paying a lot of money to collect and transport valuable materials to the landfill. That’s a lot of containers to rent or buy and the fees for collection and hauling only kept growing. They were convinced that they could come up with a more sustainable system and save money too. The company first focused on maximizing the value of their recyclable solid waste. In particular, they wanted to get cardboard out of the bins that also contained organics because they acted like a sponge, increasing their weight and increasing odors in collection areas. The resort now recycles an average of 50% of the cardboard, aluminum, plastics, metals and glass they use in back of house. The savings have been significant: trash hauling costs between $130-$170 per ton compared to recycling costs of $95 per ton.
Next, they turned their attention to food waste and oyster shells. In 2017, the resort processed over 65 tons of food waste which included 6.4 tons of coffee grounds and over 8 tons of oyster shells. To tackle the oyster shell waste, kitchen staff decided to collect the shells in buckets which are then delivered to a site run by the Department of Natural Resources where they are bagged and placed offshore to seed new oyster beds in an effort to protect the shoreline, create fish habitat and improve water quality (oysters clean 2.5 gallons of water per hour).
Then, to reduce the amount of food waste being sent to the landfill, the resort started recycling pre-consumer or “back-of-house” (organics generated in kitchen or food prep areas) because they found that post-consumer or “front-of-house” food waste created too many issues with contamination for the amount of nutrients recovered. The one exception is that they do process
food waste from all of the catered events the facility hosts where they can control contamination. Food waste is managed following a value hierarchy designed by the resort that is consistent with Charles Fraser, the founder’s vision for an environmentally sustainable business.
Food waste is processed according to what the resort believes has the highest environmental and economic value for their operations:
Vermiculture composting (15-20% of food waste)
Tony Wartko, Director of Facility Services and Sustainability explains, “we give the worms what they like to eat best, which is the pre-consumer vegetative and bakery wastes. Our golf courses currently spend $3,000 per year for worm tea for cultivating our putting greens, so our eventual goal is to save
these costs by producing our own supply of this amazing fertilizer. Right now, we use the worm castings and tea to fertilize small vegetable, herb and flower gardens.”
The resort uses a [make and model] rotary drum in-vessel composter to process the bulk of the food waste generated. The composter is especially good at processing some of the recalcitrant vegetative wastes such pineapple rinds, corn husks, peaches and avocados (and pits!).
Pretreatment / Dehydrator (20-35%)
The resort operates three GAIA dehydrators (models G-100H, GC-150 and a G-30H). Certain units are dedicated to certain restaurant locations and are used primarily to process meat scraps and renderings, soups and citrus rinds. The output from the GAIA units are fed into the in-vessel composter for curing into a more mature, stable compost that is then used for gardens and landscaping beds throughout the resort. Wartko sa
id that the resort has been very pleased with the performance of the GAIA units.
When asked what types of materials pose problems as contaminants, he cited metal utensils, large bones or an occasional stray oyster shell can lodge in the unit and bind the spiral auger. They have not had a unit break as a result but the unit needs to be stopped to clear whatever is obstructing the auger. Wartko offered another word of advice , “Don’t mix corn husks with sugar and oil or you will find yourself making molasses which is not good for the long-term health of your equipment!”
The Sea Pines Resort is a great example of how businesses can include multiple solutions for processing food waste that include a healthy return on investment in the form of cost savings from reductions of trash hauling fees, the number of trash bins used for storage, as well as savings from producing its own compost for restaurant gardens and eventually fertilizer for golf course maintenance.