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Proposed Compost Facility FAQs

Proposed County Compost Facility Frequently Asked Questions

Below are questions we’ve been hearing from the public and property owners in the vicinity of the proposed facility. This page will be updated with new questions and answers, so please check back. Feel free to ask a question that is not on this page by using the question/comment form.

In 2019, a contractor for Boulder County conducted an analysis of sites for the potential development of zero waste infrastructure, which included construction and demolition debris and composting management facilities. The study reviewed three potential locations and the old Rainbow Nursery was recommended by the study team as the most suitable site for the facility for several reasons including location, development costs, proximity to potential facility users, distance from neighboring dwellings, and because it offered the largest potential reduction in greenhouse gas emissions. Read the study’s summary findings report.

Boulder County purchased the Conservation Easement on the Rainbow Tree Nursery in 1994 using open space funds. Then in 2018, the county purchased the remainder of the property and its water rights, again using open space funds for future zero waste infrastructure. When the same landowner owns both a property and a conservation easement restricting the property, the property interests merge together and the conservation easement ceases to exist. There has not been a conservation easement on the property since the county’s 2018 purchase.

When the county purchased the land and water in 2018, the county stated in the public record and closing documents that the county was considering using the property to further the county’s zero waste goals. The county commissioners acknowledged at that time that they agreed to buy the property that there would be a public process required in the future to convert the property to a non-open space use.

If the site is approved for use as a composting facility, the Parks and Open Space Department will go through the required disposition of open space procedures. The open space sales tax ballot language requires publishing notices in the paper, a presentation to Parks and Open Space Advisory (POSAC) Committee, then a Board of County Commissioners (BOCC) public hearing, and a wait of 60 days after BOCC approval. If the BOCC agrees to dispose of the property, the county will reimburse the open space sales tax funds for the entire amount of land and conservation easement value. Those funds (about $740,000) will be used to purchase new open space. The county will keep the water rights for agricultural use.

There has not been a conservation easement on the property since the county’s 2018 purchase. Boulder County purchased the Conservation Easement on the Rainbow Tree Nursery in 1994 using open space funds. Then in 2018, the county purchased the remainder of the property and its water rights, again using open space funds for future zero waste infrastructure. Per common law, when a landowner owns both a property and a conservation easement restricting the property, the property interests merge together and the conservation easement ceases to exist.

Salazar v. Terry, 911 P.2d 1086, 1090-1091 (Colo. 1996) provides this explanation:

Easements, such as a “right of way,” burden one estate to the benefit of the other estate. The burdened estate is servient to the dominant estate which benefits from the easement. When the dominant and servient estates come under common ownership, the need for the easement is destroyed. Specifically, “if the owner of an easement in gross comes into ownership of an estate in the servient tenement, the easement terminates to the extent that the ownership of that estate permits the uses authorized by the easement.”

In the current situation with the Rainbow Nursery site, the county had owned a conservation easement interest in the Rainbow Nursery property, which was the dominant estate. In 2018, the county acquired the fee simple interest in the property, which was the servient estate. Once the county owned all of the rights in the property, the conservation easement was extinguished because a single owner cannot hold both the fee simple estate and the encumbrance and the two interests are held to have merged together into one, unencumbered, estate.

If the proposed facility is not built on the site and the property is sold to another entity, it is possible that the conservation easement will be re-established on the property.

Yes, in situations that have included conservation easements intended to be temporary to protect property during interim steps in regulatory processes, land acquisition deals where permanent restrictions occurred later, and situations where the county, local municipality, and landowner all agreed. For example, some conservation easements have language in them allowing for conservation easements to be terminated if the land lies near municipalities and the county and city later agree that the property is appropriate for development. This has occurred within the context of the county’s transferable development rights (TDRs) program, where properties become sending sites that are protected by a conservation easement and their development rights are moved to sites near the municipalities that become receiving sites for the TDRs and that are then developed.

In other situations, such as this, the county has acquired a conservation easement interest in a property and then later invested more money to acquire the land for open space.

In addition, conservation easement interests have been taken from the county by condemning authorities. When any other type of disposition occurs and open space sales and use tax dollars were used to acquire the county’s interest, the money is reinvested in additional open space interests.

When an easement is proposed to be removed from a property, the county follows standard public notice protocols before making decisions at public hearings or business meetings.

This property is currently zoned “A” – Agricultural. Article 4 Section 102 of the Boulder County Land Use Code allows for a composting facility and a forestry processing and sort yard as permitted uses of the property.

Boulder County Public Works is reviewing comments from the public and referral agencies and departments regarding the proposed compost facility. The project team has informed Boulder County Community Planning and Permitting that it is not ready to proceed to a Planning Commission public hearing for consideration of the Special Use Review application. The project team will continue to analyze the construction and operation of the proposed facility and will refine plans, if warranted, to ensure that, if built, the location, buildings, and operations are environmentally sound and will operate with the original intent of the scope of the project. The project may be placed on the agenda for Planning Commission and Board of County Commissioners public hearings in the future if and when the Boulder County Public Works Department determines that it is ready to proceed. Information will be posted here and sent to the project email listserv if and when there are any new developments, including public hearings.

Comments on the project (designs, location, concept, etc.) can be submitted at any time. All comments will be provided to the project team, the Planning Commission, and the Board of County Commissioners for their review.

If built, the proposed facility will be a Class III Composting Facility that will accept vegetative waste (leaves, grass, branches, limbs, and forest materials) and animal waste, manure, food scraps, and food processing vegetative waste. Biosolids are being discussed and may be accepted in the future, but they will not be accepted if/when the facility opens.

Biosolids are a product of the wastewater treatment plant process. During treatment, liquids are separated from solids. The solids are then treated physically, biologically, and chemically to produce a semisolid, nutrient-rich product known as “biosolids.” The digestion process within a wastewater treatment plant is facilitated by microorganisms, mainly bacteria. The cell structure of the bacteria comprise a large portion of biosolids. Varying quality standards (classes) associated with biosolids ensure that they are processed, handled, and beneficially used in a manner that minimizes risk to human health. Class designations are based on treatment requirements for pollutants, pathogens, and vector (e.g., flies) attraction reduction as well as general requirements and management practices defined by the United States Environmental Protection Agency (EPA). Class designations include Class A and Class B. Class A biosolids can be distrbuted/used on/in virtually all sectors of lawn and garden. Class B are restricted to permitted agricultural use.

Composting produces a Class A biosolid compost product that includes processes to eliminate pathogens, including viruses. Biosolids compost is not biosolids; biosolids are a part of the feedstock used to create compost. Biosolids are blended with high-carbon bulking agents such as ground brush and limbs and then composted. The composting process further digests and decomposes the feedstock, via natural activity of bacteria, fungi, and molds, to create compost.

Biosolid composting and composting facilities are regulated and permitted. The compost produced meets EPA requirements for use and distribution to all sectors of the compost market with the exception of certified organic crops.

All material delivered to the proposed facility would be accepted in enclosed trucks that will be unloaded in an enclosed facility. Materials would be mixed in the facility and then moved to one of 16 covered and completely enclosed concrete bunkers (see example photo below). The environment inside the covered bunker would be closely controlled and monitored to control the rate of aeration. The material would go through an eight-week compost cycle. After the cycle is completed, the material will have little to no odor potential.

Proposed countywide compost facility
The cover used for the bunker has unique physical properties that would help control odor and air permeability (see graph below). The material will be able to withstand rain, snow, and wind, but still allow carbon dioxide and water vapor that can also be controlled by the facility. The cover allows air (oxygen and carbon dioxide) and water vapor to escape, while extensively retaining odor compounds. During the composting process, a fine film of water condensation develops on the inside of the covers, which captures odors and other gases like volatile organic compounds (VOCs). These materials are dissolved in the film of water and drop back into the composting material where they can be consumed by microorganisms. Read a report from the San Joaquin Valley Air Pollution Control District on the covers the facility will use.

Odor control for compost using Gore coverBy accepting the material from covered trucks in and enclosed facility and then storing it under specially designed covers in concrete bunkers, we’ll also be able to control pests and prevent material from being carried by the wind.

If constructed, the composting bunkers will be fully contained to fully protect groundwater. Even with the barriers in place, the county will monitor all groundwater by using an array of wells that will reach into area groundwater. All facility infrastructure would be kept at least 50-feet away from the ditch system that borders the property. A majority, if not all, of wastewater collected would be collected in above ground tanks and reused in the composting process. If there’s any water remaining, it would be brought to a nearby wastewater treatment facility for proper disposal.

The facility will accept waste from commercial and residential sources. Finished compost material generated on-site will be available for residential and agricultural users.

One of the primary goals of the project is to ensure the safety of everyone traveling US 287 and of people visiting the proposed facility. A detailed traffic study was completed to determine the impact the proposed facility woulld have on travel along US 287 and it showed that the existing roadway system can adequately accommodate projected traffic volumes. By slightly adjusting the timing of the traffic signals on US 287 at CO 52 and at Lookout Road, large gaps would be provided in the traffic flow to accommodate for large trucks exiting the facility. The entrance to the facility will be from US 287, so surrounding smaller roads should not see an increase in day-to-day traffic. In addition, many of these trucks are already traveling through the area using US 287 and CO 52 to reach the nearest operational compost processing facility in Keenesburg, CO.

One of the goals of the project is to protect the numerous trees that have been allowed to grow since the nursery closed a few years ago. Currently, 40% of the trees on the property are Ash, which are susceptible to the Emerald Ash Borer insect that has been identified and has already decimated many trees throughout the county. Ash trees will be removed to help prevent additional spread of the insect no matter if the compost facility is constructed or not. A majority of the the remaining trees will remain in place or will be relocated on site in order to accommodate the facility. The lot would be developed within the remaining shelterbelt in order to screen the operations and preserve the aesthetics of the nursery. The county is also planning on planting numerous new trees that would also aid in creating a visual screen from neighboring properties and passing motorists.

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