- A light blanket of snow covers the preserve. Open water and birds in The Cove Estuary.
Crossroads Addresses Soil Contamination.
In the fall of 2023, Crossroads at Big Creek’s commitment to caring for land will take a new direction. For years, restoration work has been above ground – planting trees and removing invasive species, and even, in the mid-1990s, allowing Big Creek to remeander and reclaim its natural course after being channeled
for agriculture. We will soon, however, be addressing an issue that’s just below the surface: lead arsenate contamination that is the result of decades of orchard spraying.
Like much of Door County, the property now known as Crossroads was once cultivated for cherry and apple orchards. Orchards first appeared in Door County in the 1880s when dairy farmers began to diversify, planting small portions of their land in orchard. As fruit production became more lucrative,
that acreage increased. The 1950s were a high point in fruit production with 10,500 acres planted with cherry trees and 2,200 acres planted with apples.
Black and white aerial photographs taken between 1938 and 1974 identify 1,750 separate orchards in Door County. The orchards are apparent, showing up in the photos as tiny dots in neat rows. Of these 1,750 orchards, 66-percent were cherries, 24-percent apple and 10-percent mixed. Pesticides played a large role in the rise of orchards. Fewer insects led to increased yields and increased yields led to increased profits. By the late 1940s, Door County had 1.1 million trees and produced 10 percent of the nation’s cherries.
The pesticide most widely used was lead arsenate. Cherry trees were sprayed two or three times a season, and apples, because of their longer growing season, were sprayed six to eight times. The Door County UW-Extension Department issued instructions to orchardists on when and how the chemicals were to be applied. The lead arsenate was received in powdered form. Two-to-three pounds of powder was mixed with 100 gallons of water. It took about 200 to 300 gallons of solution to cover one acre of orchard.
While high concentrations of lead and arsenic are typically found in the soil throughout an orchard, the highest concentrations are found in the “hot spots” – areas where chemicals were mixed, loaded or stored – due, in part, to incidental spills.
In an article titled, “The Apple Bites Back,” environmental science writer Ernie Hood explains, “Even though arsenic residue was recognized as a problem as early as 1919, [lead arsenate] was the most widely used pesticide in the nation—recommended by the USDA and applied to millions of acres of crops—until the late 1940s, when DDT (considered at the time to be safer and more effective) became available. [Lead arsenate] continued to be used in some locations into the 1970s and was ultimately banned in 1988.”
Lead and arsenic occur naturally in the soil. The State Department of Agriculture, Trade and Consumer Protection (DATCP) considers 8 parts per million (ppm) arsenic and 52 ppm lead to be general background levels in Wisconsin. The State of Wisconsin requires mitigation in areas with levels that
exceeds 100 ppm arsenic or 400 ppm lead.
While arsenic is a known human carcinogen and exposure to lead can cause neurological damage, the main concern is direct contact. Lead and arsenic bind to the soil and do not generally travel by water; wells tested at Crossroads over many years have shown no elevated levels.
Remediation is a costly and involved process. Crossroads has contracted with Sand County Environmental, of Amherst, Wisconsin, for soil testing and supervision. The first steps involve research into historic land use and soil testing. Once a contaminated area is mapped, the top six inches of soil, where the contamination exists, is removed and hauled away to a state regulated site where it will be recorded, tracked and used to cap landfills.
Crossroads contains two mixing sites, one that was fed by pipe with water from Big Creek, and one that was fed by water from a well that has since been capped and abandoned. All told, approximately 30,000 square feet (two-thirds of an acre) of land will be impacted by the removal. Approximately 200 cubic yards of soil (300 tons or 13 dump trucks full) will be removed.
The price tag for the soil remediation project is just over $60,000. Seventy-five percent of the cost will be covered by DATCP’s Agricultural Chemical Cleanup Program and $10,000 may be covered by a cost-share program of the Door County Soil and Water Conservation Department. Crossroads expects its costs to be approximately $6,000.
Following the excavation, clean topsoil will be spread to cap the site. Restoration will include the planting of grasses, trees and shrubs. Crossroads expects the excavation and topsoil spreading to take less than a week. Once excavation work is done, restoration of the site will begin. During the process, visitors will
be asked to avoid certain parts of the preserve.
Being a model
“Our mission is to restore and care for the land and to share what we learn,” said executive director Laurel Hauser. “We see this soil remediation as a responsibility and also an opportunity. Because Crossroads is known and used by so many people, we want the community to be aware of what we’re doing and why
and to understand the background. Hopefully, it helps us as a community make better choices in the future. There’s a Maya Angelou quote that applies well to this situation: ‘Do the best you can until you know better. Then, when you know better, do better.’”
Crossroads will be scheduling a forum in which Ken Ebbott, senior project manager and geologist at Sand County Environmental, will discuss the project and answer questions. Watch Crossroads’ website for more information.
Williamson, Patty. September 2009.
“A Sea of Orchards.” Door County Living.
Hood, Ernie. August 2006. “The Apple Bites Back: Claiming Old Orchards
for Residential Development. Environmental Health Perspectives.