AltEn Community Update

The below information has been provided in an effort to help keep the community informed on a more frequent basis about progress at the AltEn site. 

Ever since AltEn ceased operations at its facility in Mead in 2021, the AltEn Facility Response Group (FRG) has been voluntarily working under the guidance of the Nebraska Department of Environment and Energy (NDEE) to stabilize the AltEn site and develop a Remedial Action Plan (RAP) for the site. The FRG’s top priorities have been and continue to be to help ensure the safety of the surrounding community and environment. To-date, there has been no evidence of impacts to local drinking water.

The FRG is working diligently with the NDEE to identify the most effective and safest methods to address the current environmental conditions on the AltEn site. The remedial action plans (RAP) will recommend remediation for components remaining on-site, including wastewater, sludge, and wet cake.

APRIL 16, 2024

Wet Cake Pilot Project

The FRG will soon restart the pilot project. The plan is to mobilize heavy equipment in May, followed by solidification, transportation and disposal. Once trucks are rolling again, wet cake removal is expected to last up to six weeks. 

Pilot Project restarts this Spring Evaluate in-pile mixing vs. use of pug mill Truck loads will be wrapped in plastic and tarped Truck wheels will be washed and visually inspected before leaving the site Exposed wet cake will be covered at the end of each day Air quality monitoring will be performed Stormwater will be contained and treated Expected 2024 schedule Coordinating with contractors regarding finalplans and schedule Mobilize in May Solidification, transportation and landfilldisposal to commence in May/June andcontinue for approximately five to six weeks

Lagoon Water Treatment and Land Application

Water continues to be treated at an on-site treatment facility. As of April 12, 79.7 million gallons have been treated; an estimated 35 million gallons remain, excluding stormwater. Land application will continue through Spring and is anticipated to be complete by the end of the year. 

Water treatment Treated a total of 79.7 million gallons through April 12, 2024 Analytical results continue to show good water quality     suitable for land application NDEE approved the water treatment system permitmodification, adding two carbon units Additional carbon units expected to be online this month Estimated 35 million gallons remain to be treated, excludingstormwater Expect to complete treatment in 2024 Land application of treated water Spring 2024 application 11 million gallons have been applied to land Approximately 920 farmland acres have been identified for Fall 2024 sofar, which should provide sufficient land for applying 25 million gallons Spring and Fall land applications will continue in 2025 until all treatedwater is applied

More Site Progress

Water continues to be pumped from the Northwest Lagoon for treatment. Various air, water and soil samples continue to be evaluated; reports and notifications are shared with the Nebraska Department of Environment and Energy (NDEE) as needed. 

Monitoring well installation Five new monitoring wells (MWs) installed week of March 4 Quarterly sampling Collected samples from 11 existing and five new MWs in week of March 11 NDEE collected split samples of five new MWs Results Groundwater flow direction continues to be away from Mead toward the south-southeast None of the pesticides exceeded their screening level except for one compound at AltEn-MW5 Nitrogen compounds present in background groundwater and is representative of regional groundwater quality
Pesticide (Drinking Water Level, source) Clothianidin (580 ug/L USEPA HHBP) Metalaxyl/Mefenoxam (300 ug/L, NDEQ Table A-1) Thiamethoxam (71 ug/L, USEPA HHBP) Fluoxastrobin (89 ug/L, USEPA HHBP) ------------------------------------------------------------------- Chlorantraniliprole (9,350 ug/L, USEPA HHBP) Sedaxane (650 ug/L, USEPA HHBP) All units in micrograms per liter (µg/L) ND – Not Detected in the sample
Groundwater Monitoring Results – Nitrogen Compounds
Other Activities Submitted the 2023 Annual Land Application Report to NDEE on April 1 Provided NDEE with a pilot project notification on April 11 to post on its portal Wet Cake Subsoil Characterization Report to be submitted to NDEE this month Continue to pump water from the Northwest Lagoon to the Southeast Lagoon for treatment following whale lancing Continue lagoon solids technical evaluation including solidification bench-scale testing, other dewatering methods Received analytical results for the Northwest Lagoon subsoil samples last week and will share them with NDEE and the community following our review and evaluation

Stay Informed

Check alteninfo.com for the latest updates about AltEn site activities.