Workers rights and immigrant advocacy groups are among several calling on Hyundai to guarantee new job standards and equity measures in the aftermath of the company’s use of child labor in auto manufacturing in Alabama.

The groups, in an Aug. 27 letter to Hyundai Motor America CEO José Muñoz, are urging the Korean automaker’s American operations to enter a community benefits agreement with the groups.

A CBA is a private contract between community groups and an employer which calls for certain measures from a developer or company toward members of the community. Its provisions could be enforced through binding arbitration.

In the letter, the groups say they are “deeply concerned” about several issues, including “Hyundai’s recent track record with child labor in its supply chain in the U.S.”

Among the groups included are the Alabama Appleseed Center for Law and Justice, Alabama Arise, Alabama State Conference of the NAACP, Alabama Forward, Coosa Riverkeeper, Faith in Action Alabama, Greater Birmingham Ministries, Central Alabama Labor Council, Greater-Birmingham Alliance to Stop Pollution, Alabama Coalition for Immigrant Justice, Alabama Interfaith Power and Light and others.

Reuters originally reported last July that children were employed at SMART Alabama, which has supplied parts for Hyundai’s Montgomery plant since 2003.

Two suppliers, SL Alabama and SMART, have terminated their relationships with third-party staffing agencies which, the company said, falsely certified that they had screened and cleared children as being eligible to work.

Both SL Alabama and JK USA, an Opelika temporary employment agency, earlier this year paid fines from federal court and the Alabama Department of Labor, after investigators found workers as young as 13 employed in one factory.

In February, Hyundai announced plans to divest its majority stake from an auto supplier in Alabama following its investigation, as well as other measures to report the use of underage labor.

Hyundai earlier this year announced it would build an electric vehicle plant in Georgia. This month, Hyundai announced it is investing $290 million to upgrade production at its Montgomery plant, to support ongoing production of the Tucson SUV and the Santa Cruz.