Irrigation water quality for sodium, chloride, bicarbonate and boron ions

Dear all, I am referring to irrigation water qualities wherein the primary source of water is treated sewage from sewage treatment plants.  The national regulations of this particular country (cannot disclose) uses the term 'me/l' for Sodium and Chloride. I was wondering what it could be? I thought it is milli equivalent/litre, but the prescribed values for Na & Cl do not match any way near to expected concentration from general STPs. Any idea what could this term mean, 'me/l'?  They have clubbed it with Sodium Adsorption Ratio, which is a dimensionless number. Best Regards Anvar Mansuri