Maryland Code, Housing and Community Development § 4-1307

(a) The Department shall establish for participating counties a sliding scale formula, based on income, under which residential well owners with lower incomes are eligible for larger grants and those with higher incomes are eligible for smaller grants.

(b) The combined county and State grants shall equal at least 10% but not more than 25% of the cost of the water treatment system that the residential well owner installs.