MERRILLVILLE, Ind. (AP) — Northern Indiana Public Service Co. is paying a $900,000 fine after state regulators found that the utility failed to keep accurate maps and records of its underground natural gas lines.

The settlement approved Wednesday by the Indiana Utility Regulatory Commission instructs the company to improve its pipeline safety management system.

The agency had issued violation notices to NIPSCO last year alleging 230 violations involving the timeliness of location services and 31 errors in locating underground lines stemming from inaccurate or inaccessible company pipeline maps and records.

The utility commission says NIPSCO “lacked a sense of urgency” to maintain updated pipeline records. The Merrillville-based utility provides natural gas to 810,000 customers across the northern one-third of Indiana.

NIPSCO says it’s committed to improving its operations.