{"data":{"schemaVersion":"realm.mine-profile.v1","generatedAt":"2026-10-13T11:26:59.401Z","identity":{"mine_id":"3901496","name":"Read Screen","status":"Abandoned","status_date":"2006-09-29","mine_type":"Surface","coal_metal":"M","commodity":"Construction Sand and Gravel","state":"SD","county":"Minnehaha","nearest_town":"Sioux Falls","operator_id":"L15666","operator_name":"Concrete Materials Company","controller_id":"0176802","controller_name":"Knife River Corporation","district":"M4","office":"Duluth District","employees":0,"latitude":null,"longitude":null},"coverage":{"contributingSources":7,"registeredSources":20,"sourceRows":19},"relationships":{"schemaVersion":"realm.temporal-relationships.v1","temporalSemantics":{"validTime":{"granularity":"date","bounds":"inclusive","nullStart":"start date not published in the upstream history row","nullEnd":"open-ended in the upstream history row; not independent proof of present control"},"transactionTime":{"observedAt":"2026-10-13T11:19:05.459773+00:00","meaning":"time the checksum-addressed MDRS artifacts were observed by the PostgreSQL ingestion"},"derivation":{"controllerControlsOperator":"intersection of controller and operator valid-time intervals evidenced through this mine","currentIdentity":"current controller and operator are asserted only by the MDRS Mines snapshot"}},"current":{"mine":{"type":"mine","id":"3901496","name":"Read Screen"},"operator":{"type":"operator","id":"L15666","name":"Concrete Materials Company"},"controller":{"type":"controller","id":"0176802","name":"Knife River Corporation"},"source":{"datasetId":"msha-mines","observedAt":"2026-10-13T11:19:05.459773+00:00"}},"edges":[{"type":"controller_controls_mine","subject":{"type":"controller","id":"M11946","name":"Gerald P  Sweetman"},"object":{"type":"mine","id":"3901496","name":"Read Screen"},"validFrom":"1950-01-01","validTo":"2018-10-03","current":false,"derived":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|M11946|1950-01-01|2018-10-03"}},{"type":"operator_operates_mine","subject":{"type":"operator","id":"L15666","name":"Concrete Materials Company"},"object":{"type":"mine","id":"3901496","name":"Read Screen"},"validFrom":"2006-07-14","validTo":null,"current":true,"derived":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|L15666|2006-07-14|"}},{"type":"controller_controls_operator","subject":{"type":"controller","id":"M11946","name":"Gerald P  Sweetman"},"object":{"type":"operator","id":"L15666","name":"Concrete Materials Company"},"validFrom":"2006-07-14","validTo":"2018-10-03","current":false,"derived":true,"evidenceMineId":"3901496","intervalAnomaly":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|L15666|2006-07-14|M11946|1950-01-01|152752"}},{"type":"controller_controls_mine","subject":{"type":"controller","id":"M09717","name":"MDU Resources Group Inc"},"object":{"type":"mine","id":"3901496","name":"Read Screen"},"validFrom":"2018-10-04","validTo":"2023-05-31","current":false,"derived":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|M09717|2018-10-04|2023-05-31"}},{"type":"controller_controls_operator","subject":{"type":"controller","id":"M09717","name":"MDU Resources Group Inc"},"object":{"type":"operator","id":"L15666","name":"Concrete Materials Company"},"validFrom":"2018-10-04","validTo":"2023-05-31","current":false,"derived":true,"evidenceMineId":"3901496","intervalAnomaly":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|L15666|2006-07-14|M09717|2018-10-04|147394"}},{"type":"controller_controls_mine","subject":{"type":"controller","id":"0176802","name":"Knife River Corporation"},"object":{"type":"mine","id":"3901496","name":"Read Screen"},"validFrom":"2023-06-01","validTo":null,"current":true,"derived":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|0176802|2023-06-01|"}},{"type":"controller_controls_operator","subject":{"type":"controller","id":"0176802","name":"Knife River Corporation"},"object":{"type":"operator","id":"L15666","name":"Concrete Materials Company"},"validFrom":"2023-06-01","validTo":null,"current":true,"derived":true,"evidenceMineId":"3901496","intervalAnomaly":false,"source":{"datasetId":"msha-controller-operator-history","observedAt":"2026-10-13T11:19:05.459773+00:00","recordKey":"3901496|L15666|2006-07-14|0176802|2023-06-01|37866"}}],"coverage":{"historyRecords":3,"edgeCount":7,"intervalAnomalies":0,"sourceDatasetId":"msha-controller-operator-history"}},"sources":[{"id":"msha-accidents","name":"Accident, Injuries, and Illnesses","domains":["safety","contractors"],"products":["incident trends","severity rates","equipment patterns","peer denominators"],"rowCount":1,"firstDate":"2004-09-23","lastDate":"2004-09-23","metrics":{"daysLost":0,"injuries":1,"fatalities":0,"recentRows":0,"restrictedDays":0,"contractorRecords":0},"periods":{},"recentRecords":[{"SOURCE_ROW_NUMBER":"11542","DOCUMENT_NO":"220042810075","ACCIDENT_DT":"09/23/2004","DEGREE_INJURY":"NO DYS AWY FRM WRK,NO RSTR ACT","CLASSIFICATION":"OTHER","ACCIDENT_TYPE":"Struck by flying object","OCCUPATION":"Maintenance man, Mechanic,  Repair/Serviceman, Boilermaker, Fueler, Tire tech, Field service tech","NO_INJURIES":"1","DAYS_LOST":"0","NARRATIVE":"TWO EMPLOYEES WERE REPLACING A WINDOW IN A LOADER. THE WINDS WERE VERY STRONG, BLOWING AROUND A LOT OF DUST, DIRT AND SAND. ONE EMPLOYEE FELT SOMETHING BLOW IN HIS LEFT EYE. LATER IT SEEMED OK; COULD NOT SEE ANYTHING IN IT. FRIDAY MORNING IT SEEMED OK; LATER HE SAW A PARTICLE ON THE SURFACE. TRIED TO WASH IT OUT WITHOUT SUCCESS. HE WENT TO THE CLINIC.","sourceDate":"2004-09-23"}]},{"id":"msha-addresses","name":"Addresses of Record","domains":["identity","logistics"],"products":["entity resolution","address history","facility geocoding"],"rowCount":1,"firstDate":"2006-09-29","lastDate":"2006-09-29","metrics":{},"periods":{},"recentRecords":[]},{"id":"msha-controller-operator-history","name":"Controller and Operator History","domains":["identity","compliance"],"products":["historical ownership attribution","operator transitions","valid-time joins"],"rowCount":3,"firstDate":"2006-07-14","lastDate":"2006-07-14","metrics":{"recentRows":0,"currentOperatorTenures":3,"completedOperatorTenures":0},"periods":{},"recentRecords":[]},{"id":"msha-inspections","name":"Inspections","domains":["safety","compliance"],"products":["inspection mix","on-site hours","event context","citation rate denominator"],"rowCount":2,"firstDate":"2004-09-15","lastDate":"2006-09-14","metrics":{"inspectors":2,"recentRows":0,"onSiteHours":5.75,"inspectionHours":17.75,"inspectionSamples":0},"periods":{},"recentRecords":[{"SOURCE_ROW_NUMBER":"1136949","EVENT_NO":"1093189","INSPECTION_BEGIN_DT":"09/14/2006","INSPECTION_END_DT":"09/14/2006","ACTIVITY_CODE":"E01","ACTIVITY":"Regular Safety and Health Inspection","NBR_INSPECTOR":"1","SUM_TOTAL_INSP_HOURS":"10.75","SUM_TOTAL_ON_SITE_HOURS":"2.75","sourceDate":"2006-09-14"},{"SOURCE_ROW_NUMBER":"350526","EVENT_NO":"1080477","INSPECTION_BEGIN_DT":"09/15/2004","INSPECTION_END_DT":"09/15/2004","ACTIVITY_CODE":"01","ACTIVITY":"REGULAR INSPECTION","NBR_INSPECTOR":"1","SUM_TOTAL_INSP_HOURS":"7","SUM_TOTAL_ON_SITE_HOURS":"3","sourceDate":"2004-09-15"}]},{"id":"msha-mine-production-quarterly","name":"Mine Employment and Production — Quarterly","domains":["production","safety","compliance"],"products":["production trend","employee hours","rate denominators","seasonality"],"rowCount":9,"firstDate":null,"lastDate":null,"metrics":{},"periods":{"2006-Q2":{"hours":160,"employees":1,"production":0},"2006-Q1":{"hours":0,"employees":0,"production":0},"2005-Q4":{"hours":0,"employees":0,"production":0},"2005-Q3":{"hours":0,"employees":0,"production":0},"2005-Q2":{"hours":0,"employees":0,"production":0},"2005-Q1":{"hours":0,"employees":0,"production":0},"2004-Q4":{"hours":936,"employees":2,"production":0},"2004-Q3":{"hours":310,"employees":2,"production":0}},"recentRecords":[]},{"id":"msha-mine-production-yearly","name":"Mine Employment and Production — Yearly","domains":["production","safety","compliance"],"products":["annual trend","backfill","quarterly reconciliation"],"rowCount":2,"firstDate":null,"lastDate":null,"metrics":{},"periods":{"2004":{"hours":1246,"employees":2,"production":0},"2006":{"hours":160,"employees":1,"production":0}},"recentRecords":[]},{"id":"msha-mines","name":"Mines","domains":["identity","production","logistics"],"products":["mine identity","status","commodity","location","operator and controller"],"rowCount":1,"firstDate":null,"lastDate":null,"metrics":{},"periods":{},"recentRecords":[]}],"safety":{"href":"/api/v1/mines/3901496/safety","description":"Full-period safety series, top CFR sections and paginated activity. Requires PostgreSQL."},"silica":{"href":"/api/v1/mines/3901496/silica","description":"Dedicated silica records, measurements, sample status and trends. Defaults to the snapshot year; use year=all for history."},"externalContext":{"eia":null,"title30":{"snapshot":{"chapterCount":6,"featuredSectionCount":100,"latestAmendedOn":"2026-08-14","latestIssueDate":"2026-08-14","partCount":206,"sectionCount":5954,"upToDateAsOf":"2026-08-19"},"regulations":[],"fullCorpus":"/data/title30-sections.json"}}},"meta":{"representation":"json","mineId":"3901496","dataSource":"postgres","snapshotId":"2026-10-13T11:19:05.459773+00:00","completedAt":"2026-10-13T11:26:59.401Z","sourceCount":20,"totalRows":17906804}}